Predictors of first discharge and subsequent survival in patients with automatic implantable cardioverter-defibrillators

Background. Two hundred eighteen patients were evaluated in a two-phase approach (time to first appropriate discharge, survival after discharge) to identify factors that may be related to maximal benefit derived from use of an automatic implantable cardioverter-defibrillator (AICD). Methods and Results. One hundred ninety-seven patients survived implantation of AICD, with or without concomitant cardiac surgery. One hundred five patients had an AICD discharge associated with syncope, presyncope, documented sustained ventricular tachycardia or fibrillation, or sleep at 9.1±11.1 months after implantation. Patients survived 23.8+18.0 months after AICD discharge. Left ventricular dysfunction (p=0.008 for ejection fraction less than 25%) was associated with earlier AICD discharge and shortened survival after AICD discharge (p=0.008 for ejection fraction less than 25%; p=0.01 for New York Heart Association functional class III and IV). β-Blocker administration (p=0.006) and coronary bypass surgery (p=0.06) were associated with later AICD discharge. Coronary bypass surgery (p=0.035) but not β-blockers was associated with more prolonged survival after AICD discharge. Conclusions. These data suggest that a relatively easy algorithm can be applied to predict which patient will benefit most from AICD implantation.