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Förster CY, Künzel SR, Shityakov S, Stavrakis S. Synergistic Effects of Weight Loss and Catheter Ablation: Can microRNAs Serve as Predictive Biomarkers for the Prevention of Atrial Fibrillation Recurrence? Int J Mol Sci 2024; 25:4689. [PMID: 38731908 PMCID: PMC11083177 DOI: 10.3390/ijms25094689] [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: 02/26/2024] [Revised: 04/23/2024] [Accepted: 04/23/2024] [Indexed: 05/13/2024] Open
Abstract
In atrial fibrillation (AF), multifactorial pathologic atrial alterations are manifested by structural and electrophysiological changes known as atrial remodeling. AF frequently develops in the context of underlying cardiac abnormalities. A critical mechanistic role played by atrial stretch is played by abnormal substrates in a number of conditions that predispose to AF, including obesity, heart failure, hypertension, and sleep apnea. The significant role of overweight and obesity in the development of AF is known; however, the differential effect of overweight, obesity, cardiovascular comorbidities, lifestyle, and other modifiable risk factors on the occurrence and recurrence of AF remains to be determined. Reverse remodeling of the atrial substrate and subsequent reduction in the AF burden by conversion into a typical sinus rhythm has been associated with weight loss through lifestyle changes or surgery. This makes it an essential pillar in the management of AF in obese patients. According to recently published research, microRNAs (miRs) may function as post-transcriptional regulators of genes involved in atrial remodeling, potentially contributing to the pathophysiology of AF. The focus of this review is on their modulation by both weight loss and catheter ablation interventions to counteract atrial remodeling in AF. Our analysis outlines the experimental and clinical evidence supporting the synergistic effects of weight loss and catheter ablation (CA) in reversing atrial electrical and structural remodeling in AF onset and in recurrent post-ablation AF by attenuating pro-thrombotic, pro-inflammatory, pro-fibrotic, arrhythmogenic, and male-sex-associated hypertrophic remodeling pathways. Furthermore, we discuss the promising role of miRs with prognostic potential as predictive biomarkers in guiding approaches to AF recurrence prevention.
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Affiliation(s)
- Carola Y. Förster
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University of Würzburg, 97080 Würzburg, Germany
| | - Stephan R. Künzel
- Institute for Transfusion Medicine, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany;
- Institute for Transfusion Medicine, German Red Cross Blood Donation Service North-East, 01307 Dresden, Germany
| | - Sergey Shityakov
- Laboratory of Chemoinformatics, Infochemistry Scientific Center, ITMO University, 197101 Saint-Petersburg, Russia;
| | - Stavros Stavrakis
- Cardiovascular Section, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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Gondal MUR, Mehmood RS, Khan RP, Malik J. Atrial myopathy. Curr Probl Cardiol 2024; 49:102381. [PMID: 38191102 DOI: 10.1016/j.cpcardiol.2024.102381] [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: 12/26/2023] [Accepted: 01/04/2024] [Indexed: 01/10/2024]
Abstract
This paper delves into the progressive concept of atrial myopathy, shedding light on its development and its impact on atrial characteristics. It extensively explores the intricate connections between atrial myopathy, atrial fibrillation (AF), and strokes. Researchers have sought additional contributors to AF-related strokes due to the absence of a clear timing correlation between paroxysmal AF episodes and strokes in patients with cardiac implantable electronic devices. Through various animal models and human investigations, a close interrelation among aging, inflammation, oxidative stress, and stretching mechanisms has been identified. These mechanisms contribute to fibrosis, alterations in electrical properties, autonomic remodeling, and a heightened pro-thrombotic state. These interconnected factors establish a detrimental cycle, exacerbating atrial myopathy and elevating the risk of sustained AF and strokes. By emphasizing the significance of atrial myopathy and the risk of strokes that are distinct from AF, the paper also discusses methods for identifying patients with atrial myopathy. Moreover, it proposes an approach to incorporate the concept of atrial myopathy into clinical practice to guide anticoagulation decisions in individuals with AF.
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Affiliation(s)
| | - Raja Sadam Mehmood
- Department of Medicine, Shifa International Hospital, Islamabad, Pakistan
| | | | - Jahanzeb Malik
- Department of Cardiovascular Medicine, Cardiovascular Analytics Group, Islamabad, Pakistan.
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3
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Rossi VA, Laptseva N, Nebunu D, Haider T, Nägele MP, Ruschitzka F, Sudano I, Flammer AJ. Impaired retinal micro-vascular function in patients with atrial fibrillation. Int J Cardiol 2024; 398:131592. [PMID: 37979794 DOI: 10.1016/j.ijcard.2023.131592] [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: 10/02/2023] [Revised: 11/01/2023] [Accepted: 11/14/2023] [Indexed: 11/20/2023]
Abstract
BACKGROUND Cardiovascular (CV) risk factors and CV diseases, in particular heart failure, are strongly associated with impaired microvascular retinal endothelial function. Whether atrial fibrillation (AF) contributes to vascular dysfunction is not clear. Therefore, the aim of this study was to investigate the impact of AF on retinal microvascular function. METHODS In this study, vascular function was measured non-invasively with flicker-light induced vasodilatation of retinal arterioles (FIDart%). Patients with a history of AF and risk factors for heart failure (HF) or heart failure (n = 69; age 67.9 ± 9.2 years, 71% male, 35% HFrEF, 56% paroxysmal, 25% persistent, 19% permanent AF), as well as age, sex and ejection fraction matched patients with absent history of AF (n = 66; age 63.4 ± 10.6 years, 67% male, 47% HFrEF) were included. Patients with AF were further divided into those with paroxysmal AF (in sinus rhythm - AFSR: n = 38, age 71.4 ± 9.2, 73% male), and those with AF at the time of the study visit. RESULTS Retinal microvascular function was impaired in patients with AF compared to patients without AF (FIDart% 1.1% [0.3-2.8] vs. 2.7% [1.3-5.1], p < 0.001). Patients currently in AF have poorer retinal microvascular function (FIDart% 0.8% [0.1-1.9) compared to patients with a history of AF but currently in SR at the time of retinal function measurement (1.5% [0.6-4.9] p = 0.017). In patients with AF, impaired retinal vascular function was independently associated with larger left atrial volume (mean 49.8 ± 18.4), even after correction for confounding factors in different models (SCR = -0. 251 to -0.256, p = 0.035-0.01). CONCLUSIONS AF in patients with heart failure is associated with impaired vascular function, even if currently in sinus rhythm. The association of retinal microvascular dysfunction with left atrial volume, a surrogate for elevated cardiac filling pressures, may further highlight the important interplay between the vasculature and elevated filling pressures in the development of AF.
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Affiliation(s)
| | | | - Delia Nebunu
- University Heart Center, University Hospital of Zurich, Switzerland
| | - Thomas Haider
- University Heart Center, University Hospital of Zurich, Switzerland
| | | | - Frank Ruschitzka
- University Heart Center, University Hospital of Zurich, Switzerland; Center for Translational and Experimental Cardiology, Schlieren, Switzerland; University of Zurich, Zurich, Switzerland
| | - Isabella Sudano
- University Heart Center, University Hospital of Zurich, Switzerland; Center for Translational and Experimental Cardiology, Schlieren, Switzerland; University of Zurich, Zurich, Switzerland
| | - Andreas J Flammer
- University Heart Center, University Hospital of Zurich, Switzerland; Center for Translational and Experimental Cardiology, Schlieren, Switzerland; University of Zurich, Zurich, Switzerland.
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4
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Burnham HV, Cizauskas HE, Barefield DY. Fine tuning contractility: atrial sarcomere function in health and disease. Am J Physiol Heart Circ Physiol 2024; 326:H568-H583. [PMID: 38156887 DOI: 10.1152/ajpheart.00252.2023] [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: 05/02/2023] [Revised: 12/20/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024]
Abstract
The molecular mechanisms of sarcomere proteins underlie the contractile function of the heart. Although our understanding of the sarcomere has grown tremendously, the focus has been on ventricular sarcomere isoforms due to the critical role of the ventricle in health and disease. However, atrial-specific or -enriched myofilament protein isoforms, as well as isoforms that become expressed in disease, provide insight into ways this complex molecular machine is fine-tuned. Here, we explore how atrial-enriched sarcomere protein composition modulates contractile function to fulfill the physiological requirements of atrial function. We review how atrial dysfunction negatively affects the ventricle and the many cardiovascular diseases that have atrial dysfunction as a comorbidity. We also cover the pathophysiology of mutations in atrial-enriched contractile proteins and how they can cause primary atrial myopathies. Finally, we explore what is known about contractile function in various forms of atrial fibrillation. The differences in atrial function in health and disease underscore the importance of better studying atrial contractility, especially as therapeutics currently in development to modulate cardiac contractility may have different effects on atrial sarcomere function.
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Affiliation(s)
- Hope V Burnham
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, United States
| | - Hannah E Cizauskas
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, United States
| | - David Y Barefield
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, United States
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5
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Águila‐Gordo D, Jiménez‐Díaz J, Negreira‐Caamaño M, Martínez‐Del Rio J, Ruiz‐Pastor C, Sánchez Pérez I, Piqueras‐Flores J. Usefulness of risk scores and predictors of atrial fibrillation recurrence after elective electrical cardioversion. Ann Noninvasive Electrocardiol 2024; 29:e13095. [PMID: 37986620 PMCID: PMC10770812 DOI: 10.1111/anec.13095] [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: 05/20/2023] [Revised: 10/19/2023] [Accepted: 10/27/2023] [Indexed: 11/22/2023] Open
Abstract
INTRODUCTION Electrical cardioversion (ECV) is a frequently used procedure for restoring sinus rhythm in atrial fibrillation (AF); however, the rate of recurrence is high. The identification of patients at high risk of recurrence could influence the decision-making process. The present study evaluates the predictive value of risk scores in atrial fibrillation recurrence after elective electrical cardioversion. METHODS Unicentric, observational, and prospective study of adult patients who have undergone an elective ECV as rhythm control strategy between July 2017 and September 2022. RESULTS From the 283 analyzed patients (mean age 63.95 ± 10.76212, 74.9% male); 99 had paroxysmal AF (35%) and 159 (59%) presented AF recurrence during a follow-up of 6 months. In patients with post-ECV AF recurrence, the period of time from diagnosis until the performance of the procedure was longer (393 ± 891 vs. 195 ± 527, p = .02). No paroxysmal AF (71.3% vs. 57.8%, p = .02) and LA dilatation with >40 mL/m2 (35.9% vs. 23.3%, p = .02) volumes were more frequent within these patients. AF recurrence was more frequent in patients who had previous ECV (HR = 1.32; 95% CI: 1.12-2.35; p = .01) and more than 1 shock to recover sinus rhythm (HR = 1.62; 95% CI: 1.07-1.63; p = .01). The SLAC, ALARMEc, ATLAS, and CAAP-AF scores were statistically significant, although with a moderate predictive capacity for post-ECV recurrence. CONCLUSIONS Risk scores analyzed showed a modest value predicting AF recurrence after ECV. Previous ECV, and greater difficulty in restoring SR were independent predictors of recurrence.
