IMPLANTATION OF TRANSVENOUS NONTHORACOTOMY CARDIOVERTER-DEFIBRILLATORSYSTEMS IN PATIENTS WITH PERMANENT ENDOCARDIAL PACEMAKERS

Among 177 patients in whom a nonthoracotomy approach was initially use d to implant a cardioverter-defibrillator system, 11 (6%) patients als o received a separately implanted permanent pacemaker. The main proble m encountered in these patients were previously implanted unipolar pac emakers (n = 3) and ventricular pacing leads positioned at the right v entricular apex, the latter interfering with optimal placement of the tripolar implantable cardioverter-defibrillator (ICD) lead (n = 9). Th e approaches used to solve these problems were individualized and incl uded placemen of the ICD sensing lead at the right ventricular outflow tract (n = 3), initial placement (n = 1) or subsequent repositioning (n = 2) of the right ventricular pacing lead at the outflow tract, upg rade from unipolar to bipolar systems (n = 2), reprogramming from the DDD to AAI mode (n = 2), inactivation of the pacemaker (n = 1), and si multaneous placement of a single-chamber atrial pacemaker with the ICD lead (n = 2). These revisions fulfilled the pacing needs in each pati ent and prevented unfavorable sensing interaction between the two syst ems.