ITALIAN MULTICENTER CLINICAL-EXPERIENCE WITH ENDOCARDIAL DEFIBRILLATION - ACUTE AND LONG-TERM RESULTS IN 307 PATIENTS

This study presents the acute and long-term results of 307 patients (267 men, mean age 57.5 years, 205 suffering from coronary artery disease, mean left ventricular ejection fraction 33.3%) with malignant Ventricular tachyarrhythmias who underwent attempted transvenous ICD implantation with the CPI Endotak lead system in 37 Italian centers. Transvenous ICD implantation was ultimately accomplished in 306 (99.7%) patients. These included 19 subjects with high (< 10 J below output energy of implanted device) defibrillation threshold (DFT) at implant. One hundred sixty-four patients (53%) were implanted with the endocardial lead alone, while 142 also received an SQ patch or SQ array. The mean DFT (not always step-down DFT) at implant was 16.9 +/- 5.7 joules; 15.3 +/- 5.2 joules with biphasic shock and 19.6 +/- 5.4 joules with monophasic shock; P < 0.0001. A significantly higher percentage of patients rested with a biphasic shock could be implanted with adequate safety margin and without an additional SQ patch or SQ array (98% and 81%, respectively). No perioperative deaths occurred. During the mean follow-up of 14.5 +/- 10.2 months, 140 patients (52%) received at least one appropriate shock. An inappropriate shock was observed in 26% of episodes. The 1- and 3-year actuarial incidence of sudden death was 2% and 4%, respectively, and that of total death was 10% and 20%, respectively. A pocket infection requiring ICD explantation occurred in 4 patients (1.4%) and an endocardial lead dislodgment in 11 patients (3.6%). Two patients (0.3%) showed a sensing pin disconnection and six patients (2.3%) had a lead insulation break. The results of this Italian multicenter trial indicate that the CPI Endotak lead system is (I simple, safe, and reliable system for endocardial defibrillation. When compared to epicardial leads, it clearly reduces the perioperative mortality and morbidity, while maintaining a similar efficacy in preventing sudden death and terminating ventricular arrhythmias.