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Enriquez A, Gonzalez R, Kumareswaran R, Supple G, Scheinman M. Electrophysiological Diagnosis of Narrow and Wide Complex Tachyarrhythmias. Heart Rhythm 2024:S1547-5271(24)02552-9. [PMID: 38734227 DOI: 10.1016/j.hrthm.2024.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Revised: 05/01/2024] [Accepted: 05/03/2024] [Indexed: 05/13/2024]
Abstract
Establishing the precise mechanism of cardiac arrhythmias in the electrophysiology laboratory is one of the main requisites for a successful and safe ablation. The present article provides an organized approach to the differential diagnosis of narrow and wide complex tachycardias based on the analysis of electrical activation patterns followed by specific pacing maneuvers in each case.
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Affiliation(s)
- Andres Enriquez
- Section of Cardiac Electrophysiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
| | | | - Ramanan Kumareswaran
- Section of Cardiac Electrophysiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Gregory Supple
- Section of Cardiac Electrophysiology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Melvin Scheinman
- Division of Electrophysiology, Department of Cardiology, University of California San Francisco, San Francisco, California
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2
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Ferns SJ, Scheinman M. Adenosine sensitive left ventricular summit ventricular tachycardia in a pre-adolescent: case report. Eur Heart J Case Rep 2023; 7:ytad430. [PMID: 37727150 PMCID: PMC10506732 DOI: 10.1093/ehjcr/ytad430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 08/10/2023] [Accepted: 08/30/2023] [Indexed: 09/21/2023]
Abstract
Background Sustained forms of tachycardia especially from the left ventricular summit are rare. Adenosine sensitive outflow tachycardias, especially from the left ventricular summit, are rarer still. These arrhythmias may be exercise or stress induced as they are facilitated by catecholamines and characteristically terminate with adenosine, vagal manoeuvres, and beta-blockers. The surface 12-lead electrocardiogram can be used to localize the anatomic site of origin before catheter ablation; however, prediction of the precise origin may still be challenging due to the intimate and complex anatomy of the outflow tracts. Case summary A 12-year-old female presented to an emergency room with frequent runs of wide complex tachycardia that terminated with adenosine but would spontaneously reinitiate. After three additional temporary terminations with adenosine and because of an inability to completely eliminate tachycardia, she was started on an esmolol infusion that resulted in an abrupt termination of tachycardia. At follow-up, she reported breakthrough episodes of tachycardia with exercise, especially associated with beta-blocker non-compliance. The rest of her cardiac testing was normal apart from an anomalous right coronary artery origin from the left coronary sinus. Given the increased frequency of symptomatic palpitations and medication non-compliance, she underwent an electrophysiology study. During the study, a ventricular tachycardia was successfully mapped to an epicardial focus at the left ventricle summit and was successfully ablated. Discussion The response of this patient's ventricular tachycardia to adenosine suggests a triggered mechanism. To our knowledge, this is the first unambiguous example of left ventricular tachycardia due to cAMP-mediated triggered activity in this age group.
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Affiliation(s)
- Sunita J Ferns
- Department of Pediatrics, University of Illinois in Chicago, 420 NE Glen Oak Avenue, Suite 301, Peoria, IL 61603, USA
| | - Melvin Scheinman
- School of Medicine, University of California San Francisco, 400 Parnassus Ave, San Francisco, CA 94122, USA
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3
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Tooley JE, Marcus GM, Scheinman M. An unruly case of atrioventricular block. Heart Rhythm 2023; 20:1337-1338. [PMID: 37648362 DOI: 10.1016/j.hrthm.2022.11.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 09/01/2023]
Affiliation(s)
- James E Tooley
- Division of Cardiology, Section on Electrophysiology, University of California San Francisco, San Francisco, California
| | - Gregory M Marcus
- Division of Cardiology, Section on Electrophysiology, University of California San Francisco, San Francisco, California
| | - Melvin Scheinman
- Division of Cardiology, Section on Electrophysiology, University of California San Francisco, San Francisco, California.
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4
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Mayfield JJ, Bogomolovas J, Abraham MR, Sullivan K, Seo Y, Sheikh F, Scheinman M. Recurrent Myocarditis in Patients With Desmosomal Pathogenic Variants: Is Self Antigen Presentation the Link? JACC Clin Electrophysiol 2023; 9:2024-2033. [PMID: 37480874 DOI: 10.1016/j.jacep.2023.04.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 04/10/2023] [Accepted: 04/15/2023] [Indexed: 07/24/2023]
Abstract
Myocarditis is frequently associated with viral infections. Increasing evidence points to an association between myocarditis and inherited cardiomyopathies, though it is unclear whether myocarditis is a driver or an accessory. We present a primary vignette and case series highlighting recurrent myocarditis in patients later found to harbor pathogenic desmosomal variants and provide clinical and basic science context, exploring 2 potentially overlapping hypotheses: that stress induces cellular injury and death in structurally abnormal myocytes and that recurrent viral myocardial and truncated desomosomal protein byproducts as 2 hits could lead to loss of immune tolerance and subsequent autoreactivity.
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Affiliation(s)
- Jacob J Mayfield
- Division of Cardiology, University of Washington, Seattle, Washington, USA; Division of Cardiology, University of California-San Francisco, San Francisco, California, USA
| | - Julius Bogomolovas
- Department of Medicine, University of California-San Diego, La Jolla, California, USA
| | - M Roselle Abraham
- Division of Cardiology, University of California-San Francisco, San Francisco, California, USA; Department of Radiology, University of California-San Francisco, San Francisco, California, USA
| | - Kathryn Sullivan
- Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, University of California-San Francisco, San Francisco, California, USA
| | - Youngho Seo
- Department of Radiology, University of California-San Francisco, San Francisco, California, USA
| | - Farah Sheikh
- Department of Medicine, University of California-San Diego, La Jolla, California, USA.
| | - Melvin Scheinman
- Division of Cardiology, University of California-San Francisco, San Francisco, California, USA.
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5
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Kheiri B, Vedantham V, Scheinman M. A very wide complex tachycardia. Heart Rhythm 2023; 20:937-939. [PMID: 37245898 DOI: 10.1016/j.hrthm.2022.08.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 08/23/2022] [Indexed: 05/30/2023]
Affiliation(s)
- Babikir Kheiri
- Section of Cardiac Electrophysiology, Division of Cardiology, University of California, San Francisco, San Francisco, California
| | - Vasanth Vedantham
- Section of Cardiac Electrophysiology, Division of Cardiology, University of California, San Francisco, San Francisco, California
| | - Melvin Scheinman
- Section of Cardiac Electrophysiology, Division of Cardiology, University of California, San Francisco, San Francisco, California.
