FIRST EXPERIENCE WITH A NEW NONTHORACOTOMY DEFIBRILLATION LEAD SYSTEM

The clinical efficacy and safety of a new nonthoracotomy defibrillatio n lead system (TVL lead system, Ventritex, Inc., Sunnyvale, Calif.) wa s studied in patients with Ventricular tachycardia or fibrillation. Im plantation of the TVL lead system and a Cadence pulse generator (Ventr itex, Inc.) was attempted in 27 patients. A subcutaneous patch lead wa s added if required to achieve adequate defibrillation energy. Patient s were monitored for an average of 6 +/- 4 months (range 1 week to 14 months). Implantation was successful in 26 patients (96%). Twenty-thre e of those patients (88%) were implanted in a lead-alone configuration ; the remaining three (12%) required a subcutaneous patch lead. The me an defibrillation threshold was 401 +/- 120 V (12 +/- 7 J) at implanta tion, 467 +/- 134 V (15 +/- 8 J) at predischarge testing, and 452 +/- 151 V (14 +/- 9 J) at 4-month follow-up. The mean defibrillation thres hold at 4 months was not significantly different from that at implant. No deaths, sensing anomalies, infections, lead fractures, or lead dis lodgments occurred. One patient required addition of a subcutaneous pa tch 4 months after device implantation because of an elevated defibril lation threshold. Eight patients (31%) experienced 545 spontaneous arr hythmic episodes, and all episodes were successfully terminated by the device. In conclusion, the TVL lead system combined with Cadence tier ed-therapy defibrillator has a high success rate and low complication rate, and it can be recommended for treatment of patients with life-th reatening ventricular tachyarrhythmias.