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Affiliation(s)
- Daniel Águila‐Gordo
- Cardiology DepartmentHospital General Universitario de Ciudad RealCiudad RealSpain
| | - Javier Jiménez‐Díaz
- Arrhythmia Unit, Cardiology DepartmentHospital General Universitario de Ciudad RealCiudad RealSpain
| | | | | | | | - Ignacio Sánchez Pérez
- Hemodynamics and Interventional Cardiology Unit, Cardiology DepartmentHospital General Universitario de Ciudad RealCiudad RealSpain
| | - Jesús Piqueras‐Flores
- Medicine FacultyCastilla La‐Mancha UniversityCiudad RealSpain
- Cardiomyopathies and Inherited Disease Unit, Cardiology DepartmentHospital General Universitario de Ciudad RealCiudad RealSpain
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Meloni A, Pistoia L, Ricchi P, Positano V, Longo F, Borsellino Z, Cecinati V, Messina G, Corigliano E, Rosso R, Righi R, Peritore G, Renne S, Vallone A, Cademartiri F. Pancreatic T2* Magnetic Resonance Imaging for Prediction of Cardiac Arrhythmias in Transfusion-Dependent Thalassemia. J Clin Med 2023; 12:6015. [PMID: 37762955 PMCID: PMC10531669 DOI: 10.3390/jcm12186015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/08/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
We assessed the value of pancreatic T2* magnetic resonance imaging (MRI) for predicting cardiac events from a large prospective database of transfusion-dependent thalassemia (TDT) patients. We considered 813 TDT patients (36.47 ± 10.71 years, 54.6% females) enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network. MRI was used to measure hepatic, pancreatic, and cardiac iron overload (IO), to assess biventricular function and atrial dimensions, and to detect replacement myocardial fibrosis. The mean follow-up was 50.51 ± 19.75 months. Cardiac complications were recorded in 21 (2.6%) patients: one with heart failure (HF) and 20 with arrhythmias. The single patient who developed HF had, at the baseline MRI, a reduced pancreas T2*. Out of the 20 recorded arrhythmias, 17 were supraventricular. Pancreatic T2* values were a significant predictor of future arrhythmia-related events (hazard ratio = 0.89; p = 0.015). Pancreas T2* remained significantly associated with future arrhythmias after adjusting for any other univariate predictor (age and male sex, diabetes, history of previous arrhythmias, or left atrial area index). According to the receiver-operating characteristic curve analysis for arrhythmias, a pancreas T2* < 6.73 ms was the optimal cut-off value. In TDT, pancreatic iron levels had significant prognostic power for arrhythmias. Regular monitoring and the development of targeted interventions to manage pancreatic IO may help improve patient outcomes.
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Affiliation(s)
- Antonella Meloni
- Department of Radiology, Fondazione Gabriele Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (L.P.); (V.P.)
- Unità Operativa Complessa Bioingegneria, Fondazione Gabriele Monasterio CNR-Regione Toscana, 56124 Pisa, Italy
| | - Laura Pistoia
- Department of Radiology, Fondazione Gabriele Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (L.P.); (V.P.)
- Unità Operativa Semplice a Valenza Dipartimentale Ricerca Clinica, Fondazione Gabriele Monasterio CNR-Regione Toscana, 56124 Pisa, Italy
| | - Paolo Ricchi
- Unità Operativa Semplice Dipartimentale Malattie Rare del Globulo Rosso, Azienda Ospedaliera di Rilievo Nazionale “Antonio Cardarelli”, 80131 Napoli, Italy;
| | - Vincenzo Positano
- Department of Radiology, Fondazione Gabriele Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (L.P.); (V.P.)
- Unità Operativa Complessa Bioingegneria, Fondazione Gabriele Monasterio CNR-Regione Toscana, 56124 Pisa, Italy
| | - Filomena Longo
- Unità Operativa Day Hospital della Talassemia e delle Emoglobinopatie, Azienda Ospedaliero-Universitaria “S. Anna”, 44124 Cona, Italy;
| | - Zelia Borsellino
- Unità Operativa Complessa Ematologia con Talassemia, ARNAS Civico “Benfratelli-Di Cristina”, 90134 Palermo, Italy;
| | - Valerio Cecinati
- Struttura Semplice di Microcitemia, Ospedale “Santissima Annunziata”, 74123 Taranto, Italy;
| | - Giuseppe Messina
- Centro Microcitemie, Grande Ospedale Metropolitano “Bianchi-Melacrino-Morelli”, 89100 Reggio Calabria, Italy;
| | - Elisabetta Corigliano
- Ematologia Microcitemia, Ospedale San Giovanni di Dio—ASP Crotone, 88900 Crotone, Italy;
| | - Rosamaria Rosso
- Unità Operativa Talassemie ed Emoglobinopatie, Azienda Ospedaliero-Universitaria Policlinico “Vittorio Emanuele”, 95100 Catania, Italy;
| | - Riccardo Righi
- Diagnostica per Immagini e Radiologia Interventistica, Ospedale del Delta, 44023 Lagosanto, Italy;
| | - Giuseppe Peritore
- Unità Operativa Complessa di Radiologia, ARNAS Civico “Benfratelli-Di Cristina”, 90127 Palermo, Italy;
| | - Stefania Renne
- Struttura Complessa di Cardioradiologia-UTIC, Presidio Ospedaliero “Giovanni Paolo II”, 88046 Lamezia Terme, Italy;
| | - Antonino Vallone
- Reparto di Radiologia, Azienda Ospedaliera “Garibaldi” Presidio Ospedaliero Nesima, 95126 Catania, Italy;
| | - Filippo Cademartiri
- Department of Radiology, Fondazione Gabriele Monasterio CNR-Regione Toscana, 56124 Pisa, Italy; (A.M.); (L.P.); (V.P.)
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Guglielmini C, Valente C, Romito G, Mazzoldi C, Baron Toaldo M, Goncalves Sousa M, Wolf M, Beluque T, Domenech O, Patata V, Porciello F, Ferrari P, Caivano D, Contiero B, Poser H. Risk factors for atrial fibrillation in dogs with dilated cardiomyopathy. Front Vet Sci 2023; 10:1183689. [PMID: 37228845 PMCID: PMC10203468 DOI: 10.3389/fvets.2023.1183689] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 04/21/2023] [Indexed: 05/27/2023] Open
Abstract
Introduction Atrial fibrillation secondary to dilated cardiomyopathy (DCM) frequently affects large-breed dogs. The aim of the present study was to identify risk factors for the development of atrial fibrillation in dogs of different breeds with an echocardiographic diagnosis of DCM. Methods In this multicenter retrospective study, we searched the electronic databases of five cardiology referral centers for dogs with an echocardiographic diagnosis of DCM. A comparison of clinical and echocardiographic variables was performed between dogs developing atrial fibrillation and those not developing atrial fibrillation and the ability to distinguish between these two groups of dogs was evaluated by receiver operating characteristic curve analysis. Univariate and multivariable logistic regression analysis estimated the odds ratio (OR) with 95% confidence interval (CI) of developing atrial fibrillation. Results We included 89 client-owned dogs with occult and overt echocardiographic DCM. Of these, 39 dogs (43.8%) had atrial fibrillation, 29 dogs (32.6%) maintained a sinus rhythm, and 21 dogs (23.6%) showed other cardiac arrhythmias. Left atrial diameter had high accuracy (area under the curve = 0.816, 95% CI = 0.719-0.890) to predict the development of atrial fibrillation at the cut-off of >4.66 cm. After multivariable stepwise logistic regression analysis, only increased left atrial diameter (OR = 3.58, 95% CI = 1.87-6.87; p < 0.001) and presence of right atrial enlargement (OR = 4.02, 95% CI = 1.35-11.97; p = 0.013) were significant predictors of atrial fibrillation development. Discussion Atrial fibrillation is a common complication of DCM in the dog and is significantly associated with increased absolute left atrial diameter and right atrial enlargement.
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Affiliation(s)
- Carlo Guglielmini
- Department of Animal Medicine, Production and Health, University of Padua, Legnaro, Italy
| | - Carlotta Valente
- Department of Animal Medicine, Production and Health, University of Padua, Legnaro, Italy
| | - Giovanni Romito
- Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Chiara Mazzoldi
- Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Marco Baron Toaldo
- Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | | | - Marcela Wolf
- Department of Veterinary Medicine, Federal University of Paraná, Curitiba, Brazil
| | - Tamyris Beluque
- Department of Veterinary Medicine, Federal University of Paraná, Curitiba, Brazil
| | - Oriol Domenech
- Department of Cardiology, AniCura Istituto Veterinario Novara, Novara, Italy
| | - Valentina Patata
- Department of Cardiology, AniCura Istituto Veterinario Novara, Novara, Italy
| | | | - Paolo Ferrari
- Department of Veterinary Medicine, University of Perugia, Perugia, Italy
| | - Domenico Caivano
- Department of Veterinary Medicine, University of Perugia, Perugia, Italy
| | - Barbara Contiero
- Department of Animal Medicine, Production and Health, University of Padua, Legnaro, Italy
| | - Helen Poser
- Department of Animal Medicine, Production and Health, University of Padua, Legnaro, Italy
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Mboweni N, Maseko M, Tsabedze N. Heart failure with reduced ejection fraction and atrial fibrillation: a Sub-Saharan African perspective. ESC Heart Fail 2023; 10:1580-1596. [PMID: 36934444 DOI: 10.1002/ehf2.14332] [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: 06/23/2022] [Revised: 01/06/2023] [Accepted: 02/07/2023] [Indexed: 03/20/2023] Open
Abstract
Cardiovascular diseases are a well-established cause of death in high-income countries. In the last 20 years, Sub-Saharan Africa (SSA) has seen one of the sharpest increases in cardiovascular disease-related mortality, superseding that of infectious diseases, including HIV/AIDS, in South Africa. This increase is evidenced by a growing burden of heart failure and atrial fibrillation (AF) risk factors. AF is a common comorbidity of heart failure with reduced ejection fraction (HFrEF), which predisposes to an increased risk of stroke, rehospitalizations, and mortality compared with patients in sinus rhythm. AF had the largest relative increase in cardiovascular disease burden between 1990 and 2010 in SSA and the second highest (106.4%) increase in disability-adjusted life-years (DALY) between 1990 and 2017. Over the last decade, significant advancements in the management of both HFrEF and AF have emerged. However, managing HFrEF/AF remains a clinical challenge for physicians, compounded by the suboptimal efficacy of guideline-mandated pharmacotherapy in this group of patients. There may be an essential role for racial differences and genetic influence on therapeutic outcomes of HFrEF/AF patients, further complicating our overall understanding of the disease and its pathophysiology. In SSA, the lack of accurate and up-to-date epidemiological data on this subgroup of patients presents a challenge in our quest to prevent and reduce adverse outcomes. This narrative review provides a contemporary overview of the epidemiology of HFrEF/AF in SSA. We highlight important differences in the demographic and aetiological profile and the management of this subpopulation, emphasizing what is currently known and, more importantly, what is still unknown about HFrEF/AF in SSA.
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Affiliation(s)
- Nonkanyiso Mboweni
- School of Physiology, University of the Witwatersrand, Johannesburg, South Africa.,Department of Internal Medicine, Division of Cardiology, Charlotte Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, Gauteng, Johannesburg, South Africa
| | - Muzi Maseko
- School of Physiology, University of the Witwatersrand, Johannesburg, South Africa
| | - Nqoba Tsabedze
- Department of Internal Medicine, Division of Cardiology, Charlotte Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, Gauteng, Johannesburg, South Africa
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A new scoring system: PAT 2C 2H score. Its clinical use and comparison with HATCH and CHA 2DS 2-VASc scores in predicting arrhythmia recurrence after cryoballoon ablation of paroxysmal atrial fibrillation. J Interv Card Electrophysiol 2022; 65:701-710. [PMID: 35927600 DOI: 10.1007/s10840-022-01328-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 07/28/2022] [Indexed: 12/13/2022]
Abstract
BACKGROUND Several clinical risk factors and scoring systems have been proposed to predict arrhythmia recurrence after atrial fibrillation (AF) ablation. We sought to determine the ability of a new score to predict atrial arrhythmia recurrence after cryoballoon (CB) ablation of AF and whether the new score shows superior efficiency compared to previously offered scores. METHODS A total of 419 patients with paroxysmal AF who underwent their first CB ablation were included. Baseline clinical variables were analyzed, and independent predictors of recurrence at 12 months were used to develop the PAT2C2H score. The predictive capability of the new score was calculated and compared with the currently available risk scores. RESULTS Chronic obstructive pulmonary disease, left atrial dilatation, transient ischemic attack or stroke, congestive heart failure, and hypertension were independent predictors of recurrence. The PAT2C2H score which was developed from these variables had a better clinical predictive capability of arrhythmia recurrence compared to HATCH and CHA2DS2-VASc scores. With increasing PAT2C2H score and score severity (low, score of 0; moderate, score of 1-2; and high, score of ≥ 3), the proportion of patients with recurrence was increased from 7% (score = 0, severity = low) to 59% (score ≥ 3, severity = high). CONCLUSIONS The PAT2C2H score may help to identify patients who are likely benefited most from CB ablation of paroxysmal AF and who should be monitored more closely for arrhythmia recurrence at 12 months.
