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de Alencar JN, de Andrade Matos VF, Scheffer MK, Felicioni SP, De Marchi MFN, Martínez-Sellés M. ST segment and T wave abnormalities: A narrative review. J Electrocardiol 2024; 85:7-15. [PMID: 38810594 DOI: 10.1016/j.jelectrocard.2024.05.085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 05/12/2024] [Accepted: 05/14/2024] [Indexed: 05/31/2024]
Abstract
INTRODUCTION The electrocardiogram (ECG) is a valuable tool for interpreting ventricular repolarization. This article aims to broaden the diagnostic scope beyond the conventional ischemia-centric approach, integrating an understanding of pathophisiological influences on ST-T wave changes. METHODS A review was conducted on the physiological underpinnings of ventricular repolarization and the pathophisiological processes that can change ECG patterns. The research encompassed primary repolarization abnormalities due to uniform variations in ventricular action potential, secondary changes from electrical or mechanical alterations, and non-ischemic conditions influencing ST-T segments. RESULTS Primary T waves are characterized by symmetrical waves with broad bases and variable QT intervals, indicative of direct myocardial action potential modifications due to ischemia, electrolyte imbalances, and channelopathies. Secondary T waves are asymmetric and often unassociated with significant QT interval changes, suggesting depolarization alterations or changes in cardiac geometry and contractility. CONCLUSION We advocate for a unified ECG analysis, recognizing primary and secondary ST-T changes, and their clinical implications. Our proposed analytical framework enhances the clinician's ability to discern a wide array of cardiac conditions, extending diagnostic accuracy beyond myocardial ischemia.
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Affiliation(s)
| | | | | | | | | | - Manuel Martínez-Sellés
- Cardiology Department, Hospital General Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Madrid, Spain; Universidad Europea, Universidad Complutense, Madrid, Spain
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Del Duca F, Ghamlouch A, Manetti AC, Napoletano G, Sonnini E, Treves B, De Matteis A, La Russa R, Sheppard MN, Fineschi V, Maiese A. Sudden Cardiac Death, Post-Mortem Investigation: A Proposing Panel of First Line and Second Line Genetic Tests. J Pers Med 2024; 14:544. [PMID: 38793126 PMCID: PMC11122432 DOI: 10.3390/jpm14050544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/02/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024] Open
Abstract
Investigating the causes of Sudden cardiac death (SCD) is always difficult; in fact, genetic cardiac conditions associated with SCD could be "silent" even during autopsy investigation. In these cases, it is important to exclude other aetiology and assist to ask for genetic investigations. Herein, the purpose of this review is to collect the most-implicated genes in SCD and generate a panel with indications for first line and second line investigations. A systematic review of genetic disorders that may cause SCD in the general population was carried out according to the Preferred Reporting Item for Systematic Review (PRISMA) standards. We subsequently listed the genes that may be tested in the case of sudden cardiac death when the autopsy results are negative or with no evidence of acquired cardiac conditions. To make genetic tests more specific and efficient, it is useful and demanded to corroborate autopsy findings with the molecular investigation as evident in the panel proposed. The genes for first line investigations are HCM, MYBPC3, MYH7, TNNT2, TNNI3, while in case of DCM, the most implicated genes are LMNA and TTN, and in second line for these CDM, ACTN2, TPM1, C1QPB could be investigated. In cases of ACM/ARVC, the molecular investigation includes DSP, DSG2, DSC2, RYR2, PKP2. The channelopathies are associated with the following genes: SCN5A, KCNQ1, KCNH2, KCNE1, RYR2. Our work underlines the importance of genetic tests in forensic medicine and clinical pathology; moreover, it could be helpful not only to assist the pathologists to reach a diagnosis, but also to prevent other cases of SCD in the family of the descendant and to standardise the type of analysis performed in similar cases worldwide.
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Affiliation(s)
- Fabio Del Duca
- Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Rome, Viale Regina Elena 336, 00161 Rome, Italy; (F.D.D.); (A.G.); (G.N.); (B.T.); (A.D.M.); (V.F.)
| | - Alessandro Ghamlouch
- Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Rome, Viale Regina Elena 336, 00161 Rome, Italy; (F.D.D.); (A.G.); (G.N.); (B.T.); (A.D.M.); (V.F.)
| | - Alice Chiara Manetti
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, 00168 Rome, Italy;
| | - Gabriele Napoletano
- Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Rome, Viale Regina Elena 336, 00161 Rome, Italy; (F.D.D.); (A.G.); (G.N.); (B.T.); (A.D.M.); (V.F.)
| | - Elena Sonnini
- Medicina Genomica, Dipartimento Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, 00168 Rome, Italy;
| | - Biancamaria Treves
- Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Rome, Viale Regina Elena 336, 00161 Rome, Italy; (F.D.D.); (A.G.); (G.N.); (B.T.); (A.D.M.); (V.F.)
| | - Alessandra De Matteis
- Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Rome, Viale Regina Elena 336, 00161 Rome, Italy; (F.D.D.); (A.G.); (G.N.); (B.T.); (A.D.M.); (V.F.)
| | - Raffaele La Russa
- Department of Clinical Medicine, Public Health, Life Sciences, and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy
| | - Mary N. Sheppard
- Department of Cardiovascular Pathology, Level 1, Jenner Wing Corridor 4, St George’s University of London, Cranmer Terrace, London SW17 0RE, UK;
| | - Vittorio Fineschi
- Department of Anatomical, Histological, Forensic and Orthopedic Sciences, Sapienza University of Rome, Viale Regina Elena 336, 00161 Rome, Italy; (F.D.D.); (A.G.); (G.N.); (B.T.); (A.D.M.); (V.F.)
| | - Aniello Maiese
- Department of Surgical Pathology, Medical, Molecular and Critical Area, Institute of Legal Medicine, University of Pisa, 56126 Pisa, Italy
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Balestra E, Bobbo M, Cittar M, Chicco D, D’Agata Mottolese B, Barbi E, Caiffa T. Congenital Long QT Syndrome in Children and Adolescents: A General Overview. CHILDREN (BASEL, SWITZERLAND) 2024; 11:582. [PMID: 38790576 PMCID: PMC11119491 DOI: 10.3390/children11050582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 04/24/2024] [Accepted: 05/06/2024] [Indexed: 05/26/2024]
Abstract
Congenital long QT syndrome (LQTS) represents a disorder of myocardial repolarization characterized by a prolongation of QTc interval on ECG, which can degenerate into fast polymorphic ventricular arrhythmias. The typical symptoms of LQTS are syncope and palpitations, mainly triggered by adrenergic stimuli, but it can also manifest with cardiac arrest. At least 17 genotypes have been associated with LQTS, with a specific genotype-phenotype relationship described for the three most common subtypes (LQTS1, -2, and -3). β-Blockers are the first-line therapy for LQTS, even if the choice of the appropriate patients needing to be treated may be challenging. In specific cases, interventional measures, such as an implantable cardioverter-defibrillator (ICD) or left cardiac sympathetic denervation (LCSD), are useful. The aim of this review is to highlight the current state-of-the-art knowledge on LQTS, providing an updated picture of possible diagnostic algorithms and therapeutic management.
