[Initial clinical results with a novel implantable cardioverter-defibrillator: a prospective evaluation in 3 Swiss university hospitals].

The most important technical improvements of implantable cardioverter-defibrillators (ICD) of the latest generation comprise more sophisticated antitachycardia pacing options, stored intracardiac electrograms and biphasic shock capabilities which virtually always allow ICD implantation without thoracotomy. The present study summarizes the first clinical experience with these new devices. In 37 consecutive symptomatic (near sudden death 17, syncope 16, pre-syncope 4) patients aged 56 +/- 10 years with refractory ventricular arrhythmias (presenting arrhythmia: ventricular fibrillation 14, ventricular tachycardia 22, not documented 1), an ICD (Jewel PCD 7219, Medtronic) was implanted. Coronary artery disease was present in 21, dilated cardiomyopathy in 5, valvular heart disease in 2 and various conditions in 8 patients; the mean left ventricular ejection fraction was 43 +/- 18%. In 29 patients (78%), the ICD was inserted in a pectoral and in 8 (22%) in an abdominal position. A non-thoracotomy lead (NTL) configuration was successfully implanted in 36/37 patients (97%) (purely transvenous systems in 30, in combination with subcutaneous patch electrode in 6). Surgical complications comprised one pneumothorax, one hemorrhage and one death due to sepsis; during a mean follow-up of 5 +/- 3 months, another patient died of heart failure and 2 revisions (5.4%) for lead problems (1 connector, 1 SQ-patch) became necessary. In 23/37 patients (62%), the ICD was activated after 74 +/- 89 days post implant. 22 of these 23 patients (96%) received one or more appropriate shocks (9 +/- 22 shocks per patient). The actuarial survival was 95% at 6 months. In the present study, an ICD of the newest generation was successfully implanted without thoracotomy in > or = 97% and with purely transvenous systems in > or = 84%. Compared to older systems, this has made the implantation procedure remarkably easier and will most likely lead to a further reduction in mortality and morbidity. Despite the relatively short follow-up, the high incidence of appropriate ICD utilization underscores the high recurrence rate of arrhythmias in this population and suggests that the ICD may be very effective in preventing unnecessary rehospitalizations.