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10
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The Complex Relation between Atrial Cardiomyopathy and Thrombogenesis. Cells 2022; 11:cells11192963. [PMID: 36230924 PMCID: PMC9563762 DOI: 10.3390/cells11192963] [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: 07/26/2022] [Revised: 09/16/2022] [Accepted: 09/19/2022] [Indexed: 11/17/2022] Open
Abstract
Heart disease, as well as systemic metabolic alterations, can leave a ‘fingerprint’ of structural and functional changes in the atrial myocardium, leading to the onset of atrial cardiomyopathy. As demonstrated in various animal models, some of these changes, such as fibrosis, cardiomyocyte hypertrophy and fatty infiltration, can increase vulnerability to atrial fibrillation (AF), the most relevant manifestation of atrial cardiomyopathy in clinical practice. Atrial cardiomyopathy accompanying AF is associated with thromboembolic events, such as stroke. The interaction between AF and stroke appears to be far more complicated than initially believed. AF and stroke share many risk factors whose underlying pathological processes can reinforce the development and progression of both cardiovascular conditions. In this review, we summarize the main mechanisms by which atrial cardiomyopathy, preceding AF, supports thrombogenic events within the atrial cavity and myocardial interstitial space. Moreover, we report the pleiotropic effects of activated coagulation factors on atrial remodeling, which may aggravate atrial cardiomyopathy. Finally, we address the complex association between AF and stroke, which can be explained by a multidirectional causal relation between atrial cardiomyopathy and hypercoagulability.
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11
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Kirillova VV. Fluid Retention In The Pulmonary Circulation As A Cause Of Pulmonary Vein Dilatation And Atrial Fibrillation Development In Chronic Heart Failure Patients. RUSSIAN OPEN MEDICAL JOURNAL 2022. [DOI: 10.15275/rusomj.2022.0121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Objective — The study objective was to perform a transthoracic echocardiographic study of the remodeling of the left atrium and the maximum and minimum diameters of pulmonary veins, as well as remodeling regression in the process of heart failure treatment, in patients with chronic heart failure (CHF) and different forms of atrial fibrillation (AF). Material and Methods — The prospective study included patients having CHF with paroxysmal AF (n=38) and permanent AF (n=36) and without arrhythmia (n=225); the patients had their maximum and minimum diameters of the pulmonary vein measured, additionally to the standard echocardiographic protocol, before and after six months of standard therapy including a loop diuretic. Results — Structural changes in the left atrium and pulmonary veins of patients with CHF having permanent atrial fibrillation were significantly more distinct than those in patients with paroxysmal AF, in patients without arrhythmia, and in the control group. A decrease in the maximum and minimum diameters of the pulmonary vein followed by termination of AF attacks within a year of observation was detected after CHF treatment with a loop diuretic in patients with paroxysmal AF and permanent AF. Conclusion — Prescribing loop diuretics to patients with pulmonary vein dilatation detected during transthoracic echocardiography in subjects with paroxysmal AF and permanent AF results in a decrease in PV diameters and termination of AF attacks in paroxysmal AF.
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Small conductance calcium activated K + channel inhibitor decreases stretch induced vulnerability to atrial fibrillation. IJC HEART & VASCULATURE 2021; 37:100898. [PMID: 34746364 PMCID: PMC8554272 DOI: 10.1016/j.ijcha.2021.100898] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/05/2021] [Accepted: 10/16/2021] [Indexed: 12/11/2022]
Abstract
Background Atrial dilation is an important risk factor for atrial fibrillation (AF) and animal studies have found that acute atrial dilation shortens the atrial effective refractory period (AERP) and increases the risk of AF. Stretch activated ion channels (SACs) and calcium channels play a role in this. The expression profile and calcium dependent activation makes the small conductance calcium activated K+ channel (KCa2.x) a candidate for coupling stretch induced increases in intracellular calcium through K+-efflux and thereby shortening of atrial refractoriness. Objectives We hypothesized that KCa2.x channel inhibitors can prevent the stretch induced shortening of AERP and protect the heart from AF. Methods The effect of KCa2 channel inhibitor (N-(pyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (ICA) 1 µM) was investigated using the isolated perfused rabbit heart preparation. To stretch the left atrium (LA) a balloon was inserted and inflated. AERP and action potential duration (APD) were recorded before and after atrial stretch. AF was induced by burst pacing the LA at different degrees of atrial stretch. Results Stretching of the LA by increasing the balloon pressure from 0 to 20 mmHg shortened the AERP by 8.6 ± 1 ms. In comparison, the KCa2 inhibitor ICA significantly attenuated the stretch induced shortening of AERP to 2.5 ± 1.1 ms. Total AF duration increased linearly with atrial balloon pressure. This relationship was not found in the presence of ICA. ICA lowered the incidence of AF induction and total AF duration. Conclusion The KCa2 channel inhibitor ICA attenuates the acute stretch induced shortening of AERP and decreases stretch induced vulnerability to AF.
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Hu J, Zhang JJ, Li L, Wang SL, Yang HT, Fan XW, Zhang LM, Hu GL, Fu HX, Song WF, Yan LJ, Liu JJ, Wu JT, Kong B. PU.1 inhibition attenuates atrial fibrosis and atrial fibrillation vulnerability induced by angiotensin-II by reducing TGF-β1/Smads pathway activation. J Cell Mol Med 2021; 25:6746-6759. [PMID: 34132026 PMCID: PMC8278085 DOI: 10.1111/jcmm.16678] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 05/02/2021] [Accepted: 05/08/2021] [Indexed: 12/13/2022] Open
Abstract
Fibrosis serves a critical role in driving atrial remodelling‐mediated atrial fibrillation (AF). Abnormal levels of the transcription factor PU.1, a key regulator of fibrosis, are associated with cardiac injury and dysfunction following acute viral myocarditis. However, the role of PU.1 in atrial fibrosis and vulnerability to AF remain unclear. Here, an in vivo atrial fibrosis model was developed by the continuous infusion of C57 mice with subcutaneous Ang‐II, while the in vitro model comprised atrial fibroblasts that were isolated and cultured. The expression of PU.1 was significantly up‐regulated in the Ang‐II‐induced group compared with the sham/control group in vivo and in vitro. Moreover, protein expression along the TGF‐β1/Smads pathway and the proliferation and differentiation of atrial fibroblasts induced by Ang‐II were significantly higher in the Ang‐II‐induced group than in the sham/control group. These effects were attenuated by exposure to DB1976, a PU.1 inhibitor, both in vivo and in vitro. Importantly, in vitro treatment with small interfering RNA against Smad3 (key protein of TGF‐β1/Smads signalling pathway) diminished these Ang‐II‐mediated effects, and the si‐Smad3‐mediated effects were, in turn, antagonized by the addition of a PU.1‐overexpression adenoviral vector. Finally, PU.1 inhibition reduced the atrial fibrosis induced by Ang‐II and attenuated vulnerability to AF, at least in part through the TGF‐β1/Smads pathway. Overall, the study implicates PU.1 as a potential therapeutic target to inhibit Ang‐II‐induced atrial fibrosis and vulnerability to AF.
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Affiliation(s)
- Juan Hu
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Jing-Jing Zhang
- Department of Cardiology, Renmin Hospital of Wuhan University, Hubei, China
| | - Li Li
- Department of Cardiology, Qitai Farm Hospital, Xinjiang, China
| | - Shan-Ling Wang
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Hai-Tao Yang
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Xian-Wei Fan
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Lei-Ming Zhang
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Guang-Ling Hu
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Hai-Xia Fu
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Wei-Feng Song
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Li-Jie Yan
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Jing-Jing Liu
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Jin-Tao Wu
- Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, China
| | - Bin Kong
- Department of Cardiology, Renmin Hospital of Wuhan University, Hubei, China
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14
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Kajy M, Ramappa P. A Galvanizing Solution: Colonoscopy Bowel Preparation as a Trigger for Supraventricular Tachycardia. Ann Pharmacother 2021; 56:297-302. [PMID: 34121474 DOI: 10.1177/10600280211023808] [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: 11/16/2022] Open
Abstract
BACKGROUND Polyethylene glycol (PEG)-based solutions are among the most commonly used bowel preparation regimens for colonoscopy. Although these solutions are well tolerated, rare adverse cardiac events have been reported. OBJECTIVES We sought to identify the characteristics that may predispose patients to develop supraventricular tachycardia (SVT) after ingestion of GoLYTELY (PEG 3350 and electrolytes oral solution) in anticipation for their colonoscopy. METHODS We performed a retrospective observational cohort study of the electronic medical record of all patients who developed SVT after ingestion of GoLYTELY solution from April 2012 to March 2019 at the John D. Dingell VA Medical Center. Clinical data were obtained through review of medical records. RESULTS We identified 16 patients with new-onset SVT after ingestion of bowel preparation solution before undergoing the colonoscopy procedure. In all, 12 (75%) patients developed atrial fibrillation, 3 (18.8%) patients developed atrial tachycardia, and 1 patient (6.3%) developed atrial flutter. Most patients were male (93.8%), and the mean age was 69 ± 8.2 years. The commonly associated comorbidities were hypertension (87.5%), hyperlipidemia (56.3%), and diabetes (37.5%). Laboratory testing demonstrated a normal electrolyte panel and thyroid stimulating hormone level. A significant percentage of patients had dilated atria and left-ventricular hypertrophy on echocardiogram. CONCLUSION Our case series suggests that there may be certain individuals who are predisposed to development of atrial arrhythmias, more so than others, after ingestion of PEG based solution for colonoscopy. We hypothesize that the combination of atrial dilation, sympathovagal discharge, and transient electrolyte shifts at the cellular level led to the development of SVTs.
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Affiliation(s)
- Marvin Kajy
- Spectrum Health Michigan State University, Grand Rapids, MI, USA
| | - Preeti Ramappa
- John D. Dingell VA Medical Center, Wayne State University School of Medicine, Detroit, MI, USA
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15
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Pedler C, Nath L, Agne GF, Hebart M, Franklin S. Heritability estimates of atrial fibrillation in Thoroughbred racehorses in Hong Kong and Australia. J Vet Cardiol 2021; 36:115-122. [PMID: 34218164 DOI: 10.1016/j.jvc.2021.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/27/2021] [Accepted: 05/28/2021] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Atrial fibrillation (AF) is the most common performance-limiting arrhythmia of racehorses. A genetic contribution has been suggested in Standardbred racehorses but has not been investigated in Thoroughbreds. The objective of this study was to determine the heritability of AF in Thoroughbred racehorses. ANIMALS, MATERIALS AND METHODS Horses racing between 2007 and 2019 in Hong Kong and Australia that had AF detected postrace via auscultation (n = 463 cases) were compared with five randomly selected racing contemporaries (n = 2,315 controls). The ASReml-R programme was used to fit an animal model to the AF data to estimate heritability using the entire data set and a subset of horses (n = 106 cases) that had electrocardiographic confirmation of AF. Variance components were estimated assuming AF was normally distributed and on the logit-transformed scale. The risk of producing AF-affected offspring was calculated using Fisher's exact test for stallions that sired ≥10 individuals in the case-control population. RESULTS Heritability on the underlying scale was 0.064 ± 0.04 (logit animal) and 0.071 ± 0.04 (normal animal) for the entire population and 0.065 ± 0.097 (logit animal) and 0.058 ± 0.11 (normal animal) for electrocardiographic-confirmed AF cases. Of 71 stallions that sired ≥10 individuals, three were more likely to produce affected offspring (odds ratio: 4.05-7.57; p < 0.01). Age (p = 0.991), sex (p = 0.830), and year of birth (p = 0.547) did not contribute to expression. CONCLUSIONS Although some stallions were overrepresented amongst affected horses, the heritability of AF in this population of Thoroughbreds was low. Environmental and individual factors contributing to AF development require further investigation.
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Affiliation(s)
- C Pedler
- School of Animal and Veterinary Science, University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, 5353, Australia
| | - L Nath
- School of Animal and Veterinary Science, University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, 5353, Australia
| | - G F Agne
- School of Animal and Veterinary Science, University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, 5353, Australia
| | - M Hebart
- School of Animal and Veterinary Science, University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, 5353, Australia
| | - S Franklin
- School of Animal and Veterinary Science, University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, 5353, Australia.