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Affiliation(s)
- Elia Balestra
- Department of Medical, Surgical and Health Sciences, University of Trieste, 34127 Trieste, Italy;
| | - Marco Bobbo
- Institute for Maternal and Child Health, IRCCS “Burlo Garofolo”, 34127 Trieste, Italy; (M.B.); (D.C.); (B.D.M.); (T.C.)
| | - Marco Cittar
- Cardiovascular Department, Centre for Diagnosis and Management of Cardiomyopathies, Azienda Sanitaria Universitaria Integrata di Trieste, University of Trieste, 34127 Trieste, Italy;
| | - Daniela Chicco
- Institute for Maternal and Child Health, IRCCS “Burlo Garofolo”, 34127 Trieste, Italy; (M.B.); (D.C.); (B.D.M.); (T.C.)
| | - Biancamaria D’Agata Mottolese
- Institute for Maternal and Child Health, IRCCS “Burlo Garofolo”, 34127 Trieste, Italy; (M.B.); (D.C.); (B.D.M.); (T.C.)
| | - Egidio Barbi
- Department of Medical, Surgical and Health Sciences, University of Trieste, 34127 Trieste, Italy;
- Institute for Maternal and Child Health, IRCCS “Burlo Garofolo”, 34127 Trieste, Italy; (M.B.); (D.C.); (B.D.M.); (T.C.)
| | - Thomas Caiffa
- Institute for Maternal and Child Health, IRCCS “Burlo Garofolo”, 34127 Trieste, Italy; (M.B.); (D.C.); (B.D.M.); (T.C.)
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Rebolledo‐Del Toro M, Carvajalino‐Galeano AB, Pinto‐Brito C, Muñoz‐Velandia OM, García‐Peña ÁA. Use of portable single-lead electrocardiogram device as an alternative for QTc monitoring in critically ill patients. Ann Noninvasive Electrocardiol 2024; 29:e13116. [PMID: 38627955 PMCID: PMC11021801 DOI: 10.1111/anec.13116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/13/2024] [Accepted: 03/24/2024] [Indexed: 04/19/2024] Open
Abstract
PURPOSE Acquired QT prolongation is frequent and leads to a higher mortality rate in critically ill patients. KardiaMobile 1L® (KM1L) is a portable, user-friendly single lead, mobile alternative to conventional 12-lead electrocardiogram (12-L ECG) that could be more readily available, potentially facilitating more frequent QTc assessments in intensive care units (ICU); however, there is currently no evidence to validate this potential use. METHODS We conducted a prospective diagnostic test study comparing QT interval measurement using KM1L with conventional 12-L ECG ordered for any reason in patients admitted to an ICU. We compared the mean difference using a paired t-test, agreement using Bland-Altman analysis, and Lin's concordance coefficient, numerical precision (proportion of QT measurements with <10 ms difference between KM1L and conventional 12-L ECG), and clinical precision (concordance for adequate discrimination of prolonged QTc). RESULTS We included 114 patients (61.4% men, 60% cardiovascular etiology of hospitalization) with 131 12-L ECG traces. We found no statistical difference between corrected QT measurements (427 ms vs. 428 ms, p = .308). Lin's concordance coefficient was 0.848 (95% CI 0.801-0.894, p = .001). Clinical precision was excellent in males and substantial in females (Kappa 0.837 and 0.781, respectively). Numerical precision was lower in patients with vasoactive drugs (-13.99 ms), QT-prolonging drugs (13.84 ms), antiarrhythmic drugs (-12.87 ms), and a heart rate (HR) difference of ≥5 beats per minute (bpm) between devices (-11.26 ms). CONCLUSION Our study validates the clinical viability of KM1L, a single-lead mobile ECG device, for identifying prolonged QT intervals in ICU patients. Caution is warranted in patients with certain medical conditions that may affect numerical precision.
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Affiliation(s)
- Martin Rebolledo‐Del Toro
- Division of CardiologyHospital Universitario San IgnacioBogotaColombia
- Department of Internal MedicinePontificia Universidad JaverianaBogotaColombia
| | | | | | - Oscar Mauricio Muñoz‐Velandia
- Department of Internal MedicinePontificia Universidad JaverianaBogotaColombia
- Department of Internal MedicineHospital Universitario San IgnacioBogotaColombia
| | - Ángel Alberto García‐Peña
- Division of CardiologyHospital Universitario San IgnacioBogotaColombia
- Department of Internal MedicinePontificia Universidad JaverianaBogotaColombia
- Department of Internal MedicineHospital Universitario San IgnacioBogotaColombia
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Hu J, Song Y, Huang X, Li C, Jin X, Cen L, Zhang C, Ding B, Lian J. Opioids-Induced Long QT Syndrome: A Challenge to Cardiac Health. Cardiovasc Toxicol 2024; 24:472-480. [PMID: 38630336 PMCID: PMC11076354 DOI: 10.1007/s12012-024-09853-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 03/28/2024] [Indexed: 05/08/2024]
Abstract
The challenge posed by opioid overdose has become a significant concern for health systems due to the complexities associated with drug prohibition, widespread clinical use, and potential abuse. In response, healthcare professionals have primarily concentrated on mitigating the hallucinogenic and respiratory depressant consequences of opioid overdose to minimize associated risks. However, it is crucial to acknowledge that most opioids possess the capacity to prolong the QT interval, particularly in cases of overdose, thereby potentially resulting in severe ventricular arrhythmias and even sudden death if timely intervention is not implemented. Consequently, alongside addressing the typical adverse effects of opioids, it is imperative to consider their cardiotoxicity. To enhance comprehension of the correlation between opioids and arrhythmias, identify potential targets for prompt intervention, and mitigate the hazards associated with clinical utilization, an exploration of the interaction between drugs and ion channels, as well as their underlying mechanisms, becomes indispensable. This review primarily concentrates on elucidating the impact of opioid drugs on diverse ion channels, investigating recent advancements in this domain, and attaining a deeper understanding of the mechanisms underlying the prolongation of the QT interval by opioid drugs, along with potential interventions.
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Affiliation(s)
- Jiale Hu
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China
| | - Yongfei Song
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China
- Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo Medical Center Lihuili Hospital, Ningbo University, No. 378 Dongqing Road, Yinzhou District, Ningbo, 315000, Zhejiang, China
| | - Xiaoyan Huang
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China
- Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo Medical Center Lihuili Hospital, Ningbo University, No. 378 Dongqing Road, Yinzhou District, Ningbo, 315000, Zhejiang, China
| | - Chongrong Li
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China
| | - Xiaojun Jin
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China
| | - Lichao Cen
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China
| | - Chuanjin Zhang
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China
| | - Beilei Ding
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China
| | - Jiangfang Lian
- Department of Cardiology, Ningbo University Health Science Center Affiliated Lihuili Hospital, Ningbo University, Zhejiang, China.
- Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo Medical Center Lihuili Hospital, Ningbo University, No. 378 Dongqing Road, Yinzhou District, Ningbo, 315000, Zhejiang, China.
