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Shao S, Liao H, Zhou S, Li Y, Yu H, Dai X, Zhu Q, Hua Y, Wang C, Zhou K. Isolated non-immune mediated second-degree atrioventricular block in fetus: natural history and predictive factors for spontaneous recovery. Ultrasound Obstet Gynecol 2024. [PMID: 38642334 DOI: 10.1002/uog.27662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 03/29/2024] [Accepted: 04/03/2024] [Indexed: 04/22/2024]
Abstract
OBJECTIVES To uncover the clinical course of fetal isolated non-immune mediated second-degree AVB and determine the factors associated with the spontaneous recovery for fetal non-immune second-degree atrioventricular block (AVB). METHODS A total of 20 fetuses with isolated, non-immune mediated second-degree AVB were prospectively recruited between 2014 and 2022. These fetuses were divided into the spontaneous recovery group (n=12) and the non-spontaneous recovery group (n=8). Maternal and fetal basic characteristics, intrauterine and postnatal outcomes were compared between groups. RESULTS Twelve fetuses restored 1:1 atrioventricular conduction in utero and did not recur during the postnatal follow-up period. The residual eight fetuses maintained as second-degree AVB and six of them were aborted due to parental request in utero. Of the two live children with second-degree AVB, one of them progressed to complete AVB at the latest follow up at the age of 34 months, but without any symptoms, heart enlargement or dysfunction. The residual one progressed to complete AVB and was finally diagnosed with type 2 long-QT syndrome. Fetuses in the spontaneous recovery group presented with earlier gestational age at diagnosis (20.0[17.0-26.0] vs. 24.5[18.0-35.0] weeks, p=0.004) and higher atrial rate (147[130-160] vs 138.00[125.00-149.00] bpm, p=0.006) in comparison with the non-spontaneous recovery group. A cut-off value of 22.5 weeks of gestational age and 144 bpm of atrial rate at diagnosis could predict the failure of spontaneous recovery, with sensitivities of 87.5%, 75%, and specificities of 92.0%, 87.5%, respectively. CONCLUSIONS The outcome of fetal non-immune second-degree AVB was favorable. Earlier gestational age at diagnosis and higher atrial rate were related to spontaneous reversion for isolated non-immune-mediated second-degree AVB. However, prenatal gene test should be performed for those with persistent AVB to exclude the heritable disorders including LQTS. These findings may provide important references for clinical management and prenatal counseling. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- S Shao
- Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | - H Liao
- Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | - S Zhou
- Department of Obstetrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Y Li
- Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | - H Yu
- Department of Obstetrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
| | - X Dai
- Department of Ultrasound, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Q Zhu
- Department of Ultrasound, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Y Hua
- Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | - C Wang
- Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | - K Zhou
- Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
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Thomson KL, Jiang C, Richardson E, Westphal DS, Burkard T, Wolf CM, Vatta M, Harrison SM, Ingles J, Bezzina CR, Kroncke BM, Vandenberg JI, Ng CA. Clinical interpretation of KCNH2 variants using a robust PS3/BS3 functional patch-clamp assay. HGG Adv 2024; 5:100270. [PMID: 38219013 PMCID: PMC10840334 DOI: 10.1016/j.xhgg.2024.100270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 01/07/2024] [Accepted: 01/08/2024] [Indexed: 01/15/2024] Open
Abstract
Long QT syndrome (LQTS), caused by the dysfunction of cardiac ion channels, increases the risk of sudden death in otherwise healthy young people. For many variants in LQTS genes, there is insufficient evidence to make a definitive genetic diagnosis. We have established a robust functional patch-clamp assay to facilitate classification of missense variants in KCNH2, one of the key LQTS genes. A curated set of 30 benign and 30 pathogenic missense variants were used to establish the range of normal and abnormal function. The extent to which variants reduced protein function was quantified using Z scores, the number of standard deviations from the mean of the normalized current density of the set of benign variant controls. A Z score of -2 defined the threshold for abnormal loss of function, which corresponds to 55% wild-type function. More extreme Z scores were observed for variants with a greater loss-of-function effect. We propose that the Z score for each variant can be used to inform the application and weighting of abnormal and normal functional evidence criteria (PS3 and BS3) within the American College of Medical Genetics and Genomics variant classification framework. The validity of this approach was demonstrated using a series of 18 KCNH2 missense variants detected in a childhood onset LQTS cohort, where the level of function assessed using our assay correlated to the Schwartz score (a scoring system used to quantify the probability of a clinical diagnosis of LQTS) and the length of the corrected QT (QTc) interval.
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Affiliation(s)
- Kate L Thomson
- Oxford Genetics Laboratories, Churchill Hospital, Oxford, UK
| | - Connie Jiang
- Faculty of Medicine and Health, UNSW Sydney, Kensington, NSW, Australia; Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia
| | - Ebony Richardson
- Centre for Population Genomics, Garvan Institute of Medical Research and UNSW Sydney, Sydney, NSW, Australia; Centre for Population Genomics, Murdoch Children's Research Institute, Melbourne, VIC, Australia
| | - Dominik S Westphal
- Institute of Human Genetics, Klinikum rechts der Isar, School of Medicine and Health, Technical University of Munich, Munich, Germany; Department of Internal Medicine I, Klinikum Rechts der Isar, School of Medicine and Health, Technical University of Munich, Munich, Germany; European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart
| | - Tobias Burkard
- Department of Congenital Heart Disease and Pediatric Cardiology, German Heart Center Munich, Technical University of Munich, School of Medicine and Health, Munich, Germany
| | - Cordula M Wolf
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart; Department of Congenital Heart Disease and Pediatric Cardiology, German Heart Center Munich, Technical University of Munich, School of Medicine and Health, Munich, Germany; DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany
| | | | | | - Jodie Ingles
- Centre for Population Genomics, Garvan Institute of Medical Research and UNSW Sydney, Sydney, NSW, Australia; Centre for Population Genomics, Murdoch Children's Research Institute, Melbourne, VIC, Australia
| | - Connie R Bezzina
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart; Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, University of Amsterdam, Amsterdam UMC, Amsterdam, the Netherlands
| | - Brett M Kroncke
- Vanderbilt Center for Arrhythmia Research and Therapeutics, Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jamie I Vandenberg
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia; School of Clinical Medicine, UNSW Sydney, Darlinghurst, NSW, Australia.
| | - Chai-Ann Ng
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia; School of Clinical Medicine, UNSW Sydney, Darlinghurst, NSW, Australia.
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3
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Wolfes J, Uphoff J, Kemena S, Wegner F, Rath B, Eckardt L, Frommeyer G, Ellermann C. Divergent electrophysiologic action of dapagliflozin and empagliflozin on ventricular and atrial tachyarrhythmias in isolated rabbit hearts. Front Cardiovasc Med 2024; 11:1369250. [PMID: 38455723 PMCID: PMC10918010 DOI: 10.3389/fcvm.2024.1369250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 02/12/2024] [Indexed: 03/09/2024] Open
Abstract
Background The use of SGLT-2 inhibitors has revolutionized heart failure therapy. Evidence suggests a reduced incidence of ventricular and atrial arrhythmias in patients with dapagliflozin or empagliflozin treatment. It is unclear to what extent the reduced arrhythmia burden is due to direct effects of the SGLT2 inhibitors or is solely a marker of improved cardiac function. Methods One hundred five rabbit hearts were allocated to eight groups and retrogradely perfused, employing a Langendorff setup. Action potential duration at 90% of repolarization (APD90), QT intervals, effective refractory periods, conduction velocity, and dispersion of repolarization were obtained with monophasic action potential catheters. A model for tachyarrhythmias was established with the IKr blocker erythromycin for QT prolongation associated proarrhythmia as well as the potassium channel opener pinacidil for a short-QT model. An atrial fibrillation (AF) model was created with isoproterenol and acetylcholine. With increasing concentrations of both SGLT2 inhibitors, reductions in QT intervals and APD90 were observed, accompanied by a slight increase in ventricular arrhythmia episodes. During drug-induced proarrhythmia, empagliflozin succeeded in decreasing QT intervals, APD90, and VT burden whereas dapagliflozin demonstrated no significant effects. In the presence of pinacidil induced arrhythmogenicity, neither SGLT2 inhibitor had a significant impact on cardiac electrophysiology. In the AF setting, perfusion with dapagliflozin showed significant suppression of AF in the course of restitution of electrophysiological parameters whereas empagliflozin showed no significant effect on atrial fibrillation incidence. Conclusion In this model, empagliflozin and dapagliflozin demonstrated opposite antiarrhythmic properties. Empagliflozin reduced ventricular tachyarrhythmias whereas dapagliflozin showed effective suppression of atrial arrhythmias.
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Affiliation(s)
- Julian Wolfes
- Department of Cardiology II, Electrophysiology, University Hospital Münster, Münster, Germany
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Gholipour M, Samidoost P, Moayerifar M, Ghasemzadeh G. A case report of QTc prolongation: Drug induced or myocarditis in Severe Acute Respiratory Syndrome Coronavirus 2. SAGE Open Med Case Rep 2024; 12:2050313X241233432. [PMID: 38384983 PMCID: PMC10880539 DOI: 10.1177/2050313x241233432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Accepted: 01/31/2024] [Indexed: 02/23/2024] Open
Abstract
Remdesivir is a nucleotide prodrug of an adenosine analog. It binds to the viral Ribonucleic Acid (RNA)-dependent RNA polymerase and inhibits viral replication by terminating RNA transcription prematurely. Remdesivir has demonstrated in vitro and in vivo activity against Severe Acute Respiratory Syndrome Coronavirus 2; it also acts in vitro neutralization activity against the Omicron variant and its subvariants. We reported a 54-years-old woman admitted with Coronavirus disease 2019. Considering to require a high fraction of inspired oxygen therapy (⩾0.6) and based on lung high resolution computed tomography, Remdesivir therapy was ordered for 5 days. She experienced palpitations and dizziness 2 days after starting Remdesivir therapy. Her QTc interval was prolonged on the electrocardiogram without any significant electrolyte abnormalities or concomitant use of medications. Although the cardiac side effects of Remdesivir therapy have been well documented, in a few cases reported the association between Remdesivir therapy and QTc interval prolongation. Since, QTc interval prolongation has the potential risk of sudden cardiac death, the clinicians should be aware of mentioned association and check electrocardiogram daily, as well as other laboratory exams.
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Affiliation(s)
- Mahboobeh Gholipour
- Department of Cardiology, Healthy Heart Research Center, Heshmat Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Pirooz Samidoost
- Department of Razi Clinical Research Development Unit, Guilan University of Medical Sciences, Rasht, Iran
| | - Mani Moayerifar
- Department of Razi Clinical Research Development Unit, Guilan University of Medical Sciences, Rasht, Iran
| | - Golshan Ghasemzadeh
- Healthy Heart Research Center, Heshmat Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
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Bjelic M, Goldenberg I, Younis A, Chen AY, Huang DT, Yoruk A, Aktas MK, Rosero S, Cutter K, McNitt S, Sotoodehnia N, Kudenchuk PJ, Rea TD, Arking DE, Zareba W, Ackerman MJ, Goldenberg I. Risk Prediction in Male Adolescents With Congenital Long QT Syndrome: Implications for Sex-Specific Risk Stratification in Potassium Channel-Mediated Long QT Syndrome. J Am Heart Assoc 2024; 13:e028902. [PMID: 38240206 DOI: 10.1161/jaha.122.028902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 07/06/2023] [Indexed: 02/07/2024]
Abstract
BACKGROUND Sex-specific risk management may improve outcomes in congenital long QT syndrome (LQTS). We recently developed a prediction score for cardiac events (CEs) and life-threatening events (LTEs) in postadolescent women with LQTS. In the present study, we aimed to develop personalized risk estimates for the burden of CEs and LTEs in male adolescents with potassium channel-mediated LQTS. METHODS AND RESULTS The prognostic model was derived from the LQTS Registry headquartered in Rochester, NY, comprising 611 LQT1 or LQT2 male adolescents from age 10 through 20 years, using the following variables: genotype/mutation location, QTc-specific thresholds, history of syncope, and β-blocker therapy. Anderson-Gill modeling was performed for the end point of CE burden (total number of syncope, aborted cardiac arrest, and appropriate defibrillator shocks). The applicability of the CE prediction model was tested for the end point of the first LTE (excluding syncope and adding sudden cardiac death) using Cox modeling. A total of 270 CEs occurred during follow-up. The genotype-phenotype risk prediction model identified low-, intermediate-, and high-risk groups, comprising 74%, 14%, and 12% of the study population, respectively. Compared with the low-risk group, high-risk male subjects experienced a pronounced 5.2-fold increased risk of recurrent CEs (P<0.001), whereas intermediate-risk patients had a 2.1-fold (P=0.004) increased risk . At age 20 years, the low-, intermediate-, and high-risk adolescent male patients had on average 0.3, 0.6, and 1.4 CEs per person, respectively. Corresponding 10-year adjusted probabilities for a first LTE were 2%, 6%, and 8%. CONCLUSIONS Personalized genotype-phenotype risk estimates can be used to guide sex-specific management in male adolescents with potassium channel-mediated LQTS.
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Affiliation(s)
- Milica Bjelic
- Clinical Cardiovascular Research Center, Division of Cardiology University of Rochester Medical Center Rochester NY USA
- Department of Anesthesiology St. Elizabeth's Medical Center Boston University School of Medicine Boston MA USA
| | - Ido Goldenberg
- Clinical Cardiovascular Research Center, Division of Cardiology University of Rochester Medical Center Rochester NY USA
- Department of Medicine, Rochester Regional Health Rochester NY USA
| | - Arwa Younis
- Clinical Cardiovascular Research Center, Division of Cardiology University of Rochester Medical Center Rochester NY USA
- Department of Cardiovascular Medicine Cleveland Clinic Cleveland OH USA
| | - Anita Y Chen
- Department of Biostatistics and Computational Biology University of Rochester Medical Center Rochester NY USA
| | - David T Huang
- Department of Medicine, Division of Cardiology University of Rochester Medical Center Rochester NY USA
| | - Ayhan Yoruk
- Division of Cardiology The University of California, San Francisco Medical Center San Francisco CA USA
| | - Mehmet K Aktas
- Department of Medicine, Division of Cardiology University of Rochester Medical Center Rochester NY USA
| | - Spencer Rosero
- Department of Medicine, Division of Cardiology University of Rochester Medical Center Rochester NY USA
| | - Kristina Cutter
- Clinical Cardiovascular Research Center, Division of Cardiology University of Rochester Medical Center Rochester NY USA
| | - Scott McNitt
- Clinical Cardiovascular Research Center, Division of Cardiology University of Rochester Medical Center Rochester NY USA
| | - Nona Sotoodehnia
- Department of Medicine, Division of Cardiology University of Washington Seattle WA USA
| | | | - Thomas D Rea
- Department of Medicine University of Washington Seattle WA USA
| | - Dan E Arking
- The McKusick-Nathans Institute, Department of Genetic Medicine John Hopkins University School of Medicine Baltimore MD USA
| | - Wojciech Zareba
- Clinical Cardiovascular Research Center, Division of Cardiology University of Rochester Medical Center Rochester NY USA
| | - Michael J Ackerman
- Departments of Cardiovascular Medicine, Pediatric and Adolescent Medicine, and Molecular Pharmacology & Experimental Therapeutics, Divisions of Heart Rhythm Services and Pediatric Cardiology, Windland Smith Rice Genetic Heart Rhythm Clinic and Windland Smith Rice Sudden Death Genomics Laboratory Mayo Clinic Rochester MN USA
| | - Ilan Goldenberg
- Clinical Cardiovascular Research Center, Division of Cardiology University of Rochester Medical Center Rochester NY USA
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Badura K, Buławska D, Dąbek B, Witkowska A, Lisińska W, Radzioch E, Skwira S, Młynarska E, Rysz J, Franczyk B. Primary Electrical Heart Disease-Principles of Pathophysiology and Genetics. Int J Mol Sci 2024; 25:1826. [PMID: 38339103 PMCID: PMC10855675 DOI: 10.3390/ijms25031826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/27/2024] [Accepted: 01/28/2024] [Indexed: 02/12/2024] Open
Abstract
Primary electrical heart diseases, often considered channelopathies, are inherited genetic abnormalities of cardiomyocyte electrical behavior carrying the risk of malignant arrhythmias leading to sudden cardiac death (SCD). Approximately 54% of sudden, unexpected deaths in individuals under the age of 35 do not exhibit signs of structural heart disease during autopsy, suggesting the potential significance of channelopathies in this group of age. Channelopathies constitute a highly heterogenous group comprising various diseases such as long QT syndrome (LQTS), short QT syndrome (SQTS), idiopathic ventricular fibrillation (IVF), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and early repolarization syndromes (ERS). Although new advances in the diagnostic process of channelopathies have been made, the link between a disease and sudden cardiac death remains not fully explained. Evolving data in electrophysiology and genetic testing suggest previously described diseases as complex with multiple underlying genes and a high variety of factors associated with SCD in channelopathies. This review summarizes available, well-established information about channelopathy pathogenesis, genetic basics, and molecular aspects relative to principles of the pathophysiology of arrhythmia. In addition, general information about diagnostic approaches and management is presented. Analyzing principles of channelopathies and their underlying causes improves the understanding of genetic and molecular basics that may assist general research and improve SCD prevention.
