Implantable cardioverter defibrillator: use in patients with no symptoms and at high risk

Twenty-seven patients with asymptomatic, nonsustained ventricular tachycardia whose evaluation suggested they were at high risk for sustained ventricular arrhythmias were treated with implantable cardioverter defibrillators. The option of conventional therapy (including the option of no therapy) was presented to each patient and rejected in favor of defibrillator implantation on an experimental basis. Eighteen patients had coronary artery disease and inducible sustained ventricular tachycardia, 8 had idiopathic dilated cardiomyopathy, and 1 had hypertrophic cardiomyopathy and a strong family history of sudden cardiac death. The mean ejection fraction was 27% +/- 10%. Operative morbidity (3%) and mortality (3%) were low. Mean overall survival was 92% and 88% at 1 and 2 years, respectively. Sixteen (59%) of the 27 patients had appropriate defibrillator discharges during a mean follow-up of 35 +/- 15 months. The mean time to first appropriate discharge was 18 +/- 17 months, and mean follow-up after first discharge was 17 +/- 20 months. In conclusion, implantable cardioverter defibrillator placement in high-risk patients without symptoms is a feasible approach that may have resulted in benefit in selected patients. Large-scale randomized trials currently under way will determine the risk/benefit ratio of this management approach.