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Zhao Z, Zang X, Niu K, Song W, Wang X, Mügge A, Aweimer A, Hamdani N, Zhou X, Zhao Y, Akin I, El-Battrawy I. Impacts of gene variants on drug effects-the foundation of genotype-guided pharmacologic therapy for long QT syndrome and short QT syndrome. EBioMedicine 2024; 103:105108. [PMID: 38653189 PMCID: PMC11041837 DOI: 10.1016/j.ebiom.2024.105108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 03/20/2024] [Accepted: 03/24/2024] [Indexed: 04/25/2024] Open
Abstract
The clinical significance of optimal pharmacotherapy for inherited arrhythmias such as short QT syndrome (SQTS) and long QT syndrome (LQTS) has been increasingly recognised. The advancement of gene technology has opened up new possibilities for identifying genetic variations and investigating the pathophysiological roles and mechanisms of genetic arrhythmias. Numerous variants in various genes have been proven to be causative in genetic arrhythmias. Studies have demonstrated that the effectiveness of certain drugs is specific to the patient or genotype, indicating the important role of gene-variants in drug response. This review aims to summarize the reported data on the impact of different gene-variants on drug response in SQTS and LQTS, as well as discuss the potential mechanisms by which gene-variants alter drug response. These findings may provide valuable information for future studies on the influence of gene variants on drug efficacy and the development of genotype-guided or precision treatment for these diseases.
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Affiliation(s)
- Zhihan Zhao
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China
| | - Xiaobiao Zang
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China
| | - Kerun Niu
- Department of Orthopaedic, Henan Provincial People's Hospital; Zhengzhou University People's Hospital, Zhengzhou, Henan, 450003, China
| | - Weifeng Song
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China
| | - Xianqing Wang
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China
| | - Andreas Mügge
- Department of Cardiology and Angiology, Bergmannsheil University Hospitals, Ruhr University of Bochum, 44789, Bochum, Germany
| | - Assem Aweimer
- Institute of Physiology, Department of Cellular and Translational Physiology, Medical Faculty and Institut für Forschung und Lehre (IFL), Molecular and Experimental Cardiology, Ruhr University Bochum, Bochum, Germany
| | - Nazha Hamdani
- Institute of Physiology, Department of Cellular and Translational Physiology, Medical Faculty and Institut für Forschung und Lehre (IFL), Molecular and Experimental Cardiology, Ruhr University Bochum, Bochum, Germany
- HCEMM-Cardiovascular Research Group, Department of Pharmacology and Pharmacotherapy, University of Budapest, Budapest, Hungary
- Department of Physiology, Cardiovascular Research Institute Maastricht University Maastricht, Maastricht, the Netherlands
| | - Xiaobo Zhou
- Cardiology, Angiology, Haemostaseology, and Medical Intensive Care, Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
- German Center for Cardiovascular Research (DZHK) Partner Site Heidelberg/Mannheim, Medical Centre Mannheim, Heidelberg University, Germany
- 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, Sichuan, China
| | - Yonghui Zhao
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, Henan, 450003, China
| | - Ibrahim Akin
- Cardiology, Angiology, Haemostaseology, and Medical Intensive Care, Medical Centre Mannheim, Medical Faculty Mannheim, Heidelberg University, Germany
- German Center for Cardiovascular Research (DZHK) Partner Site Heidelberg/Mannheim, Medical Centre Mannheim, Heidelberg University, Germany
| | - Ibrahim El-Battrawy
- Department of Cardiology and Angiology, Bergmannsheil University Hospitals, Ruhr University of Bochum, 44789, Bochum, Germany
- Institute of Physiology, Department of Cellular and Translational Physiology, Medical Faculty and Institut für Forschung und Lehre (IFL), Molecular and Experimental Cardiology, Ruhr University Bochum, Bochum, Germany
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Mehta A, Chandiramani R, Ghosh B, Asatryan B, Hajra A, Barth AS. Catheter Ablation for Channelopathies: When Is Less More? J Clin Med 2024; 13:2384. [PMID: 38673656 PMCID: PMC11051330 DOI: 10.3390/jcm13082384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/05/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
Ventricular fibrillation (VF) is a common cause of sudden cardiac death in patients with channelopathies, particularly in the young population. Although pharmacological treatment, cardiac sympathectomy, and implantable cardioverter defibrillators (ICD) have been the mainstay in the management of VF in patients with channelopathies, they are associated with significant adverse effects and complications, leading to poor quality of life. Given these drawbacks, catheter ablation has been proposed as a therapeutic option for patients with channelopathies. Advances in imaging techniques and modern mapping technologies have enabled increased precision in identifying arrhythmia triggers and substrate modification. This has aided our understanding of the underlying pathophysiology of ventricular arrhythmias in channelopathies, highlighting the roles of the Purkinje network and the epicardial right ventricular outflow tract in arrhythmogenesis. This review explores the role of catheter ablation in managing the most common channelopathies (Brugada syndrome, congenital long QT syndrome, short QT syndrome, and catecholaminergic polymorphic ventricular tachycardia). While the initial results for ablation in Brugada syndrome are promising, the long-term efficacy and durability of ablation in different channelopathies require further investigation. Given the genetic and phenotypic heterogeneity of channelopathies, future studies are needed to show whether catheter ablation in patients with channelopathies is associated with a reduction in VF, and psychological distress stemming from recurrent ICD shocks, particularly relative to other available therapeutic options (e.g., quinidine in high-risk Brugada patients).
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Affiliation(s)
- Adhya Mehta
- Department of Internal Medicine, Albert Einstein College of Medicine/Jacobi Medical Center, Bronx, NY 10461, USA
| | - Rishi Chandiramani
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Binita Ghosh
- Department of Internal Medicine, SSM Health St. Mary Hospital, St. Louis, MO 63117, USA;
| | - Babken Asatryan
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Adrija Hajra
- Department of Internal Medicine, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Andreas S. Barth
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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8
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Lee SY, Lee BK. Palpitations and Recurrent Syncope in a Young Woman. Circulation 2024; 149:402-405. [PMID: 38285741 DOI: 10.1161/circulationaha.123.067865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Accepted: 12/11/2023] [Indexed: 01/31/2024]
Affiliation(s)
- Sun Yong Lee
- Department of Internal Medicine, San Joaquin General Hospital, French Camp, CA (S.Y.L.)
| | - Byron K Lee
- Division of Cardiology, University of California, San Francisco (B.K.L.)
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9
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Casoria V, Greet V, Auckburally A, Murphy S, Flaherty D. Comparison of the effects of propofol and alfaxalone on the electrocardiogram of dogs, with particular reference to QT interval. Front Vet Sci 2024; 10:1330111. [PMID: 38260194 PMCID: PMC10800659 DOI: 10.3389/fvets.2023.1330111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 12/18/2023] [Indexed: 01/24/2024] Open
Abstract
Cardiac electrical activity is often altered by administration of anesthetic drugs. While the effects of propofol in this regard have previously been described in dogs, to date, there are no reports of the effect of alfaxalone. This study investigated the impact of both propofol and alfaxalone on the ECG of 60 dogs, after premedication with acepromazine and methadone. Heart rate increased significantly in both groups. The PR and QRS intervals were significantly increased following propofol while with alfaxalone the QRS duration was significantly increased and ST segment depression was observed. The QT and JT interval were significantly shorter following induction with alfaxalone, but, when corrected (c) for heart rate, QTc and JTc in both groups were significantly greater following induction. When comparing the magnitude of change between groups, the change in RR interval was greater in the alfaxalone group. The change in both QT and JT intervals were significantly greater following alfaxalone, but when QTc and JTc intervals were compared, there were no significant differences between the two drugs. The similarly increased QTc produced by both drugs may suggest comparable proarrhythmic effects.