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6
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Han FT, Scheinman M. A rapid wide complex tachycardia. Heart Rhythm 2023; 20:471-472. [PMID: 36842790 DOI: 10.1016/j.hrthm.2022.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 02/28/2023]
Affiliation(s)
- Frederick T Han
- Division of Cardiovascular Medicine, University of California, San Diego, La Jolla, California.
| | - Melvin Scheinman
- Division of Cardiology, University of California, San Francisco, San Francisco, California
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7
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Sarcon A, Liem B, Scheinman M. An unusual cause of a relatively narrow, wide complex tachycardia. Heart Rhythm 2022; 19:1910-1911. [PMID: 35257977 DOI: 10.1016/j.hrthm.2022.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 03/01/2022] [Accepted: 03/01/2022] [Indexed: 11/04/2022]
Affiliation(s)
- Anna Sarcon
- Division of Cardiology, Section on Electrophysiology, University of California San Francisco, San Francisco, California
| | - Bing Liem
- Division of Cardiology, Section on Electrophysiology, University of California San Francisco, San Francisco, California
| | - Melvin Scheinman
- Division of Cardiology, Section on Electrophysiology, University of California San Francisco, San Francisco, California.
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8
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Violano M, Poller W, Abraham MR, Huemer M, Scheinman M, Landmesser U, Heidecker B. Deadly emotional argument: Sudden cardiac death in catecholaminergic polymorphic ventricular tachycardia (CPVT). IJC Heart & Vasculature 2022; 41:101062. [PMID: 35663620 PMCID: PMC9156936 DOI: 10.1016/j.ijcha.2022.101062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/01/2022] [Accepted: 05/19/2022] [Indexed: 11/25/2022]
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9
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Cheung CC, Scheinman M. A smart interpretation of the smartwatch ECG: consider the false negatives. Europace 2022; 24:1710. [PMID: 35654765 DOI: 10.1093/europace/euac070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 04/10/2022] [Indexed: 11/14/2022] Open
Affiliation(s)
- Christopher C Cheung
- Section of Cardiac Electrophysiology, University of California San Francisco, 505 Parnassus Avenue 94143 San Francisco, USA
| | - Melvin Scheinman
- Section of Cardiac Electrophysiology, University of California San Francisco, 505 Parnassus Avenue 94143 San Francisco, USA
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10
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Scheinman M, Bunch TJ, Singh M. A tale of 2 torsades: How to approach a patient with torsades de pointes and distinguish between classical and pseudo–torsades de pointes. HeartRhythm Case Rep 2022; 8:305-308. [PMID: 35497484 PMCID: PMC9039100 DOI: 10.1016/j.hrcr.2022.03.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- Melvin Scheinman
- Division of Cardiology, Section on Electrophysiology, University of California San Francisco, San Francisco, California
| | - T. Jared Bunch
- Division of Cardiology, Department of Internal Medicine, University of Utah, Utah
| | - Mohita Singh
- Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Address reprint requests and correspondence: Dr Mohita Singh, Division of Cardiology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX.
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11
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Cheung CC, Scheinman M, Lee BK. A peculiar case of palpitations and syncope. Heart Rhythm 2022; 19:505-507. [DOI: 10.1016/j.hrthm.2021.11.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/11/2021] [Accepted: 11/12/2021] [Indexed: 11/30/2022]
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12
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Aboyme A, Coromilas J, Scheinman M, Kassotis J. Exercise Induced Brugada Syndrome Type I Pattern. HeartRhythm Case Rep 2022; 8:288-291. [PMID: 35497475 PMCID: PMC9039088 DOI: 10.1016/j.hrcr.2022.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Affiliation(s)
| | | | | | - John Kassotis
- Address reprint requests and correspondence: Dr John Kassotis, Rutgers, Robert Wood Johnson Medical School, 125 Paterson St, Medical Education Building 5 Floor, Room 582, New Brunswick, NJ 08901.
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13
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Sung RK, Boyden PA, Higuchi S, Scheinman M. Diagnosis and Management of Complex Reentrant Arrhythmias Involving the His-Purkinje System. Arrhythm Electrophysiol Rev 2021; 10:190-197. [PMID: 34777824 PMCID: PMC8576512 DOI: 10.15420/aer.2021.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 07/13/2021] [Indexed: 11/04/2022] Open
Abstract
The His-Purkinje system is a network of bundles and fibres comprised of specialised cells that allow for coordinated, synchronous activation of the ventricles. Although the histology and physiology of the His-Purkinje system have been studied for more than a century, its role in ventricular arrhythmias has recently been discovered with the ongoing elucidation of the mechanisms leading to both benign and life-threatening arrhythmias. Studies of Purkinje-cell electrophysiology show multiple mechanisms responsible for ventricular arrhythmias, including enhanced automaticity, triggered activity and reentry. The variation in functional properties of Purkinje cells in different areas of the His-Purkinje system underlie the propensity for reentry within Purkinje fibres in structurally normal and abnormal hearts. Catheter ablation is an effective therapy in nearly all forms of reentrant arrhythmias involving Purkinje tissue. However, identifying those at risk of developing fascicular arrhythmias is not yet possible. Future research is needed to understand the precise molecular and functional changes resulting in these arrhythmias.
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Affiliation(s)
| | | | - Satoshi Higuchi
- University of California San Francisco, San Francisco, CA, US
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14
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Yoruk A, Scheinman M. Sudden death in a "healthy" youth: Lessons learned. Heart Rhythm 2021; 18:1886-1887. [PMID: 34752259 DOI: 10.1016/j.hrthm.2021.06.1199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 06/24/2021] [Indexed: 10/20/2022]
Affiliation(s)
- Ayhan Yoruk
- Division of Cardiology, University of California San Francisco, San Francisco, California
| | - Melvin Scheinman
- Division of Cardiology, University of California San Francisco, San Francisco, California.
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15
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Howell SJ, Lee A, Scheinman M. Supraventricular tachycardia with double trouble. Heart Rhythm 2021; 19:1569-1570. [PMID: 34757191 DOI: 10.1016/j.hrthm.2021.10.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 10/22/2021] [Accepted: 10/22/2021] [Indexed: 11/04/2022]
Affiliation(s)
- Stacey J Howell
- Section of Cardiac Electrophysiology, Division of Cardiology, University of California San Francisco, San Francisco, California.
| | - Adam Lee
- Section of Cardiac Electrophysiology, Division of Cardiology, University of California San Francisco, San Francisco, California
| | - Melvin Scheinman
- Section of Cardiac Electrophysiology, Division of Cardiology, University of California San Francisco, San Francisco, California
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16
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Zhang ZH, Barajas-Martínez H, Xia H, Li B, Capra JA, Clatot J, Chen GX, Chen X, Yang B, Jiang H, Tse G, Aizawa Y, Gollob MH, Scheinman M, Antzelevitch C, Hu D. Distinct Features of Probands With Early Repolarization and Brugada Syndromes Carrying SCN5A Pathogenic Variants. J Am Coll Cardiol 2021; 78:1603-1617. [PMID: 34649698 DOI: 10.1016/j.jacc.2021.08.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 08/06/2021] [Accepted: 08/10/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND Two major forms of inherited J-wave syndrome (JWS) are recognized: early repolarization syndrome (ERS) and Brugada syndrome (BrS). OBJECTIVES This study sought to assess the distinct features between patients with ERS and BrS carrying pathogenic variants in SCN5A. METHODS Clinical evaluation and next-generation sequencing were performed in 262 probands with BrS and 104 with ERS. Nav1.5 and Kv4.3 channels were studied with the use of patch-clamp techniques. A computational model was used to investigate the protein structure. RESULTS The SCN5A+ yield in ERS was significantly lower than in BrS (9.62% vs 22.90%; P = 0.004). Patients diagnosed with ERS displayed shorter QRS and QTc than patients with BrS. More than 2 pathogenic SCN5A variants were found in 5 probands. These patients displayed longer PR intervals and QRS duration and experienced more major arrhythmia events (MAE) compared with those carrying only a single pathogenic variant. SCN5A-L1412F, detected in a fever-induced ERS patient, led to total loss of function, destabilized the Nav1.5 structure, and showed a dominant-negative effect, which was accentuated during a febrile state. ERS-related SCN5A-G452C did not alter the inward sodium current (INa) when SCN5A was expressed alone, but when coexpressed with KCND3 it reduced peak INa by 44.52% and increased the transient outward potassium current (Ito) by 106.81%. CONCLUSIONS These findings point to SCN5A as a major susceptibility gene in ERS as much as it is in BrS, whereas the lower SCN5A+ ratio in ERS indicates the difference in underlying electrophysiology. These findings also identify the first case of fever-induced ERS and demonstrate a critical role of Ito in JWS and a higher risk for MAE in JWS probands carrying multiple pathogenic variants in SCN5A.
