The automatic internal cardioverter defibrillator (AICD) is effective in preventing death in patients with malignant ventricular arrhythmias (VT/VF) refractory to medical therapy. Because of the long waiting period for heart transplantation and the high likelihood of sudden arrhythmic death in this population, this study was undertaken to assess the value of the AICD in patients awaiting heart transplantation who have refractory VT/VF. Fourteen patients awaiting heart transplantation who had a history of VT/VF underwent AICD implantation (10 extrapericardial and four intrapericardial) via median sternotomy. All patients survived the AICD implantation and have either had heart transplantation or await transplantation at present (1 to 24 months after AICD implantation). Twelve of these patients have received a mean of 10 AICD shocks (range, 0 to 32). One patient received 19 shocks in the 24-hour period before transplantation. Two patients have died of progressive heart failure. Five patients have gone on to successful transplantation, and seven patients await heart transplantation with a functioning AICD in place. In conclusion, the AICD represents a new "bridge" to heart transplantation that is well tolerated by these high-risk patients, avoids drug side effects, and is efficacious in aborting sudden death, thereby allowing them to undergo successful heart transplantation.