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Affiliation(s)
- Vincenzo Casoria
- Department of Anaesthesia and Analgesia, Southern Counties Veterinary Specialists, Ringwood, United Kingdom
| | - Victoria Greet
- Department of Cardiology, Southern Counties Veterinary Specialists, Ringwood, United Kingdom
| | - Adam Auckburally
- Department of Anaesthesia and Analgesia, Southern Counties Veterinary Specialists, Ringwood, United Kingdom
| | - Steve Murphy
- Department of Anaesthesia and Analgesia, Southern Counties Veterinary Specialists, Ringwood, United Kingdom
| | - Derek Flaherty
- Department of Anaesthesia and Analgesia, Southern Counties Veterinary Specialists, Ringwood, United Kingdom
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10
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Yun KM, Narezkina A, Redfern C, Velasco K, Bazhenova L. Repotrectinib in a Patient With NTRK Fusion-Positive Pancreatic Carcinoma and Congenital Long QT Syndrome. JCO Precis Oncol 2024; 8:e2300265. [PMID: 38271657 PMCID: PMC10830087 DOI: 10.1200/po.23.00265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 11/02/2023] [Accepted: 11/04/2023] [Indexed: 01/27/2024] Open
Abstract
Repotrectinib in a patient with NTRK fusion-positive pancreatic carcinoma and congenital long QT syndrome.
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Affiliation(s)
- Karen M. Yun
- Division of Hematology-Oncology, Moores Cancer Center at UC San Diego Health, La Jolla, CA
| | - Anna Narezkina
- Division of Cardiology, University of California Medical Center and Sulpizio Cardiovascular Center, La Jolla, CA
| | | | - Katherine Velasco
- Division of Hematology-Oncology, Moores Cancer Center at UC San Diego Health, La Jolla, CA
| | - Lyudmila Bazhenova
- Division of Hematology-Oncology, Moores Cancer Center at UC San Diego Health, La Jolla, CA
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11
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Postema PG. Editorial commentary: Precision therapy in congenital Long QT syndrome: The future is today. Trends Cardiovasc Med 2024; 34:48-49. [PMID: 35788048 DOI: 10.1016/j.tcm.2022.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 06/26/2022] [Indexed: 11/25/2022]
Affiliation(s)
- Pieter G Postema
- Heart Center, Department of Clinical and Experimental Cardiology, Amsterdam UMC, University of Amsterdam, Cardiovascular Sciences, Meibergdreef 9, Amsterdam, the Netherlands.
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Sadlonova M, Beach SR, Funk MC, Rosen JH, Ramirez Gamero AF, Karlson RA, Huffman JC, Celano CM. Risk Stratification of QTc Prolongation in Critically Ill Patients Receiving Antipsychotics for the Management of Delirium Symptoms. J Intensive Care Med 2023:8850666231222470. [PMID: 38130132 DOI: 10.1177/08850666231222470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
BACKGROUND Patients experiencing significant agitation or perceptual disturbances related to delirium in an intensive care setting may benefit from short-term treatment with an antipsychotic medication. Some antipsychotic medications may prolong the QTc interval, which increases the risk of potentially fatal ventricular arrhythmias. In this targeted review, we describe the evidence regarding the relationships between antipsychotic medications and QTc prolongation and practical methods for monitoring the QTc interval and mitigating arrhythmia risk. METHODS Searches of PubMed and Cochrane Library were performed to identify studies, published before February 2023, investigating the relationships between antipsychotic medications and QTc prolongation or arrhythmias. RESULTS Most antipsychotic medications commonly used for the management of delirium symptoms (eg, intravenous haloperidol, olanzapine, quetiapine) cause a moderate degree of QTc prolongation. Among other antipsychotics, those most likely to cause QTc prolongation are iloperidone and ziprasidone, while aripiprazole and lurasidone appear to have minimal risk for QTc prolongation. Genetic vulnerabilities, female sex, older age, pre-existing cardiovascular disease, electrolyte abnormalities, and non-psychiatric medications also increase the risk of QTc prolongation. For individuals at risk of QTc prolongation, it is essential to measure the QTc interval accurately and consistently and consider medication adjustments if needed. CONCLUSIONS Antipsychotic medications are one of many risk factors for QTc prolongation. When managing agitation related to delirium, it is imperative to assess an individual patient's risk for QTc prolongation and to choose a medication and monitoring strategy commensurate to the risks. In intensive care settings, we recommend regular ECG monitoring, using a linear regression formula to correct for heart rate. If substantial QTc prolongation (eg, QTc > 500 msec) is present, a change in pharmacologic treatment can be considered, though a particular medication may still be warranted if the risks of discontinuation (eg, extreme agitation, removal of invasive monitoring devices) outweigh the risks of arrhythmias. AIMS This review aims to summarize the current literature on relationships between antipsychotic medications and QTc prolongation and to make practical clinical recommendations towards the approach of antipsychotic medication use for the management of delirium-related agitation and perceptual disturbances in intensive care settings.
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Affiliation(s)
- Monika Sadlonova
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
- Department of Psychosomatic Medicine and Psychotherapy, University of Göttingen Medical Center, Göttingen, Germany
- Department of Cardiovascular and Thoracic Surgery, University of Göttingen Medical Center, Göttingen, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Göttingen, Göttingen, Germany
| | - Scott R Beach
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Margo C Funk
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
- Department of Psychiatry, Brigham and Women's Hospital, Boston, MA, USA
| | - Jordan H Rosen
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
- Department of Psychiatry, Brigham and Women's Hospital, Boston, MA, USA
| | - Andres F Ramirez Gamero
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Rebecca A Karlson
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
| | - Jeff C Huffman
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Christopher M Celano
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
- Department of Psychiatry, Harvard Medical School, Boston, MA, USA
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Pappone C, Ciconte G, Vicedomini G, Anastasia L, Santinelli V. Epicardial arrhythmogenic substrate in long QT syndrome. Heart Rhythm 2023; 20:1782-1784. [PMID: 38040481 DOI: 10.1016/j.hrthm.2023.07.054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/05/2023] [Accepted: 07/08/2023] [Indexed: 12/03/2023]
Affiliation(s)
- Carlo Pappone
- Arrhythmia and Electrophysiology Center, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy; Institute of Molecular and Translational Cardiology (IMTC), San Donato Milanese, Milan, Italy.
| | - Giuseppe Ciconte
- Arrhythmia and Electrophysiology Center, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy; Institute of Molecular and Translational Cardiology (IMTC), San Donato Milanese, Milan, Italy
| | - Gabriele Vicedomini
- Arrhythmia and Electrophysiology Center, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | - Luigi Anastasia
- Arrhythmia and Electrophysiology Center, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy; Institute of Molecular and Translational Cardiology (IMTC), San Donato Milanese, Milan, Italy
| | - Vincenzo Santinelli
- Arrhythmia and Electrophysiology Center, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
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Suna G, Mellor GJ. Explaining the Unexplained: A Practical Approach to Investigating the Cardiac Arrest Survivor. Arrhythm Electrophysiol Rev 2023; 12:e27. [PMID: 38124802 PMCID: PMC10731537 DOI: 10.15420/aer.2023.06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Accepted: 10/12/2023] [Indexed: 12/23/2023] Open
Abstract
Sudden cardiac arrest (SCA) is a common cause of death. The majority of SCA is caused by ventricular arrhythmia due to underlying CHD. Aborted SCA with no apparent diagnosis after initial assessment with ECG, echocardiography and coronary assessment is referred to as unexplained cardiac arrest (UCA). Systematic evaluation of such patients may reveal a specific diagnosis in up to half of patients before a diagnosis of idiopathic VF is assigned. Specific diagnoses include inherited cardiac conditions, such as latent cardiomyopathies or inherited primary electrical disease. Identifying the cause of UCA is therefore not only critical for appropriate management of the SCA survivors to prevent recurrence, but also for their family members who may be at risk of the same condition. This review provides a tiered, systematic approach for the investigation of UCA.