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16
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Dudink EAMP, Bidar E, Jacobs J, van Hunnik A, Zeemering S, Weijs B, Luermans JGLM, Maesen BAE, Cheriex EC, Maessen JG, Hoorntje JCA, Schotten U, Crijns HJGM, Verheule S. The relation between the atrial blood supply and the complexity of acute atrial fibrillation. IJC HEART & VASCULATURE 2021; 34:100794. [PMID: 34095447 PMCID: PMC8164021 DOI: 10.1016/j.ijcha.2021.100794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 04/30/2021] [Accepted: 05/04/2021] [Indexed: 11/30/2022]
Abstract
Background Patients with a history of myocardial infarction and coronary artery disease (CAD) have a higher risk of developing AF. Conversely, patients with atrial fibrillation (AF) have a higher risk of developing myocardial infarction, suggesting a link in underlying pathophysiology. The aim of this study was to assess whether coronary angiographic parameters are associated with a substrate for AF in patients without a history of AF. Methods During cardiac surgery in 62 patients (coronary artery bypass grafting (CABG;n = 47), aortic valve replacement (AVR;n = 9) or CABG + AVR (n = 6)) without a history of clinical AF (age 65.4 ± 8.5 years, 26.2% female), AF was induced by burst pacing. The preoperative coronary angiogram (CAG) was assessed for the severity of CAD, and the adequacy of atrial coronary blood supply as quantified by a novel scoring system including the location and severity of right coronary artery disease in relation to the right atrial branches. Epicardial mapping of the right atrium (256 unipolar electrodes) was used to assess the complexity of induced AF. Results There was no association between the adequacy of right atrial coronary blood supply on preoperative CAG and AF complexity parameters. Multivariable analysis revealed that only increasing age (B0.232 (0.030;0.433),p = 0.03) and the presence of 3VD (B3.602 (0.187;7.018),p = 0.04) were independently associated with an increased maximal activation time difference. Conclusions The adequacy of epicardial right atrial blood supply is not associated with increased complexity of induced atrial fibrillation in patients without a history of clinical AF, while age and the extent of ventricular coronary artery disease are.
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Affiliation(s)
- Elton A M P Dudink
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiology, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Elham Bidar
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiothoracic Surgery, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands.,Maastricht University and Cardiovascular Research Institute Maastricht (CARIM), Department of Physiology, Universiteitssingel 50, 6229 ER Maastricht, the Netherlands
| | - Judith Jacobs
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiology, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Arne van Hunnik
- Maastricht University and Cardiovascular Research Institute Maastricht (CARIM), Department of Physiology, Universiteitssingel 50, 6229 ER Maastricht, the Netherlands
| | - Stef Zeemering
- Maastricht University and Cardiovascular Research Institute Maastricht (CARIM), Department of Physiology, Universiteitssingel 50, 6229 ER Maastricht, the Netherlands
| | - Bob Weijs
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiology, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Justin G L M Luermans
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiology, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Bart A E Maesen
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiothoracic Surgery, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Emile C Cheriex
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiology, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Jos G Maessen
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiothoracic Surgery, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Jan C A Hoorntje
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiology, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Ulrich Schotten
- Maastricht University and Cardiovascular Research Institute Maastricht (CARIM), Department of Physiology, Universiteitssingel 50, 6229 ER Maastricht, the Netherlands
| | - Harry J G M Crijns
- Maastricht University Medical Center (MUMC+) and Cardiovascular Research Institute Maastricht (CARIM), Department of Cardiology, P. Debyelaan 25, 6229 HX Maastricht, the Netherlands
| | - Sander Verheule
- Maastricht University and Cardiovascular Research Institute Maastricht (CARIM), Department of Physiology, Universiteitssingel 50, 6229 ER Maastricht, the Netherlands
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17
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Munro ML, van Hout I, Aitken-Buck HM, Sugunesegran R, Bhagwat K, Davis PJ, Lamberts RR, Coffey S, Soeller C, Jones PP. Human Atrial Fibrillation Is Not Associated With Remodeling of Ryanodine Receptor Clusters. Front Cell Dev Biol 2021; 9:633704. [PMID: 33718369 PMCID: PMC7947344 DOI: 10.3389/fcell.2021.633704] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 02/08/2021] [Indexed: 12/02/2022] Open
Abstract
The release of Ca2+ by ryanodine receptor (RyR2) channels is critical for cardiac function. However, abnormal RyR2 activity has been linked to the development of arrhythmias, including increased spontaneous Ca2+ release in human atrial fibrillation (AF). Clustering properties of RyR2 have been suggested to alter the activity of the channel, with remodeling of RyR2 clusters identified in pre-clinical models of AF and heart failure. Whether such remodeling occurs in human cardiac disease remains unclear. This study aimed to investigate the nanoscale organization of RyR2 clusters in AF patients – the first known study to examine this potential remodeling in diseased human cardiomyocytes. Right atrial appendage from cardiac surgery patients with paroxysmal or persistent AF, or without AF (non-AF) were examined using super-resolution (dSTORM) imaging. Significant atrial dilation and cardiomyocyte hypertrophy was observed in persistent AF patients compared to non-AF, with these two parameters significantly correlated. Interestingly, the clustering properties of RyR2 were remarkably unaltered in the AF patients. No significant differences were identified in cluster size (mean ∼18 RyR2 channels), density or channel packing within clusters between patient groups. The spatial organization of clusters throughout the cardiomyocyte was also unchanged across the groups. RyR2 clustering properties did not significantly correlate with patient characteristics. In this first study to examine nanoscale RyR2 organization in human cardiac disease, these findings indicate that RyR2 cluster remodeling is not an underlying mechanism contributing to altered channel function and subsequent arrhythmogenesis in human AF.
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Affiliation(s)
- Michelle L Munro
- Department of Physiology and HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Isabelle van Hout
- Department of Physiology and HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Hamish M Aitken-Buck
- Department of Physiology and HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | | | - Krishna Bhagwat
- Department of Cardiothoracic Surgery, Dunedin Hospital, Dunedin, New Zealand
| | - Philip J Davis
- Department of Cardiothoracic Surgery, Dunedin Hospital, Dunedin, New Zealand
| | - Regis R Lamberts
- Department of Physiology and HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Sean Coffey
- Department of Medicine and HeartOtago, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Christian Soeller
- Living Systems Institute, University of Exeter, Exeter, United Kingdom
| | - Peter P Jones
- Department of Physiology and HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
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Ravelli F, Masè M. MicroRNAs: New contributors to mechano-electric coupling and atrial fibrillation. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 159:146-156. [PMID: 33011190 DOI: 10.1016/j.pbiomolbio.2020.09.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 09/17/2020] [Accepted: 09/27/2020] [Indexed: 12/29/2022]
Abstract
Atrial fibrillation (AF) is a multifactorial disease, which often occurs in the presence of underlying cardiac abnormalities and is supported by electrophysiological and structural alterations, generally referred to as atrial remodeling. Abnormal substrates are commonly encountered in various conditions that predispose to AF, such as hypertension, heart failure, obesity, and sleep apnea, in which atrial stretch plays a key mechanistic role. Emerging evidence suggests a role for microRNAs (small non-coding RNAs) in the pathogenesis of AF, where they can act as post-transcriptional regulators of the genes involved in atrial remodeling. This review summarizes the experimental and clinical evidence that supports the role of microRNAs in the modulation of atrial electrical and structural remodeling with a focus on overload-induced atrial alterations, and discusses the potential contribution of microRNAs to mechano-electrical coupling and AF.
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Affiliation(s)
- Flavia Ravelli
- Laboratory of Biophysics and Biosignals, University of Trento, Trento, Italy.
| | - Michela Masè
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy; Healthcare Research and Innovation Program, IRCS-HTA, Bruno Kessler Foundation, Trento, Italy
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19
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Ng FS, Handa BS, Li X, Peters NS. Toward Mechanism-Directed Electrophenotype-Based Treatments for Atrial Fibrillation. Front Physiol 2020; 11:987. [PMID: 33013435 PMCID: PMC7493660 DOI: 10.3389/fphys.2020.00987] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 07/20/2020] [Indexed: 12/19/2022] Open
Abstract
Current treatment approaches for persistent atrial fibrillation (AF) have a ceiling of success of around 50%. This is despite 15 years of developing adjunctive ablation strategies in addition to pulmonary vein isolation to target the underlying arrhythmogenic substrate in AF. A major shortcoming of our current approach to AF treatment is its predominantly empirical nature. This has in part been due to a lack of consensus on the mechanisms that sustain human AF. In this article, we review evidence suggesting that the previous debates on AF being either an organized arrhythmia with a focal driver or a disorganized rhythm sustained by multiple wavelets, may prove to be a false dichotomy. Instead, a range of fibrillation electrophenotypes exists along a continuous spectrum, and the predominant mechanism in an individual case is determined by the nature and extent of remodeling of the underlying substrate. We propose moving beyond the current empirical approach to AF treatment, highlight the need to prescribe AF treatments based on the underlying AF electrophenotype, and review several possible novel mapping algorithms that may be useful in discerning the AF electrophenotype to guide tailored treatments, including Granger Causality mapping.
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Affiliation(s)
- Fu Siong Ng
- National Heart & Lung Institute, Imperial College London, London, United Kingdom
| | - Balvinder S Handa
- National Heart & Lung Institute, Imperial College London, London, United Kingdom
| | - Xinyang Li
- National Heart & Lung Institute, Imperial College London, London, United Kingdom
| | - Nicholas S Peters
- National Heart & Lung Institute, Imperial College London, London, United Kingdom
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20
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Lu Y, Chen Y, Lin Y, Chen S, Chen Y. Mechanoelectrical feedback in pulmonary vein arrhythmogenesis: Clinical challenges and therapeutic opportunities. J Arrhythm 2020; 36:608-614. [PMID: 32782628 PMCID: PMC7411213 DOI: 10.1002/joa3.12391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 05/28/2020] [Accepted: 06/04/2020] [Indexed: 12/24/2022] Open
Abstract
Mechanoelectrical feedback is an important factor in the pathophysiology of atrial fibrillation (AF). Ectopic electrical activity originating from pulmonary vein (PV) myocardial sleeves has been found to trigger and maintain paroxysmal AF. Dilated PVs by high stretching force may activate mechanoelectrical feedback, which induces calcium overload and produces afterdepolarization. These results, in turn, increase PV arrhythmogenesis and contribute to initiation of AF. Paracrine factors, effectors of the renin-angiotensin system, membranous channels, or cytoskeleton of PV myocytes may modulate PV arrhythmogenesis directly through mechanoelectrical feedback or indirectly through endocardial/myocardial cross-talk. The purpose of this review is to present laboratory and translational relevance of mechanoelectrical feedback in PV arrhythmogenesis. Targeting mechanoelectrical feedback in PV arrhythmogenesis may shed light on potential opportunities and clinical concerns of AF treatment.
