SURGICAL EXPERIENCE WITH DEFIBRILLATOR NONTHORACOTOMY LEAD SYSTEMS

Over a 3 year period, 140 patients underwent attempted implanation of an automatic cardioverter/defibrillator using the nonthoracotomy lead (NTL) system. Indications included sustained monomorphic ventricular ( VT) (84), nonsustained (VT) with poor ventricular function (7), ventri cular fibrillation (VF) (31), VT/VF (16), and familial long QT syndrom e (2). A total of 115 males and 25 females comprised the group; mean a ge was 57 +/- 14 years; 59% had previous coronary bypass and/or valve surgery. Mean left ventricular ejection fraction was 31 +/- 14%, cardi ac index was 2.4+/-1 L/m2, and systolic pulmonary artery pressure was 42+/-15 mm Hg. Under general anesthesia the NTL was introduced through the left subclavian vein. The subcutaneous patch and generator were p laced posteriorly on the serratus muscle and left upper quadrant, resp ectively. The length of the procedure was 117 +/- 46 minutes, and the mean number of defibrillation shocks for a successful implant was 9 +/ - 4. A total of 110 patients (79%) had successful implantations. Failu res were caused by a high defibrillation threshold (27) and the inabil ity to place the right ventricular lead (3). Predictors of failure inc luded preoperative antiarrhythmic drugs and cardiac index less-than-or -equal-to 1.8 +/- 4. Only 3 patients (2.0%) died postoperatively, from heart failure (2) and chronic heart transplant rejection (1). migrati on or dislodgement (8), infection (1), and hematoma (4). In summary, t he NTL system provides an alternative to epicardial systems in patient s requiring cardioverter/defibrillator implantation.