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Affiliation(s)
- Gonca Suna
- Cardiology Department, Royal Papworth Hospital NHS Foundation Trust Cambridge, UK
| | - Greg J Mellor
- Cardiology Department, Royal Papworth Hospital NHS Foundation Trust Cambridge, UK
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15
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Abrahams T, Davies B, Laksman Z, Sy RW, Postema PG, Wilde AAM, Krahn AD, Han HC. Provocation testing in congenital long QT syndrome: A practical guide. Heart Rhythm 2023; 20:1570-1582. [PMID: 37481219 DOI: 10.1016/j.hrthm.2023.07.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/01/2023] [Accepted: 07/14/2023] [Indexed: 07/24/2023]
Abstract
Congenital long QT syndrome (LQTS) is a hereditary cardiac channelopathy with an estimated prevalence of 1 in 2500. A prolonged resting QT interval corrected for heart rate (QTc interval) remains a key diagnostic component; however, the QTc value may be normal in up to 40% of patients with genotype-positive LQTS and borderline in a further 30%. Provocation of QTc prolongation and T-wave changes may be pivotal to unmasking the diagnosis and useful in predicting genotype. LQTS provocation testing involves assessment of repolarization during and after exercise, in response to changes in heart rate or autonomic tone, with patients with LQTS exhibiting a maladaptive repolarization response. We review the utility and strengths and limitations of 4 forms of provocation testing-stand-up test, exercise stress test, epinephrine challenge, and mental stress test-in diagnosing LQTS and provide some practical guidance for performing provocation testing. Ultimately, exercise testing, when feasible, is the most useful form of provocation testing when considering diagnostic sensitivity and specificity.
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Affiliation(s)
- Timothy Abrahams
- Victorian Heart Institute & Monash Health Heart, Victorian Heart Hospital, Monash University, Melbourne, Victoria, Australia
| | - Brianna Davies
- Center for Cardiovascular Innovation, Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Zachary Laksman
- Center for Cardiovascular Innovation, Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Raymond W Sy
- Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Pieter G Postema
- Department of Cardiology, Amsterdam UMC location University of Amsterdam, Amsterdam, The Netherlands; Heart Failure & Arrhythmias, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands; European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), Academic Medical Center, Amsterdam, The Netherlands
| | - Arthur A M Wilde
- Department of Cardiology, Amsterdam UMC location University of Amsterdam, Amsterdam, The Netherlands; Heart Failure & Arrhythmias, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands; European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart (ERN GUARD-Heart), Academic Medical Center, Amsterdam, The Netherlands
| | - Andrew D Krahn
- Center for Cardiovascular Innovation, Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Hui-Chen Han
- Victorian Heart Institute & Monash Health Heart, Victorian Heart Hospital, Monash University, Melbourne, Victoria, Australia.
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Arteyeva NV, Komarov IA, Azarov JE. Action potential morphology affects T-wave symmetry (simulation study). J Electrocardiol 2023; 81:237-243. [PMID: 37844373 DOI: 10.1016/j.jelectrocard.2023.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/06/2023] [Accepted: 10/10/2023] [Indexed: 10/18/2023]
Abstract
BACKGROUND Assessing T-wave symmetry in addition to QT subintervals measurements can provide novel independent data about ventricular repolarization abnormalities linked with arrhythmogenesis. However, the causes of the changes of T-wave symmetry are not completely understood. In silico studies showed that the more symmetrical T-waves were associated with shorter action potential duration (APD) and larger dispersion of ventricular repolarization (DOR). The aim of present simulation was to study the association between T-wave symmetry and action potential (AP) shape. METHODS ECGs were simulated using a cellular automata model shaped as a ventricular wall segment, and two biophysically-detailed models of ventricular AP - the rabbit and the human. The symmetry ratio (SR) was calculated as a T-wave onset-peak to peak-end area ratio. The individual and combined effects of APD, DOR and AP shape on SR were simulated. To study the effect of AP shape, different APs from triangulated to rectangular were simulated. RESULTS The simulations showed that AP shape along with APD and DOR contributes much to T-wave symmetry. APs with a flat phase 3 (triangulated) produced asymmetrical T-waves (SR ≥ 1.5) in all simulations, except the shortest APD range. APs with a rapid phase 3 (rectangular) were associated with more symmetrical T-waves (SR ≤ =1) both at the short and the long APDs. CONCLUSION SR marker in combination with the standard ECG parameters (QT interval, Tpeak-Tend interval) may be useful to identify the proarrhythmic triangulated AP shape.
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Affiliation(s)
- Natalia V Arteyeva
- Department of Cardiac Physiology, Institute of Physiology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 50, Pervomayskaya st, Syktyvkar 167982, Russia.
| | - Ilia A Komarov
- Department of Cardiac Physiology, Institute of Physiology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 50, Pervomayskaya st, Syktyvkar 167982, Russia
| | - Jan E Azarov
- Department of Cardiac Physiology, Institute of Physiology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 50, Pervomayskaya st, Syktyvkar 167982, Russia; Department of Physiology, Medical Institute of Pitirim Sorokin, Syktyvkar State University, 11, Babushkin st, Syktyvkar 167000, Russia
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Dubey N, Ubhadiya TJ, Garg VS, Vadnagara H, Sojitra MH, Gandhi SK, Patel P. Unlocking the Potential of Left Cardiac Sympathetic Denervation: A Scoping Review of a Promising Approach for Long QT Syndrome. Cureus 2023; 15:e47306. [PMID: 38021601 PMCID: PMC10656634 DOI: 10.7759/cureus.47306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2023] [Indexed: 12/01/2023] Open
Abstract
Left cardiac sympathetic denervation (LCSD) has emerged as an alternative therapy for individuals diagnosed with long QT syndrome (LQTS), a genetic disorder characterized by abnormal electrical activity in the heart and sudden cardiac death (SCD). This review examines the history and rationale behind LCSD in LQTS treatment, as well as the procedure, its efficacy, and indications along with the adverse effects that may be associated with it. LQTS presents with prolonged QT intervals on an electrocardiogram and can manifest as seizures, fainting, and SCD. Beta-blockers are the primary treatment for LQTS but some patients do not respond well to these medications or experience side effects. Additionally, implantable cardioverter-defibrillators (ICDs) are not always effective in preventing arrhythmias and can lead to complications. LCSD might offer an alternative approach by disrupting sympathetic activity in the heart. In humans, LCSD reduces the release of norepinephrine, normalizes the QT interval, and decreases the likelihood of life-threatening heart rhythms. The procedure does not impair heart rate or cardiac function due to the compensatory effects of the right cardiac sympathetic nerves. The surgical procedure for LCSD involves the removal of the lower half of the stellate ganglion and thoracic ganglia. Complete denervation is essential for optimal outcomes, while incomplete procedures are considered unacceptable. Traditional and minimally invasive approaches, such as video-assisted thoracic surgery (VATS), are available, with VATS offering shorter hospital stays and fewer complications. In conclusion, LCSD provides a viable treatment option for individuals with LQTS who do not respond well to beta-blockers or require additional protection beyond medication or ICDs. Further research and clinical experience are needed to enhance its acceptance and implementation in routine practice.