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Affiliation(s)
- Zhong-He Zhang
- Department of Cardiology and Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan, Hubei, China; Hubei Key Laboratory of Cardiology, Wuhan, Hubei, China
| | - Hector Barajas-Martínez
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA; Lankenau Heart Institute, Wynnewood, Pennsylvania, USA; Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Hao Xia
- Department of Cardiology and Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan, Hubei, China; Hubei Key Laboratory of Cardiology, Wuhan, Hubei, China
| | - Bian Li
- Department of Biological Sciences, Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA; Vanderbilt Genetics Institute, Vanderbilt University, Nashville, Tennessee, USA
| | - John A Capra
- Bakar Computational Health Sciences Institute, University of California, San Francisco, California, USA
| | - Jerome Clatot
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Gan-Xiao Chen
- Department of Cardiology and Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan, Hubei, China; Hubei Key Laboratory of Cardiology, Wuhan, Hubei, China
| | - Xiu Chen
- Department of Cardiology and Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan, Hubei, China; Hubei Key Laboratory of Cardiology, Wuhan, Hubei, China
| | - Bo Yang
- Department of Cardiology and Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan, Hubei, China; Hubei Key Laboratory of Cardiology, Wuhan, Hubei, China
| | - Hong Jiang
- Department of Cardiology and Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan, Hubei, China; Hubei Key Laboratory of Cardiology, Wuhan, Hubei, China
| | - Gary Tse
- 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; Kent and Medway Medical School, Canterbury, Kent, United Kingdom
| | - Yoshiyasu Aizawa
- Department of Cardiovascular Medicine, School of Medicine 4-3, International University of Health and Welfare, Kozunomori, Narita, Chiba, Japan
| | - Michael H Gollob
- Department of Physiology and Division of Cardiology, University of Toronto, Toronto, Ontario, Canada
| | - Melvin Scheinman
- Department of Cardiac Electrophysiology, University of California, San Francisco, California, USA
| | - Charles Antzelevitch
- Lankenau Institute for Medical Research, Wynnewood, Pennsylvania, USA; Lankenau Heart Institute, Wynnewood, Pennsylvania, USA; Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Dan Hu
- Department of Cardiology and Cardiovascular Research Institute, Renmin Hospital of Wuhan University, Wuhan, Hubei, China; Hubei Key Laboratory of Cardiology, Wuhan, Hubei, China.
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17
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Zhang J, Zanella F, Bradford WH, Fujita K, Karakikes I, Lyon RC, Mezzano V, Roberts JD, Carromeu C, Gu Y, Martin JL, Muotri AR, Scheinman M, Peterson KL, Sheikh F. Abstract P449: Connexin43 As A Therapeutic For Arrhythmogenic Right Ventricular Cardiomyopathy. Circ Res 2021. [DOI: 10.1161/res.129.suppl_1.p449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Limited efforts have been focused on the interventions which could therapeutically alter arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C), a fatal cardiac disease of the desmosomal (mechanical) cell-cell junction. The desmosome is a critical target for intervention as mutations in desmosomal genes underlie 40-50% of ARVD/C populations and its dysregulation is associated with severe cardiac electrical and structural alterations, which facilitate myocardial failure, arrhythmias and premature death in these populations. Cardiomyocyte reduction of the predominant ventricular gap junction protein connexin43 is a molecular alteration that underlies desmosomal deficits and arrhythmias in ARVD/C. However, the role of connexin43 in structural alterations associated with ARVD/C remains unclear. We intervened with connexin43 reduction in human and mouse models of ARVD/C via connexin43 restoration strategies, which revealed beneficial effects in both ARVD/C models. We show ARVD/C human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes that recapitulate desmosomal structural defects and reveal connexin43 diminution alterations that are reflective of disease found in donor ARVD/C hearts. Connexin43 restoration was sufficient to rescue cardiac physiological deficits and increase desmosomal gene expressions in ARVD/C hiPSC derived cardiomyocytes, encompassing structural alterations.
In vivo
studies exploiting a mouse model of ARVD/C harboring severe desmosomal structural alterations revealed that cardiac connexin43 restoration was sufficient to prolong lifespan and restore cardiac desmosomal proteins. Herein, we provide evidence for non-canonical functions for connexin43, classically associated with electrical function, in the mechanical modulation of junctions. Our findings have broad implications in exploiting connexin43 as a therapeutic in advanced diseases associated with cardiac structural defects.
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18
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Liang Y, Lyon R, Pellman J, Bradford W, Lange S, Bogomolovas J, Dalton N, Gu Y, Bobar M, Lee MH, Iwakuma T, Nigam V, Asimaki A, Scheinman M, Peterson KL, Sheikh F. Abstract MP218: Cop9 Signalosome Subunit 6 Restricts Desmosomal Proteome Degradation To Prevent Desmosomal Targeted Cardiac Disease. Circ Res 2021. [DOI: 10.1161/res.129.suppl_1.mp218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Dysregulated protein degradative pathways are increasingly recognized as mediators of human cardiac disease. This pathway may have particular relevance to desmosomal proteins that play critical structural roles in both tissue architecture and cell-cell communication. Genetic mutations in desmosomal genes resulting in the destabilization/breakdown of the desmosomal proteome are a central hallmark of all genetic-based desmosomal-targeted diseases, including the cardiac disease arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C). However, no information exists on whether there are resident proteins that regulate desmosomal proteome homeostasis. Here we identified a desmosomal resident regulatory complex, composed of subunit 6 of the COP9 signalosome (CSN6), enzymatically restricted neddylation and targets desmosomal proteome. Pharmacological restoration of CSN enzymatic function (via neddylation inhibitors) could rescue desmosomal protein loss in CSN6 deficient cardiomyocytes. Through the generation of two novel mouse models, we showed that cardiomyocyte-restricted CSN6 loss in mice selectively accelerated desmosomal destruction to trigger classic disease features associated with ARVD/C. We further showed that disruption of CSN6-mediated (neddylation) pathways underlined ARVD/C as CSN6 binding, localization, levels and function were impacted in hearts of classic ARVD/C mouse models and ARVD/C patients impacted by desmosomal loss and mutations, respectively. We anticipate our findings have broad implications towards understanding mechanisms driving desmosome degradation in other desmosomal-based diseases, such as cancers.
