Clinical role of antiarrhythmic drugs in the prevention of sudden death

Sudden cardiac death is a leading cause of mortality in the United States, but recent studies suggest that its annual incidence is declining. The annual incidence of sudden cardiac death is about 0.55 per 1000 people in North America, accounting for more than 160,000 deaths each year in the United States.1 In Seattle, there was a 34% decrease in the annual incidence of out-of-hospital cardiac arrest and a 56% decrease in ventricular fibrillation (VF) as the first identified rhythm between 1980 and 2000.2 This trend corresponds with the declining incidence of cardiovascular disease in this country in the past two decades.1 Holter monitoring has revealed that more than 75% of sudden cardiac deaths are due to ventricular tachycardia (VT) or VF.3 A large majority of these patients have underlying structural heart disease including dilated and hypertrophic cardiomyopathies and ischemic heart disease.