This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Merino, J. L. Articles by Duboc, D. Search for Related Content PubMed PubMed Citation Articles by Merino, J. L. Articles by Duboc, D. Related Collections Electrophysiology Clinical genetics Myocardial cardiomyopathy disease Ablation/ICD/surgery

(Circulation. 2000;101:e73.)
© 2000 American Heart Association, Inc.

Circulation Electronic Pages

Sudden Death in Myotonic Dystrophy: The Potential Role of Bundle-Branch Reentry

Jose L. Merino, MD; Rafael Peinado, MD; Jose A. Sobrino, MD

Hospital General Universitario La Paz, Madrid, Spain

	Introduction

 
To the Editor:

We read with interest the recent report of Lazarus et al.¹ This is an important study addressing the prevalence of His-Purkinje conduction disturbances and ventricular arrhythmia inducibility by a standard pacing protocol in a large sample of patients with myotonic dystrophy (MD) and asymptomatic conduction abnormalities. However, several points of the discussion should be reviewed owing to possible misinterpretation.

First, the authors found a high frequency of prolonged HV interval and raised the issue of prophylactic pacing to limit the high incidence of sudden death seen in MD. However, reports of sudden death in patients with MD after pacemaker implantation (including 1 patient in the present study) and of sudden death shortly after clinical documentation of sustained monomorphic ventricular tachycardia (VT)² make VT in MD a potential cause of sudden death likely enough to reconsider the authors’ insinuation of prophylactic pacemaker implantation. Furthermore, demonstration of HV-interval prolongation should not be taken only as a risk factor of AV block, because VT in MD typically has a bundle-branch reentrant mechanism,³ a mechanism that is associated with slow conduction in the His-Purkinje system.

Second, the authors reported a higher inducibility of polymorphic ventricular arrhythmias in younger patients than in older patients, speculating that evolution to sudden death of patients with positive inducibility in the former group could account for the lower inducibility in the latter group. However, inducibility of polymorphic ventricular arrhythmias is often considered nonspecific, especially if induced with aggressive ventricular stimulation, as in the present study (200-ms . . . [Full Text of this Article]

A. Lazarus, MD; J. Varin, MD; Z. Ounnoughene, MD; H. Radvanyi, MD; C. Junien, PharmD, PhD; J. Coste, MD; P. Laforet, MD; B. Eymard, MD; H.M. Becane, MD; S. Weber, MD; D. Duboc, MD

Service de Cardiologie, Hôpital Cochin, Paris, France