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Affiliation(s)
- Yan Liang
- Univ of California-San Diego, La Jolla, CA
| | | | | | | | | | | | | | | | | | - Mong-Hong Lee
- The Univ of Texas MD Anderson Cancer Cntr, Houston, TX
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19
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Affiliation(s)
- Christopher Cheung
- Section of Cardiac Electrophysiology, University of California-San Francisco, San Francisco, California, USA
| | - Melvin Scheinman
- Section of Cardiac Electrophysiology, University of California-San Francisco, San Francisco, California, USA
| | - Henry Hsia
- Section of Cardiac Electrophysiology, University of California-San Francisco, San Francisco, California, USA.
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20
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Higuchi S, Sarcon A, Sternick EB, Sanchez-Quintana D, Anderson RH, Scheinman M, Hsia H. Isolated Left-Sided Accessory Pathway Potential: The Potential Possibilities. JACC Clin Electrophysiol 2021; 7:1316-1323. [PMID: 34332873 DOI: 10.1016/j.jacep.2021.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/18/2021] [Accepted: 05/19/2021] [Indexed: 10/20/2022]
Affiliation(s)
- Satoshi Higuchi
- Division of Cardiology, Section of Cardiac Electrophysiology, University of California, San Francisco, San Francisco, California, USA
| | - Annahita Sarcon
- Division of Cardiology, Section of Cardiac Electrophysiology, University of California, San Francisco, San Francisco, California, USA
| | | | | | - Robert H Anderson
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Melvin Scheinman
- Division of Cardiology, Section of Cardiac Electrophysiology, University of California, San Francisco, San Francisco, California, USA. https://twitter.com/MelScheinman
| | - Henry Hsia
- Division of Cardiology, Section of Cardiac Electrophysiology, University of California, San Francisco, San Francisco, California, USA.
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21
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Liang Y, Lyon RC, Pellman J, Bradford WH, Lange S, Bogomolovas J, Dalton ND, Gu Y, Bobar M, Lee MH, Iwakuma T, Nigam V, Asimaki A, Scheinman M, Peterson KL, Sheikh F. Desmosomal COP9 regulates proteome degradation in arrhythmogenic right ventricular dysplasia/cardiomyopathy. J Clin Invest 2021; 131:137689. [PMID: 33857019 PMCID: PMC8159691 DOI: 10.1172/jci137689] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 04/14/2021] [Indexed: 12/28/2022] Open
Abstract
Dysregulated protein degradative pathways are increasingly recognized as mediators of human disease. This mechanism may have particular relevance to desmosomal proteins that play critical structural roles in both tissue architecture and cell-cell communication, as destabilization/breakdown of the desmosomal proteome is a hallmark of genetic-based desmosomal-targeted diseases, such as the cardiac disease arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). However, no information exists on whether there are resident proteins that regulate desmosomal proteome homeostasis. Here, we uncovered a cardiac constitutive photomorphogenesis 9 (COP9) desmosomal resident protein complex, composed of subunit 6 of the COP9 signalosome (CSN6), that enzymatically restricted neddylation and targeted desmosomal proteome degradation. CSN6 binding, localization, levels, and function were affected in hearts of classic mouse and human models of ARVD/C affected by desmosomal loss and mutations, respectively. Loss of desmosomal proteome degradation control due to junctional reduction/loss of CSN6 and human desmosomal mutations destabilizing junctional CSN6 were also sufficient to trigger ARVD/C in mice. We identified a desmosomal resident regulatory complex that restricted desmosomal proteome degradation and disease.
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Affiliation(s)
- Yan Liang
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Robert C. Lyon
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Jason Pellman
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - William H. Bradford
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Stephan Lange
- Department of Medicine, University of California San Diego, La Jolla, California, USA
- Institute of Medicine, Department of Molecular and Clinical Medicine and Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Julius Bogomolovas
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Nancy D. Dalton
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Yusu Gu
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Marcus Bobar
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Mong-Hong Lee
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Tomoo Iwakuma
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Vishal Nigam
- Department of Pediatrics, University of California San Diego, La Jolla, California, USA
- Department of Pediatrics, Seattle Children’s Research Institute and University of Washington, Seattle, Washington, USA
| | - Angeliki Asimaki
- Cardiology Clinical Academic Group, St. George’s University of London, London, United Kingdom
| | - Melvin Scheinman
- Department of Medicine, Cardiac Electrophysiology Section, University of California San Francisco, San Francisco, California, USA
| | - Kirk L. Peterson
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Farah Sheikh
- Department of Medicine, University of California San Diego, La Jolla, California, USA
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22
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Im SI, Voskoboinik A, Lee A, Higuchi S, Moss JD, Hsia H, Tseng ZH, Lee R, Marcus GM, Vedantham V, Scheinman M, Lee B, Park KM, Gerstenfeld EP. Predictors of long-term success after catheter ablation of premature ventricular complexes. J Cardiovasc Electrophysiol 2021; 32:2254-2261. [PMID: 34041816 DOI: 10.1111/jce.15114] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 04/23/2021] [Accepted: 05/17/2021] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Some patients have late recurrence after acutely successful radiofrequency catheter ablation (RFCA) of premature ventricular complexes (PVCs). The aim of this study was to evaluate predictors of long-term success following acutely successful PVC RFCA. METHODS We identified consecutive patients at our institution with frequent PVCs undergoing RFCA and reviewed procedural data and medical records. Acute success was defined as elimination of targeted PVCs for at least 30-min after RFCA. Long-term success was defined as absence of targeted PVCs during all follow-up visits and PVC-burden <5% on follow-up monitoring. RESULTS Among 241 patients (mean age 57 ± 15 years, 58% male), 161 (66.8%) had long-term success with median follow-up of 17.7 (IQR, 12.2-29.8) months. Unadjusted predictors of late PVC recurrence were increasing age, diabetes mellitus and alcohol use, while female-sex, shorter ablation-time, right ventricular PVC-origin, single PVC morphology, and earliest bipolar activation ≥24 ms pre-QRS were predictors of long-term success. In multivariate-analysis, female-sex, single-PVC morphology and earliest-onset of PVC ≥ 24 ms pre-QRS were independent predictors for long-term success. The positive-predictive value of earliest-bipolar onset of PVC ≥ 24 ms pre-QRS for long-term success was 0.77 (p < .001). Negative-predictive value of PVC < 15 ms pre-QRS for long-term success was 0.86 (p = .003), suggesting that RFCA when the bipolar electrogram preceded QRS by <15 ms was unlikely to result in long-term success. CONCLUSIONS Female-sex, single-PVC morphology, and earliest-onset of bipolar electrogram ≥24 ms pre-QRS were multivariable predictors of long-term success in patients with PVCs undergoing RFCA. RFCA at sites with local onset <15 ms pre-QRS are unlikely to be successful.