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Affiliation(s)
- Yen‐Yu Lu
- Division of CardiologyDepartment of Internal MedicineSijhih Cathay General HospitalNew Taipei CityTaiwan
- School of MedicineFu‐Jen Catholic UniversityNew Taipei CityTaiwan
| | - Yao‐Chang Chen
- Department of Biomedical Engineering and Institute of PhysiologyNational Defense Medical CenterTaipeiTaiwan
| | - Yung‐Kuo Lin
- Division of Cardiovascular MedicineDepartment of Internal MedicineWan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
- Cardiovacular Research CenterWan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
| | - Shih‐Ann Chen
- Heart Rhythm Center and Division of CardiologyDepartment of MedicineTaipei Veterans General HospitalTaipeiTaiwan
| | - Yi‐Jen Chen
- Division of Cardiovascular MedicineDepartment of Internal MedicineWan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
- Cardiovacular Research CenterWan Fang HospitalTaipei Medical UniversityTaipeiTaiwan
- Graduate Institute of Clinical MedicineCollege of MedicineTaipei Medical UniversityTaipeiTaiwan
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21
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Serum N-Acetylneuraminic Acid Is Associated with Atrial Fibrillation and Left Atrial Enlargement. Cardiol Res Pract 2020; 2020:1358098. [PMID: 32351730 PMCID: PMC7174944 DOI: 10.1155/2020/1358098] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 03/12/2020] [Accepted: 03/19/2020] [Indexed: 11/29/2022] Open
Abstract
Purpose Recent studies have indicated that N-acetylneuraminic acid (Neu5Ac) plays a key role in severe coronary artery diseases, involving RhoA signaling pathway activation, which is critically involved in cardiac fibrosis. There is convincing evidence from many studies that left atrium fibrosis is involved in the pathophysiology of AF. Therefore, we speculated that Neu5Ac may be associated with atrial fibrillation (AF) and involved in the development of AF. This study aims to investigate the clinical relationship between Neu5Ac and AF and left atrial enlargement. Methods Forty-five patients with AF (AF group) and forty-five patients with non-AF (control group) matched for age, sex, and hospitalization date were recruited for our study. Plasma concentrations of Neu5Ac from peripheral venous blood were analyzed using enzyme-linked immunosorbent assay (ELISA). The baseline characteristics, plasma level of Neu5Ac, and echocardiographic characteristics were evaluated. Results The plasma level of Neu5Ac was significantly higher in the AF group than in the control group (107.66 ± 47.50 vs 77.87 ± 39.09 ng/ml; P < 0.05); the left atrial diameters were positively correlated with the plasma Neu5Ac level (R = 0.255; P < 0.05). The plasma Neu5Ac level (R = 0.368; P < 0.05) and the left atrial diameters (R = 0.402; P < 0.05) were positively correlated with AF history times. Neu5Ac (odds ratio 1.018, 95% CI 1.003–1.032; P < 0.05) and the left atrial diameter (odds ratio 1.142, 95% CI 1.020–1.280; P < 0.05) were independent risk factors for AF in multivariate regression analysis. Conclusions Serum Neu5Ac is associated with atrial fibrillation, and the mechanism may involve left atrial enlargement.
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22
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Darlington A, McCauley MD. Atrial Cardiomyopathy: An Unexplored Limb of Virchow's Triad for AF Stroke Prophylaxis. Front Cardiovasc Med 2020; 7:11. [PMID: 32133372 PMCID: PMC7039862 DOI: 10.3389/fcvm.2020.00011] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 01/27/2020] [Indexed: 01/14/2023] Open
Abstract
The most dreaded complication of atrial fibrillation is stroke, and 70–80% of patients with AF-related stroke die or become disabled. The mechanisms of thromboembolism in AF are multifactorial, with evidence demonstrating that all three criteria of Virchow's triad are satisfied in AF: abnormal stasis of blood, endothelial damage, and hypercoagulability. Mechanistic insights into the latter two limbs have resulted in effective stroke prophylactic therapies (left atrial appendage occlusion and oral anticoagulants); however, despite these advances, there remains an excess of stroke in the AF population that may be due, in part, to a lack of mechanistic understanding of atrial hypocontractility resulting in abnormal stasis of blood within the atrium. These observations support the emerging concept of atrial cardiomyopathy as a cause of stroke. In this Review, we evaluate molecular, translational, and clinical evidence for atrial cardiomyopathy as a cause for stroke from AF, and present a rationale for further investigation of this largely unaddressed limb of Virchow's triad in AF.
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Affiliation(s)
- Ashley Darlington
- Division of Cardiology, Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States.,Jesse Brown VA Medical Center, Chicago, IL, United States
| | - Mark D McCauley
- Division of Cardiology, Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States.,Jesse Brown VA Medical Center, Chicago, IL, United States.,Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, United States
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23
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Ma Z, Zhang K, Wang Y, Wang W, Yang Y, Liang X, Zhang Y, Li G. Doxycycline Improves Fibrosis-Induced Abnormalities in Atrial Conduction and Vulnerability to Atrial Fibrillation in Chronic Intermittent Hypoxia Rats. Med Sci Monit 2020; 26:e918883. [PMID: 31974331 PMCID: PMC6998791 DOI: 10.12659/msm.918883] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Background The structural remodeling of atrial architecture, especially increased amounts of fibrosis, is a critical substrate to atrial fibrillation (AF). Doxycycline (Doxy) has recently been shown to exert protective effects against fibrogenic response. This study investigated whether doxycycline (Doxy) can sufficiently ameliorate the fibrosis-induced changes of atrial conduction and AF vulnerability in a chronic intermittent hypoxia (CIH) rat model. Material/Methods Sixty rats were randomized into 3 groups: Control, CIH, and CIH with Doxy treatment (DOXY) group. CIH rats were exposed to CIH (6 h/d) and Doxy-treated rats were treated with Doxy during processing CIH. After 6 weeks, echocardiographic and hemodynamic parameters were measured. Isolated atrial epicardial activation mapping and heart electrophysiology were performed. The extent of atrial interstitial fibrosis were estimated by Masson’s trichrome staining. The expression levels of TGF-β1 and downstream factors were determined by real-Time PCR, immunohistochemistry, and Western blot analysis. Results Compared to Control rats, the CIH rats showed significant atrial interstitial fibrosis, longer inter-atrial conduction time, and elevated conduction inhomogeneity and AF inducibility, and the expression of TGF-β1, TGF-βRI, TGF-βRII, P-Smad2/3, α-SMA, CTGF, and Collagen I were significantly increased, whereas the velocity of atrial conduction and the expression of miR-30c were dramatically decreased. All of these changes were significantly improved by Doxy treatment. Conclusions The findings suggested that Doxy can profoundly mitigate atrial fibrosis, conduction inhomogeneity as well as high AF inducibility secondary to fibrosis in a CIH rat model through suppressing the TGF-β1 signaling pathway.
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Affiliation(s)
- Zuowang Ma
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China (mainland)
| | - Kai Zhang
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China (mainland)
| | - Yun Wang
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China (mainland)
| | - Weiding Wang
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China (mainland)
| | - Yu Yang
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China (mainland)
| | - Xue Liang
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China (mainland)
| | - Yue Zhang
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China (mainland)
| | - Guangping Li
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China (mainland)
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Abstract
The authors discuss the concept of atrial myopathy; its relationship to aging, electrophysiological remodeling, and autonomic remodeling; the interplay between atrial myopathy, AF, and stroke; and suggest how to identify patients with atrial myopathy and how to incorporate atrial myopathy into decisions about anticoagulation. Atrial myopathy seen in animal models of AF and in patients with AF is the result of a combination of factors that lead to electrical and structural remodeling in the atrium. Although AF may lead to the initiation and/or progression of this myopathy, the presence of AF is by no means essential to the development or the maintenance of the atrial myopathic state. Methods to identify atrial myopathy include atrial electrograms, tissue biopsy, cardiac imaging, and certain serum biomarkers. A promising modality is 4-dimensional flow cardiac magnetic resonance. The concept of atrial myopathy may help guide oral anticoagulant therapy in selected groups of patients with AF, particularly those with low to intermediate risk of strokes and those who have undergone successful AF ablation. This review highlights the need for prospective randomized trials to test these hypotheses.
This paper discusses the evolving concept of atrial myopathy by presenting how it develops and how it affects the properties of the atria. It also reviews the complex relationships among atrial myopathy, atrial fibrillation (AF), and stroke. Finally, it discusses how to apply the concept of atrial myopathy in the clinical setting—to identify patients with atrial myopathy and to be more selective in anticoagulation in a subset of patients with AF. An apparent lack of a temporal relationship between episodes of paroxysmal AF and stroke in patients with cardiac implantable electronic devices has led investigators to search for additional factors that are responsible for AF-related strokes. Multiple animal models and human studies have revealed a close interplay of atrial myopathy, AF, and stroke via various mechanisms (e.g., aging, inflammation, oxidative stress, and stretch), which, in turn, lead to fibrosis, electrical and autonomic remodeling, and a pro-thrombotic state. The complex interplay among these mechanisms creates a vicious cycle of ever-worsening atrial myopathy and a higher risk of more sustained AF and strokes. By highlighting the importance of atrial myopathy and the risk of strokes independent of AF, this paper reviews the methods to identify patients with atrial myopathy and proposes a way to incorporate the concept of atrial myopathy to guide anticoagulation in patients with AF.
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Key Words
- 4D, 4 dimensional
- AF, atrial fibrillation
- APD, action potential duration
- CMR, cardiac magnetic resonance
- CRP, C-reactive protein
- Ca2+, calcium
- Cx, connexin
- GDF, growth differentiation factor
- IL, interleukin
- K+, potassium
- LA, left atrial
- LAA, left atrial appendage
- NADPH, nicotinamide adenine dinucleotide phosphate
- NOX2, catalytic, membrane-bound subunit of NADPH oxidase
- NT-proBNP, N-terminal pro B-type natriuretic peptide
- OAC, oral anticoagulant
- ROS, reactive oxygen species
- TGF, transforming growth factor
- TNF, tumor necrosis factor
- atrial fibrillation
- atrial myopathy
- electrophysiology
- thrombosis
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Affiliation(s)
- Mark J Shen
- Feinberg Cardiovascular and Renal Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.,Cardiac Electrophysiology, Prairie Heart Institute of Illinois, HSHS St. John's Hospital, Springfield, Illinois
| | - Rishi Arora
- Feinberg Cardiovascular and Renal Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - José Jalife
- Center for Arrhythmia Research, University of Michigan, Ann Arbor, Michigan.,Centro Nacional de Investigaciones Cardiovasculares, Carlos III (CNIC), and CIBERCV, Madrid, Spain
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25
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Gharaviri A, Verheule S, Eckstein J, Potse M, Krause R, Auricchio A, Kuijpers NHL, Schotten U. Effect of Na+-channel blockade on the three-dimensional substrate of atrial fibrillation in a model of endo-epicardial dissociation and transmural conduction. Europace 2019; 20:iii69-iii76. [PMID: 30476060 DOI: 10.1093/europace/euy236] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 10/15/2018] [Indexed: 11/14/2022] Open
Abstract
Aims Atrial fibrillation (AF) is a progressive arrhythmia characterized by structural alterations that increase its stability. Both clinical and experimental studies showed a concomitant loss of antiarrhythmic drug efficacy in later stages of AF. The mechanisms underlying this loss of efficacy are not well understood. We hypothesized that structural remodelling may explain this reduced efficacy by making the substrate more three-dimensional. To investigate this, we simulated the effect of sodium (Na+)-channel block on AF in a model of progressive transmural uncoupling. Methods and results In a computer model consisting of two cross-connected atrial layers, with realistic atrial membrane behaviour, structural remodelling was simulated by reducing the number of connections between the layers. 100% of endo-epicardial connectivity represented a healthy atrium. At various degrees of structural remodelling, we assessed the effect of 60% sodium channel block on AF stability, endo-epicardial electrical activity dissociation (EED), and fibrillatory conduction pattern complexity quantified by number of waves, phase singularities (PSs), and transmural conduction ('breakthrough', BT). Sodium channel block terminated AF in non-remodelled but not in remodelled atria. The temporal excitable gap (EG) and AF cycle length increased at all degrees of remodelling when compared with control. Despite an increase of EED and EG, sodium channel block decreased the incidence of BT because of transmural conduction block. Sodium channel block decreased the number of waves and PSs in normal atrium but not in structurally remodelled atrium. Conclusion This simple atrial model explains the loss of efficacy of sodium channel blockers in terminating AF in the presence of severe structural remodelling as has been observed experimentally and clinically. Atrial fibrillation termination in atria with moderate structural remodelling in the presence of sodium channel block is caused by reduction of AF complexity. With more severe structural remodelling, sodium channel block fails to promote synchronization of the two layers of the model.
