Amiodarone versus Implantable Defibrillator (AMIOVIRT): background, rationale, design, methods, results and implications.

Non ischemic dilated cardiomyopathy (NIDCM) is a substrate for sudden cardiac death. Treatment with amiodarone may have a positive or neutral survival benefit. The role of ICD therapy in the primary prevention of sudden cardiac death in asymptomatic NIDCM patients is not clear. The purpose of the Amiodarone versus Implantable Defibrillator (AMIOVIRT) study was to compare total mortality, arrhythmia-free survival, quality of life and costs of therapy in patients with NIDCM, asymptomatic non-sustained ventricular tachycardia (NSVT) and left ventricular ejection fraction <or=0.35 who were randomized to therapy with amiodarone (52 patients) or an ICD (51 patients). At the first scheduled interim analysis, the previously determined stopping rule for futility was reached and the study was stopped. There was no statistically significant difference in the 1- and 3-year survival rates in the patients who received amiodarone compared with those who received an ICD (90% and 87% for amiodarone group versus 96% and 88% for ICD group; p = 0.8). There was a trend towards improved arrhythmia-free survival rates (p = 0.1), and cost of medical care (8,879 dollars vs. 22,039 dollars, p = 0.1) in the patients who were treated with amiodarone as compared to the patients who were treated with an ICD. At one year, the quality of life measures were not significantly different (p = 0.1).