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Affiliation(s)
- Sung-Il Im
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Aleksandr Voskoboinik
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Adam Lee
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Satoshi Higuchi
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Joshua D Moss
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Henry Hsia
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Zian H Tseng
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Randall Lee
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Gregory M Marcus
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Vasanth Vedantham
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Melvin Scheinman
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Byron Lee
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
| | - Kyoung-Min Park
- Division of Cardiology, Heart Vascular and Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Edward P Gerstenfeld
- Department of Medicine, Division of Cardiology, Section of Cardiac Electrophysiology, University of California San Francisco, San Francisco, California, USA
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23
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Liang Y, Lyon R, Pellman J, Bradford W, Lange S, Bogomolovas J, Dalton N, Gu Y, Bobar M, Lee M, Iwakuma T, Nigam V, Scheinman M, Peterson K, Sheikh F. Desmosomal COP9 regulates proteome degradation in arrhythmogenic right ventricular dysplasia/cardiomyopathy. FASEB J 2021. [DOI: 10.1096/fasebj.2021.35.s1.04838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yan Liang
- University of California‐San DiegoLa JollaCA
| | - Robert Lyon
- University of California‐San DiegoLa JollaCA
| | | | | | | | | | | | - Yusu Gu
- University of California‐San DiegoLa JollaCA
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24
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Zhang J, Zanella F, Lyon R, Mezzano V, Roberts J, Ursell P, Carromeu C, Gu Y, Martin J, Muotri A, Scheinman M, Peterson K, Sheikh F. Connexin43 as a Gene Therapy To Circumvent Arrhythmogenic Cardiomyopathy. FASEB J 2021. [DOI: 10.1096/fasebj.2021.35.s1.04812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jing Zhang
- University of California‐San DiegoSan DiegoCA
| | | | - Robert Lyon
- University of California‐San DiegoSan DiegoCA
| | | | - Jason Roberts
- University of California‐San FranciscoSan FranciscoCA
| | - Philip Ursell
- University of California‐San FranciscoSan FranciscoCA
| | | | - Yusu Gu
- University of California‐San DiegoSan DiegoCA
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25
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Thakkar AB, Scheinman M, Goldschlager N. Ventricular Preexcitation in a Patient Found to Have Wolff-Parkinson-White Pattern. JAMA Intern Med 2021; 181:262-263. [PMID: 33315092 DOI: 10.1001/jamainternmed.2020.6847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Anjali B Thakkar
- Department of Medicine, University of California, San Francisco, San Francisco
| | - Melvin Scheinman
- Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco
| | - Nora Goldschlager
- Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco.,Division of Cardiology, Department of Medicine, Zuckerberg San Francisco General Hospital and Trauma Center, San Francisco, California.,Section Editor, JAMA Internal Medicine
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26
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Cheung CC, Sarcon A, Belhassen B, Scheinman M. Twirling around the block-A complex case of cardiac sarcoidosis. Heart Rhythm 2021; 18:151-153. [PMID: 33413950 DOI: 10.1016/j.hrthm.2020.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 08/15/2020] [Accepted: 08/19/2020] [Indexed: 11/26/2022]
Affiliation(s)
- Christopher C Cheung
- Division of Cardiology, University of California, San Francisco, San Francisco, California
| | - Annahita Sarcon
- Division of Cardiology, University of California, San Francisco, San Francisco, California
| | - Bernard Belhassen
- Division of Cardiology, University of California, San Francisco, San Francisco, California
| | - Melvin Scheinman
- Division of Cardiology, University of California, San Francisco, San Francisco, California.
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27
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Voskoboinik A, Hadjis A, Alhede C, Im SI, Park H, Moss J, Marcus GM, Hsia H, Lee B, Tseng Z, Lee R, Scheinman M, Vedantham V, Vittinghoff E, Park KM, Gerstenfeld EP. Predictors of adverse outcome in patients with frequent premature ventricular complexes: The ABC-VT risk score. Heart Rhythm 2020; 17:1066-1074. [DOI: 10.1016/j.hrthm.2020.02.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 02/14/2020] [Indexed: 12/21/2022]
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28
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Zhang J, Zanella F, Lyon R, Mezzano V, Roberts J, Ursell P, Carromeu C, Gu Y, Martin J, Muotri AR, Scheinman M, Peterson KL, Sheikh F. Connexin43 as a Therapeutic To Restore Cardiac Structure in Arrhythmogenic Heart Disease. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.06280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | | | | | | | | | - Yusu Gu
- University of California-San Diego
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29
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Kalantarian S, Scheinman M. J-WAVE SYNDROMES WITH OVERLAPPING PHENOTYPIC EXPRESSION MIMICKING BRUGADA SYNDROME AND EARLY REPOLARIZATION SYNDROME. J Am Coll Cardiol 2020. [DOI: 10.1016/s0735-1097(20)33241-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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30
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Hammami Bomholtz S, Refaat M, Buur Steffensen A, David J, Espinosa K, Nussbaum R, Wojciak J, Hjorth Bentzen B, Scheinman M, Schmitt N. Functional phenotype variations of two novel K
V
7.1 mutations identified in patients with Long QT syndrome. Pacing Clin Electrophysiol 2020; 43:210-216. [DOI: 10.1111/pace.13870] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 12/20/2019] [Accepted: 12/29/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Sofia Hammami Bomholtz
- Danish National Research Foundation Centre for Cardiac ArrhythmiaUniversity of Copenhagen Copenhagen Denmark
- Department of Biomedical SciencesUniversity of Copenhagen Copenhagen Denmark
| | - Marwan Refaat
- Department of Internal Medicine, Division of CardiologyAmerican University of Beirut Medical Center Beirut Lebanon
- Department of Biochemistry and Molecular GeneticsAmerican University of Beirut Beirut Lebanon
| | - Annette Buur Steffensen
- Danish National Research Foundation Centre for Cardiac ArrhythmiaUniversity of Copenhagen Copenhagen Denmark
- Department of Biomedical SciencesUniversity of Copenhagen Copenhagen Denmark
| | - Jens‐Peter David
- Danish National Research Foundation Centre for Cardiac ArrhythmiaUniversity of Copenhagen Copenhagen Denmark
- Department of Biomedical SciencesUniversity of Copenhagen Copenhagen Denmark
| | - Karin Espinosa
- Danish National Research Foundation Centre for Cardiac ArrhythmiaUniversity of Copenhagen Copenhagen Denmark
- Department of Biomedical SciencesUniversity of Copenhagen Copenhagen Denmark
| | - Robert Nussbaum
- Department of MedicineUniversity of California, San Francisco San Francisco California
| | - Julianne Wojciak
- Department of MedicineUniversity of California, San Francisco San Francisco California
| | - Bo Hjorth Bentzen
- Danish National Research Foundation Centre for Cardiac ArrhythmiaUniversity of Copenhagen Copenhagen Denmark
- Department of Biomedical SciencesUniversity of Copenhagen Copenhagen Denmark
| | - Melvin Scheinman
- Department of MedicineUniversity of California, San Francisco San Francisco California
| | - Nicole Schmitt
- Danish National Research Foundation Centre for Cardiac ArrhythmiaUniversity of Copenhagen Copenhagen Denmark
- Department of Biomedical SciencesUniversity of Copenhagen Copenhagen Denmark
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31
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Liang Y, Lyon RC, Pellman J, Mezzano V, Gu Y, Dalton N, Bradford W, Bogomolovas J, Lee M, Iwakuma T, Nigam V, Scheinman M, Peterson K, Sheikh F. Discovery of Protein Degradation Machinery at the Desmosome Reveals Novel Triggers of the Desmosomal Disease, Arrhythmogenic Right Ventricular Cardiomyopathy. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.829.6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yan Liang
- University of California‐San DiegoSan DiegoCA
| | | | | | | | - Yusu Gu
- University of California‐San DiegoSan DiegoCA
| | | | | | | | - Mong‐Hong Lee
- Molecular and Cellular OncologyThe University of Texas MD Anderson Cancer CenterHoustonTX
| | - Tomoo Iwakuma
- Cancer BiologyUniversity of Kansas Medical CenterKansas CityKS
| | | | - Melvin Scheinman
- University of CaliforniaSan Francisco Medical CenterSan FranciscoCA
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32
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He BJ, Boyden P, Scheinman M. Ventricular arrhythmias involving the His-Purkinje system in the structurally abnormal heart. Pacing Clin Electrophysiol 2018; 41:1051-1059. [PMID: 30084120 DOI: 10.1111/pace.13465] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 06/28/2018] [Accepted: 07/05/2018] [Indexed: 12/01/2022]
Abstract
His-Purkinje-related ventricular arrhythmias are a subset of ventricular tachycardias that use the specialized cardiac conduction system. These arrhythmias can occur in various different forms of structural heart disease. Here, we review the basic science discoveries and their analogous clinical observations that implicate the His-Purkinje system as a crucial component of the arrhythmia circuit. While mutations serve the molecular basis for arrhythmias in the heritable cardiomyopathies, transcriptional and posttranslational changes constitute the adverse remodeling leading to arrhythmias in acquired structural heart disease. Additional studies on the electrical properties of the His-Purkinje network and its interactions with the surrounding myocardium will improve the clinical diagnosis and treatment of these arrhythmias.
