Sudden death in idiopathic dilated cardiomyopathy: role of ventricular arrhythmias.

Sudden cardiac death (SCD) is associated with idiopathic congestive cardiomyopathy (IDCM) and most commonly is due to ventricular tachyarrhythmias. The recurrence rate of SCD in the absence of specific therapy is thought to be around 20%-30% per year. Asymptomatic and symptomatic ventricular arrhythmias are common in patients with IDCM and the direct causal link of such arrhythmias with SCD in IDCM patients remains to be established. Furthermore, therapy directed at suppressing these ventricular arrhythmias has not been shown to decrease the incidence of SCD. Various approaches such as ambulatory monitoring, electrophysiological testing, signal-averaged electrocardiogram, and hemodynamics have met with variable success in identifying patients prone to SCD. Additionally, therapeutic approaches to prevent SCD in IDCM patients have produced equivocal results. This article reviews the published studies addressing the causal link of ventricular arrhythmias to sudden death in patients with IDCM and the attempts to decrease the incidence of sudden.