Sudden cardiac arrest continues to be a major public health challenge. Nearly 20% of all mortality in industrialized countries is due to sudden cardiac arrest. This is of epidemic proportion and remains a daunting problem. The actual incidence of sudden cardiac death is highly variable but recent prospective studies using multiple sources in the United States, Europe, and China have estimated sudden death rates ranging from 50 to 100 per one hundred thousand people in the general population. Despite the reduction in overall coronary heart disease mortality in the past thirty years, sudden cardiac death has not declined to a similar extent suggesting the percentage of deaths that are due to sudden cardiac arrest has remained fixed or actually increased as a percent of the total mortality. More than 50% of all coronary heart disease deaths are caused by sudden cardiac arrest. The exact nature of that sudden cardiac death has changed somewhat over the past two decades. While a vast majority of sudden cardiac arrest victims were felt to be due to ventricular tachycardia or fibrillation two decades ago, recent data suggests the percentage of people dying of ventricular tachycardia/fibrillation has decreased and incidence of sudden death associated with bradyarrhythmias has increased. This is probably an expression of an aging population within an increasing incidence of heart failure which demonstrates an inverse relationship to the degree of heart failure with the incidence of sudden cardiac death. Obviously death associated with end-stage heart failure is not going to be mitigated by wide spread implantation of an implantable defibrillator.