The efficacy of implantable cardioverter-defibrillators in heart transplant recipients: results from a multicenter registry.

BACKGROUND Sudden cardiac death among orthotopic heart transplant recipients is an important mechanism of death after cardiac transplantation. The role for implantable cardioverter-defibrillators (ICDs) in this population is not well established. This study sought to determine whether ICDs are effective in preventing sudden cardiac death in high-risk heart transplant recipients. METHODS AND RESULTS We retrospectively analyzed the records of all orthotopic heart transplant patients who had ICD implantation between January 1995 and December 2005 at 5 heart transplant centers. Thirty-six patients were considered high risk for sudden cardiac death. The mean age at orthotopic heart transplant was 44+/-14 years, the majority being male (n=29). The mean age at ICD implantation was 52+/-14 years, whereas the average time from orthotopic heart transplant to ICD implant was 8 years +/-6 years. The main indications for ICD implantation were severe allograft vasculopathy (n=12), unexplained syncope (n=9), history of cardiac arrest (n=8), and severe left ventricular dysfunction (n=7). Twenty-two shocks were delivered to 10 patients (28%), of whom 8 (80%) received 12 appropriate shocks for either rapid ventricular tachycardia or ventricular fibrillation. The shocks were effective in terminating the ventricular arrhythmias in all cases. Three (8%) patients received 10 inappropriate shocks. Underlying allograft vasculopathy was present in 100% (8 of 8) of patients who received appropriate ICD therapy. CONCLUSIONS Use of ICDs after heart transplantation may be appropriate in selected high-risk patients. Further studies are needed to establish an appropriate prevention strategy in this population.