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Affiliation(s)
- Krzysztof Badura
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
| | - Dominika Buławska
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
| | - Bartłomiej Dąbek
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
| | - Alicja Witkowska
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
| | - Wiktoria Lisińska
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
| | - Ewa Radzioch
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
| | - Sylwia Skwira
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
| | - Ewelina Młynarska
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
| | - Jacek Rysz
- Department of Nephrology, Hypertension and Family Medicine, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland
| | - Beata Franczyk
- Department of Nephrocardiology, Medical University of Lodz, Ul. Zeromskiego 113, 90-549 Lodz, Poland (S.S.)
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Asatryan B, Murray B, Gasperetti A, McClellan R, Barth AS. Unraveling Complexities in Genetically Elusive Long QT Syndrome. Circ Arrhythm Electrophysiol 2024; 17:e012356. [PMID: 38264885 DOI: 10.1161/circep.123.012356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Genetic testing has become standard of care for patients with long QT syndrome (LQTS), providing diagnostic, prognostic, and therapeutic information for both probands and their family members. However, up to a quarter of patients with LQTS do not have identifiable Mendelian pathogenic variants in the currently known LQTS-associated genes. This absence of genetic confirmation, intriguingly, does not lessen the severity of LQTS, with the prognosis in these gene-elusive patients with unequivocal LQTS mirroring genotype-positive patients in the limited data available. Such a conundrum instigates an exploration into the causes of corrected QT interval (QTc) prolongation in these cases, unveiling a broad spectrum of potential scenarios and mechanisms. These include multiple environmental influences on QTc prolongation, exercise-induced repolarization abnormalities, and the profound implications of the constantly evolving nature of genetic testing and variant interpretation. In addition, the rapid advances in genetics have the potential to uncover new causal genes, and polygenic risk factors may aid in the diagnosis of high-risk patients. Navigating this multifaceted landscape requires a systematic approach and expert knowledge, integrating the dynamic nature of genetics and patient-specific influences for accurate diagnosis, management, and counseling of patients. The role of a subspecialized expert cardiogenetic clinic is paramount in evaluation to navigate this complexity. Amid these intricate aspects, this review outlines potential causes of gene-elusive LQTS. It also provides an outline for the evaluation of patients with negative and inconclusive genetic test results and underscores the need for ongoing adaptation and reassessment in our understanding of LQTS, as the complexities of gene-elusive LQTS are increasingly deciphered.
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Affiliation(s)
- Babken Asatryan
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Brittney Murray
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Alessio Gasperetti
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Rebecca McClellan
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Andreas S Barth
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD
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Hellström Schmidt S, Smedenmark J, Jeremiasen I, Sigurdsson B, Eklund EA, Pronk CJ. Overuse of EEG and ECG in children with breath-holding spells and its implication for the management of the spells. Acta Paediatr 2024; 113:317-326. [PMID: 37905418 DOI: 10.1111/apa.17020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 10/15/2023] [Accepted: 10/19/2023] [Indexed: 11/02/2023]
Abstract
AIM Breath-holding spells (BHS) are common in children, but evidence-based clinical guidelines are lacking. We investigated a large population-based cohort of BHS patients, to propose a refined description of typical BHS and guidelines for its management. METHODS In a cross-sectional retrospective study, patients diagnosed with BHS in Southern Sweden 2004-2018 were recruited. Disease characteristics and diagnostic data were collected from patient medical records. RESULTS In total, 519 patients, mean age at diagnosis 19.8 ± 13.8 months with equal gender distribution, were included. In 48.3%, BHS had already been diagnosed after one spell. During spells, 78.0% of patients were unresponsive. For 71.5%, atonic, tonic, tonic-clonic or myoclonic seizures were reported, and 78.0% of patients had a spell lasting less than 1 min. Electroencephalography was conducted in 30.4% and Electrocardiography in 45.1%. Six children (3.8%) had a pathological electroencephalogram, four of which had concomitant epilepsy and only 0.9% of children had electrocardiogram findings suggesting pathology, none showing long QT syndrome. CONCLUSION Children with BHS were frequently subjected to unnecessary diagnostic interventions. We characterise a typical presentation of BHS and propose a management-algorithm, which is expected to reduce unnecessary usage of electroencephalography and electrocardiography.
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Affiliation(s)
- Sanna Hellström Schmidt
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
- Chilhood Cancer Center, Skåne University Hospital, Lund, Sweden
| | - Julia Smedenmark
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Ida Jeremiasen
- The Paediatric Heart Center, Skåne University Hospital, Lund, Sweden
| | - Björn Sigurdsson
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
- Department of Paediatric Neurology, Skåne University Hospital, Lund, Sweden
| | - Erik A Eklund
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
- Department of Paediatric Neurology, Skåne University Hospital, Lund, Sweden
| | - Cornelis Jan Pronk
- Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
- Chilhood Cancer Center, Skåne University Hospital, Lund, Sweden
- Wallenberg Centre Molecular Medicine and Division Molecular Haematology, Lund University, Lund, Sweden
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9
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Shauer A, Horowitz-Cederboim S, Mor-Shaked H, Durst R, Zwas DR, Belhassen B. Calmodulinopathy Associated Long QT Syndrome, Hypertrophic Cardiomyopathy With Excessive Trabeculation in a 14-Year-Old Girl Presenting With Ventricular Fibrillation. Circ Genom Precis Med 2024; 17:e004163. [PMID: 38258601 DOI: 10.1161/circgen.123.004163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Affiliation(s)
- Ayelet Shauer
- Heart Institute (A.S., S.H.-C., R.D., D.R.Z., B.B.), Hadassah Medical Center, Jerusalem, Israel
- Faculty of Medicine, Hebrew University of Jerusalem, Israel (A.S., H.M.-S., R.D., D.R.Z.)
| | | | - Hagar Mor-Shaked
- Department of Genetics (H.M.-S.), Hadassah Medical Center, Jerusalem, Israel
- Faculty of Medicine, Hebrew University of Jerusalem, Israel (A.S., H.M.-S., R.D., D.R.Z.)
| | - Ronen Durst
- Heart Institute (A.S., S.H.-C., R.D., D.R.Z., B.B.), Hadassah Medical Center, Jerusalem, Israel
- Faculty of Medicine, Hebrew University of Jerusalem, Israel (A.S., H.M.-S., R.D., D.R.Z.)
| | - Donna R Zwas
- Heart Institute (A.S., S.H.-C., R.D., D.R.Z., B.B.), Hadassah Medical Center, Jerusalem, Israel
- Faculty of Medicine, Hebrew University of Jerusalem, Israel (A.S., H.M.-S., R.D., D.R.Z.)
| | - Bernard Belhassen
- Heart Institute (A.S., S.H.-C., R.D., D.R.Z., B.B.), Hadassah Medical Center, Jerusalem, Israel
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Vătășescu RG, Deaconu S, Iorgulescu CN, Marascu G, Oprita B, Deaconu A. Long QT Syndrome and WPW Syndrome: A Very Rare Association between Two Causes of Sudden Cardiac Death in a Young Patient. J Clin Med 2024; 13:804. [PMID: 38337498 PMCID: PMC10856791 DOI: 10.3390/jcm13030804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 01/22/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024] Open
Abstract
Long QT syndrome (LQT) and WPW syndrome are causes of sudden cardiac death (SCD) in the young, and their association has been rarely reported. A 26-year-old woman presented with recurrent syncope. Her ECG showed a short PR interval, wide QRS (150 ms) due to a delta wave, and QT prolongation (QT 580 ms, QTc 648 ms). ECG monitoring documented recurrent salvos of a self-terminating wide QRS tachycardia, generally slightly polymorphic, sometimes with "torsade des pointes" (TdP) appearance, which were linked to the syncopal/presyncope episodes. Electrophysiologic monitoring diagnosed a right para-hisian accessory pathway with a very short ERP (240 ms baseline, <200 ms after isoproterenol). The pathway was ablated successfully. Despite QRS narrowing (80 ms), QT prolongation persisted after ablation (QT 620 ms, QTc 654 ms), with short runs of TdP, despite beta-blocker treatment, which was increased to the maximal dosage. A dual-chamber implantable cardioverter defibrillator (ICD) was implanted. To our knowledge, this is the first case report of an association between LQT and WPW syndrome in which both conditions are associated with an increased risk of SCD.
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Affiliation(s)
- Radu Gabriel Vătășescu
- Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania;
- Cardiology Department, Clinical Emergency Hospital, 014461 Bucharest, Romania; (C.N.I.); (G.M.)
| | | | | | - Gabriela Marascu
- Cardiology Department, Clinical Emergency Hospital, 014461 Bucharest, Romania; (C.N.I.); (G.M.)
| | - Bogdan Oprita
- Emergency Department, Clinical Emergency Hospital, 014461 Bucharest, Romania;
| | - Alexandru Deaconu
- Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania;
- Cardiology Department, Clinical Emergency Hospital, 014461 Bucharest, Romania; (C.N.I.); (G.M.)
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11
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Qi M, Ma S, Liu J, Liu X, Wei J, Lu WJ, Zhang S, Chang Y, Zhang Y, Zhong K, Yan Y, Zhu M, Song Y, Chen Y, Hao G, Wang J, Wang L, Lee AS, Chen X, Wang Y, Lan F. In Vivo Base Editing of Scn5a Rescues Type 3 Long QT Syndrome in Mice. Circulation 2024; 149:317-329. [PMID: 37965733 DOI: 10.1161/circulationaha.123.065624] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 10/17/2023] [Indexed: 11/16/2023]
Abstract
BACKGROUND Pathogenic variants in SCN5A can result in long QT syndrome type 3, a life-threatening genetic disease. Adenine base editors can convert targeted A T base pairs to G C base pairs, offering a promising tool to correct pathogenic variants. METHODS We generated a long QT syndrome type 3 mouse model by introducing the T1307M pathogenic variant into the Scn5a gene. The adenine base editor was split into 2 smaller parts and delivered into the heart by adeno-associated virus serotype 9 (AAV9-ABEmax) to correct the T1307M pathogenic variant. RESULTS Both homozygous and heterozygous T1307M mice showed significant QT prolongation. Carbachol administration induced Torsades de Pointes or ventricular tachycardia for homozygous T1307M mice (20%) but not for heterozygous or wild-type mice. A single intraperitoneal injection of AAV9-ABEmax at postnatal day 14 resulted in up to 99.20% Scn5a transcripts corrected in T1307M mice. Scn5a mRNA correction rate >60% eliminated QT prolongation; Scn5a mRNA correction rate <60% alleviated QT prolongation. Partial Scn5a correction resulted in cardiomyocytes heterogeneity, which did not induce severe arrhythmias. We did not detect off-target DNA or RNA editing events in ABEmax-treated mouse hearts. CONCLUSIONS These findings show that in vivo AAV9-ABEmax editing can correct the variant Scn5a allele, effectively ameliorating arrhythmia phenotypes. Our results offer a proof of concept for the treatment of hereditary arrhythmias.
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Affiliation(s)
- Man Qi
- Shenzhen Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences, Fuwai Hospital, Shenzhen, China (M.Q., S.M., X.L., Y. Chang, Y.Z., Y.Y., M.Z., L.W.)
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
- Chinese PLA General Hospital, College of Pulmonary & Critical Care Medicine, Beijing Key Laboratory of OTIR, Beijing, China (M.Q.)
- Department of Cardiology, Chinese PLA General Hospital, Beijing, China (M.Q., Y. Chen)
| | - Shuhong Ma
- Shenzhen Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences, Fuwai Hospital, Shenzhen, China (M.Q., S.M., X.L., Y. Chang, Y.Z., Y.Y., M.Z., L.W.)
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
| | - Jingtong Liu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, China (J.L., Y.W.)
| | - Xujie Liu
- Shenzhen Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences, Fuwai Hospital, Shenzhen, China (M.Q., S.M., X.L., Y. Chang, Y.Z., Y.Y., M.Z., L.W.)
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Fuwai Central-China Hospital, Central-China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China (X.L., F.L.)
| | - Jingjing Wei
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
| | - Wen-Jing Lu
- Beijing Laboratory for Cardiovascular Precision Medicine, The Key Laboratory of Biomedical Engineering for Cardiovascular Disease Research, Ministry of Education, Beijing Anzhen Hospital, Capital Medical University, Beijing, China (W.-J.L., S.Z., F.L.)
| | - Siyao Zhang
- Beijing Laboratory for Cardiovascular Precision Medicine, The Key Laboratory of Biomedical Engineering for Cardiovascular Disease Research, Ministry of Education, Beijing Anzhen Hospital, Capital Medical University, Beijing, China (W.-J.L., S.Z., F.L.)
| | - Yun Chang
- Shenzhen Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences, Fuwai Hospital, Shenzhen, China (M.Q., S.M., X.L., Y. Chang, Y.Z., Y.Y., M.Z., L.W.)
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
| | - Yongshuai Zhang
- Shenzhen Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences, Fuwai Hospital, Shenzhen, China (M.Q., S.M., X.L., Y. Chang, Y.Z., Y.Y., M.Z., L.W.)
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
| | - Kejia Zhong
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
| | - Yuting Yan
- Shenzhen Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences, Fuwai Hospital, Shenzhen, China (M.Q., S.M., X.L., Y. Chang, Y.Z., Y.Y., M.Z., L.W.)
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
| | - Min Zhu
- Shenzhen Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences, Fuwai Hospital, Shenzhen, China (M.Q., S.M., X.L., Y. Chang, Y.Z., Y.Y., M.Z., L.W.)
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
| | - Yabing Song
- School of Life Sciences, Tsinghua University, Beijing, China (Y.S., J. Wang)
| | - Yundai Chen
- Department of Cardiology, Chinese PLA General Hospital, Beijing, China (M.Q., Y. Chen)
| | - Guoliang Hao
- Henan Academy of Innovations in Medical Science, Zhengzhou, China (G.H.)
| | - Jianbin Wang
- School of Life Sciences, Tsinghua University, Beijing, China (Y.S., J. Wang)
| | - Li Wang
- Shenzhen Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences, Fuwai Hospital, Shenzhen, China (M.Q., S.M., X.L., Y. Chang, Y.Z., Y.Y., M.Z., L.W.)