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Affiliation(s)
- Beixin Julie He
- Department of Medicine, University of California, San Francisco, California
| | - Penelope Boyden
- Department of Pharmacology, Columbia University, New York city, New York
| | - Melvin Scheinman
- Department of Medicine, University of California, San Francisco, California
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33
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Denti F, Bentzen BH, Wojciak J, Thomsen NM, Scheinman M, Schmitt N. Multiple genetic variations in sodium channel subunits in a case of sudden infant death syndrome. Pacing Clin Electrophysiol 2018; 41:620-626. [PMID: 29572929 DOI: 10.1111/pace.13328] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 02/15/2018] [Accepted: 02/25/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND Dysfunction of NaV 1.5 encoded by SCN5A accounts for approximately half of the channelopathic SIDS cases. We investigated the functional effect of two gene variants identified in the same patient, one in SCN5A and one in SCN1Bb. The aim of the study was to risk stratify the proband's family. METHODS The family was referred for cardiovascular genetic evaluation to assess familial risk of cardiac disease. Functional analysis of the identified variants was performed with patch-clamp electrophysiology in HEK293 cells. RESULTS A 16-month-old healthy boy died suddenly in the context of nonspecific illness and possible fever. Postmortem genetic testing revealed variants in the SCN5A and SCN1Bb genes. The proband's father carries the same variants but is asymptomatic. Electrophysiological analysis of the NaV 1.5_1281X truncation revealed complete loss-of-function of the channel. Coexpression of NaV 1.5 with NaV β1b significantly increased INa density when compared to NaV 1.5 alone. The NaV β1b _V268I variant abolished this INa density increase. Moreover, it shifted the activation curve toward more depolarized potentials. CONCLUSIONS Genetic variation of both sodium channel and its modifiers may contribute to sudden unexplained death in childhood. However, the asymptomatic father suggests that genetic variation of these genes is not sufficient to cause sudden death or clinically detectable SCN5A phenotypes.
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Affiliation(s)
- Federico Denti
- Danish National Research Foundation Centre for Cardiac Arrhythmia and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bo Hjorth Bentzen
- Danish National Research Foundation Centre for Cardiac Arrhythmia and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Julianne Wojciak
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Nancy Mutsaers Thomsen
- Danish National Research Foundation Centre for Cardiac Arrhythmia and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Melvin Scheinman
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Nicole Schmitt
- Danish National Research Foundation Centre for Cardiac Arrhythmia and Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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34
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Tracy CM, Crossley GH, Bunch TJ, Chow GV, Leiserowitz A, Indik JH, Kusumoto F, Mendes LA, Munger TM, Murali S, Patton KK, Russo AM, Scheinman M, Schoenhard JA, Winterfield JR. 2017 ACC/HRS lifelong learning statement for clinical cardiac electrophysiology specialists. Heart Rhythm 2018; 15:e17-e34. [DOI: 10.1016/j.hrthm.2017.11.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Indexed: 11/29/2022]
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35
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Tracy CM, Crossley GH, Bunch TJ, Chow GV, Leiserowitz A, Indik JH, Kusumoto F, Mendes LA, Munger TM, Murali S, Patton KK, Russo AM, Scheinman M, Schoenhard JA, Winterfield JR. 2017 ACC/HRS Lifelong Learning Statement for Clinical Cardiac Electrophysiology Specialists. J Am Coll Cardiol 2018; 71:231-250. [DOI: 10.1016/j.jacc.2017.11.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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36
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Scheinman M. ELECTROPHYSIOLOGICAL FOUNDATIONS OF CARDIAC ARRHYTHMIAS Andrew L. Wit Hein J. Wellens Mark E. Josephson Cardiotext Publishing, LLC, ISBN: 978-0-9790164-5-5, 648. Pacing Clin Electrophysiol 2017. [DOI: 10.1111/pace.13198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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37
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Affiliation(s)
- Henry H Hsia
- Cardiac Electrophysiology Service, University of California, San Francisco, San Francisco, California.