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Affiliation(s)
- Ali Gharaviri
- Department of Physiology, Maastricht University, Universiteitssingel 50, ER, Maastricht, The Netherlands.,Center for Computational Medicine in Cardiology, Institute of Computational Science, Università della Svizzera italiana, Lugano, Switzerland
| | - Sander Verheule
- Department of Physiology, Maastricht University, Universiteitssingel 50, ER, Maastricht, The Netherlands
| | - Jens Eckstein
- Department of Physiology, Maastricht University, Universiteitssingel 50, ER, Maastricht, The Netherlands.,Department of Internal Medicine, University Hospital Basel, Basel, Switzerland
| | - Mark Potse
- Carmen Team, Inria Bordeaux Sud-Ouest, Talence, France.,Université de Bordeaux, IMB, Talence F-33400, France.,IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
| | - Rolf Krause
- Center for Computational Medicine in Cardiology, Institute of Computational Science, Università della Svizzera italiana, Lugano, Switzerland
| | - Angelo Auricchio
- Center for Computational Medicine in Cardiology, Institute of Computational Science, Università della Svizzera italiana, Lugano, Switzerland.,Fondazione Cardiocentro Ticino, Lugano, Switzerland
| | - Nico H L Kuijpers
- Department of Biomedical Engineering, Maastricht University, Maastricht, The Netherlands
| | - Ulrich Schotten
- Department of Physiology, Maastricht University, Universiteitssingel 50, ER, Maastricht, The Netherlands
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26
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Essayagh B, Antoine C, Benfari G, Messika-Zeitoun D, Michelena H, Le Tourneau T, Mankad S, Tribouilloy CM, Thapa P, Enriquez-Sarano M. Prognostic Implications of Left Atrial Enlargement in Degenerative Mitral Regurgitation. J Am Coll Cardiol 2019; 74:858-870. [DOI: 10.1016/j.jacc.2019.06.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/08/2019] [Accepted: 06/03/2019] [Indexed: 01/07/2023]
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27
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Sugumar H, Nanayakkara S, Prabhu S, Voskoboinik A, Kaye DM, Ling LH, Kistler PM. Pathophysiology of Atrial Fibrillation and Heart Failure. Cardiol Clin 2019; 37:131-138. [DOI: 10.1016/j.ccl.2019.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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28
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Ni H, Zhang H, Grandi E, Narayan SM, Giles WR. Transient outward K + current can strongly modulate action potential duration and initiate alternans in the human atrium. Am J Physiol Heart Circ Physiol 2018; 316:H527-H542. [PMID: 30576220 DOI: 10.1152/ajpheart.00251.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Efforts to identify the mechanisms for the initiation and maintenance of human atrial fibrillation (AF) often focus on changes in specific elements of the atrial "substrate," i.e., its electrophysiological properties and/or structural components. We used experimentally validated mathematical models of the human atrial myocyte action potential (AP), both at baseline in sinus rhythm (SR) and in the setting of chronic AF, to identify significant contributions of the Ca2+-independent transient outward K+ current ( Ito) to electrophysiological instability and arrhythmia initiation. First, we explored whether changes in the recovery or restitution of the AP duration (APD) and/or its dynamic stability (alternans) can be modulated by Ito. Recent reports have identified disease-dependent spatial differences in expression levels of the specific K+ channel α-subunits that underlie Ito in the left atrium. Therefore, we studied the functional consequences of this by deletion of 50% of native Ito (Kv4.3) and its replacement with Kv1.4. Interestingly, significant changes in the short-term stability of the human atrial AP waveform were revealed. Specifically, this K+ channel isoform switch produced discontinuities in the initial slope of the APD restitution curve and appearance of APD alternans. This pattern of in silico results resembles some of the changes observed in high-resolution clinical electrophysiological recordings. Important insights into mechanisms for these changes emerged from known biophysical properties (reactivation kinetics) of Kv1.4 versus those of Kv4.3. These results suggest new approaches for pharmacological management of AF, based on molecular properties of specific K+ isoforms and their changed expression during progressive disease. NEW & NOTEWORTHY Clinical studies identify oscillations (alternans) in action potential (AP) duration as a predictor for atrial fibrillation (AF). The abbreviated AP in AF also involves changes in K+ currents and early repolarization of the AP. Our simulations illustrate how substitution of Kv1.4 for the native current, Kv4.3, alters the AP waveform and enhances alternans. Knowledge of this "isoform switch" and related dynamics in the AF substrate may guide new approaches for detection and management of AF.
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Affiliation(s)
- Haibo Ni
- Biological Physics Group, School of Physics and Astronomy, University of Manchester , Manchester , United Kingdom.,Department of Pharmacology, University of California , Davis, California
| | - Henggui Zhang
- Biological Physics Group, School of Physics and Astronomy, University of Manchester , Manchester , United Kingdom
| | - Eleonora Grandi
- Department of Pharmacology, University of California , Davis, California
| | - Sanjiv M Narayan
- Division of Cardiology, Cardiovascular Institute, Stanford University , Stanford, California
| | - Wayne R Giles
- Faculties of Kinesiology and Medicine, University of Calgary , Calgary, Alberta , Canada
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29
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Irakoze É, Jacquemet V. Simulated P wave morphology in the presence of endo-epicardial activation delay. Europace 2018; 20:iii16-iii25. [PMID: 30476058 DOI: 10.1093/europace/euy229] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 09/18/2018] [Indexed: 11/14/2022] Open
Abstract
Aims Evidences of asynchrony between epicardial and endocardial activation in the atrial wall have been reported. We used a computer model of the atria and torso to investigate the consequences of such activation delay on P wave morphology, while controlling for P wave duration. Methods and results We created 390 models of the atria based on the same geometry. These models differed by atrial wall thickness (from 2 to 3 mm), transmural coupling, and tissue conductivity in the endocardial and epicardial layers. Among them, 18 were in baseline, 186 had slower conduction in the epicardium layer and 186 in the endocardial layer. Conduction properties were adjusted in such a way that total activation time was the same in all models. P waves on a 16-lead system were simulated during sinus rhythm. Activation maps were similar in all cases. Endo-epicardial delay varied between -5.5 and 5.5 ms vs. 0 ± 0.5 ms in baseline. All P waves had the same duration but variability in their morphology was observed. With slower epicardial conduction, P wave amplitude was reduced by an average of 20% on leads V3-V5 and P wave area decreased by 50% on leads V1-V2 and by 40% on lead V3. Reversed, lower magnitude effects were observed with slower endocardial conduction. Conclusion An endo-epicardial delay of a few milliseconds is sufficient to significantly alter P wave morphology, even if the activation map remains the same.
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Affiliation(s)
- Éric Irakoze
- Département de Pharmacologie et Physiologie, Institut de Génie Biomédical, Université de Montréal, Montréal, QC, Canada
- Centre de Recherche, Hôpital du Sacré-Cœur de Montréal, 5400 boul. Gouin Ouest, Montréal, QC, Canada
| | - Vincent Jacquemet
- Département de Pharmacologie et Physiologie, Institut de Génie Biomédical, Université de Montréal, Montréal, QC, Canada
- Centre de Recherche, Hôpital du Sacré-Cœur de Montréal, 5400 boul. Gouin Ouest, Montréal, QC, Canada
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30
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Denham NC, Pearman CM, Caldwell JL, Madders GWP, Eisner DA, Trafford AW, Dibb KM. Calcium in the Pathophysiology of Atrial Fibrillation and Heart Failure. Front Physiol 2018; 9:1380. [PMID: 30337881 PMCID: PMC6180171 DOI: 10.3389/fphys.2018.01380] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 09/11/2018] [Indexed: 12/20/2022] Open
Abstract
Atrial fibrillation (AF) is commonly associated with heart failure. A bidirectional relationship exists between the two-AF exacerbates heart failure causing a significant increase in heart failure symptoms, admissions to hospital and cardiovascular death, while pathological remodeling of the atria as a result of heart failure increases the risk of AF. A comprehensive understanding of the pathophysiology of AF is essential if we are to break this vicious circle. In this review, the latest evidence will be presented showing a fundamental role for calcium in both the induction and maintenance of AF. After outlining atrial electrophysiology and calcium handling, the role of calcium-dependent afterdepolarizations and atrial repolarization alternans in triggering AF will be considered. The atrial response to rapid stimulation will be discussed, including the short-term protection from calcium overload in the form of calcium signaling silencing and the eventual progression to diastolic calcium leak causing afterdepolarizations and the development of an electrical substrate that perpetuates AF. The role of calcium in the bidirectional relationship between heart failure and AF will then be covered. The effects of heart failure on atrial calcium handling that promote AF will be reviewed, including effects on both atrial myocytes and the pulmonary veins, before the aspects of AF which exacerbate heart failure are discussed. Finally, the limitations of human and animal studies will be explored allowing contextualization of what are sometimes discordant results.
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Affiliation(s)
- Nathan C. Denham
- Unit of Cardiac Physiology, Division of Cardiovascular Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | | | | | | | | | | | - Katharine M. Dibb
- Unit of Cardiac Physiology, Division of Cardiovascular Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
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31
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Ramdjan TT, Mouws EM, Teuwen CP, Sitorus GD, Houck CA, Bogers AJ, de Groot NM. Progression of late postoperative atrial fibrillation in patients with tetralogy of Fallot. J Cardiovasc Electrophysiol 2017; 29:30-37. [DOI: 10.1111/jce.13369] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 08/31/2017] [Accepted: 09/18/2017] [Indexed: 11/29/2022]
Affiliation(s)
| | - Elisabeth M.J.P. Mouws
- Department of Cardiology; Erasmus University Medical Center; Rotterdam The Netherlands
- Department of Cardiothoracic Surgery; Erasmus University Medical Center; Rotterdam The Netherlands
| | - Christophe P. Teuwen
- Department of Cardiology; Erasmus University Medical Center; Rotterdam The Netherlands
| | - Gustaf D.S. Sitorus
- Department of Cardiology; Erasmus University Medical Center; Rotterdam The Netherlands
| | - Charlotte A. Houck
- Department of Cardiology; Erasmus University Medical Center; Rotterdam The Netherlands
| | - Ad J.J.C. Bogers
- Department of Cardiothoracic Surgery; Erasmus University Medical Center; Rotterdam The Netherlands
| | - Natasja M.S. de Groot
- Department of Cardiology; Erasmus University Medical Center; Rotterdam The Netherlands
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32
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Schönleitner P, Schotten U, Antoons G. Mechanosensitivity of microdomain calcium signalling in the heart. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2017. [PMID: 28648626 DOI: 10.1016/j.pbiomolbio.2017.06.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In cardiac myocytes, calcium (Ca2+) signalling is tightly controlled in dedicated microdomains. At the dyad, i.e. the narrow cleft between t-tubules and junctional sarcoplasmic reticulum (SR), many signalling pathways combine to control Ca2+-induced Ca2+ release during contraction. Local Ca2+ gradients also exist in regions where SR and mitochondria are in close contact to regulate energetic demands. Loss of microdomain structures, or dysregulation of local Ca2+ fluxes in cardiac disease, is often associated with oxidative stress, contractile dysfunction and arrhythmias. Ca2+ signalling at these microdomains is highly mechanosensitive. Recent work has demonstrated that increasing mechanical load triggers rapid local Ca2+ releases that are not reflected by changes in global Ca2+. Key mechanisms involve rapid mechanotransduction with reactive oxygen species or nitric oxide as primary signalling molecules targeting SR or mitochondria microdomains depending on the nature of the mechanical stimulus. This review summarizes the most recent insights in rapid Ca2+ microdomain mechanosensitivity and re-evaluates its (patho)physiological significance in the context of historical data on the macroscopic role of Ca2+ in acute force adaptation and mechanically-induced arrhythmias. We distinguish between preload and afterload mediated effects on local Ca2+ release, and highlight differences between atrial and ventricular myocytes. Finally, we provide an outlook for further investigation in chronic models of abnormal mechanics (eg post-myocardial infarction, atrial fibrillation), to identify the clinical significance of disturbed Ca2+ mechanosensitivity for arrhythmogenesis.
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Affiliation(s)
- Patrick Schönleitner
- Dept of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands
| | - Uli Schotten
- Dept of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands
| | - Gudrun Antoons
- Dept of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands.