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
| | - Andrew S Lee
- Institute for Cancer Research, Shenzhen Bay Laboratory, Shenzhen, China (A.S.L.)
| | - Xiangbo Chen
- Hangzhou Rongze Biotechnology Group Co, Ltd, Hangzhou, China (X.C.)
| | - Yongming Wang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, China (J.L., Y.W.)
| | - Feng Lan
- Key Laboratory of Pluripotent Stem Cells in Cardiac Repair and Regeneration, State Key Laboratory of Cardiovascular Disease, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China (M.Q., S.M., X.L., J. Wei, Y. Chang, Y.Z., K.Z., Y.Y., M.Z., L.W., F.L.)
- National Health Commission Key Laboratory of Cardiovascular Regenerative Medicine, Fuwai Central-China Hospital, Central-China Branch of National Center for Cardiovascular Diseases, Zhengzhou, China (X.L., F.L.)
- Beijing Laboratory for Cardiovascular Precision Medicine, The Key Laboratory of Biomedical Engineering for Cardiovascular Disease Research, Ministry of Education, Beijing Anzhen Hospital, Capital Medical University, Beijing, China (W.-J.L., S.Z., F.L.)
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12
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González-Garrido A, López-Ramírez O, Cerda-Mireles A, Navarrete-Miranda T, Flores-Arenas AI, Rojo-Domínguez A, Arregui L, Iturralde P, Antúnez-Argüelles E, Domínguez-Pérez M, Jacobo-Albavera L, Carnevale A, Villarreal-Molina T. KCNQ1 p.D446E Variant as a Risk Allele for Arrhythmogenic Phenotypes: Electrophysiological Characterization Reveals a Complex Phenotype Affecting the Slow Delayed Rectifier Potassium Current (IKs) Voltage Dependence by Causing a Hyperpolarizing Shift and a Lack of Response to Protein Kinase A Activation. Int J Mol Sci 2024; 25:953. [PMID: 38256028 PMCID: PMC10816087 DOI: 10.3390/ijms25020953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/05/2024] [Accepted: 01/07/2024] [Indexed: 01/24/2024] Open
Abstract
Genetic testing is crucial in inherited arrhythmogenic channelopathies; however, the clinical interpretation of genetic variants remains challenging. Incomplete penetrance, oligogenic, polygenic or multifactorial forms of channelopathies further complicate variant interpretation. We identified the KCNQ1/p.D446E variant in 2/63 patients with long QT syndrome, 30-fold more frequent than in public databases. We thus characterized the biophysical phenotypes of wildtype and mutant IKs co-expressing these alleles with the β-subunit minK in HEK293 cells. KCNQ1 p.446E homozygosity significantly shifted IKs voltage dependence to hyperpolarizing potentials in basal conditions (gain of function) but failed to shift voltage dependence to hyperpolarizing potentials (loss of function) in the presence of 8Br-cAMP, a protein kinase A activator. Basal IKs activation kinetics did not differ among genotypes, but in response to 8Br-cAMP, IKs 446 E/E (homozygous) activation kinetics were slower at the most positive potentials. Protein modeling predicted a slower transition of the 446E Kv7.1 tetrameric channel to the stabilized open state. In conclusion, biophysical and modelling evidence shows that the KCNQ1 p.D446E variant has complex functional consequences including both gain and loss of function, suggesting a contribution to the pathogenesis of arrhythmogenic phenotypes as a functional risk allele.
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Affiliation(s)
- Antonia González-Garrido
- Laboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico; (A.G.-G.); (A.C.-M.); (T.N.-M.); (A.I.F.-A.); (A.C.)
| | - Omar López-Ramírez
- Instituto de Oftalmología Fundación de Asistencia Privada Conde de la Valenciana, I.A.P., Mexico City 06800, Mexico;
| | - Abel Cerda-Mireles
- Laboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico; (A.G.-G.); (A.C.-M.); (T.N.-M.); (A.I.F.-A.); (A.C.)
| | - Thania Navarrete-Miranda
- Laboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico; (A.G.-G.); (A.C.-M.); (T.N.-M.); (A.I.F.-A.); (A.C.)
| | - Aranza Iztanami Flores-Arenas
- Laboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico; (A.G.-G.); (A.C.-M.); (T.N.-M.); (A.I.F.-A.); (A.C.)
| | - Arturo Rojo-Domínguez
- Departamento de Ciencias Naturales, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Mexico City 05348, Mexico; (A.R.-D.); (L.A.)
| | - Leticia Arregui
- Departamento de Ciencias Naturales, Universidad Autónoma Metropolitana, Unidad Cuajimalpa, Mexico City 05348, Mexico; (A.R.-D.); (L.A.)
| | - Pedro Iturralde
- Departamento de Electrofisiología, Instituto Nacional de Cardiología “Ignacio Chávez”, Mexico City 14080, Mexico;
| | | | - Mayra Domínguez-Pérez
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico; (M.D.-P.); (L.J.-A.)
| | - Leonor Jacobo-Albavera
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico; (M.D.-P.); (L.J.-A.)
| | - Alessandra Carnevale
- Laboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico; (A.G.-G.); (A.C.-M.); (T.N.-M.); (A.I.F.-A.); (A.C.)
| | - Teresa Villarreal-Molina
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica (INMEGEN), Mexico City 14610, Mexico; (M.D.-P.); (L.J.-A.)
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13
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Kis L, Li J. Proof of concept for monoclonal antibody therapy in a cellular model of acquired long QT syndrome type 3. Am J Physiol Heart Circ Physiol 2024; 326:H89-H95. [PMID: 37947435 DOI: 10.1152/ajpheart.00628.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023]
Abstract
Long QT syndrome (LQTS) type 3 although less common than the first two forms, differs in that arrhythmic events are less likely triggered by adrenergic stimuli and are more often lethal. Effective pharmacological treatment is challenged by interindividual differences, mutation dependence, and adverse effects, translating into an increased use of invasive measures (implantable cardioverter-defibrillator, sympathetic denervation) in patients with LQTS type 3. Previous studies have demonstrated the therapeutic potential of polyclonal KCNQ1 antibody for LQTS type 2. Here, we sought to identify a monoclonal KCNQ1 antibody that preserves the electrophysiological properties of the polyclonal form. Using hybridoma technology, murine monoclonal antibodies were generated, and patch clamp studies were performed for functional characterization. We identified a monoclonal KCNQ1 antibody able to normalize cardiac action potential duration and to suppress arrhythmias in a pharmacological model of LQTS type 3 using human-induced pluripotent stem cell-derived cardiomyocytes.NEW & NOTEWORTHY Long QT syndrome is a leading cause of sudden cardiac death in the young. Recent research has highlighted KCNQ1 antibody therapy as a new treatment modality for long QT syndrome type 2. Here, we developed a monoclonal KCNQ1 antibody that similarly restores cardiac repolarization. Moreover, the identified monoclonal KCNQ1 antibody suppresses arrhythmias in a cellular model of long QT syndrome type 3, holding promise as a first-in-class antiarrhythmic immunotherapy.
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Affiliation(s)
- Lenke Kis
- Center for Translational and Experimental Cardiology, Department of Cardiology, University of Zurich, Zurich, Switzerland
| | - Jin Li
- Center for Translational and Experimental Cardiology, Department of Cardiology, University of Zurich, Zurich, Switzerland
- Department of Cardiology, University Heart Center, University Hospital Zurich, Zurich, Switzerland
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14
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Hu W, Zhang W, Zhang K, Al-Moubarak E, Zhang Y, Harmer SC, Hancox JC, Zhang H. Evaluating pro-arrhythmogenic effects of the T634S-hERG mutation: insights from a simulation study. Interface Focus 2023; 13:20230035. [PMID: 38106919 PMCID: PMC10722218 DOI: 10.1098/rsfs.2023.0035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 11/06/2023] [Indexed: 12/19/2023] Open
Abstract
A mutation to serine of a conserved threonine (T634S) in the hERG K+ channel S6 pore region has been identified as a variant of uncertain significance, showing a loss-of-function effect. However, its potential consequences for ventricular excitation and arrhythmogenesis have not been reported. This study evaluated possible functional effects of the T634S-hERG mutation on ventricular excitation and arrhythmogenesis by using multi-scale computer models of the human ventricle. A Markov chain model of the rapid delayed rectifier potassium current (IKr) was reconstructed for wild-type and T634S-hERG mutant conditions and incorporated into the ten Tusscher et al. models of human ventricles at cell and tissue (1D, 2D and 3D) levels. Possible functional impacts of the T634S-hERG mutation were evaluated by its effects on action potential durations (APDs) and their rate-dependence (APDr) at the cell level; and on the QT interval of pseudo-ECGs, tissue vulnerability to unidirectional conduction block (VW), spiral wave dynamics and repolarization dispersion at the tissue level. It was found that the T634S-hERG mutation prolonged cellular APDs, steepened APDr, prolonged the QT interval, increased VW, destablized re-entry and augmented repolarization dispersion across the ventricle. Collectively, these results imply potential pro-arrhythmic effects of the T634S-hERG mutation, consistent with LQT2.
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Affiliation(s)
- Wei Hu
- Biological Physics Group, Department of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK
| | - Wenfeng Zhang
- College of Computer and Information Science, Chongqing Normal University, Chongqing, People's Republic of China
| | - Kevin Zhang
- Southmead Hospital, North Bristol Trust, Bristol, UK
| | - Ehab Al-Moubarak
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Yihong Zhang
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Stephen C. Harmer
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Jules C. Hancox
- Biological Physics Group, Department of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD, UK
| | - Henggui Zhang
- Biological Physics Group, Department of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK
- Key Laboratory of Medical Electrophysiology of Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, Luzhou 646000, People's Republic of China
- Beijing Academy of Artificial Intelligence, Beijing 100084, People's Republic of China
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15
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Nuttall GA, Reed AM, Pham Louis KD, Oyen LJ, Marsland SP, Ackerman MJ. The Incidence of Torsades de Pointes With Perioperative Triple Antiemetic Administration. Ann Pharmacother 2023:10600280231215786. [PMID: 38053391 DOI: 10.1177/10600280231215786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023] Open
Abstract
BACKGROUND The safety of triple antiemetic therapy consisting of ondansetron, haloperidol, and a steroid, to surgical patients is unknown. OBJECTIVE To determine the incidence of torsade de pointes (TdP) or death following perioperative administration of triple antiemetic therapy. METHODS A retrospective cohort study identified 19,874 patients who received 22,202 doses of triple antiemetics during the 2.5-year time frame from March 4, 2020 to September 7, 2022 for surgical nausea prophylaxis or treatment of nausea. These patients above were cross-matched with an electrocardiogram and adverse outcome database; this identified 226 patients with documentation of a QTc > 450 ms, all ventricular tachycardias including TdP within 48 hours of receiving triple antiemetic therapy, or death within 7 days of receiving ondansetron. RESULTS There were 3 patients who had documented VT (n = 3), but there were no documented incidents of TdP (n = 0). There were 9 codes called on patients within 48 hours of medication administration, and none of them were due to ventricular arrythmias (n = 0). A total of 11 patients died within 7 days of triple antiemetic therapy. Ten of the 11 deaths were determined to not be from the triple antiemetic. One patient died at home within 24 hours of the procedure of an unknown cause (n = 1). CONCLUSIONS AND RELEVANCE No episodes of TdP were identified in patients receiving triple antiemetic therapy perioperatively, though the cause of death in 1 patient could not be determined. This suggest that low-dose triple antiemetic therapy is low risk for the development of TdP.
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Affiliation(s)
- Gregory A Nuttall
- Department of Anesthesiology, Mayo Clinic College of Medicine and Science, Mayo Foundation, Rochester, MN, USA
| | - Alyssa M Reed
- Mayo School of Health Sciences, Mayo Foundation, Rochester, MN, USA
| | | | - Lance J Oyen
- Mayo Clinic College of Medicine and Science, Mayo Foundation, Rochester, MN, USA
| | | | - Michael J Ackerman
- Mayo Clinic College of Medicine and Science, Mayo Foundation, Rochester, MN, USA
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16
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Albertini L, Ezekian J, Care M, Silversides C, Sermer M, Gollob MH, Spears D. Assessment of Severity of Long QT Syndrome Phenotype and Risk of Fetal Death. J Am Heart Assoc 2023; 12:e029407. [PMID: 38014677 PMCID: PMC10727344 DOI: 10.1161/jaha.122.029407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 10/30/2023] [Indexed: 11/29/2023]
Abstract
BACKGROUND It has been postulated that long QT syndrome (LQTS) can cause fetal loss through putative adverse effects of the channelopathy on placenta and myometrial function. The authors aimed to describe the fetal death rate in a population of pregnant women with long QT syndrome and investigate whether women with more severe phenotype had worse fetal outcomes. METHODS AND RESULTS The authors retrospectively evaluated fetal outcomes of 64 pregnancies from 23 women with long QT syndrome followed during pregnancy in a tertiary pregnancy and heart disease program. Thirteen of 64 pregnancies (20%) resulted in a fetal loss, 12 miscarriages (19%), and 1 stillbirth (1.6%). Baseline maternal characteristics, including age and use of β-blockers, did not differ between women who experienced a fetal death or not. Maternal corrected QT interval (QTc) was significantly longer in pregnancies that resulted in fetal death compared with live births (median, 518 ms [interquartile range (IQR), 482-519 ms] versus 479 ms [IQR, 454-496 ms], P<0.001). Mothers treated with β-blockers had babies born at term with lower birth weight compared with untreated women (2973±298 g versus 3470±338 g, P=0.002). In addition, the birth weight of babies born at term to treated women with QTc >500 ms was significantly lower compared with women with QTc <500 ms (2783±283 g versus 3084±256 g, P=0.029). CONCLUSIONS Women with long QT syndrome with more severe phenotypes have a higher incidence of fetal death. Maternal QTc is longer in pregnancies that result in fetal loss, and the birth weight of babies born to patients taking β-blockers with a QTc >500 ms is lower, suggesting that patients with more marked phenotype may experience worse fetal outcomes.
