56-43: Importance of a monitoring zone in the diagnosis of arrhythmias in ICD carriers: retrospective evaluation of a long-term remote monitoring program

Abstract

Introduction: Implantable cardioverter-defibrillators (ICD) are the treatment of choice for primary prevention against sudden cardiac death across a broad spectrum of pathologies. ICD monitoring zones (MZ) allow passive features that do not interfere with functioning of active treatment zones. However, it is not well known whether programming MZ can affect the ICD arrhythmia redetection. The aim of the present study is to assess the relevance of MZ in clinical practice in a population undergoing ICD for primary prevention. Method(s): Retrospective analysis of patients (P) submitted to ICD or CRT-D implantation for primary prevention, followed with remote monitoring systems. MZ was analysed and recorded arrhythmias where assessed in detail. Result(s): 221P were studied (77% men; 64 +/- 12 years). Underlying pathologies were ischemic cardiomyopathy (42%), dilated cardiomyopathy (44%), hypertrophic cardiomyopathy (7%), primary electrical cardiac disease (5%), congenital heart disease (2%), and valvular heart disease (1%). Mean ejection fraction was 30 +/- 12%. The average follow-up period after implantation was 63 +/- 35 months. One hundred and seventy four MZ events were documented in 139P (62.9%): non-sustained ventricular tachycardia (NSV T)-74, supraventricular tachycardia-42, atrial ibrillation/atrial lutter-44, noise-5. Among the 137P who presented with arrhythmias in MZ (excluding 2P only with noise detection), 22P (16.1%) received appropriate shocks and/or antitachycardia pacing (ATP), whereas in the remaining 84P, 15.5% received appropriate ICD treatment (p = NS). In those P who presented with NSVT in MZ, 15P (20.5%) received appropriate shocks and/or ATP. In addition to the optimization of medical treatment, 3P underwent ablation of supraventricular arrhythmias detected in the MZ. Conclusion(s): Spontaneous ventricular and supraventricular arrhythmias are a common finding in ICD MZ. Programming this MZ is valuable in the diagnosis of arrhythmias and may be a useful feature in clinical practice.