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33
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Matějková A, Šteiner I. Association of Atrial Fibrillation with Morphological and Electrophysiological Changes of the Atrial Myocardium. ACTA MEDICA (HRADEC KRÁLOVÉ) 2017; 59:43-9. [PMID: 27526304 DOI: 10.14712/18059694.2016.88] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. For long time it was considered as pure functional disorder, but in recent years, there were identified atrial locations, which are involved in the initiation and maintenance of this arrhythmia. These structural changes, so called remodelation, start at electric level and later they affect contractility and morphology. In this study we attempted to find a possible relation between morphological (scarring, amyloidosis, left atrial (LA) enlargement) and electrophysiological (ECG features) changes in patients with AF. We examined grossly and histologically 100 hearts of necropsy patients - 54 with a history of AF and 46 without AF. Premortem ECGs were evaluated. The patients with AF had significantly heavier heart, larger LA, more severely scarred myocardium of the LA and atrial septum, and more severe amyloidosis in both atria. Severity of amyloidosis was higher in LAs vs. right atria (RAs). Distribution of both fibrosis and amyloidosis was irregular. The most affected area was in the LA anterior wall. Patients with a history of AF and with most severe amyloidosis have more often abnormally long P waves. Finding of long P wave may contribute to diagnosis of a hitherto undisclosed atrial fibrillation.
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Affiliation(s)
- Adéla Matějková
- Charles University, Faculty of Medicine and University Hospital in Hradec Králové, Fingerland Department of Pathology, Hradec Králové, Czech Republic.
| | - Ivo Šteiner
- Charles University, Faculty of Medicine and University Hospital in Hradec Králové, Fingerland Department of Pathology, Hradec Králové, Czech Republic
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34
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Abstract
Cardiac arrhythmias can follow disruption of the normal cellular electrophysiological processes underlying excitable activity and their tissue propagation as coherent wavefronts from the primary sinoatrial node pacemaker, through the atria, conducting structures and ventricular myocardium. These physiological events are driven by interacting, voltage-dependent, processes of activation, inactivation, and recovery in the ion channels present in cardiomyocyte membranes. Generation and conduction of these events are further modulated by intracellular Ca2+ homeostasis, and metabolic and structural change. This review describes experimental studies on murine models for known clinical arrhythmic conditions in which these mechanisms were modified by genetic, physiological, or pharmacological manipulation. These exemplars yielded molecular, physiological, and structural phenotypes often directly translatable to their corresponding clinical conditions, which could be investigated at the molecular, cellular, tissue, organ, and whole animal levels. Arrhythmogenesis could be explored during normal pacing activity, regular stimulation, following imposed extra-stimuli, or during progressively incremented steady pacing frequencies. Arrhythmic substrate was identified with temporal and spatial functional heterogeneities predisposing to reentrant excitation phenomena. These could arise from abnormalities in cardiac pacing function, tissue electrical connectivity, and cellular excitation and recovery. Triggering events during or following recovery from action potential excitation could thereby lead to sustained arrhythmia. These surface membrane processes were modified by alterations in cellular Ca2+ homeostasis and energetics, as well as cellular and tissue structural change. Study of murine systems thus offers major insights into both our understanding of normal cardiac activity and its propagation, and their relationship to mechanisms generating clinical arrhythmias.
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Affiliation(s)
- Christopher L-H Huang
- Physiological Laboratory and the Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
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35
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Baker WL, Coleman CI. Meta-analysis of ascorbic acid for prevention of postoperative atrial fibrillation after cardiac surgery. Am J Health Syst Pharm 2016; 73:2056-2066. [DOI: 10.2146/ajhp160066] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Affiliation(s)
- William L. Baker
- Department of Pharmacy Practice, School of Pharmacy, University of Connecticut, Storrs, CT
| | - Craig I. Coleman
- Department of Pharmacy Practice, School of Pharmacy, University of Connecticut, Storrs, CT
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36
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Stavrakis S, Dyer JW, Koomson E, Scherlag BJ, Bhardwaj B, Lazzara R, Po SS. Spectral Analysis of Baseline Electrocardiogram During Atrial Fibrillation Predicts Response to Antiarrhythmic Drug Therapy in Patients With Persistent Atrial Fibrillation. J Cardiovasc Electrophysiol 2016; 27:1312-1318. [PMID: 27506321 DOI: 10.1111/jce.13064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/28/2016] [Accepted: 08/02/2016] [Indexed: 11/27/2022]
Abstract
BACKGROUND We evaluated the ability of spectral analysis of the baseline ECG during atrial fibrillation (AF) to predict the response of persistent AF to antiarrhythmic drug therapy. METHODS Patients with persistent AF who were admitted for dofetilide loading were prospectively enrolled in the study. Atrial activity was extracted from the ECG using an Independent Component Analysis method and then subjected to a Modified Periodogram. The regularity index was computed as the ratio of the power in the dominant frequency and all its harmonics to the total power in the spectrum. Patients were followed at 1 month, 3 months and every 3 months thereafter. RESULTS Of 28 patients enrolled in the study, 14 (50%) converted acutely to sinus rhythm during the 3-day hospital loading period. The clinical and echocardiographic characteristics of patients with and without acute pharmacologic conversion were similar. The regularity index was significantly higher in those who converted to sinus rhythm compared to those who did not (0.71 ± 0.20 vs. 0.38 ± 0.13, respectively; P < 0.0001). A regularity index ≥0.44 had a 79% sensitivity and 93% specificity to predict acute conversion and was associated with a nearly 5-fold increase in the acute conversion rate (odds ratio = 4.89; 95% confidence interval 1.74-13.75; P = 0.003). The regularity index was the only independent predictor of acute conversion. Neither acute conversion, nor the regularity index predicted sinus rhythm maintenance, after a median follow-up of 10 months. CONCLUSION Increased regularity index predicts acute conversion of persistent AF during dofetilide loading, but does not predict long-term sinus rhythm maintenance.
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Affiliation(s)
- Stavros Stavrakis
- Department of Medicine and Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - John W Dyer
- Department of Medicine and Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Edward Koomson
- Department of Medicine and Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Benjamin J Scherlag
- Department of Medicine and Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Bhaskar Bhardwaj
- Department of Medicine and Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Ralph Lazzara
- Department of Medicine and Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Sunny S Po
- Department of Medicine and Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
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Lee JM, Lee H, Janardhan AH, Park J, Joung B, Pak HN, Lee MH, Kim SS, Hwang HJ. Prolonged atrial refractoriness predicts the onset of atrial fibrillation: A 12-year follow-up study. Heart Rhythm 2016; 13:1575-80. [DOI: 10.1016/j.hrthm.2016.03.037] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Indexed: 11/27/2022]
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Weiss JN, Qu Z, Shivkumar K. Ablating atrial fibrillation: A translational science perspective for clinicians. Heart Rhythm 2016; 13:1868-77. [PMID: 27241354 DOI: 10.1016/j.hrthm.2016.05.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Indexed: 12/22/2022]
Abstract
Although considerable progress has been made in developing ablation approaches to cure atrial fibrillation (AF), outcomes are still suboptimal, especially for persistent and long-lasting persistent AF. In this topical review, we review the arrhythmia mechanisms, both reentrant and nonreentrant, that are potentially relevant to human AF at various stages/settings. We describe arrhythmia mapping techniques used to distinguish between the different mechanisms, with a particular focus on the detection of rotors. We discuss which arrhythmia mechanisms are likely to respond to ablation, and the challenges and prospects for improving upon current ablation strategies to achieve better outcomes.
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Affiliation(s)
| | - Zhilin Qu
- UCLA Cardiovascular Research Laboratory
| | - Kalyanam Shivkumar
- Cardiac Arrhythmia Center & Neurocardiology Research Center of Excellence, Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
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Romero J, Gianni C, Di Biase L, Natale A. Catheter Ablation for Long-Standing Persistent Atrial Fibrillation. Methodist Debakey Cardiovasc J 2016; 11:87-93. [PMID: 26306125 DOI: 10.14797/mdcj-11-2-87] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Atrial fibrillation (AF) is the most common sustained arrhythmia worldwide and represents a major burden to health care systems. Atrial fibrillation is associated with a 4- to 5-fold increased risk of thromboembolic stroke. The pulmonary veins have been identified as major sources of atrial triggers for AF. This is particularly true in patients with paroxysmal AF but not always the case for those with long-standing persistent AF (LSPAF), in which other locations for ectopic beats have been well recognized. Structures with foci triggering AF include the coronary sinus, the left atrial appendage (LAA), the superior vena cava, the crista terminalis, and the ligament of Marshall. More than 30 studies reporting results on radiofrequency ablation of LSPAF have been published to date. Most of these are observational studies with very different methodologies using different strategies. As a result, there has been remarkable variation in short- and long-term success, which suggests that the optimal ablation technique for LSPAF is still to be elucidated. In this review we discuss the different approaches to LSPAF catheter ablation, starting with pulmonary vein isolation (PVI) through ablation lines in different left atrial locations, the role of complex fractionated atrial electrograms, focal impulses and rotor modulation, autonomic modulation (ganglionated plexi), alcohol ablation, and the future of epicardial mapping and ablation for this arrhythmia. A stepwise ablation approach requires several key ablation techniques, such as meticulous PVI, linear ablation at the roof and mitral isthmus, electrogram-targeted ablation with particular attention to triggers in the coronary sinus and LAA, and discretionary right atrial ablation (superior vena cava, intercaval, or cavotricuspid isthmus lines).