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Affiliation(s)
- Lisa Albertini
- Division of Cardiology, Electrophysiology, Toronto General HospitalUniversity Health Network TorontoTorontoOntarioCanada
| | - Jordan Ezekian
- Division of CardiologyThe Hospital for Sick ChildrenTorontoOntarioCanada
| | - Melanie Care
- Division of Cardiology, Electrophysiology, Toronto General HospitalUniversity Health Network TorontoTorontoOntarioCanada
| | - Candice Silversides
- Department of Medicine, Division of CardiologyUniversity of Toronto Pregnancy and Heart Disease Program and Obstetric Medicine Program, Mount Sinai and Toronto General HospitalsTorontoOntarioCanada
| | - Mathew Sermer
- Department of Obstetrics and GynaecologyMount Sinai HospitalTorontoOntarioCanada
| | - Michael H. Gollob
- Division of Cardiology, Electrophysiology, Toronto General HospitalUniversity Health Network TorontoTorontoOntarioCanada
| | - Danna Spears
- Division of Cardiology, Electrophysiology, Toronto General HospitalUniversity Health Network TorontoTorontoOntarioCanada
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17
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Dahlberg P, Axelsson KJ, Rydberg A, Lundahl G, Gransberg L, Bergfeldt L. Spatiotemporal repolarization dispersion before and after exercise in patients with long QT syndrome type 1 versus controls: probing into the arrhythmia substrate. Am J Physiol Heart Circ Physiol 2023; 325:H1279-H1289. [PMID: 37773058 DOI: 10.1152/ajpheart.00335.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 09/21/2023] [Accepted: 09/22/2023] [Indexed: 09/30/2023]
Abstract
Congenital long QT syndrome (LQTS) carries an increased risk for syncope and sudden death. QT prolongation promotes ventricular extrasystoles, which, in the presence of an arrhythmia substrate, might trigger ventricular tachycardia degenerating into fibrillation. Increased electrical heterogeneity (dispersion) is the suggested arrhythmia substrate in LQTS. In the most common subtype LQT1, physical exercise predisposes for arrhythmia and spatiotemporal dispersion was therefore studied in this context. Thirty-seven patients (57% on β-blockers) and 37 healthy controls (mean age, 31 vs. 35; range, 6-68 vs. 6-72 yr) performed an exercise test. Frank vectorcardiography was used to assess spatiotemporal dispersion as Tampl, Tarea, the ventricular gradient (VG), and the Tpeak-end interval from 10-s signal averages before and 7 ± 2 min after exercise; during exercise too much signal disturbance excluded analysis. Baseline and maximum heart rates as well as estimated exercise intensity were similar, but heart rate recovery was slower in patients. At baseline, QT and heart rate-corrected QT (QTcB) were significantly longer in patients (as expected), whereas dispersion parameters were numerically larger in controls. After exercise, QTpeakcB and Tpeak-endcB increased significantly more in patients (18 ± 23 vs. 7 ± 10 ms and 12 ± 17 vs. 2 ± 6 ms; P < 0.001 and P < 0.01). There was, however, no difference in the change in Tampl, Tarea, and VG between groups. In conclusion, although temporal dispersion of repolarization increased significantly more after exercise in patients with LQT1, there were no signs of exercise-induced increase in global dispersion of action potential duration and morphology. The arrhythmia substrate/mechanism in LQT1 warrants further study.NEW & NOTEWORTHY Physical activity increases the risk for life-threatening arrhythmias in LQTS type 1 (LQT1). The arrhythmia substrate is presumably altered electrical heterogeneity (a.k.a. dispersion). Spatiotemporal dispersion parameters were therefore compared before and after exercise in patients versus healthy controls using Frank vectorcardiography, a novelty. Physical exercise prolonged the time between the earliest and latest complete repolarization in patients versus controls, but did not increase parameters reflecting global dispersion of action potential duration and morphology, another novelty.
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Affiliation(s)
- Pia Dahlberg
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Region Vaestra Goetaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Karl-Jonas Axelsson
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Region Vaestra Goetaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Annika Rydberg
- Division of Pediatrics, Department of Clinical Sciences, Umeå University, Umeå, Sweden
| | - Gunilla Lundahl
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lennart Gransberg
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lennart Bergfeldt
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Region Vaestra Goetaland, Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
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Abstract
Calcium ions (Ca2+) are the basis of a unique and potent array of cellular responses. Calmodulin (CaM) is a small but vital protein that is able to rapidly transmit information about changes in Ca2+ concentrations to its regulatory targets. CaM plays a critical role in cellular Ca2+ signaling, and interacts with a myriad of target proteins. Ca2+-dependent modulation by CaM is a major component of a diverse array of processes, ranging from gene expression in neurons to the shaping of the cardiac action potential in heart cells. Furthermore, the protein sequence of CaM is highly evolutionarily conserved, and identical CaM proteins are encoded by three independent genes (CALM1-3) in humans. Mutations within any of these three genes may lead to severe cardiac deficits including severe long QT syndrome (LQTS) and/or catecholaminergic polymorphic ventricular tachycardia (CPVT). Research into disease-associated CaM variants has identified several proteins modulated by CaM that are likely to underlie the pathogenesis of these calmodulinopathies, including the cardiac L-type Ca2+ channel (LTCC) CaV1.2, and the sarcoplasmic reticulum Ca2+ release channel, ryanodine receptor 2 (RyR2). Here, we review the research that has been done to identify calmodulinopathic CaM mutations and evaluate the mechanisms underlying their role in disease.
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Affiliation(s)
- John W. Hussey
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Worawan B. Limpitikul
- Department of Medicine, Division of Cardiology, Massachusetts General Hospital, Boston, MA, USA
| | - Ivy E. Dick
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- CONTACT Ivy E. Dick School of Medicine, University of Maryland, Baltimore, MD21210
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Akturk G, Micili SC, Gursoy Doruk O, Hocaoglu N, Akan P, Ergur BU, Ahmed S, Kalkan S. Effects of nicorandil on QT prolongation and myocardial damage caused by citalopram in rats. Biotech Histochem 2023; 98:479-491. [PMID: 37466068 DOI: 10.1080/10520295.2023.2233417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023] Open
Abstract
Citalopram is a selective serotonin re-uptake inhibitor (SSRI) antidepressant; it exhibits the greatest cardiotoxic effect among SSRIs. Citalopram can cause drug-induced long QT syndrome (LQTS) and ventricular arrhythmias. We investigated the protective effect of nicorandil, a selective mitochondrial KATP (mito-KATP) channel opener, on LQTS and myocardial damage caused by citalopram in male rats. In a preliminary study, we determined that the minimum citalopram dose that prolonged the QT interval was 102 mg/kg injected intraperitoneally. For the main study, rats were divided randomly into five experimental groups: untreated control, normal saline + citalopram, nicorandil + citalopram, 5-hydroxydecanoate (5-HD) + citalopram, 5-HD + nicorandil + citalopram. Biochemical and histologic data from blood and heart tissue samples from six untreated control rats were evaluated. Electrocardiographic parameters including QRS duration, QT interval, corrected QT interval (QTc) and heart rate (HR) were assessed, and biochemical parameters including malondialdehyde, reduced glutathione, glutathione peroxidase, superoxide dismutase were measured. We also performed histomorphologic and immunohistochemical examination of heart tissue. Citalopram prolonged QT-QTc intervals significantly and increased significantly the histomorphologic score and proportion of apoptotic cells, but produced no differences in the oxidant and antioxidant parameters. Nicorandil did not prevent citalopram induced QT-QTc interval prolongation and produced no significant changes in oxidant and antioxidant parameters; however, it did reduce histologic damage and apoptosis caused by citalopram.
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Affiliation(s)
- Gozde Akturk
- Department of Medical Pharmacology, Dokuz Eylul University School of Medicine, Izmir, Turkey
- Department of Medical Pharmacology, Mustafa Kemal University School of Medicine, Hatay, Turkey
| | - Serap Cilaker Micili
- Department of Histology and Embryology, Dokuz Eylul University School of Medicine, Izmir, Turkey
| | - Ozlem Gursoy Doruk
- Department of Medical Biochemistry, Dokuz Eylul University School of Medicine, Izmir, Turkey
| | - Nil Hocaoglu
- Department of Medical Pharmacology, Dokuz Eylul University School of Medicine, Izmir, Turkey
| | - Pinar Akan
- Department of Medical Biochemistry, Dokuz Eylul University School of Medicine, Izmir, Turkey
| | - Bekir Ugur Ergur
- Department of Histology and Embryology, Dokuz Eylul University School of Medicine, Izmir, Turkey
- Department of Histology and Embryology, Kyrenia University School of Medicine, Kyrenia, Cyprus
| | - Samar Ahmed
- Department of Biochemistry, Dokuz Eylul University Graduate School of Health Sciences, Izmir, Turkey
| | - Sule Kalkan
- Department of Medical Pharmacology, Dokuz Eylul University School of Medicine, Izmir, Turkey
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Olleik F, Kamareddine MH, Spears J, Tse G, Liu T, Yan GX. Mexiletine: Antiarrhythmic mechanisms, emerging clinical applications and mortality. Pacing Clin Electrophysiol 2023; 46:1348-1356. [PMID: 37846818 DOI: 10.1111/pace.14846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 09/19/2023] [Accepted: 10/07/2023] [Indexed: 10/18/2023]
Abstract
Mexiletine, a class Ib antiarrhythmic drug, exhibits its major antiarrhythmic effect via inhibition of the fast and late Na+ currents in myocardial tissues that are dependent on the opening of Na+ channels for their excitation. Through a comprehensive examination of mexiletine's therapeutic benefits and potential risks, we aim to provide valuable insights that reinforce its role as a vital therapeutic option for patients with ventricular arrhythmias, long QT syndrome, and other heart rhythm disorders. This review will highlight the current understandings of the antiarrhythmic effects and rationales for recent off-label use and address the mortality and proarrhythmic effects of mexiletine utilizing published basic and clinical studies over the past five decades.
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Affiliation(s)
- Farah Olleik
- Lankenau Medical Center and Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA
| | | | - Jenna Spears
- Lankenau Medical Center and Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA
| | - Gary Tse
- Tianjin Key Laboratory of Ion-Molecular Function of Cardiovascular Disease, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, PR China
- Kent and Medway Medical School, Canterbury, Kent, UK
- School of Nursing and Health Studies, Hong Kong Metropolitan University, Hong Kong, PR China
| | - Tong Liu
- Tianjin Key Laboratory of Ion-Molecular Function of Cardiovascular Disease, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, PR China
| | - Gan-Xin Yan
- Lankenau Medical Center and Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA
- Fuwai Huazhong Hospital, Chinese Academy of Medical Sciences, Zhengzhou, PR China
- Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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21
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Longoni M, Bhasin K, Ward A, Lee D, Nisson M, Bhatt S, Rodriguez F, Dash R. Real-world utilization of guideline-directed genetic testing in inherited cardiovascular diseases. Front Cardiovasc Med 2023; 10:1272433. [PMID: 37915745 PMCID: PMC10616303 DOI: 10.3389/fcvm.2023.1272433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 09/29/2023] [Indexed: 11/03/2023] Open
Abstract
Background Cardiovascular disease continues to be the leading cause of death globally. Clinical practice guidelines aimed at improving disease management and positively impacting major cardiac adverse events recommend genetic testing for inherited cardiovascular conditions such as dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), long QT syndrome (LQTS), hereditary amyloidosis, and familial hypercholesterolemia (FH); however, little is known about how consistently practitioners order genetic testing for these conditions in routine clinical practice. This study aimed to assess the adoption of guideline-directed genetic testing for patients diagnosed with DCM, HCM, LQTS, hereditary amyloidosis, or FH. Methods This retrospective cohort study captured real-world evidence of genetic testing from ICD-9-CM and ICD-10-CM codes, procedure codes, and structured text fields of de-identified patient records in the Veradigm Health Insights Ambulatory EHR Research Database linked with insurance claims data. Data analysis was conducted using an automated electronic health record analysis engine. Patient records in the Veradigm database were sourced from more than 250,000 clinicians serving over 170 million patients in outpatient primary care and specialty practice settings in the United States and linked insurance claims data from public and private insurance providers. The primary outcome measure was evidence of genetic testing within six months of condition diagnosis. Results Between January 1, 2017, and December 31, 2021, 224,641 patients were newly diagnosed with DCM, HCM, LQTS, hereditary amyloidosis, or FH and included in this study. Substantial genetic testing care gaps were identified. Only a small percentage of patients newly diagnosed with DCM (827/101,919; 0.8%), HCM (253/15,507; 1.6%), LQTS (650/56,539; 1.2%), hereditary amyloidosis (62/1,026; 6.0%), or FH (718/49,650; 1.5%) received genetic testing. Conclusions Genetic testing is underutilized across multiple inherited cardiovascular conditions. This real-world data analysis provides insights into the delivery of genomic healthcare in the United States and suggests genetic testing guidelines are rarely followed in practice.
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Affiliation(s)
- Mauro Longoni
- Global Medical Affairs Organization, Illumina, Inc., San Diego, CA, United States
| | | | | | | | | | - Sucheta Bhatt
- Global Medical Affairs Organization, Illumina, Inc., San Diego, CA, United States
| | - Fatima Rodriguez
- HealthPals Inc., Redwood, CA, United States
- Division of Cardiovascular Medicine and Cardiovascular Institute, Stanford University, Stanford, CA, United States
| | - Rajesh Dash
- HealthPals Inc., Redwood, CA, United States
- Division of Cardiovascular Medicine and Cardiovascular Institute, Stanford University, Stanford, CA, United States
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Bhattacharya D, Namboodiri N, Sreelekshmi MP, Prabhu MA, Sreevilasam Pushpangadhan A, Menon S, Dharan BS, Valaparambil A. Left cardiac sympathetic denervation in children with Jervell Lange-Nielsen syndrome and drug refractory torsades - A case series. Pacing Clin Electrophysiol 2023; 46:1197-1202. [PMID: 37728293 DOI: 10.1111/pace.14827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 08/30/2023] [Accepted: 09/05/2023] [Indexed: 09/21/2023]
Abstract
INTRODUCTION Long QT syndrome is an inherited malignant channelopathy which leads to life-threatening arrhythmia, with multiple genotypes. Jervell and Lange-Nielsen syndrome (JLNS) is an autosomal recessive subtype of this disease, characterized by congenital sensorineural deafness and a high incidence of sudden cardiac death (SCD). METHODOLOGY We prospectively followed up six children who underwent left cardiac sympathetic denervation (LCSD) for JLNS in view of high-risk features despite being on maximally tolerated doses of oral propranolol. RESULTS Mean age at diagnosis was 2.75 ± 0.39 years, with a significant delay between onset of symptoms and diagnosis (mean 7.2 ± 3.5 months). All had sensorineural hearing loss, conforming to the JLNS phenotype. Mean QTc interval was 603 ± 93 ms, with T wave alternans (TWA) seen in all cases. All were started on propranolol and subsequently subjected to LCSD, and 3 underwent AAI permanent pacemaker implantation. Over a mean follow-up of 20 months, there was a significant reduction in QTc (603 ± 93 ms to 501 ± 33 ms, p = .04), which was persistent on follow-up (525 ± 41 ms) and only two out of six had persistent T wave alternans on ECG (p < .01). None of these children had presyncope, syncope, seizures, torsades de pointes, cardiac arrest or death on follow up following LCSD. CONCLUSION Jervell Lange-Nielsen syndrome is a subtype of LQTS with high-risk features. LCSD, an effective therapeutic option for those having symptoms despite being on propranolol, results in significant reduction of QTc interval and amelioration of symptoms.
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Affiliation(s)
- Deepanjan Bhattacharya
- Department of Cardiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | - Narayanan Namboodiri
- Department of Cardiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | | | - Mukund A Prabhu
- Department of Cardiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | | | - Sabarinath Menon
- Department of Cardiovascular and Thoracic Surgery, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | - Baiju S Dharan
- Department of Cardiovascular and Thoracic Surgery, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | - Ajitkumar Valaparambil
- Department of Cardiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
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23
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Milani G, Budriesi R, Tavazzani E, Cavalluzzi MM, Mattioli LB, Miniero DV, Delre P, Belviso BD, Denegri M, Cuocci C, Rotondo NP, De Palma A, Gualdani R, Caliandro R, Mangiatordi GF, Kumawat A, Camilloni C, Priori S, Lentini G. hERG stereoselective modulation by mexiletine-derived ureas: Molecular docking study, synthesis, and biological evaluation. Arch Pharm (Weinheim) 2023; 356:e2300116. [PMID: 37460390 DOI: 10.1002/ardp.202300116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 10/06/2023]
Abstract
Long QT syndrome (LQTS) is a disorder of cardiac electrophysiology resulting in life-threatening arrhythmias; nowadays, only a few drugs are available for the management of LQTS. Focusing our attention on LQT2, one of the most common subtypes of LQTS caused by mutations in the human ether-à-go-go-related gene (hERG), in the present work, the stereoselectivity of the recently discovered mexiletine-derived urea 8 was investigated on the hERG potassium channel. According to preliminary in silico predictions, in vitro studies revealed a stereoselective behavior, with the meso form showing the greatest hERG opening activity. In addition, functional studies on guinea pig isolated left atria, aorta, and ileum demonstrated that 8 does not present any cardiac or intestinal liability in our ex vivo studies. Due to its overall profile, (R,S)-8 paves the way for the design and development of a new series of compounds potentially useful in the treatment of both congenital and drug-induced forms of LQTS.