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Affiliation(s)
- Nidhi Dubey
- Department of Internal Medicine, Civil Hospital Ahmedabad, Ahmedabad, IND
| | - Tyagi J Ubhadiya
- Department of Internal Medicine, Civil Hospital Ahmedabad, Ahmedabad, IND
| | - Vasudha S Garg
- Department of Internal Medicine, Civil Hospital Ahmedabad, Ahmedabad, IND
| | - Harsh Vadnagara
- Department of Internal Medicine, Civil Hospital Ahmedabad, Ahmedabad, IND
| | - Mihir H Sojitra
- Department of Neurology, Civil Hospital Ahmedabad, Ahmedabad, IND
| | - Siddharth Kamal Gandhi
- Department of Internal Medicine, Shri M. P. Shah Government Medical College, Jamnagar, IND
| | - Priyansh Patel
- Department of Internal Medicine, Medical College Baroda, Vadodara, IND
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Hansom S, Laksman Z. Implantable Devices in Genetic Heart Disease: Disease-Specific Device Selection and Programming. Card Electrophysiol Clin 2023; 15:249-260. [PMID: 37558296 DOI: 10.1016/j.ccep.2023.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
Diagnosis and risk stratification of rare genetic heart diseases remains clinically challenging. In many cases, there are few data and insufficient numbers to support randomized controlled trials. While implantable cardioverter defibrillator (ICD) use is vital to protect higher-risk individuals from life-threatening ventricular arrhythmias, low-risk individuals also require protection from unnecessary ICDs and their associated complications. Once an ICD has been implanted, appropriate device programming is essential to ensure maximal protection while balancing the risks of inappropriate therapy.
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Affiliation(s)
- Simon Hansom
- Division of Cardiology, Arrhythmia Service, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, Ontario K1Y 4W7, Canada
| | - Zachary Laksman
- Department of Medicine and the School of Biomedical Engineering, Room 211 - 1033 Davie Street, Vancouver, British Columbia V6E 1M7, Canada.
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Lima B, Razmjouei S, Bajwa MT, Shahzad Z, Shoewu OA, Ijaz O, Mange P, Khanal S, Gebregiorgis T. Polypharmacy, Gender Disparities, and Ethnic and Racial Predispositions in Long QT Syndrome: An In-Depth Review. Cureus 2023; 15:e46009. [PMID: 37900391 PMCID: PMC10600617 DOI: 10.7759/cureus.46009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2023] [Indexed: 10/31/2023] Open
Abstract
Long QT syndrome (LQTS) is a complex disorder of cardiac electrophysiology. It is characterized by delayed myocardial polarization leading to QT prolongation and alterations on the ST segment and T wave visible on electrocardiogram (ECG). Syncope is a common manifestation, and torsade de pointes (TdP) can lead to sudden cardiac death. Three major LQTS genes (KCI31, KCNH2, and SCN5) lead to most of the cases of LQTS. Lifestyle modifications, beta blockers, and implantable cardioverter defibrillator (ICD) placement are the main treatments for LQTS. Polypharmacy, including QT-prolonging drugs, has been shown to worsen LQTS. The impact on potassium channels and the human ether-a-go-go-related gene (hERG) is the mechanism behind the QT interval prolongation caused by these medications. There is an increased incidence of LQTS among African-American men and women as compared to Caucasians. Women with LQTS tend to have a higher mortality rate from the condition, especially during menstruation and shortly after giving birth. Genetic testing is reserved to those patientswho exhibit either a strong clinical index of suspicion or experience persistent QT prolongation despite their lack of symptoms. Knowing the genetics, racial, and gender discrepancies can help improve patient management and a better comprehension on each case. Proper understanding of how ion channels function and their interaction with medications will lead to a better comprehension and to develop effective forms to treat those patients.
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Affiliation(s)
- Bruno Lima
- Medicine, University of Grande Rio, Rio Grande, USA
| | - Soha Razmjouei
- Anesthesiology, Case Western Reserve University School of Medicine, Cleveland, USA
| | | | - Zoha Shahzad
- Internal Medicine, Fatima Jinnah Medical University, Lahore, PAK
| | | | - Osama Ijaz
- Internal Medicine, Services Hospital Lahore, Lahore, PAK
| | - Pooja Mange
- Internal Medicine, K.J. Somaiya Hospital and Research Center, Mumbai, IND
| | | | - Tsion Gebregiorgis
- General Practice, Addis Ababa University Medical Faculty, Addis Ababa, ETH
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20
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Zhao N, Yu Z, Cai Z, Chen W, He X, Huo Z, Lin X. Novel combinations of variations in KCNQ1 were associated with patients with long QT syndrome or Jervell and Lange-Nielsen syndrome. BMC Cardiovasc Disord 2023; 23:399. [PMID: 37568094 PMCID: PMC10422715 DOI: 10.1186/s12872-023-03417-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
OBJECTIVES Long QT syndrome (LQTS) is one of the primary causes of sudden cardiac death (SCD) in youth. Studies have identified mutations in ion channel genes as key players in the pathogenesis of LQTS. However, the specific etiology in individual families remains unknown. METHODS Three unrelated Chinese pedigrees diagnosed with LQTS or Jervell and Lange-Nielsen syndrome (JLNS) were recruited clinically. Whole exome sequencing (WES) was performed and further validated by multiplex ligation-dependent probe amplification (MLPA) and Sanger sequencing. RESULTS All of the probands in our study experienced syncope episodes and featured typically prolonged QTc-intervals. Two probands also presented with congenital hearing loss and iron-deficiency anemia and thus were diagnosed with JLNS. A total of five different variants in KCNQ1, encoding a subunit of the voltage-gated potassium channel, were identified in 3 probands. The heterozygous variants, KCNQ1 c.749T > C was responsible for LQTS in Case 1, transmitting in an autosomal dominant pattern. Two patterns of compound heterozygous variants were responsible for JLNS, including a large deletion causing loss of the exon 16 and missense variant c.1663 C > T in Case 2, and splicing variant c.605-2 A > G and frame-shift variant c.1265del in Case 3. To our knowledge, the compound heterozygous mutations containing a large deletion and missense variant were first reported in patients with JLNS. CONCLUSION Our study expanded the LQTS genetic spectrum, thus favoring disease screening and diagnosis, personalized treatment, and genetic consultation.