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Affiliation(s)
- Jorge Romero
- Albert Einstein College of Medicine at Montefiore Hospital, Bronx, New York ; Ronald Reagan UCLA Medical Center, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Carola Gianni
- St. David's Medical Center, Austin, Texas ; University of Milan, Milan, Italy
| | - Luigi Di Biase
- Albert Einstein College of Medicine at Montefiore Hospital, Bronx, New York ; St. David's Medical Center, Austin, Texas ; University of Texas, Austin, Texas ; University of Foggia, Foggia, Italy
| | - Andrea Natale
- St. David's Medical Center, Austin, Texas ; University of Texas, Austin, Texas ; California Pacific Medical Center, San Francisco, California ; Stanford University, Palo Alto, California ; Case Western Reserve University, Cleveland, Ohio ; Scripps Clinic, San Diego, California
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Raiten JM, Ghadimi K, Augoustides JGT, Ramakrishna H, Patel PA, Weiss SJ, Gutsche JT. Atrial fibrillation after cardiac surgery: clinical update on mechanisms and prophylactic strategies. J Cardiothorac Vasc Anesth 2016; 29:806-16. [PMID: 26009291 DOI: 10.1053/j.jvca.2015.01.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Jesse M Raiten
- Cardiovascular Critical Care Section, Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Kamrouz Ghadimi
- Division of CT Anesthesiology and Critical Care Medicine, Department of Anesthesiology, School of Medicine, Duke University, Durham, NC
| | - John G T Augoustides
- Cardiovascular and Thoracic Section, Departmsent of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
| | | | - Prakash A Patel
- Cardiovascular and Thoracic Section, Departmsent of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Stuart J Weiss
- Cardiovascular and Thoracic Section, Departmsent of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Jacob T Gutsche
- Cardiovascular and Thoracic Section, Departmsent of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
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Opacic D, van Bragt KA, Nasrallah HM, Schotten U, Verheule S. Atrial metabolism and tissue perfusion as determinants of electrical and structural remodelling in atrial fibrillation. Cardiovasc Res 2016; 109:527-41. [DOI: 10.1093/cvr/cvw007] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/12/2016] [Indexed: 12/14/2022] Open
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Kirchhof P, Breithardt G, Bax J, Benninger G, Blomstrom-Lundqvist C, Boriani G, Brandes A, Brown H, Brueckmann M, Calkins H, Calvert M, Christoffels V, Crijns H, Dobrev D, Ellinor P, Fabritz L, Fetsch T, Freedman SB, Gerth A, Goette A, Guasch E, Hack G, Haegeli L, Hatem S, Haeusler KG, Heidbüchel H, Heinrich-Nols J, Hidden-Lucet F, Hindricks G, Juul-Möller S, Kääb S, Kappenberger L, Kespohl S, Kotecha D, Lane DA, Leute A, Lewalter T, Meyer R, Mont L, Münzel F, Nabauer M, Nielsen JC, Oeff M, Oldgren J, Oto A, Piccini JP, Pilmeyer A, Potpara T, Ravens U, Reinecke H, Rostock T, Rustige J, Savelieva I, Schnabel R, Schotten U, Schwichtenberg L, Sinner MF, Steinbeck G, Stoll M, Tavazzi L, Themistoclakis S, Tse HF, Van Gelder IC, Vardas PE, Varpula T, Vincent A, Werring D, Willems S, Ziegler A, Lip GY, Camm AJ. A roadmap to improve the quality of atrial fibrillation management: proceedings from the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference. Europace 2015; 18:37-50. [DOI: 10.1093/europace/euv304] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 08/13/2015] [Indexed: 12/30/2022] Open
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Teuwen CP, Ramdjan TT, Götte M, Brundel BJ, Evertz R, Vriend JW, Molhoek SG, Dorman HG, van Opstal JM, Konings TC, van der Voort P, Delacretaz E, Houck C, Yaksh A, Jansz LJ, Witsenburg M, Roos-Hesselink JW, Triedman JK, Bogers AJ, de Groot NM. Time Course of Atrial Fibrillation in Patients With Congenital Heart Defects. Circ Arrhythm Electrophysiol 2015; 8:1065-72. [DOI: 10.1161/circep.115.003272] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 07/24/2015] [Indexed: 11/16/2022]
Affiliation(s)
- Christophe P. Teuwen
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Tanwier T.T.K. Ramdjan
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Marco Götte
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Bianca J.J.M. Brundel
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Reinder Evertz
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Joris W.J. Vriend
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Sander G. Molhoek
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Henderikus G.R. Dorman
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Jurren M. van Opstal
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Thelma C. Konings
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Pepijn van der Voort
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Etienne Delacretaz
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Charlotte Houck
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Ameeta Yaksh
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Luca. J. Jansz
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Maarten Witsenburg
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Jolien W. Roos-Hesselink
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - John K. Triedman
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Ad J.J.C. Bogers
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
| | - Natasja M.S. de Groot
- From the Department of Cardiology (C.P.T., T.T.T.K.R., C.H., A.Y., L.J.J., M.W., J.W.R.-H., N.M.S.d.G.) and Department of Cardio-Thoracic Surgery (A.J.J.C.B.), Erasmus University Medical Center, Rotterdam, The Netherlands; Department of Cardiology, Haga Hospital, The Hague, The Netherlands (M.G., J.W.J.V.); Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen, The Netherlands (B.J.J.M.B.); Department of Cardiology, VU University Medical Center, Amsterdam,
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Melduni RM, Schaff HV, Bailey KR, Cha SS, Ammash NM, Seward JB, Gersh BJ. Implications of new-onset atrial fibrillation after cardiac surgery on long-term prognosis: a community-based study. Am Heart J 2015; 170:659-68. [PMID: 26386789 DOI: 10.1016/j.ahj.2015.06.015] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 06/20/2015] [Indexed: 12/20/2022]
Abstract
BACKGROUND Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery. Data are lacking on the long-term prognostic implications of POAF. We hypothesized that POAF, which reflects underlying cardiovascular pathophysiologic substrate, is a predictive marker of late AF and long-term mortality. METHODS We identified 603 Olmsted County, Minnesota, residents without prior documented history of AF who underwent coronary artery bypass graft and/or valve surgery from 2000 to 2005. Patients were monitored for first documentation of late AF or death at >30 days postoperatively. Multivariate Cox regression models were used to assess the independent association of POAF with late AF and long-term mortality. RESULTS After a mean follow-up of 8.3 ± 4.2 years, freedom from late AF was less with POAF than no POAF (57.4% vs 88.9%, P < .001). The risk of late AF was highest within the first year at 18%. Univariate analysis demonstrated that POAF was associated with significantly increased risk of late AF [hazard ratio (HR), 5.09; 95% CI, 3.65-7.22] and long-term mortality (HR, 1.79; 95% CI, 1.38-2.22). After adjustment for age, sex, and clinical and surgical risk factors, POAF remained independently associated with development of late AF (HR, 3.52; 95% CI, 2.42-5.13) but not long-term mortality (HR, 1.16; 95% CI, 0.87-1.55). Conversely, late AF was independently predictive of long-term mortality (HR, 3.25; 95% CI, 2.42-4.35). Diastolic dysfunction independently influenced the risk of late AF and long-term mortality. CONCLUSIONS Postoperative atrial fibrillation was an independent predictive marker of late AF, whereas late AF, but not POAF, was independently associated with long-term mortality. Patients who develop new-onset POAF should be considered for continuous anticoagulation at least during the first year following cardiac surgery.
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Affiliation(s)
| | | | - Kent R Bailey
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN
| | - Stephen S Cha
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN
| | - Naser M Ammash
- Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN
| | - James B Seward
- Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN
| | - Bernard J Gersh
- Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN
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Hirsh BJ, Copeland-Halperin RS, Halperin JL. Fibrotic atrial cardiomyopathy, atrial fibrillation, and thromboembolism: mechanistic links and clinical inferences. J Am Coll Cardiol 2015; 65:2239-51. [PMID: 25998669 DOI: 10.1016/j.jacc.2015.03.557] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 03/23/2015] [Accepted: 03/24/2015] [Indexed: 12/12/2022]
Abstract
The association of atrial fibrillation (AF) with ischemic stroke has long been recognized; yet, the pathogenic mechanisms underlying this relationship are incompletely understood. Clinical schemas, such as the CHA2DS2-VASc (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, stroke/transient ischemic attack, vascular disease, age 65 to 74 years, sex category) score, incompletely account for thromboembolic risk, and emerging evidence suggests that stroke can occur in patients with AF even after sinus rhythm is restored. Atrial fibrosis correlates with both the persistence and burden of AF, and gadolinium-enhanced magnetic resonance imaging is gaining utility for detection and quantification of the fibrotic substrate, but methodological challenges limit its use. Factors related to evolution of the thrombogenic fibrotic atrial cardiomyopathy support the view that AF is a marker of stroke risk regardless of whether or not the arrhythmia is sustained. Antithrombotic therapy should be guided by a comprehensive assessment of intrinsic risk rather than the presence or absence of AF at a given time.
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Ravens U, Katircioglu-Öztürk D, Wettwer E, Christ T, Dobrev D, Voigt N, Poulet C, Loose S, Simon J, Stein A, Matschke K, Knaut M, Oto E, Oto A, Güvenir HA. Application of the RIMARC algorithm to a large data set of action potentials and clinical parameters for risk prediction of atrial fibrillation. Med Biol Eng Comput 2014; 53:263-73. [PMID: 25466224 DOI: 10.1007/s11517-014-1232-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 11/16/2014] [Indexed: 12/20/2022]
Abstract
Ex vivo recorded action potentials (APs) in human right atrial tissue from patients in sinus rhythm (SR) or atrial fibrillation (AF) display a characteristic spike-and-dome or triangular shape, respectively, but variability is huge within each rhythm group. The aim of our study was to apply the machine-learning algorithm ranking instances by maximizing the area under the ROC curve (RIMARC) to a large data set of 480 APs combined with retrospectively collected general clinical parameters and to test whether the rules learned by the RIMARC algorithm can be used for accurately classifying the preoperative rhythm status. APs were included from 221 SR and 158 AF patients. During a learning phase, the RIMARC algorithm established a ranking order of 62 features by predictive value for SR or AF. The model was then challenged with an additional test set of features from 28 patients in whom rhythm status was blinded. The accuracy of the risk prediction for AF by the model was very good (0.93) when all features were used. Without the seven AP features, accuracy still reached 0.71. In conclusion, we have shown that training the machine-learning algorithm RIMARC with an experimental and clinical data set allows predicting a classification in a test data set with high accuracy. In a clinical setting, this approach may prove useful for finding hypothesis-generating associations between different parameters.
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Affiliation(s)
- Ursula Ravens
- Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany,
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Increased expression of NF-AT3 and NF-AT4 in the atria correlates with procollagen I carboxyl terminal peptide and TGF-β1 levels in serum of patients with atrial fibrillation. BMC Cardiovasc Disord 2014; 14:167. [PMID: 25422138 PMCID: PMC4251842 DOI: 10.1186/1471-2261-14-167] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 11/17/2014] [Indexed: 01/12/2023] Open
Abstract
Background Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice. Unfortunately, the precise mechanisms and sensitive serum biomarkers of atrial remodeling in AF remain unclear. The aim of this study was to determine whether the expression of the transcription factors NF-AT3 and NF-AT4 correlate with atrial structural remodeling of atrial fibrillation and serum markers for collagen I and III synthesis. Methods Right and left atrial specimens were obtained from 90 patients undergoing valve replacement surgery. The patients were divided into sinus rhythm (n = 30), paroxysmal atrial fibrillation (n = 30), and persistent atrial fibrillation (n = 30) groups. NF-AT3, NF-AT4, and collagen I and III mRNA and protein expression in atria were measured. We also tested the levels of the carboxyl-terminal peptide from pro-collagen I, the N-terminal type I procollagen propeptides, the N-terminal type III procollagen propeptides, and TGF-β1 in serum using an enzyme immunosorbent assay. Results NF-AT3 and NF-AT4 mRNA and protein expression were increased in the AF groups, especially in the left atrium. NF-AT3 and NF-AT4 expression in the right atrium was increased in the persistent atrial fibrillation group compared the sinus rhythm group with similar valvular disease. In patients with AF, the expression levels of nuclear NF-AT3 and NF-AT4 correlated with those of collagens I and III in the atria and with PICP and TGF-β1 in blood. Conclusions These data support the hypothesis that nuclear NF-AT3 and NF-AT4 participates in atrial structural remodeling, and that PICP and TGF-β1 levels may be sensitive serum biomarkers to estimate atrial structural remodeling with atrial fibrillation.
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Labarthe S, Bayer J, Coudiere Y, Henry J, Cochet H, Jais P, Vigmond E. A bilayer model of human atria: mathematical background, construction, and assessment. Europace 2014; 16 Suppl 4:iv21-iv29. [DOI: 10.1093/europace/euu256] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Verheule S, Eckstein J, Linz D, Maesen B, Bidar E, Gharaviri A, Schotten U. Role of endo-epicardial dissociation of electrical activity and transmural conduction in the development of persistent atrial fibrillation. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2014; 115:173-85. [DOI: 10.1016/j.pbiomolbio.2014.07.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 07/19/2014] [Indexed: 10/25/2022]
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Ravelli F, Masè M, Cristoforetti A, Marini M, Disertori M. The logical operator map identifies novel candidate markers for critical sites in patients with atrial fibrillation. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2014; 115:186-97. [PMID: 25077410 DOI: 10.1016/j.pbiomolbio.2014.07.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 07/17/2014] [Indexed: 11/28/2022]
Abstract
The identification of suitable markers for critical patterns during atrial fibrillation (AF) may be crucial to guide an effective ablation treatment. Single parameter maps, based on dominant frequency and complex fractionated electrograms, have been proposed as a tool for electrogram-guided ablation, however the specificity of these markers is debated. Experimental studies suggest that AF critical patterns may be identified on the basis of specific rate and organization features, where rapid organized and rapid fragmented activities characterize respectively localized sources and critical substrates. In this paper we introduce the logical operator map, a novel mapping tool for a point-by-point identification and localization of AF critical sites. Based on advanced signal and image processing techniques, the approach combines in a single map electrogram-derived rate and organization features with tomographic anatomical detail. The construction of the anatomically-detailed logical operator map is based on the time-domain estimation of atrial rate and organization in terms of cycle length and wave-similarity, the logical combination of these indexes to obtain suitable markers of critical sites, and the multimodal integration of electrophysiological and anatomical information by segmentation and registration techniques. Logical operator maps were constructed in 14 patients with persistent AF, showing the capability of the combined rate and organization markers to identify with high selectivity the subset of electrograms associated with localized sources and critical substrates. The precise anatomical localization of these critical sites revealed the confinement of rapid organized sources in the left atrium with organization and rate gradients towards the surrounding tissue, and the presence of rapid fragmented electrograms in proximity of the sources. By merging in a single map the most relevant electrophysiological and anatomical features of the AF process, the logical operator map may have significant clinical impact as a direct, comprehensive tool to understand arrhythmia mechanisms in the single patient and guide more conservative, step-wise ablation.
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Affiliation(s)
- Flavia Ravelli
- Department of Physics, University of Trento, Povo-Trento, Italy.
| | - Michela Masè
- Department of Physics, University of Trento, Povo-Trento, Italy
| | | | | | - Marcello Disertori
- Division of Cardiology, S. Chiara Hospital, Trento, Italy; Healthcare Research and Innovation Program, PAT-FBK, Trento, Italy
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