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Affiliation(s)
- Gualtiero Milani
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari Aldo Moro, Bari, Italy
| | - Roberta Budriesi
- Department of Pharmacy and Biotechnology, Food Chemistry and Nutraceutical Lab, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | | | | | - Laura Beatrice Mattioli
- Department of Pharmacy and Biotechnology, Food Chemistry and Nutraceutical Lab, Alma Mater Studiorum-University of Bologna, Bologna, Italy
| | - Daniela Valeria Miniero
- Department of Biosciences, Biotechnologies, and Environment, University Aldo Moro of Bari, Bari, Italy
| | - Pietro Delre
- Chemistry Department, University of Bari Aldo Moro, Bari, Italy
- CNR-Institute of Crystallography, Bari, Italy
| | | | | | | | - Natalie Paola Rotondo
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari Aldo Moro, Bari, Italy
| | - Annalisa De Palma
- Department of Biosciences, Biotechnologies, and Environment, University Aldo Moro of Bari, Bari, Italy
| | - Roberta Gualdani
- Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | | | | | - Amit Kumawat
- Department of Biosciences, University of Milan, Milano, Italy
| | - Carlo Camilloni
- Department of Biosciences, University of Milan, Milano, Italy
| | - Silvia Priori
- ICS-Maugeri IRCCS, Pavia, Italy
- Molecular Cardiology, Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain
| | - Giovanni Lentini
- Department of Pharmacy-Pharmaceutical Sciences, University of Bari Aldo Moro, Bari, Italy
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Ma JF, Zhou Y, Fu HX. Ventricular fibrillation induced by fever in structurally normal hearts. Front Cardiovasc Med 2023; 10:1230295. [PMID: 37817866 PMCID: PMC10561293 DOI: 10.3389/fcvm.2023.1230295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 08/25/2023] [Indexed: 10/12/2023] Open
Abstract
Ventricular fibrillation (VF) is a life-threatening arrhythmia that usually happens in patients with structural heart diseases. However, fever-induced ventricular fibrillation in structurally normal hearts was reported, and the four main diseases associated with these cases were Brugada syndrome, long QT syndrome, idiopathic ventricular fibrillation, and non-cardiovascular diseases. In this review, we analyzed this phenomenon and its clinical characteristics.
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Affiliation(s)
- Ji-Fang Ma
- Department of Cardiology, Fuwai Central China Cardiovascular Hospital, Zhengzhou, China
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25
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Klier K, Patel YJ, Schinköthe T, Harbeck N, Schmidt A. Corrected QT Interval (QTc) Diagnostic App for the Oncological Routine: Development Study. JMIR Cardio 2023; 7:e48096. [PMID: 37695655 PMCID: PMC10520775 DOI: 10.2196/48096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 06/20/2023] [Accepted: 06/21/2023] [Indexed: 09/12/2023] Open
Abstract
BACKGROUND Numerous antineoplastic drugs such as chemotherapeutics have cardiotoxic side effects and can lead to long QT syndrome (LQTS). When diagnosed and treated in time, the potentially fatal outcomes of LQTS can be prevented. Therefore, regular electrocardiogram (ECG) assessments are critical to ensure patient safety. However, these assessments are associated with patient discomfort and require timely support of the attending oncologist by a cardiologist. OBJECTIVE This study aimed to examine whether this approach can be made more efficient and comfortable by a smartphone app (QTc Tracker), supporting single-lead ECG records on site and transferring to a tele-cardiologist for an immediate diagnosis. METHODS To evaluate the QTc Tracker, it was implemented in 54 cancer centers in Germany. In total, 266 corrected QT interval (QTc) diagnoses of 122 patients were recorded. Moreover, a questionnaire on routine ECG workflow, turnaround time, and satisfaction (1=best, 6=worst) was answered by the centers before and after the implementation of the QTc Tracker. RESULTS Compared to the routine ECG workflow, the QTc Tracker enabled a substantial turnaround time reduction of 98% (mean 2.67, 95% CI 1.72-2.67 h) and even further time efficiency in combination with a cardiologic on-call service (mean 12.10, 95% CI 5.67-18.67 min). Additionally, nurses and patients reported higher satisfaction when using the QTc Tracker. In particular, patients' satisfaction sharply improved from 2.59 (95% CI 2.41-2.88) for the routine ECG workflow to 1.25 (95% CI 0.99-1.51) for the QTc Tracker workflow. CONCLUSIONS These results reveal a significant improvement regarding reduced turnaround time and increased user satisfaction. Best patient care might be guaranteed as the exposure of patients with an uncontrolled risk of QTc prolongations can be avoided by using the fast and easy QTc Tracker. In particular, as regular side-effect monitoring, the QTc Tracker app promises more convenience for patients and their physicians. Finally, future studies are needed to empirically test the usability and validity of such mobile ECG assessment methods. TRIAL REGISTRATION ClinicalTrials.gov NCT04055493; https://classic.clinicaltrials.gov/ct2/show/NCT04055493.
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Affiliation(s)
- Kristina Klier
- Institute of Sport Science, University of the Bundeswehr Munich, Neubiberg, Germany
| | | | - Timo Schinköthe
- CANKADO GmbH, Ottobrunn, Germany
- Research Center for Smart Digital Health, University of the Bundeswehr Munich, Neubiberg, Germany
| | - Nadia Harbeck
- Department of Gynecology and Obstetrics, Comprehensive Cancer Center of the Ludwig-Maximilians-University, Munich, Germany
| | - Annette Schmidt
- Institute of Sport Science, University of the Bundeswehr Munich, Neubiberg, Germany
- Research Center for Smart Digital Health, University of the Bundeswehr Munich, Neubiberg, Germany
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26
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Kass RS. Calmodulin mutations can underlie the phenotype of long QT syndrome variant 1. J Physiol 2023; 601:3695-3696. [PMID: 37555447 DOI: 10.1113/jp285220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023] Open
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27
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Zou X, Shanmugam SK, Kanner SA, Sampson KJ, Kass RS, Colecraft HM. Divergent regulation of KCNQ1/E1 by targeted recruitment of protein kinase A to distinct sites on the channel complex. eLife 2023; 12:e83466. [PMID: 37650513 PMCID: PMC10499372 DOI: 10.7554/elife.83466] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 08/30/2023] [Indexed: 09/01/2023] Open
Abstract
The slow delayed rectifier potassium current, IKs, conducted through pore-forming Q1 and auxiliary E1 ion channel complexes is important for human cardiac action potential repolarization. During exercise or fright, IKs is up-regulated by protein kinase A (PKA)-mediated Q1 phosphorylation to maintain heart rhythm and optimum cardiac performance. Sympathetic up-regulation of IKs requires recruitment of PKA holoenzyme (two regulatory - RI or RII - and two catalytic Cα subunits) to Q1 C-terminus by an A kinase anchoring protein (AKAP9). Mutations in Q1 or AKAP9 that abolish their functional interaction result in long QT syndrome type 1 and 11, respectively, which increases the risk of sudden cardiac death during exercise. Here, we investigated the utility of a targeted protein phosphorylation (TPP) approach to reconstitute PKA regulation of IKs in the absence of AKAP9. Targeted recruitment of endogenous Cα to E1-YFP using a GFP/YFP nanobody (nano) fused to RIIα enabled acute cAMP-mediated enhancement of IKs, reconstituting physiological regulation of the channel complex. By contrast, nano-mediated tethering of RIIα or Cα to Q1-YFP constitutively inhibited IKs by retaining the channel intracellularly in the endoplasmic reticulum and Golgi. Proteomic analysis revealed that distinct phosphorylation sites are modified by Cα targeted to Q1-YFP compared to free Cα. Thus, functional outcomes of synthetically recruited PKA on IKs regulation is critically dependent on the site of recruitment within the channel complex. The results reveal insights into divergent regulation of IKs by phosphorylation across different spatial and time scales, and suggest a TPP approach to develop new drugs to prevent exercise-induced sudden cardiac death.
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Affiliation(s)
- Xinle Zou
- Department of Molecular Pharmacology and Therapeutics, Columbia UniversityNew YorkUnited States
| | - Sri Karthika Shanmugam
- Department of Physiology and Cellular Biophysics, Columbia UniversityNew YorkUnited States
| | - Scott A Kanner
- Doctoral Program in Neurobiology and Behavior, Columbia UniversityNew YorkUnited States
| | - Kevin J Sampson
- Department of Molecular Pharmacology and Therapeutics, Columbia UniversityNew YorkUnited States
| | - Robert S Kass
- Department of Molecular Pharmacology and Therapeutics, Columbia UniversityNew YorkUnited States
| | - Henry M Colecraft
- Department of Molecular Pharmacology and Therapeutics, Columbia UniversityNew YorkUnited States
- Doctoral Program in Neurobiology and Behavior, Columbia UniversityNew YorkUnited States
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Baskar S, Czosek RJ, Spar DS. A Look Beyond the Sports Field: A Paradigm of Shared Decision Making in Everyday Life. J Am Coll Cardiol 2023; 82:612-614. [PMID: 37558374 DOI: 10.1016/j.jacc.2023.06.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 06/15/2023] [Indexed: 08/11/2023]
Affiliation(s)
- Shankar Baskar
- Cincinnati Children's Hospital Medical Center, The Heart Institute, Cincinnati, Ohio, USA.
| | - Richard J Czosek
- Cincinnati Children's Hospital Medical Center, The Heart Institute, Cincinnati, Ohio, USA
| | - David S Spar
- Cincinnati Children's Hospital Medical Center, The Heart Institute, Cincinnati, Ohio, USA
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Neves R, Bains S, Bos JM, MacIntyre CJ, Giudicessi JR, Ackerman MJ. Fatal Cardiac Arrhythmias During Electronic Gaming in Patients With Genetically Mediated Heart Diseases. J Am Coll Cardiol 2023; 82:603-611. [PMID: 37558373 DOI: 10.1016/j.jacc.2023.06.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 06/09/2023] [Accepted: 06/12/2023] [Indexed: 08/11/2023]
Abstract
BACKGROUND Recently, electronic gaming has been reported as a precipitant of life-threatening cardiac arrhythmias in susceptible individuals. However, the prevalence of cardiac events in genetic heart diseases (GHDs) in the setting of electronic gaming has not been established. OBJECTIVES In this study, we sought to define the prevalence of cardiac events occurring in the setting of electronic gaming in GHDs. METHODS Retrospective review of all patients evaluated and treated at Mayo Clinic's genetic heart rhythm clinic from July 2000 to November 2022 was performed to identify patients with a history of playing electronic games at the time of their cardiac event. Cardiac event was used to define events occurring before diagnosis, and breakthrough cardiac event (BCE) was used for events occurring after diagnosis. RESULTS Of the 3,370 patients with a GHD (mean age at first evaluation 27 ± 19 years, 55% female), 1,079 (32%) had a cardiac event before diagnosis, with 5 patients (0.5%) having an electronic gaming-associated event (3 catecholaminergic polymorphic ventricular tachycardia, 1 long QT syndrome, and 1 premature ventricular contraction-triggered ventricular fibrillation). After diagnosis and treatment, 431 patients (13%) experienced ≥1 BCE during follow-up, of which 1 electronic gaming-associated BCE (0.2%) occurred in a patient with catecholamine-sensitive right outflow tract ventricular tachycardia. CONCLUSIONS Although anecdotal cases of electronic gaming-associated life-threatening arrhythmias have been reported, in this largest single-center study to date, we show that these are extremely rare occurrences. While electronic gaming can have adverse health consequences, the threat of electronic gaming-triggered sudden death should not be used to try to curb time spent gaming.
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Affiliation(s)
- Raquel Neves
- Windland Smith Rice Sudden Death Genomics Laboratory, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA
| | - Sahej Bains
- Windland Smith Rice Sudden Death Genomics Laboratory, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA; Medical Scientist Training Program, Mayo Clinic Alix School of Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - J Martijn Bos
- Windland Smith Rice Sudden Death Genomics Laboratory, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA; Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Ciorsti J MacIntyre
- Windland Smith Rice Genetic Heart Rhythm Clinic, Division of Heart Rhythm Services, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - John R Giudicessi
- Windland Smith Rice Genetic Heart Rhythm Clinic, Division of Heart Rhythm Services, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Michael J Ackerman
- Windland Smith Rice Sudden Death Genomics Laboratory, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA; Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, USA; Windland Smith Rice Genetic Heart Rhythm Clinic, Division of Heart Rhythm Services, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA.
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30
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Cheng YW, Wu CT, Chang CJ, Yeh YH, Chang GJ, Tsai HY, Hsu LA. A Novel KCNH2 S981fs Mutation Identified by Whole-Exome Sequencing Is Associated with Type 2 Long QT Syndrome. Int J Mol Sci 2023; 24:12742. [PMID: 37628921 PMCID: PMC10454316 DOI: 10.3390/ijms241612742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/11/2023] [Accepted: 08/12/2023] [Indexed: 08/27/2023] Open
Abstract
KCNH2 loss-of-function mutations cause long QT syndrome type 2 (LQT2), an inherited cardiac disorder associated with life-threatening ventricular arrhythmia. Through whole-exome sequencing, we discovered a novel AGCGACAC deletion (S981fs) in the hERG gene of an LQT2 patient. Using a heterologous expression system and patch clamping, we found that the mutant K channel had reduced cell surface expression and lower current amplitude compared to the wild type. However, functional expression was restored by lowering temperature and using potassium channel inhibitors or openers (E4031, cisapride, nicorandil). Co-immunoprecipitation experiments confirmed the assembly of mutant proteins with wild-type hERG. Confocal imaging showed decreased hERG distribution on the cell membrane in cells expressing S981fs. Notably, treatment with G418 significantly increased hERG current in wild-type/S981fs heterozygotes. In conclusion, our study identifies a novel hERG mutation leading to impaired Kv11.1 function due to trafficking and nonsense-mediated RNA decay defects. These findings shed light on the mechanisms underlying LQT2 and offer potential therapeutic avenues.
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Affiliation(s)
- Yu-Wen Cheng
- Cardiovascular Division, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Tao-Yuan 33305, Taiwan; (Y.-W.C.); (C.-T.W.); (C.-J.C.); (Y.-H.Y.); (H.-Y.T.)
| | - Chia-Tung Wu
- Cardiovascular Division, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Tao-Yuan 33305, Taiwan; (Y.-W.C.); (C.-T.W.); (C.-J.C.); (Y.-H.Y.); (H.-Y.T.)
| | - Chi-Jen Chang
- Cardiovascular Division, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Tao-Yuan 33305, Taiwan; (Y.-W.C.); (C.-T.W.); (C.-J.C.); (Y.-H.Y.); (H.-Y.T.)
| | - Yung-Hsin Yeh
- Cardiovascular Division, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Tao-Yuan 33305, Taiwan; (Y.-W.C.); (C.-T.W.); (C.-J.C.); (Y.-H.Y.); (H.-Y.T.)
| | - Gwo-Jyh Chang
- Graduate Institute of Clinical Medical Sciences, Chang Gung University, Tao-Yuan 33305, Taiwan;
| | - Hsin-Yi Tsai
- Cardiovascular Division, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Tao-Yuan 33305, Taiwan; (Y.-W.C.); (C.-T.W.); (C.-J.C.); (Y.-H.Y.); (H.-Y.T.)
| | - Lung-An Hsu
- Cardiovascular Division, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Tao-Yuan 33305, Taiwan; (Y.-W.C.); (C.-T.W.); (C.-J.C.); (Y.-H.Y.); (H.-Y.T.)