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Affiliation(s)
- Nongnong Zhao
- Department of Cardiology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
- Yuyao People's Hospital of Zhejiang Province, Yuyao, Ningbo, 315400, Zhejiang, China
| | - Zhengyang Yu
- Department of Cardiology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Zhejun Cai
- Department of Cardiology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Wenai Chen
- Department of Cardiology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Xiaopeng He
- Department of Cardiology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Zhaoxia Huo
- Experimental Teaching Center, School of Basic Medical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, Zhejiang, China.
| | - Xiaoping Lin
- Department of Cardiology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China.
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Calò L, Lanza O, Crescenzi C, Parisi C, Panattoni G, Martino A, Rebecchi M, Tarzia P, Ciampi P, Romeo F, Canestrelli S, Silvetti E, De Ruvo E. The value of the 12-lead electrocardiogram in the prediction of sudden cardiac death. Eur Heart J Suppl 2023; 25:C218-C226. [PMID: 37125292 PMCID: PMC10132628 DOI: 10.1093/eurheartjsupp/suad023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Sudden cardiac death (SCD) can be caused by several clinical conditions, overt or misconceived, which recognize different pathophysiologies determining the development of fatal arrhythmic events. In the various forms of structural heart disease such as ischaemic heart disease, cardiomyopathies (e.g. hypertrophic cardiomyopathy, dilated cardiomyopathy, and arrhythmogenic cardiomyopathy), channelopathies (e.g. long-QT syndrome, congenital short QT, Brugada syndrome, early repolarization (ER) syndrome, and idiopathic ventricular fibrillation) but also in the apparently healthy subject, the 12-lead electrocardiogram (ECG) has proved, over the years, to be a reliable and readily available method for stratifying the risk of adverse arrhythmic events and consequently SCD. Several electrocardiographic markers have been shown to be associated with adverse outcomes in different types of patients. Although with different sensitivity and specificity in each clinical condition, depolarization abnormalities, such as QRS fragmentation, Q waves, QRS duration, left posterior fascicular block, low QRS voltage, and left ventricular hypertrophy and similarly repolarization abnormalities as ER pattern, T wave alternans, QT interval, and QT dispersion, have shown significant efficacy in predicting SCD. Despite the advancement of techniques especially in the field of imaging, the correct interpretation of the 12-lead ECG remains, therefore, an effective tool for assessing the possible prognostic outcome in terms of arrhythmic risk and SCD in different types of patients.
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Affiliation(s)
- Leonardo Calò
- Corresponding author. Tel: +39 06 23188406, Fax: +39 06 23188410,
| | - Oreste Lanza
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Cinzia Crescenzi
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Cristian Parisi
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Germana Panattoni
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Annamaria Martino
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Marco Rebecchi
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Pierpaolo Tarzia
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Pellegrino Ciampi
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Fabiana Romeo
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Stefano Canestrelli
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Elisa Silvetti
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
| | - Ermenegildo De Ruvo
- Division of Cardiology, Policlinico Casilino, Via Casilina 1049, 00169 Rome, Italy
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Lancaster MC, Chen HH, Shoemaker MB, Fleming MR, Baker JT, Polikowsky HG, Samuels DC, Huff CD, Roden DM, Below JE. Detection of distant familial relatedness in biobanks for identification of undiagnosed carriers of a Mendelian disease variant: application to Long QT syndrome. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.04.19.23288831. [PMID: 37163006 PMCID: PMC10168417 DOI: 10.1101/2023.04.19.23288831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Importance The diagnosis and study of rare genetic disease is often limited to referral populations, leading to underdiagnosis and a biased assessment of penetrance and phenotype. Objective To develop a generalizable method of genotype inference based on distant relatedness and to deploy this to identify undiagnosed Type 5 Long QT Syndrome (LQT5) rare variant carriers in a non-referral population. Participants We identified 9 LQT5 probands and 3 first-degree relatives referred to a single Genetic Arrhythmia clinic, each carrying D76N (p.Asp76Asn), the most common variant implicated in LQT5. The non-referral population consisted of 69,879 ancestry-matched subjects in BioVU, a large biobank that links electronic health records to dense array data. Participants were enrolled from 2007-2022. Data analysis was performed in 2022. Exposures We developed and applied a novel approach to genotype inference (Distant Relatedness for Identification and Variant Evaluation, or DRIVE) to identify shared, identical-by-descent (IBD) large chromosomal segments in array data. Main Outcomes and Measures We sought to establish genetic relatedness among the probands and to use genomic segments underlying D76N to identify other potential carriers in BioVU. We then further studied the role of D76N in LQT5 pathogenesis. Results Genetic reconstruction of pedigrees and distant relatedness detection among clinic probands using DRIVE revealed shared recent common ancestry and identified a single long shared haplotype. Interrogation of the non-referral population in BioVU identified a further 23 subjects sharing this haplotype, and sequencing confirmed D76N carrier status in 22, all previously undiagnosed with LQT5. The QTc was prolonged in D76N carriers compared to BioVU controls, with 40% penetrance of QTc ≥ 480 msec. Among D76N carriers, a QTc polygenic score was additively associated with QTc prolongation. Conclusions and Relevance Detection of IBD shared chromosomal segments around D76N enabled identification of distantly related and previously undiagnosed rare-variant carriers, demonstrated the contribution of polygenic risk to monogenic disease penetrance, and further established LQT5 as a primary arrhythmia disorder. Analysis of shared chromosomal regions spanning disease-causing mutations can identify undiagnosed cases of genetic diseases.
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Affiliation(s)
| | - Hung-Hsin Chen
- Vanderbilt University Medical Center, Nashville, Tennessee
| | | | | | - James T Baker
- Vanderbilt University Medical Center, Nashville, Tennessee
| | | | | | - Chad D Huff
- University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Dan M Roden
- Vanderbilt University Medical Center, Nashville, Tennessee
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Miller JA, Moise N, Weinberg SH. Modeling incomplete penetrance in long QT syndrome type 3 through ion channel heterogeneity: an in silico population study. Am J Physiol Heart Circ Physiol 2023; 324:H179-H197. [PMID: 36487185 PMCID: PMC10072004 DOI: 10.1152/ajpheart.00430.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 11/16/2022] [Accepted: 11/29/2022] [Indexed: 12/14/2022]
Abstract
Many cardiac diseases are characterized by an increased late sodium current, including heart failure, hypertrophic cardiomyopathy, and inherited long QT syndrome type 3 (LQT3). The late sodium current in LQT3 is caused by a gain-of-function mutation in the voltage-gated sodium channel Nav1.5. Despite a well-defined genetic cause of LQT3, treatment remains inconsistent because of incomplete penetrance of the mutation and variability of antiarrhythmic efficacy. Here, we investigate the relationship between LQT3-associated mutation incomplete penetrance and variability in ion channel expression, simulating a population of 1,000 individuals with the O'Hara-Rudy model of the human ventricular myocyte. We first simulate healthy electrical activity (i.e., in the absence of a mutation) and then incorporate heterozygous expression for three LQT3-associated mutations (Y1795C, I1768V, and ΔKPQ), to directly compare the effects of each mutation on individuals across a diverse population. For all mutations, we find that susceptibility, defined by either the presence of an early afterdepolarization (EAD) or prolonged action potential duration (APD), primarily depends on the balance between the conductance of IKr and INa, for which individuals with a higher IKr-to-INa ratio are less susceptible. Furthermore, we find distinct differences across the population, observing individuals susceptible to zero, one, two, or all three mutations. Individuals tend to be less susceptible with an appropriate balance of repolarizing currents, typically via increased IKs or IK1. Interestingly, the more critical repolarizing current is mutation specific. We conclude that the balance between key currents plays a significant role in mutant-specific presentation of the disease phenotype in LQT3.NEW & NOTEWORTHY An in silico population approach investigates the relationship between variability in ion channel expression and gain-of-function mutations in the voltage-gated sodium channel associated with the congenital disorder long QT syndrome type 3 (LQT3). We find that ion channel variability can contribute to incomplete penetrance of the mutation, with mutant-specific differences in ion channel conductances leading to susceptibility to proarrhythmic action potential duration prolongation or early afterdepolarizations.
