TRANSVENOUS DEFIBRILLATOR SYSTEMS IMPLANTED BY ELECTROPHYSIOLOGISTS IN THE CATHETERIZATION LABORATORY

Background: A significantly lower perioperative mortality has establis hed the nonthoracotomy approach as the preferred technique in implanta ble cardioverter defibrillation (ICD) implantation. With the currently available transvenous endocardial leads in combination with the expan ded use of biphasic ICD devices, the need for use of an additional sub cutaneous lead has almost been eliminated. Thus, implantation of these systems has been simplified and reports have appeared in the literatu re that the procedure can now be performed by an electrophysiologist a lone without surgical assistance in the electrophysiology or catheteri zation laboratory. Hypothesis: The purpose of this study was to invest igate the feasibility and safety of ICD implantation by an electrophys iologist in a procedure performed entirely in the catheterization labo ratory without the assistance of a surgeon.Methods: Over a period of 2 8 months, we implanted transvenous ICDs in 40 consecutive patients wit h (n = 34) and without (n = 6) use of general anesthesia in the cathet erization laboratory with minor surgical assistance in abdominal pocke t fashioning for the first two cases and then working alone for the re mainder. The study included 36 men and 4 women, aged 59 +/- 12.5 years , with coronary artery (n = 22) or valvular heart disease (n = 4), car diomyopathy (n = 12), and long QT syndrome (n = 1) or idiopathic ventr icular tachycardia (n = 1), and a mean left ventricular ejection fract ion of 34%, who presented with ventricular tachycardia (n = 30) or ven tricular fibrillation (n = 10). Results: One-lead ICD systems (Endotak (R), n = 21; Tansvene(R), n = 8; or EnGuard(R), n = 1) were used in 30 patients, and 2-lead (EnGuard, n = 5 or Transvene, n = 5) systems in 10 patients. Generators were implanted in an abdominal (n = 17) or pec toral (n = 23) pocket. Active can devices were employed in 17 patients . The defibrillation threshold averaged 9 J. All implants were entirel y transvenous with no subcutaneous patch. Biphasic ICD devices were em ployed in all pa tients. There were three complications (8%): one pulm onary edema that responded to drug therapy, one lead insulation break that required reoperation on the third day, and one pocket hematoma in a patient receiving anticoagulation, with no need for evacuation. The re were no operative deaths and no infections. After implant, patients were discharged at a mean of 3 days. All devices functioned well at p redischarge testing. During follow-up (12 +/- 8 months), 20 patients r eceived appropriate and 5 patients inappropriate shocks. Three patient s died of pump failure at 3, 7, and 19 months, respectively; they had received 0, 42, and 15 appropriate shocks, respectively, over these mo nths. Another patient succumbed to a myocardial infarction at 9 months . At 6 months, one patient developed subacute subclavian vein thrombos is which re solved with anticoagulation therapy. Conclusions: Current transvenous biphasic ICD systems allow experienced electrophysiologist s to implant them safely alone in the catheterization laboratory witho ut surgical assistance, even for abdominal implants, with a high succe ss rate and no need for use of a subcutaneous patch.