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Kurzlechner LM, Kishnani S, Chowdhury S, Atkins SL, Moya-Mendez ME, Parker LE, Rosamilia MB, Tadros HJ, Pace LA, Patel V, Chahal CAA, Landstrom AP. DiscoVari: A Web-Based Precision Medicine Tool for Predicting Variant Pathogenicity in Cardiomyopathy- and Channelopathy-Associated Genes. Circ Genom Precis Med 2023; 16:317-327. [PMID: 37409478 PMCID: PMC10527712 DOI: 10.1161/circgen.122.003911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 05/30/2023] [Indexed: 07/07/2023]
Abstract
BACKGROUND With genetic testing advancements, the burden of incidentally identified cardiac disease-associated gene variants is rising. These variants may carry a risk of sudden cardiac death, highlighting the need for accurate diagnostic interpretation. We sought to identify pathogenic hotspots in sudden cardiac death-associated genes using amino acid-level signal-to-noise (S:N) analysis and develop a web-based precision medicine tool, DiscoVari, to improve variant evaluation. METHODS The minor allele frequency of putatively pathogenic variants was derived from cohort-based cardiomyopathy and channelopathy studies in the literature. We normalized disease-associated minor allele frequencies to rare variants in an ostensibly healthy population (Genome Aggregation Database) to calculate amino acid-level S:N. Amino acids with S:N above the gene-specific threshold were defined as hotspots. DiscoVari was built using JavaScript ES6 and using open-source JavaScript library ReactJS, web development framework Next.js, and JavaScript runtime NodeJS. We validated the ability of DiscoVari to identify pathogenic variants using variants from ClinVar and individuals clinically evaluated at the Duke University Hospitals with cardiac genetic testing. RESULTS We developed DiscoVari as an internet-based tool for S:N-based variant hotspots. Upon validation, a higher proportion of ClinVar likely pathogenic/pathogenic variants localized to DiscoVari hotspots (43.1%) than likely benign/benign variants (17.8%; P<0.0001). Further, 75.3% of ClinVar variants reclassified to likely pathogenic/pathogenic were in hotspots, compared with 41.3% of those reclassified as variants of uncertain significance (P<0.0001) and 23.4% of those reclassified as likely benign/benign (P<0.0001). Of the clinical cohort variants, 73.1% of likely pathogenic/pathogenic were in hotspots, compared with 0.0% of likely benign/benign (P<0.01). CONCLUSIONS DiscoVari reliably identifies disease-susceptible amino acid residues to evaluate variants by searching amino acid-specific S:N ratios.
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Affiliation(s)
| | - Sujata Kishnani
- Dept of Pediatrics, Division of Pediatric Cardiology, Durham, NC
| | - Shawon Chowdhury
- Dept of Pediatrics, Division of Pediatric Cardiology, Durham, NC
| | - Sage L. Atkins
- Dept of Pediatrics, Division of Pediatric Cardiology, Durham, NC
| | | | - Lauren E. Parker
- Dept of Pediatrics, Division of Pediatric Cardiology, Durham, NC
| | | | - Hanna J. Tadros
- Dept of Pediatrics, Section of Pediatric Cardiology, Baylor College of Medicine, Houston, TX
| | - Leslie A. Pace
- Dept of Pediatrics, Division of Pediatric Cardiology, Durham, NC
| | - Viraj Patel
- North West Thames Regional Genetics Service, St Mark’s Hospital, London, United Kingdom
| | - C. Anwar A. Chahal
- Center for Inherited Cardiovascular Diseases, WellSpan Health, Lancaster, PA
- Barts Heart Centre, St Bartholomew’s Hospital, Barts Health NHS Trust, London, United Kingdom
- Cardiac Electrophysiology, Cardiovascular Division, Hospital of the Univ of Pennsylvania, Philadelphia, PA
- Dept of Cardiovascular Medicine, Mayo Clinic, Rochester, MN
| | - Andrew P. Landstrom
- Dept of Pediatrics, Division of Pediatric Cardiology, Durham, NC
- Dept of Cell Biology, Duke Univ School of Medicine, Durham, NC
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De la Cruz A, Wu X, Rainer QC, Hiniesto-Iñigo I, Perez ME, Edler I, Liin SI, Larsson HP. Pharmacological Screening of Kv7.1 and Kv7.1/KCNE1 Activators as Potential Antiarrhythmic Drugs in the Zebrafish Heart. Int J Mol Sci 2023; 24:12092. [PMID: 37569465 PMCID: PMC10418701 DOI: 10.3390/ijms241512092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
Long QT syndrome (LQTS) can lead to ventricular arrhythmia and sudden cardiac death. The most common congenital cause of LQTS is mutations in the channel subunits generating the cardiac potassium current IKs. Zebrafish (Danio rerio) have been proposed as a powerful system to model human cardiac diseases due to the similar electrical properties of the zebrafish heart and the human heart. We used high-resolution all-optical electrophysiology on ex vivo zebrafish hearts to assess the effects of IKs analogues on the cardiac action potential. We found that chromanol 293B (an IKs inhibitor) prolonged the action potential duration (APD) in the presence of E4031 (an IKr inhibitor applied to drug-induced LQT2), and to a lesser extent, in the absence of E4031. Moreover, we showed that PUFA analogues slightly shortened the APD of the zebrafish heart. However, PUFA analogues failed to reverse the APD prolongation in drug-induced LQT2. However, a more potent IKs activator, ML-277, partially reversed the APD prolongation in drug-induced LQT2 zebrafish hearts. Our results suggest that IKs plays a limited role in ventricular repolarizations in the zebrafish heart under resting conditions, although it plays a more important role when the IKr is compromised, as if the IKs in zebrafish serves as a repolarization reserve as in human hearts. This study shows that potent IKs activators can restore the action potential duration in drug-induced LQT2 in the zebrafish heart.
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Affiliation(s)
- Alicia De la Cruz
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, 1600 NW 10th Avenue, Miami, FL 33136, USA
| | - Xiaoan Wu
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, 1600 NW 10th Avenue, Miami, FL 33136, USA
| | - Quinn C. Rainer
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, 1600 NW 10th Avenue, Miami, FL 33136, USA
| | - Irene Hiniesto-Iñigo
- Department of Biomedical and Clinical Sciences, Linköping University, SE-581 85 Linköping, Sweden
| | - Marta E. Perez
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, 1600 NW 10th Avenue, Miami, FL 33136, USA
| | - Isak Edler
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, 1600 NW 10th Avenue, Miami, FL 33136, USA
- Department of Biomedical and Clinical Sciences, Linköping University, SE-581 85 Linköping, Sweden
| | - Sara I. Liin
- Department of Biomedical and Clinical Sciences, Linköping University, SE-581 85 Linköping, Sweden
| | - H. Peter Larsson
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, 1600 NW 10th Avenue, Miami, FL 33136, USA
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Patterson DR, Pan JA, Hosadurg N, Morsy M. Sudden Cardiac Arrest in the Postpartum Period Due to Long QT Syndrome and Dilated Cardiomyopathy. JACC Case Rep 2023; 16:101882. [PMID: 37396328 PMCID: PMC10313482 DOI: 10.1016/j.jaccas.2023.101882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 04/10/2023] [Accepted: 04/20/2023] [Indexed: 07/04/2023]
Abstract
We describe the case of a previously healthy patient presenting with sudden cardiac arrest in the postpartum period as a result of concomitant congenital type 1 long QT syndrome and BAG3 dilated cardiomyopathy. This case highlights the increased rate of cardiac events for patients with long QT syndrome in the postpartum period. (Level of Difficulty: Advanced.).
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Affiliation(s)
| | | | | | - Mohamed Morsy
- University of Virginia, Charlottesville, Virginia, USA
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Fazelifar AF, Pourirahim M, Masoumi T, Biglari A, Maleki M, Kalayinia S. Identification of a novel pathogenic variant in KCNH2 in an Iranian family with long QT syndrome 2 by whole-exome sequencing. J Arrhythm 2023; 39:430-453. [PMID: 37324772 PMCID: PMC10264754 DOI: 10.1002/joa3.12857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 04/05/2023] [Accepted: 04/06/2023] [Indexed: 06/17/2023] Open
Abstract
Background Long QT syndrome (LQTS) is a lethal cardiac condition. However, the clinical implementation of genetic testing has now made LQTS eminently treatable. Next-generation sequencing has remarkable potential for both clinical diagnostics and research of LQTS. Here, we investigated the genetic etiology in an LQTS-suspected Iranian pedigree by whole-exome sequencing and collected all KCNH2 variants with consensus based on publications. Methods WES was performed on the proband of this pedigree to reveal the underlying cause of sudden cardiac death (SCD). The variant found was validated and segregated by polymerase chain reaction and Sanger sequencing. Based on the literature review, KCNH2 variants were retrospectively analyzed to identify pathogenic variants, likely pathogenic variants, and variants of uncertain significance by using different prediction tools. Results WES identified an autosomal dominant nonsense variant, c.1425C>A: p.Tyr475Ter, in the KCNH2 gene, which appeared to be the most likely cause of LQTS in this pedigree. Moreover, our comprehensive literature review yielded 511 KCNH2 variants in association with the LQTS phenotype, with c.3002G>A (CADD Phred=49) being the most pathogenic variant. Conclusions Variants in the KCNH2 gene are considered a major cause of LQTS worldwide. The detected c.1425C>A is a novel variant to be reported from Iran for the first time. This result indicates the importance of KCNH2 screening in a pedigree with SCD cases.
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Affiliation(s)
- Amir Farjam Fazelifar
- Rajaie Cardiovascular Medical and Research CenterIran University of Medical SciencesTehranIran
| | - Maryam Pourirahim
- Cardiogenetic Research Center, Rajaie Cardiovascular Medical and Research CenterIran University of Medical SciencesTehranIran
| | - Tannaz Masoumi
- Rajaie Cardiovascular Medical and Research CenterIran University of Medical SciencesTehranIran
| | - Alireza Biglari
- Department of Genetics & Molecular Medicine, School of MedicineZanjan University of Medical SciencesZanjanIran
| | - Majid Maleki
- Cardiogenetic Research Center, Rajaie Cardiovascular Medical and Research CenterIran University of Medical SciencesTehranIran
| | - Samira Kalayinia
- Cardiogenetic Research Center, Rajaie Cardiovascular Medical and Research CenterIran University of Medical SciencesTehranIran
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Moore OM, Ho KS, Copeland JS, Parthasarathy V, Wehrens XHT. Genome Editing and Cardiac Arrhythmias. Cells 2023; 12:1363. [PMID: 37408197 DOI: 10.3390/cells12101363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/05/2023] [Accepted: 05/09/2023] [Indexed: 07/07/2023] Open
Abstract
This article reviews progress in the field of cardiac genome editing, in particular, its potential utility in treating cardiac arrhythmias. First, we discuss genome editing methods by which DNA can be disrupted, inserted, deleted, or corrected in cardiomyocytes. Second, we provide an overview of in vivo genome editing in preclinical models of heritable and acquired arrhythmias. Third, we discuss recent advancements in cardiac gene transfer, including delivery methods, gene expression optimization, and potential adverse effects associated with therapeutic somatic genome editing. While genome editing for cardiac arrhythmias is still in its infancy, this approach holds great promise, especially for inherited arrhythmia syndromes with a defined genetic defect.
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Affiliation(s)
- Oliver M Moore
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Integrative Physiology, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Kevin S Ho
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Integrative Physiology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Juwan S Copeland
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Vaidya Parthasarathy
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Integrative Physiology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Xander H T Wehrens
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Integrative Physiology, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
- Center for Space Medicine, Baylor College of Medicine, Houston, TX 77030, USA
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Robyns T, Nuyens D, Vandenberk B, Haemers P, Breckpot J, Garweg C, Ector J, Willems R. Individualized QT interval (QTi) is a powerful diagnostic tool in long QT syndrome: results from a large validation study. Front Cardiovasc Med 2023; 10:1097468. [PMID: 37252121 PMCID: PMC10213876 DOI: 10.3389/fcvm.2023.1097468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 04/25/2023] [Indexed: 05/31/2023] Open
Abstract
Aims Diagnosis of Long QT syndrome (LQTS) is based on prolongation of the QT interval corrected for heart rate (QTc) on surface ECG and genotyping. However, up to 25% of genotype positive patients have a normal QTc interval. We recently showed that individualized QT interval (QTi) derived from 24 h holter data and defined as the QT value at the intersection of an RR interval of 1,000 ms with the linear regression line fitted through QT-RR data points of each individual patient was superior over QTc to predict mutation status in LQTS families. This study aimed to confirm the diagnostic value of QTi, fine-tune its cut-off value and evaluate intra-individual variability in patients with LQTS. Methods From the Telemetric and Holter ECG Warehouse, 201 recordings from control individuals and 393 recordings from 254 LQTS patients were analysed. Cut-off values were obtained from ROC curves and validated against an in house LQTS and control cohort. Results ROC curves indicated very good discrimination between controls and LQTS patients with QTi, both in females (AUC 0.96) and males (AUC 0.97). Using a gender dependent cut-off of 445 ms in females and 430 ms in males, a sensitivity of 88% and specificity of 96% were achieved, which was confirmed in the validation cohort. No significant intra-individual variability in QTi was observed in 76 LQTS patients for whom at least two holter recordings were available (483 ± 36 ms vs. 489 ± 42 ms, p = 0.11). Conclusions This study confirms our initial findings and supports the use of QTi in the evaluation of LQTS families. Using the novel gender dependent cut-off values, a high diagnostic accuracy was achieved.
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Affiliation(s)
- Tomas Robyns
- Department of Cardiovascular Diseases, University Hospitals Leuven, Leuven, Belgium
- Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Dieter Nuyens
- Department of Cardiology, Ziekenhuis Oost Limburg Genk, Genk, Belgium
| | - Bert Vandenberk
- Department of Cardiovascular Diseases, University Hospitals Leuven, Leuven, Belgium
- Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Peter Haemers
- Department of Cardiovascular Diseases, University Hospitals Leuven, Leuven, Belgium
- Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Jeroen Breckpot
- Department of Human Genetics, University Hospitals Leuven, Leuven, Belgium
| | - Christophe Garweg
- Department of Cardiovascular Diseases, University Hospitals Leuven, Leuven, Belgium
- Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Joris Ector
- Department of Cardiovascular Diseases, University Hospitals Leuven, Leuven, Belgium
- Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Rik Willems
- Department of Cardiovascular Diseases, University Hospitals Leuven, Leuven, Belgium
- Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
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Clemens DJ, Ye D, Wang L, Kim CSJ, Zhou W, Dotzler SM, Tester DJ, Marty I, Knollmann BC, Ackerman MJ. Cellular and electrophysiological characterization of triadin knockout syndrome using induced pluripotent stem cell-derived cardiomyocytes. Stem Cell Reports 2023; 18:1075-1089. [PMID: 37163978 PMCID: PMC10202692 DOI: 10.1016/j.stemcr.2023.04.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 04/07/2023] [Accepted: 04/11/2023] [Indexed: 05/12/2023] Open
Abstract
Triadin knockout syndrome (TKOS) is a malignant arrhythmia disorder caused by recessive null variants in TRDN-encoded cardiac triadin. Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) were generated from two unrelated TKOS patients and an unrelated control. CRISPR-Cas9 gene editing was used to insert homozygous TRDN-p.D18fs∗13 into a control line to generate a TKOS model (TRDN-/-). Western blot confirmed total knockout of triadin in patient-specific and TRDN-/- iPSC-CMs. iPSC-CMs from both patients revealed a prolonged action potential duration (APD) at 90% repolarization, and this was normalized by protein replacement of triadin. APD prolongation was confirmed in TRDN-/- iPSC-CMs. TRDN-/- iPSC-CMs revealed that loss of triadin underlies decreased expression and co-localization of key calcium handling proteins, slow and decreased calcium release from the sarcoplasmic reticulum, and slow inactivation of the L-type calcium channel leading to frequent cellular arrhythmias, including early and delayed afterdepolarizations and APD alternans.