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Affiliation(s)
- Jacob A Miller
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
| | - Nicolae Moise
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
| | - Seth H Weinberg
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
- Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio
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Ma J, Niklewski PJ, Wang HS. Acute exposure to low-dose bisphenol A delays cardiac repolarization in female canine heart - Implication for proarrhythmic toxicity in large animals. Food Chem Toxicol 2023; 172:113589. [PMID: 36584932 PMCID: PMC9852101 DOI: 10.1016/j.fct.2022.113589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 12/12/2022] [Accepted: 12/24/2022] [Indexed: 12/29/2022]
Abstract
Bisphenol A (BPA) is a common environmental chemical with a range of potential adverse health effects. The impact of environmentally-relevant low dose of BPA on the electrical properties of the hearts of large animals (e.g., dog, human) is poorly defined. Perturbation of cardiac electrical properties is a key arrhythmogenic mechanism. In particular, delay of ventricular repolarization and prolongation of the QT interval of the electrocardiogram is a marker for the risk of malignant arrhythmias. We examined the acute effect of 10-9 M BPA on the electrical properties of female canine ventricular myocytes and tissues. BPA rapidly delayed action potential repolarization and prolonged action potential duration (APD). The dose response curve of BPA on APD was nonmonotonic. BPA rapidly inhibited the IKr K+ current and ICaL Ca2+ current. Computational modeling indicated that the effect of BPA on APD can be accounted for by its suppression of IKr. At the tissue level, BPA acutely prolonged the QT interval in 4 left ventricular wedges. ERβ signaling contributed to the acute effects of BPA on ventricular repolarization. Our results demonstrate that BPA has QT prolongation liability in female canine hearts. These findings have implication for the potential proarrhythmic cardiac toxicity of BPA in large animals.
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Affiliation(s)
- Jianyong Ma
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Paul J Niklewski
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Hong-Sheng Wang
- Department of Pharmacology and Systems Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA.
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Li J. Long QT syndrome: long story short. Eur Heart J 2022; 43:4976-4977. [PMID: 36254679 DOI: 10.1093/eurheartj/ehac551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Affiliation(s)
- Jin Li
- Department of Cardiology, University Heart Center, University Hospital Zurich, University of Zurich, Raemistrasse 100, 8091 Zurich, Switzerland
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Dye CA, Engelstein E, Swearingen S, Murphy J, Larsen T, Volgman AS. Sex, Rhythm & Death: The effect of sexual activity on cardiac arrhythmias and sudden cardiac death. Front Cardiovasc Med 2022; 9:987247. [PMID: 36225957 PMCID: PMC9548576 DOI: 10.3389/fcvm.2022.987247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/26/2022] [Indexed: 11/13/2022] Open
Abstract
Arrhythmias and sudden cardiac death with sexual activity are rare. However, the demographics are changing regarding the cardiovascular patients at risk for these events. Recent studies have highlighted that the individuals having cardiac events during sexual activity are becoming younger, with a higher proportion of female decedents than previously described. There needs to be an open dialog between the cardiovascular team and the cardiac patient to provide the education and reassurance necessary for cardiovascular patients to participate in sexual intercourse safely. This paper reviews how sexual activity can lead to an increase in cardiac arrhythmias and sudden cardiac arrest in patients that are not medically optimized or are unaware of their underlying cardiac condition. The most common cardiovascular diseases associated with sexually induced arrhythmias and arrest are discussed regarding their potential risk and the psychosocial impact of this risk on these patients. Finally, cardiovascular medications and implantable cardioverter-defibrillators (ICDs) are addressed by reviewing the literature on the safety profile of these cardiac interventions in this patient population. Overall, sexual activity is safe for most cardiac patients, and providing proper education to the patient and their partner can improve the safety profile for patients with higher risk cardiovascular conditions. To give the appropriate education and reassurance necessary, cardiovascular team members need an understanding of the pathophysiology of how sexual activity can provoke arrhythmias and sudden cardiac arrest. Healthcare providers also need to build comfort in speaking to all patients and ensure that sexual partners, female patients, and those in the LGBTQIA + community receive the same access to counseling but tailored to their individual needs.
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Kekenes-Huskey PM, Burgess DE, Sun B, Bartos DC, Rozmus ER, Anderson CL, January CT, Eckhardt LL, Delisle BP. Mutation-Specific Differences in Kv7.1 ( KCNQ1) and Kv11.1 ( KCNH2) Channel Dysfunction and Long QT Syndrome Phenotypes. Int J Mol Sci 2022; 23:7389. [PMID: 35806392 PMCID: PMC9266926 DOI: 10.3390/ijms23137389] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 06/22/2022] [Accepted: 06/24/2022] [Indexed: 11/16/2022] Open
Abstract
The electrocardiogram (ECG) empowered clinician scientists to measure the electrical activity of the heart noninvasively to identify arrhythmias and heart disease. Shortly after the standardization of the 12-lead ECG for the diagnosis of heart disease, several families with autosomal recessive (Jervell and Lange-Nielsen Syndrome) and dominant (Romano-Ward Syndrome) forms of long QT syndrome (LQTS) were identified. An abnormally long heart rate-corrected QT-interval was established as a biomarker for the risk of sudden cardiac death. Since then, the International LQTS Registry was established; a phenotypic scoring system to identify LQTS patients was developed; the major genes that associate with typical forms of LQTS were identified; and guidelines for the successful management of patients advanced. In this review, we discuss the molecular and cellular mechanisms for LQTS associated with missense variants in KCNQ1 (LQT1) and KCNH2 (LQT2). We move beyond the "benign" to a "pathogenic" binary classification scheme for different KCNQ1 and KCNH2 missense variants and discuss gene- and mutation-specific differences in K+ channel dysfunction, which can predispose people to distinct clinical phenotypes (e.g., concealed, pleiotropic, severe, etc.). We conclude by discussing the emerging computational structural modeling strategies that will distinguish between dysfunctional subtypes of KCNQ1 and KCNH2 variants, with the goal of realizing a layered precision medicine approach focused on individuals.
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Affiliation(s)
- Peter M. Kekenes-Huskey
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA
| | - Don E. Burgess
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
| | - Bin Sun
- Department of Pharmacology, Harbin Medical University, Harbin 150081, China;
| | | | - Ezekiel R. Rozmus
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
| | - Corey L. Anderson
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Craig T. January
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Lee L. Eckhardt
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Brian P. Delisle
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
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