| | - Melvin Scheinman
- Cardiac Electrophysiology Service, University of California, San Francisco, San Francisco, California
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38
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Refaat M, Bomholtz S, Steffensen A, David J, Espinosa K, Bentzen B, Nussbaum R, Wojciak J, Scheinman M, Schmitt N. P5859Genotype-phenotype correlation of novel KV7.1 mutations identified in patients with Long QT syndrome. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx493.p5859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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39
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Szilágyi J, Marcus GM, Badhwar N, Lee BK, Lee RJ, Vedantham V, Tseng ZH, Walters T, Scheinman M, Olgin J, Gerstenfeld EP. Cover Image, Volume 28, Issue 7. J Cardiovasc Electrophysiol 2017. [DOI: 10.1111/jce.13305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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40
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Szilágyi J, Marcus GM, Badhwar N, Lee BK, Lee RJ, Vedantham V, Tseng ZH, Walters T, Scheinman M, Olgin J, Gerstenfeld EP. Atrial fibrillation patients with isolated pulmonary veins: Is sinus rhythm achievable? J Cardiovasc Electrophysiol 2017; 28:754-761. [PMID: 28429499 DOI: 10.1111/jce.13230] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/01/2017] [Accepted: 04/05/2017] [Indexed: 11/30/2022]
Abstract
BACKGROUND The cornerstone of atrial fibrillation (AF) ablation is isolation of the pulmonary veins (PVs). Patients with recurrent AF undergoing repeat ablation usually have PV reconnection (PVr). The ablation strategy and outcome of patients undergoing repeat ablation who have persistent isolation of all PVs (PVi) at the time of repeat ablation is unknown. METHODS AND RESULTS We studied consecutive patients with recurrent AF undergoing repeat ablation and compared patients with PVi to those with PVr. One hundred fifty-two patients underwent repeat ablation, and of these, 25 patients (16.4%) had PVi. Patients with PVi underwent ablation targeting any isoproterenol induced AF triggers, atrial substrate, or inducible atrial tachycardias or flutters. Patients with PVi compared to PVr were more likely to have a history of persistent AF (64% vs. 26%; P < 0.0001), obesity (BMI 30.4 vs. 28.2; P = 0.05), and prior use of contact force sensing catheters (28% vs. 0.8%, P < 0.0001). After a mean follow-up of 19 ± 15 months, 56% of PVi patients remained in sinus rhythm compared to 76.3% of PVr patients (P = 0.036). In a multivariable model, PVi patients and those with cardiomyopathy had a higher risk of recurrent atrial tachyarrhythmias (HR = 3.6 95%, CI 1.6-8.3, P = 0.002 and HR = 6.2, 95% CI 2.3-16.3, P < 0.0001, respectively). CONCLUSION In patients who have all PVs isolated at the time of the redo AF ablation, a strategy of targeting non-PV AF triggers and inducible flutters can still lead to AF freedom in more than half of patients. Patients with PVr, however, have a better long-term outcome.
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Affiliation(s)
- Judit Szilágyi
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Gregory M Marcus
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Nitish Badhwar
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Byron K Lee
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Randall J Lee
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Vasanth Vedantham
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Zian H Tseng
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Tomos Walters
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Melvin Scheinman
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Jeffrey Olgin
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
| | - Edward P Gerstenfeld
- Section of Cardiac Electrophysiology and Arrhythmia Service, Division of Cardiology, University of California, San Francisco, CA, USA
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41
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Scheinman M. SVT Therapy – Yesterday, Today and Tomorrow? J Atr Fibrillation 2016; 9:1506. [DOI: 10.4022/jafib.1506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 12/19/2016] [Accepted: 12/25/2016] [Indexed: 11/10/2022]
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Abstract
Bidirectional ventricular tachycardia (BDVT) is a well-known phenomenon since it was first described in 1922. Various mechanisms have been proposed for BDVT, including digitalis toxicity, hypokalemia, Anderson-Tawil syndrome, acute myocarditis, and catecholaminergic polymorphic ventricular tachycardia. It is characterized by rapid, wide complex electrocardiogram pattern with alternating QRS morphology and axis. The alternation of the QRS is usually right bundle branch block with 180° swings in the frontal plane axis or, less commonly, alternation of right bundle branch and left bundle branch forms. Most of the proposed mechanisms involve triggered activity or enhanced automaticity. We describe a unique BDVT, with characteristics of both re-entry and triggered activity, which terminated with a focal Rf lesion.
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Affiliation(s)
- Sarfraz A Durrani
- MedStar Heart and Vascular Institute, #501 Hamaker court, Fairfax, VA 22031, USA.
| | - Raphael Sung
- Peninsula Primary Care, Cardiology, 30 Garden Court, Suite B, Monterey, CA 93940, USA
| | - Melvin Scheinman
- University of California San Francisco Medical Center, 500 Parnassus Avenue, MUE 436, San Francisco, CA 94143-1354, USA
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Abstract
Fascicular arrhythmias encompass a wide spectrum of ventricular arrhythmias that depend on the specialized conduction system of the right and left ventricles. These arrhythmias include premature ventricular complexes, monomorphic ventricular tachycardia, polymorphic ventricular tachycardia, and ventricular fibrillation. These arrhythmias may be organized by mechanism, including intrafascicular reentry, interfascicular reentry, and focal. Mapping and ablation of the fascicular system can result in high cure rates of debilitating and potentially life-threatening arrhythmias. When approaching these arrhythmias, careful consideration of the structure of the His Purkinje system as well as their electrophysiologic properties may help guide even the most complex of arrhythmias.
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Affiliation(s)
- Raphael Sung
- Community Hospital of the Monterey Peninsula, Monterey, CA, USA
| | - Melvin Scheinman
- University of California San Francisco, 350 Parnassus Avenue, #300, San Francisco, CA 94117, USA.
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Mezzano V, Liang Y, Wright AT, Lyon RC, Pfeiffer E, Song MY, Gu Y, Dalton ND, Scheinman M, Peterson KL, Evans SM, Fowler S, Cerrone M, McCulloch AD, Sheikh F. Desmosomal junctions are necessary for adult sinus node function. Cardiovasc Res 2016; 111:274-86. [PMID: 27097650 DOI: 10.1093/cvr/cvw083] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 04/08/2016] [Indexed: 12/20/2022] Open
Abstract
AIMS Current mechanisms driving cardiac pacemaker function have focused on ion channel and gap junction channel function, which are essential for action potential generation and propagation between pacemaker cells. However, pacemaker cells also harbour desmosomes that structurally anchor pacemaker cells to each other in tissue, but their role in pacemaker function remains unknown. METHODS AND RESULTS To determine the role of desmosomes in pacemaker function, we generated a novel mouse model harbouring cardiac conduction-specific ablation (csKO) of the central desmosomal protein, desmoplakin (DSP) using the Hcn4-Cre-ERT2 mouse line. Hcn4-Cre targets cells of the adult mouse sinoatrial node (SAN) and can ablate DSP expression in the adult DSP csKO SAN resulting in specific loss of desmosomal proteins and structures. Dysregulation of DSP via loss-of-function (adult DSP csKO mice) and mutation (clinical case of a patient harbouring a pathogenic DSP variant) in mice and man, respectively, revealed that desmosomal dysregulation is associated with a primary phenotype of increased sinus pauses/dysfunction in the absence of cardiomyopathy. Underlying defects in beat-to-beat regulation were also observed in DSP csKO mice in vivo and intact atria ex vivo. DSP csKO SAN exhibited migrating lead pacemaker sites associated with connexin 45 loss. In vitro studies exploiting ventricular cardiomyocytes that harbour DSP loss and concurrent early connexin loss phenocopied the loss of beat-to-beat regulation observed in DSP csKO mice and atria, extending the importance of DSP-associated mechanisms in driving beat-to-beat regulation of working cardiomyocytes. CONCLUSION We provide evidence of a mechanism that implicates an essential role for desmosomes in cardiac pacemaker function, which has broad implications in better understanding mechanisms underlying beat-to-beat regulation as well as sinus node disease and dysfunction.