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Affiliation(s)
- Daniel J Clemens
- Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA
| | - Dan Ye
- Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Mayo Clinic, Rochester, MN, USA
| | - Lili Wang
- Department of Medicine, Vanderbilt Center for Arrhythmia Research and Therapeutics, Nashville, TN, USA
| | - C S John Kim
- Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Mayo Clinic, Rochester, MN, USA
| | - Wei Zhou
- Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Mayo Clinic, Rochester, MN, USA
| | - Steven M Dotzler
- Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA
| | - David J Tester
- Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Mayo Clinic, Rochester, MN, USA
| | - Isabelle Marty
- University Grenoble Alpes, INSERM U1216, CHU Grenoble Alpes, Grenoble Institute Neurosciences, 38000 Grenoble, France
| | - Bjorn C Knollmann
- Department of Medicine, Vanderbilt Center for Arrhythmia Research and Therapeutics, Nashville, TN, USA; Vanderbilt School of Medicine, Nashville, TN, USA
| | - Michael J Ackerman
- Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Mayo Clinic, Rochester, MN, USA; Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, MN, USA.
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Muhammad A, Calandranis ME, Li B, Yang T, Blackwell DJ, Harvey ML, Smith JE, Chew AE, Capra JA, Matreyek KA, Fowler DM, Roden DM, Glazer AM. High-throughput functional mapping of variants in an arrhythmia gene, KCNE1, reveals novel biology. bioRxiv 2023:2023.04.28.538612. [PMID: 37162834 PMCID: PMC10168370 DOI: 10.1101/2023.04.28.538612] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Background KCNE1 encodes a 129-residue cardiac potassium channel (IKs) subunit. KCNE1 variants are associated with long QT syndrome and atrial fibrillation. However, most variants have insufficient evidence of clinical consequences and thus limited clinical utility. Results Here, we demonstrate the power of variant effect mapping, which couples saturation mutagenesis with high-throughput sequencing, to ascertain the function of thousands of protein coding KCNE1 variants. We comprehensively assayed KCNE1 variant cell surface expression (2,554/2,709 possible single amino acid variants) and function (2,539 variants). We identified 470 loss-of-surface expression and 588 loss-of-function variants. Out of the 588 loss-of-function variants, only 155 had low cell surface expression. The latter half of the protein is dispensable for protein trafficking but essential for channel function. 22 of the 30 KCNE1 residues (73%) highly intolerant of variation were in predicted close contact with binding partners KCNQ1 or calmodulin. Our data were highly concordant with gold standard electrophysiological data (ρ = -0.65), population and patient cohorts (32/38 concordant variants), and computational metrics (ρ = -0.55). Our data provide moderate-strength evidence for the ACMG/AMP functional criteria for benign and pathogenic variants. Conclusions Comprehensive variant effect maps of KCNE1 can both provide insight into IKs channel biology and help reclassify variants of uncertain significance.
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Affiliation(s)
- Ayesha Muhammad
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Medical Scientist Training Program, Vanderbilt University, Nashville, TN 37232, USA
| | - Maria E. Calandranis
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Bian Li
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Tao Yang
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Daniel J. Blackwell
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - M. Lorena Harvey
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jeremy E. Smith
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Ashli E. Chew
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - John A. Capra
- Bakar Computational Health Sciences Institute and Department of Epidemiology and Biostatistics, University of California, San Francisco, CA 94143, USA
| | - Kenneth A. Matreyek
- Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Douglas M. Fowler
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Dan M. Roden
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Andrew M. Glazer
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN 37232, USA
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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Maeda T, Yoshizawa K, Watanabe K, Mori O, Toyota N. Defibrillator electrode placement in the pleural cavity for a child. Asian Cardiovasc Thorac Ann 2023:2184923231171998. [PMID: 37093739 DOI: 10.1177/02184923231171998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Implantable cardioverter defibrillators are implanted in children to prevent sudden death due to life-threatening ventricular arrhythmias. Transvenous electrode placement is difficult for children because of the small vessel size. Especially, defibrillator electrode placement requires other innovative techniques. We successfully implanted a defibrillator electrode in the pleural cavity using a thoracoscopic approach for a 4-year-old child with sodium channelopathy.
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Affiliation(s)
- Toshi Maeda
- Department of Cardiovascular Surgery, Hyogo Prefectural Amagasaki General Medical Center, Hyogo, Japan
| | - Kosuke Yoshizawa
- Department of Cardiovascular Surgery, Hyogo Prefectural Amagasaki General Medical Center, Hyogo, Japan
| | - Kentaro Watanabe
- Department of Pediatric Surgery, Hyogo Prefectural Amagasaki General Medical Center, Hyogo, Japan
| | - Otohime Mori
- Department of Cardiovascular Surgery, Hyogo Prefectural Amagasaki General Medical Center, Hyogo, Japan
| | - Naoki Toyota
- Department of Pediatric Cardiology, Hyogo Prefectural Amagasaki General Medical Center, Hyogo, Japan
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Maines E, Moretti M, Vitturi N, Gugelmo G, Fasan I, Lenzini L, Piccoli G, Gragnaniello V, Maiorana A, Soffiati M, Burlina A, Franceschi R. Understanding the Pathogenesis of Cardiac Complications in Patients with Propionic Acidemia and Exploring Therapeutic Alternatives for Those Who Are Not Eligible or Are Waiting for Liver Transplantation. Metabolites 2023; 13:563. [PMID: 37110221 PMCID: PMC10143878 DOI: 10.3390/metabo13040563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
The guidelines for the management of patients affected by propionic acidemia (PA) recommend standard cardiac therapy in the presence of cardiac complications. A recent revision questioned the impact of high doses of coenzyme Q10 on cardiac function in patients with cardiomyopathy (CM). Liver transplantation is a therapeutic option for several patients since it may stabilize or reverse CM. Both the patients waiting for liver transplantation and, even more, the ones not eligible for transplant programs urgently need therapies to improve cardiac function. To this aim, the identification of the pathogenetic mechanisms represents a key point. Aims: This review summarizes: (1) the current knowledge of the pathogenetic mechanisms underlying cardiac complications in PA and (2) the available and potential pharmacological options for the prevention or the treatment of cardiac complications in PA. To select articles, we searched the electronic database PubMed using the Mesh terms "propionic acidemia" OR "propionate" AND "cardiomyopathy" OR "Long QT syndrome". We selected 77 studies, enlightening 12 potential disease-specific or non-disease-specific pathogenetic mechanisms, namely: impaired substrate delivery to TCA cycle and TCA dysfunction, secondary mitochondrial electron transport chain dysfunction and oxidative stress, coenzyme Q10 deficiency, metabolic reprogramming, carnitine deficiency, cardiac excitation-contraction coupling alteration, genetics, epigenetics, microRNAs, micronutrients deficiencies, renin-angiotensin-aldosterone system activation, and increased sympathetic activation. We provide a critical discussion of the related therapeutic options. Current literature supports the involvement of multiple cellular pathways in cardiac complications of PA, indicating the growing complexity of their pathophysiology. Elucidating the mechanisms responsible for such abnormalities is essential to identify therapeutic strategies going beyond the correction of the enzymatic defect rather than engaging the dysregulated mechanisms. Although these approaches are not expected to be resolutive, they may improve the quality of life and slow the disease progression. Available pharmacological options are limited and tested in small cohorts. Indeed, a multicenter approach is mandatory to strengthen the efficacy of therapeutic options.
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Affiliation(s)
- Evelina Maines
- Division of Pediatrics, Santa Chiara General Hospital, APSS, 38122 Trento, Italy
| | - Michele Moretti
- Division of Cardiology, Santa Chiara General Hospital, APSS, 38122 Trento, Italy
| | - Nicola Vitturi
- Division of Metabolic Diseases, Department of Medicine-DIMED, University Hospital, 35128 Padova, Italy
| | - Giorgia Gugelmo
- Division of Clinical Nutrition, Department of Medicine-DIMED, University Hospital, 35128 Padova, Italy
| | - Ilaria Fasan
- Division of Clinical Nutrition, Department of Medicine-DIMED, University Hospital, 35128 Padova, Italy
| | - Livia Lenzini
- Emergency Medicine Unit, Department of Medicine-DIMED, University Hospital, 35128 Padova, Italy
| | - Giovanni Piccoli
- CIBIO, Department of Cellular, Computational and Integrative Biology, Italy & Dulbecco Telethon Institute, Università degli Studi di Trento, 38123 Trento, Italy
| | - Vincenza Gragnaniello
- Division of Inherited Metabolic Diseases, Reference Centre Expanded Newborn Screening, Department of Women’s and Children’s Health, University Hospital, 35128 Padova, Italy
| | - Arianna Maiorana
- Division of Metabolism and Research Unit of Metabolic Biochemistry, Bambino Gesù Children’s Hospital-IRCCS, 00165 Rome, Italy
| | - Massimo Soffiati
- Division of Pediatrics, Santa Chiara General Hospital, APSS, 38122 Trento, Italy
| | - Alberto Burlina
- Division of Inherited Metabolic Diseases, Reference Centre Expanded Newborn Screening, Department of Women’s and Children’s Health, University Hospital, 35128 Padova, Italy
| | - Roberto Franceschi
- Division of Pediatrics, Santa Chiara General Hospital, APSS, 38122 Trento, Italy
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Delinière A, Haddad C, Herrera-Siklody C, Hermida A, Pruvot E, Bressieux-Degueldre S, Millat G, Janin A, Hermida JS, Asatryan B, Chevalier P. Phenotypic Characterization of Timothy Syndrome Caused by the CACNA1C p.Gly402Ser Variant. Circ Genom Precis Med 2023:e004010. [PMID: 37009738 DOI: 10.1161/circgen.122.004010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
Affiliation(s)
- Antoine Delinière
- National Reference Center for Inherited Arrhythmias of Lyon, Department of Cardiac Electrophysiology, Hôpital Cardiologique Louis Pradel, Hospices Civils de Lyon (HCL), Bron (A.D., C.H., P.C.)
- University of Lyon, Claude Bernard Lyon 1 University, MeLiS, CNRS UMR 5284, INSERM U1314, Institut NeuroMyoGène, Lyon, France (A.D., P.C.)
| | - Christelle Haddad
- National Reference Center for Inherited Arrhythmias of Lyon, Department of Cardiac Electrophysiology, Hôpital Cardiologique Louis Pradel, Hospices Civils de Lyon (HCL), Bron (A.D., C.H., P.C.)
| | - Claudia Herrera-Siklody
- Arrhythmia Unit, Department of Cardiology, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland (C.H.-S., P.C.)
| | - Alexis Hermida
- Cardiology, Arrhythmia, and Cardiac Stimulation Service, Amiens-Picardie University Hospital, Amiens, France (A.H., J.-S.H.)
| | | | - Sabrina Bressieux-Degueldre
- Pediatric Cardiology Unit, Woman-Mother-Child Department, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland (S.B.-D.)
| | - Gilles Millat
- Cardiogenetic laboratory, Centre de biologie et pathologie Est, Hospices Civils de Lyon (HCL), Lyon, France (G.M., A.J.)
| | - Alexandre Janin
- Cardiogenetic laboratory, Centre de biologie et pathologie Est, Hospices Civils de Lyon (HCL), Lyon, France (G.M., A.J.)
| | - Jean-Sylvain Hermida
- Cardiology, Arrhythmia, and Cardiac Stimulation Service, Amiens-Picardie University Hospital, Amiens, France (A.H., J.-S.H.)
| | - Babken Asatryan
- Department of Cardiology, Inselspital, Bern University Hospital, Switzerland (B.A.)
| | - Philippe Chevalier
- National Reference Center for Inherited Arrhythmias of Lyon, Department of Cardiac Electrophysiology, Hôpital Cardiologique Louis Pradel, Hospices Civils de Lyon (HCL), Bron (A.D., C.H., P.C.)
- University of Lyon, Claude Bernard Lyon 1 University, MeLiS, CNRS UMR 5284, INSERM U1314, Institut NeuroMyoGène, Lyon, France (A.D., P.C.)
- Arrhythmia Unit, Department of Cardiology, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland (C.H.-S., P.C.)
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Pegu B, Singh R. Anesthetic management of a young primigravida a case of symptomatic long QT syndrome with a permanent pacemaker in-situ undergoing lower segment cesarean section delivery: A case report. Saudi J Anaesth 2023; 17:256-259. [PMID: 37260636 PMCID: PMC10228844 DOI: 10.4103/sja.sja_688_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 09/25/2022] [Indexed: 06/02/2023] Open
Abstract
The patient with Long QT syndrome (LQTS) presents a unique challenge to the anesthesiologist. The anesthetic management of such patients requires a good knowledge of the pathophysiology of this rare disease. General anesthesia (GA) or combined spinal epidural anesthesia (CSEA) are the most preferred anesthetic techniques among anesthesiologists for such patients posted for the lower segment cesarean section delivery. In this report, we would like to share our experience of anesthetic management of a young primigravida, a case of symptomatic LQTS with a permanent pacemaker in situ. Anesthetic technique used for the lower segment cesarean section delivery was single-shot spinal anesthesia using a combination of a local anesthetic and strong opioid in the lumber subarachnoid space. Until recently, only one report in the literature has described this single-shot spinal technique for such cases. The advantages of single shot spinal over GA and CSEA can be utilized in a select group of these patients, which include fast onset, dense, reliable block with low local anesthetic toxicity, reduced catecholamine release, and relatively prolonged analgesia when combined with an opioid.
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Affiliation(s)
- Baby Pegu
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Ram Singh
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
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Shao H, Shi D, Dai Y. Linezolid and the risk of QT interval prolongation: A pharmacovigilance study of the Food and Drug Administration Adverse Event Reporting System. Br J Clin Pharmacol 2023; 89:1386-1392. [PMID: 36346345 DOI: 10.1111/bcp.15587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 10/26/2022] [Accepted: 10/31/2022] [Indexed: 11/09/2022] Open
Abstract
AIMS Few studies have investigated linezolid (LZD)-associated cardiotoxicity. This study explored the potential association between LZD and QT interval prolongation. METHODS Adverse event reports of QT interval prolongation associated with LZD from the Food and Drug Administration Adverse Event Reporting System from January 2013 to December 2021 were analysed and the reporting odds ratio (ROR) with 95% confidence intervals were calculated. RESULTS A total of 6738 adverse event reports of LZD as the primary and secondary suspected drug were obtained from the database, including 192 reports with electrocardiogram QT prolonged (QTp), and the ROR value was 26.1 (95% CI = 22.6-30.2). There were 8 reports of long QT syndrome, ROR 14.2 (95% CI = 7.1-28.5); 5 reports of torsade de pointes, ROR 3.2 (95% CI = 1.3-7.6); and 5 reports of ventricular tachycardia, ROR 1.9 (95% CI = 0.8-4.5). Subgroup analysis revealed that patients with tuberculosis treated with LZD had a higher reporting rate among all QTp reports, exhibiting an odds ratio of 330.0 (95% CI = 223.1-488.1). The odds ratios of QTp associated with LZD treatments in patients with and without tuberculosis were 4.2 (95% CI = 3.4-5.3) and 1.2 (95% CI = 0.8-1.6), respectively. CONCLUSION The study showed an association between LZD and QT interval prolongation. In the report on patients with tuberculosis, the incidence of QTp was higher when treated with LZD.
