LEAD FRACTURE IN CEPHALIC VERSUS SUBCLAVIAN APPROACH WITH TRANSVENOUSIMPLANTABLE CARDIOVERTER-DEFIBRILLATOR SYSTEMS

Lead fracture, occurring in approximately 1%-4% of patients, is an inf requent, but potentially catastrophic complication of permanent pacing systems. Its incidence in transvenous defibrillator systems has not b een established. We analyzed data from 757 patients undergoing implant ation of transvenous cardioverter defibrillator systems using the Medt ronic Transvene Lead(R) system between October 20, 1989 and June 25, 1 992 to determine if site of venous approach influenced incidence of le ad fracture. All patients received a 3-lead system in 1 of 3 configura tions: (1) right ventricle/superior vena cava/subcutaneous patch; (2) right ventricle/coronary sinus/subcutaneous patch; or (3) right ventri cle/superior vena cava/coronary sinus. Of 767 right ventricular leads placed, 523 were placed via the subclavian vein, 221 via cephalic vein , and 18 via the infernal jugular (5 leads were implanted using anothe r vein). The total number of leads is greater than the total number of patients, as five patients received a second defibrillator system if the initial system was explanted and reimplanted for any reason. Seven patients (0.9%) had right ventricular lead fracture, presenting with inappropriate defibrillator shocks (1), loss of pacing ability (3), bo th loss of pacing ability and inappropriate shocks (1), or increased p acing threshold (2). All patients required reoperation. All had leads placed by the subclavian venous approach, with chest X ray confirming fracture at the clavicle-first rib junction in 6 of 7 cases. Using Fis her's Exact test, the difference in lead fracture between subclavian a nd cephalic vein implant approached statistical significance (P = 0.08 ). The trend toward increased lead fracture incidence with leads place d via subclavian vein suggests that cephalic vein approach may be pref erable to avoid this complication.