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Affiliation(s)
- Valeria Mezzano
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613C, USA
| | - Yan Liang
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613C, USA
| | - Adam T Wright
- Department of Bioengineering, University of California-San Diego, La Jolla, CA 92093, USA
| | - Robert C Lyon
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613C, USA
| | - Emily Pfeiffer
- Department of Bioengineering, University of California-San Diego, La Jolla, CA 92093, USA
| | - Michael Y Song
- Scripps Translational Science Institute, Department of Medicine, Scripps Green Hospital, La Jolla, CA 92037, USA
| | - Yusu Gu
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613C, USA
| | - Nancy D Dalton
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613C, USA
| | - Melvin Scheinman
- Department of Cardiac Electrophysiology, University of California-San Francisco, San Francisco, CA 94143, USA
| | - Kirk L Peterson
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613C, USA
| | - Sylvia M Evans
- Skaggs School of Pharmacy, University of California-San Diego, La Jolla, CA 92093, USA
| | - Steven Fowler
- Cardiovascular Genetics Program, New York University School of Medicine, New York, NY 10016, USA
| | - Marina Cerrone
- Cardiovascular Genetics Program, New York University School of Medicine, New York, NY 10016, USA
| | - Andrew D McCulloch
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613C, USA Department of Bioengineering, University of California-San Diego, La Jolla, CA 92093, USA
| | - Farah Sheikh
- Department of Medicine, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0613C, USA
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Ito H, Badhwar N, Kawamura M, Vedantham V, Tseng Z, Lee B, Lee R, Marcus G, Gerstenfeld E, Scheinman M. POST-SHOCK ELECTROMECHANICAL DISSOCIATION DURING DEFIBRILLATION THRESHOLD TESTING. J Am Coll Cardiol 2016. [DOI: 10.1016/s0735-1097(16)30784-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Brugada syndrome might stay undetected in patients until surviving cardiac arrest. Despite the prominent advances in exploring the disease in the past 2 decades, many questions remain unanswered and the controversies continue. Despite all mutations identified to be associated with the disease, two-thirds of cases have a negative genetic test. Future studies should be more directed on modulating factors and their impact on patients' risk for sudden death to help physicians in risk stratifying their patients and optimally implementing an implantable cardioverter defibrillator to prevent sudden cardiac death.
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Affiliation(s)
- Marwan M Refaat
- Cardiac Electrophysiology, Cardiology, Department of Internal Medicine, American University of Beirut Faculty of Medicine and Medical Center, 3 Dag Hammarskjold Plaza, 8th Floor, New York, NY 10017, USA; Department of Biochemistry and Molecular Genetics, American University of Beirut Faculty of Medicine and Medical Center, 3 Dag Hammarskjold Plaza, 8th Floor, New York, NY 10017, USA; Department of Biochemistry and Molecular Genetics, American University of Beirut Medical Center, Beirut, Lebanon; Cardiology Division, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
| | - Mostafa Hotait
- Cardiology Division, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Melvin Scheinman
- Division of Cardiology, Department of Medicine, University of California San Francisco Medical Center, San Francisco, CA, USA
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47
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Scheinman M. Challenging Cases, Match Wits with the Masters. Card Electrophysiol Clin 2016; 8:xxi. [PMID: 26920204 DOI: 10.1016/j.ccep.2015.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Melvin Scheinman
- University of California San Francisco Medical Center, San Francisco, 500 Parnassus Avenue, MUE 436, San Francisco, CA 94143-1354, USA.
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48
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Refaat MM, El Hage L, Steffensen AB, Hotait M, Schmitt N, Scheinman M, Badhwar N. Iron Overload Leading to Torsades de Pointes in β-Thalassemia and Long QT Syndrome. Card Electrophysiol Clin 2016; 8:247-256. [PMID: 26920202 DOI: 10.1016/j.ccep.2015.10.037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The authors present a unique case of torsades de pointes in a β-thalassemia patient with early iron overload in the absence of any structural abnormalities as seen in hemochromatosis. Genetic testing showed a novel KCNQ1 gene mutation 1591C>T [Gln531Ter(X)]. Testing of the gene mutation in Xenopus laevis oocytes showed loss of function of the IKs current. The authors hypothesize that iron overload combined with the KCNQ1 gene mutation leads to prolongation of QTc and torsades de pointes.
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Affiliation(s)
- Marwan M Refaat
- Cardiology Division, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon; Department of Biochemistry and Molecular Genetics, American University of Beirut Medical Center, Beirut, Lebanon; Cardiac Electrophysiology, Cardiology, Department of Internal Medicine, American University of Beirut Faculty of Medicine and Medical Center, 3 Dag Hammarskjold Plaza, 8th Floor, New York, NY 10017, USA; Department of Biochemistry and Molecular Genetics, American University of Beirut Faculty of Medicine and Medical Center, 3 Dag Hammarskjold Plaza, 8th Floor, New York, NY 10017, USA
| | - Lea El Hage
- Division of Cardiology, Department of Medicine, University of California San Francisco Medical Center, 500 Parnassus Avenue, MUE-431, San Francisco, CA 94143-1354, USA
| | - Annette Buur Steffensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Mostafa Hotait
- Cardiology Division, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon
| | - Nicole Schmitt
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Melvin Scheinman
- Division of Cardiology, Department of Medicine, University of California San Francisco Medical Center, 500 Parnassus Avenue, MUE-431, San Francisco, CA 94143-1354, USA
| | - Nitish Badhwar
- Division of Cardiology, Department of Medicine, University of California San Francisco Medical Center, 500 Parnassus Avenue, MUE-431, San Francisco, CA 94143-1354, USA.
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49
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Refaat MM, Scheinman M, Badhwar N. Narrow Complex Tachycardia: What is the Mechanism? Card Electrophysiol Clin 2016; 8:67-9. [PMID: 26920172 DOI: 10.1016/j.ccep.2015.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This article presents a diagnostic dilemma in which atrioventricular nodal reentrant tachycardia (AVNRT) and junctional tachycardia (JT) were differentiated based on tachycardia initiation with atrial extrastimulus as well as on the response to progressive decremental atrial extrastimuli. The progressive increase in A2H2' and H2H2' in response to atrial extrastimuli favors reentry as the mechanism of the tachycardia. This is a novel mechanistic differentiation of AVNRT from focal JT.
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Affiliation(s)
- Marwan M Refaat
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Faculty of Medicine and Medical Center, American University of Beirut, PO Box 11-0236, Riad El-Solh, Beirut 1107 2020, Lebanon.
| | - Melvin Scheinman
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, University of California, 500 Parnassus Avenue, San Francisco, CA 94143, USA
| | - Nitish Badhwar
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, University of California, 500 Parnassus Avenue, San Francisco, CA 94143, USA
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50
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Abstract
Arrhythmogenic right ventricular cardiomyopathy is an inherited disorder characterised by progressive replacement of ventricular myocardium by fibrofatty tissue that predisposes patients to ventricular arrhythmias, heart failure and sudden death. Treatment focuses on slowing disease progression, decreasing the burden of arrhythmias and preventing sudden cardiac death through placement of implantable cardioverter-defibrillators (ICDs), catheter ablation and the use of antiarrhythmic medication. Although only ICDs have been demonstrated to affect patient mortality, antiarrhythmic medications are important adjuncts in reducing patient morbidity and inappropriate ICD therapy. Of the individual antiarrhythmic agents available, sotalol, beta-blockers and amiodarone appear to be most effective in arrhythmia suppression. Calcium-channel blockers may be effective in selected patients. For patients who are refractory to single agent therapy, combination therapy may be considered with the most effective combinations being sotalol + flecainide and amiodarone + beta-blockers.
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Affiliation(s)
- Simon Ermakov
- Stanford University Hospital and Clinics, California, US
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