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Affiliation(s)
- Haixia Shao
- Department of Pharmacy, Second Affiliated Hospital and Yuying Children's hospital of Wenzhou Medical University, Wenzhou City, China
| | - Dawei Shi
- Department of Pharmacy, First Affiliated Hospital of Wenzhou Medical University, Wenzhou City, China
| | - Ying Dai
- Department of Pharmacy, First Affiliated Hospital of Wenzhou Medical University, Wenzhou City, China
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Alameh M, Oliveira-Mendes BR, Kyndt F, Rivron J, Denjoy I, Lesage F, Schott JJ, De Waard M, Loussouarn G. A need for exhaustive and standardized characterization of ion channels activity. The case of K V11.1. Front Physiol 2023; 14:1132533. [PMID: 36860515 PMCID: PMC9968853 DOI: 10.3389/fphys.2023.1132533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 01/30/2023] [Indexed: 02/16/2023] Open
Abstract
hERG, the pore-forming subunit of the rapid component of the delayed rectifier K+ current, plays a key role in ventricular repolarization. Mutations in the KCNH2 gene encoding hERG are associated with several cardiac rhythmic disorders, mainly the Long QT syndrome (LQTS) characterized by prolonged ventricular repolarization, leading to ventricular tachyarrhythmias, sometimes progressing to ventricular fibrillation and sudden death. Over the past few years, the emergence of next-generation sequencing has revealed an increasing number of genetic variants including KCNH2 variants. However, the potential pathogenicity of the majority of the variants remains unknown, thus classifying them as variants of uncertain significance or VUS. With diseases such as LQTS being associated with sudden death, identifying patients at risk by determining the variant pathogenicity, is crucial. The purpose of this review is to describe, on the basis of an exhaustive examination of the 1322 missense variants, the nature of the functional assays undertaken so far and their limitations. A detailed analysis of 38 hERG missense variants identified in Long QT French patients and studied in electrophysiology also underlies the incomplete characterization of the biophysical properties for each variant. These analyses lead to two conclusions: first, the function of many hERG variants has never been looked at and, second, the functional studies done so far are excessively heterogeneous regarding the stimulation protocols, cellular models, experimental temperatures, homozygous and/or the heterozygous condition under study, a context that may lead to conflicting conclusions. The state of the literature emphasizes how necessary and important it is to perform an exhaustive functional characterization of hERG variants and to standardize this effort for meaningful comparison among variants. The review ends with suggestions to create a unique homogeneous protocol that could be shared and adopted among scientists and that would facilitate cardiologists and geneticists in patient counseling and management.
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Affiliation(s)
- Malak Alameh
- CNRS, INSERM, l’institut du thorax, Nantes Université, CHU Nantes, Nantes, France,Labex ICST, INSERM, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d’Azur, Valbonne, France
| | - Barbara Ribeiro Oliveira-Mendes
- CNRS, INSERM, l’institut du thorax, Nantes Université, CHU Nantes, Nantes, France,*Correspondence: Barbara Ribeiro Oliveira-Mendes,
| | - Florence Kyndt
- CNRS, INSERM, l’institut du thorax, Nantes Université, CHU Nantes, Nantes, France
| | - Jordan Rivron
- CNRS, INSERM, l’institut du thorax, Nantes Université, CHU Nantes, Nantes, France
| | - Isabelle Denjoy
- Service de Cardiologie et CNMR Maladies Cardiaques Héréditaires Rares, Hôpital Bichat, Paris, France
| | - Florian Lesage
- Labex ICST, INSERM, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d’Azur, Valbonne, France
| | - Jean-Jacques Schott
- CNRS, INSERM, l’institut du thorax, Nantes Université, CHU Nantes, Nantes, France
| | - Michel De Waard
- CNRS, INSERM, l’institut du thorax, Nantes Université, CHU Nantes, Nantes, France,Labex ICST, INSERM, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d’Azur, Valbonne, France
| | - Gildas Loussouarn
- CNRS, INSERM, l’institut du thorax, Nantes Université, CHU Nantes, Nantes, France
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Bains S, Neves R, Bos JM, Giudicessi JR, MacIntyre C, Ackerman MJ. Phenotypes of Overdiagnosed Long QT Syndrome. J Am Coll Cardiol 2023; 81:477-86. [PMID: 36725176 DOI: 10.1016/j.jacc.2022.11.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/18/2022] [Accepted: 11/03/2022] [Indexed: 02/01/2023]
Abstract
BACKGROUND Long QT syndrome (LQTS) predisposes individuals to arrhythmic syncope or seizure, sudden cardiac arrest, or sudden cardiac death (SCD). Increased physician and public awareness of LQTS-associated warning signs and an increase in electrocardiographic screening programs may contribute to overdiagnosis of LQTS. OBJECTIVES This study sought to identify the diagnostic miscues underlying the continued overdiagnosis of LQTS. METHODS Electronic medical records were reviewed for patients who arrived with an outside diagnosis of LQTS but were dismissed as having normal findings subsequently. Data were abstracted for details on referral, clinical history, and both cardiologic and genetic test results. RESULTS Overall, 290 of 1,841 (16%) patients with original diagnosis of LQTS (174 [60%] female; mean age at first Mayo Clinic evaluation, 22 ± 14 years; mean QTc interval, 427 ± 25 milliseconds) were dismissed as having normal findings. The main cause of LQTS misdiagnosis or overdiagnosis was a prolonged QTc interval secondary to vasovagal syncope (n = 87; 30%), followed by a seemingly positive genetic test result for a variant in 1 of the main LQTS genes (n = 68; 23%) that was ultimately deemed not to be of clinical significance. Furthermore, patients received misdiagnoses because of a positive family history of SCD that was deemed unrelated to LQTS (n = 46; 16%), isolated/transient QT prolongation (n = 44; 15%), or misinterpretation of the QTc interval as a result of inclusion of the U-wave (n = 40, 14%). CONCLUSIONS Knowing the 5 main determinants of discordance between a previously rendered diagnosis of LQTS and full diagnostic reversal or removal (vasovagal syncope, "pseudo"-positive genetic test result in LQTS-causative genes, family history of SCD, transient QT prolongation, and misinterpretation of the QTc interval) increases awareness and provides critical guidance to reduce this burden of overdiagnosed LQTS.
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Wilde AAM, Schwartz PJ. Long QT Syndrome, a Diagnosis That Warrants Expert Opinion and Expert Centers. J Am Coll Cardiol 2023; 81:487-9. [PMID: 36725177 DOI: 10.1016/j.jacc.2022.11.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 02/01/2023]
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Assaf A, Theuns DA, Michels M, Roos-Hesselink J, Szili-Torok T, Yap SC. Usefulness of insertable cardiac monitors for risk stratification: current indications and clinical evidence. Expert Rev Med Devices 2023; 20:85-97. [PMID: 36695092 DOI: 10.1080/17434440.2023.2171862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
INTRODUCTION The 2018 ESC Syncope guidelines expanded the indications for an insertable cardiac monitor (ICM) to patients with unexplained syncope and primary cardiomyopathy or inheritable arrhythmogenic disorders. AREAS COVERED This review article discusses the clinical evidence for using an ICM for risk stratification in different patient populations including Brugada syndrome, long QT syndrome, hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, cardiac sarcoidosis, and congenital heart disease. EXPERT OPINION Clinical data on the usefulness of ICMs in different patient populations is limited but most studies demonstrate early detection of clinically relevant arrhythmias, such as nonsustained ventricular tachycardia or atrial fibrillation. It is important to emphasize that the study populations usually comprise selected populations where conventional diagnostic methods fail to clarify the mechanism of symptoms. The effect of an ICM on prognosis by earlier detection of arrhythmias is difficult to demonstrate in populations with rare disease. Risk stratification in patients with cardiomyopathy or inheritable arrhythmogenic disorders remains a niche indication for ICMs. The most important indication for an ICM remains unexplained syncope in patients at low risk of SCD. Given the device costs and uncertain clinical value of device-detected arrhythmias, it is unclear whether it is also useful in non-syncopal patients.
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Affiliation(s)
- Amira Assaf
- Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Dominic Amj Theuns
- Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Michelle Michels
- Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Jolien Roos-Hesselink
- Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Tamas Szili-Torok
- Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Sing-Chien Yap
- Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands
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Souilla L, Avesani M, Boisson A, Requirand A, Matecki S, Vincenti M, Werner O, De La Villeon G, Pommier V, Pasquie JL, Guillaumont S, Amedro P. Cardiorespiratory fitness, muscle fitness, and physical activity in children with long QT syndrome: A prospective controlled study. Front Cardiovasc Med 2023; 9:1081106. [PMID: 36712265 PMCID: PMC9874118 DOI: 10.3389/fcvm.2022.1081106] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/28/2022] [Indexed: 01/13/2023] Open
Abstract
Background In children with congenital long QT syndrome (LQTS), the risk of arrhythmic events during exercise commonly makes it difficult to balance exercise restrictions versus promotion of physical activity. Nevertheless, in children with LQTS, cardiorespiratory fitness, muscle fitness, and physical activity, have been scarcely explored. Materials and methods In this prospective, controlled, cross-sectional study, 20 children with LQTS (12.7 ± 3.7 years old) and 20 healthy controls (11.9 ± 2.4 years old) were enrolled. All participants underwent a cardiopulmonary exercise test, a muscular architecture ultrasound assessment, (cross-sectional area on right rectus femoris and pennation angle), a handgrip muscular strength evaluation, and a standing long broad jump test. The level of physical activity was determined using with a waist-worn tri-axial accelerometer (Actigraph GT3X). Results Peak oxygen uptake (VO2peak) and ventilatory anaerobic threshold (VAT) were lower in children with LQTS than in healthy controls (33.9 ± 6.2 mL/Kg/min vs. 40.1 ± 6.6 mL/Kg/min, P = 0.010; 23.8 ± 5.1 mL/Kg/min vs. 28.8 ± 5.5 mL/Kg/min, P = 0.007, respectively). Children with LQTS had lower standing long broad jump distance (119.5 ± 33.2 cm vs. 147.3 ± 36.1 cm, P = 0.02) and pennation angle (12.2 ± 2.4° vs. 14.3 ± 2.8°, P = 0.02). No differences in terms of moderate-to-vigorous physical activity were observed (36.9 ± 12.9 min/day vs. 41.5 ± 18.7 min/day, P = 0.66), but nearly all children were below the WHO guidelines. Conclusion Despite similar physical activity level, cardiorespiratory fitness and muscle fitness in children with LQTS were lower than in healthy controls. The origin of this limitation seemed to be multifactorial, involving beta-blocker induced chronotropic limitation, physical and muscle deconditioning. Cardiovascular rehabilitation could be of interest in children with LQTS with significant physical limitation.
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Affiliation(s)
- Luc Souilla
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France,PhyMedExp, Univ Montpellier, INSERM, French National Centre for Scientific Research (CNRS), Montpellier, France
| | - Martina Avesani
- Department of Paediatric and Adult Congenital Cardiology, M3C National Reference Centre, Bordeaux University Hospital, Pessac, France
| | - Aymeric Boisson
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France
| | - Anne Requirand
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France,Department of Physiology, University Hospital of Montpellier, Montpellier, France
| | - Stefan Matecki
- PhyMedExp, Univ Montpellier, INSERM, French National Centre for Scientific Research (CNRS), Montpellier, France,Department of Physiology, University Hospital of Montpellier, Montpellier, France
| | - Marie Vincenti
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France,PhyMedExp, Univ Montpellier, INSERM, French National Centre for Scientific Research (CNRS), Montpellier, France
| | - Oscar Werner
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France,Paediatric Cardiology and Rehabilitation Unit, Saint-Pierre Institute, Palavas-Les-Flots, France
| | - Gregoire De La Villeon
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France,Paediatric Cardiology and Rehabilitation Unit, Saint-Pierre Institute, Palavas-Les-Flots, France
| | - Victor Pommier
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France,Paediatric Cardiology and Rehabilitation Unit, Saint-Pierre Institute, Palavas-Les-Flots, France
| | - Jean-Luc Pasquie
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France,PhyMedExp, Univ Montpellier, INSERM, French National Centre for Scientific Research (CNRS), Montpellier, France
| | - Sophie Guillaumont
- Department of Paediatric and Congenital Cardiology, M3C Regional Reference Centre, University Hospital, Montpellier, France,Paediatric Cardiology and Rehabilitation Unit, Saint-Pierre Institute, Palavas-Les-Flots, France
| | - Pascal Amedro
- Department of Paediatric and Adult Congenital Cardiology, M3C National Reference Centre, Bordeaux University Hospital, Pessac, France,Inserm, U1045, Institut Hospitalo-Universitaire (IHU) Liryc, Bordeaux Cardio-Thoracic Research Centre, Electrophysiology and Heart Modelling Institute, University of Bordeaux, Pessac, France,*Correspondence: Pascal Amedro,
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Abstract
Cardiac alternans arises from dynamical instabilities in the electrical and calcium cycling systems of the heart, and often precedes ventricular arrhythmias and sudden cardiac death. In this review, we integrate clinical observations with theory and experiment to paint a holistic portrait of cardiac alternans: the underlying mechanisms, arrhythmic manifestations and electrocardiographic signatures. We first summarize the cellular and tissue mechanisms of alternans that have been demonstrated both theoretically and experimentally, including 3 voltage-driven and 2 calcium-driven alternans mechanisms. Based on experimental and simulation results, we describe their relevance to mechanisms of arrhythmogenesis under different disease conditions, and their link to electrocardiographic characteristics of alternans observed in patients. Our major conclusion is that alternans is not only a predictor, but also a causal mechanism of potentially lethal ventricular and atrial arrhythmias across the full spectrum of arrhythmia mechanisms that culminate in functional reentry, although less important for anatomic reentry and focal arrhythmias.
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Affiliation(s)
- Zhilin Qu
- Departments of Medicine (Cardiology), Physiology, and Computational Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA
| | - James N. Weiss
- Departments of Medicine (Cardiology), Physiology, and Computational Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA
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50
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Asatryan B, Barth AS. Sex-related differences in incidence, phenotype and risk of sudden cardiac death in inherited arrhythmia syndromes. Front Cardiovasc Med 2023; 9:1010748. [PMID: 36684594 PMCID: PMC9845907 DOI: 10.3389/fcvm.2022.1010748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 12/08/2022] [Indexed: 01/06/2023] Open
Abstract
Inherited Arrhythmia Syndromes (IAS) including long QT and Brugada Syndrome, are characterized by life-threatening arrhythmias in the absence of apparent structural heart disease and are caused by pathogenic variants in genes encoding cardiac ion channels or associated proteins. Studies of large pedigrees of families affected by IAS have demonstrated incomplete penetrance and variable expressivity. Biological sex is one of several factors that have been recognized to modulate disease severity in IAS. There is a growing body of evidence linking sex hormones to the susceptibility to arrhythmias, yet, many sex-specific disease aspects remain underrecognized as female sex and women with IAS are underinvestigated and findings from male-predominant cohorts are often generalized to both sexes with minimal to no consideration of relevant sex-associated differences in prevalence, disease manifestations and outcome. In this review, we highlight current knowledge of sex-related biological differences in normal cardiac electrophysiology and sex-associated factors that influence IAS phenotypes.
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Affiliation(s)
- Babken Asatryan
- Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Andreas S. Barth
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States,*Correspondence: Andreas S. Barth ✉
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