BACKGROUND: Between January 1985 and June 1995, more than 1800 consecutive patients underwent implantation of a new permanent cardiac pacemaker at our institution. Thirty-six patients (0.02%) had 45 reinterventions for infected pacemaker systems. METHODS: in group A, 24 of 27 patients received simultaneous implantation of a new pacemaker. One had reimplantation of the same pacemaker in the same pocket, and two did not require reimplantation. The leads were retained in 19 (70%) of the patients. In group B, nine patients underwent cardiopulmonary bypass or "pursestring" surgery for removal of an infected pacemaker; a new epicardial pacemaker system was simultaneously implanted in seven patients. RESULTS: Identification of an infectious agent failed in 17 patients (47%), and Staphylococci were found in 15 patients (42%). The time from pacemaker implantation to onset of infection ranged from 1 month to 11 years (mean 31 months; median 19 months) and the time from onset of infection to surgical treatment from 1 month to 7 years (mean 7 months; median 2 months). The mean follow-up time is 74 months (range, 1 month to 10 years; median 5 years). There were 9 reoperations in 3 patients (16%) of group A for recurrent infection of their retained leads ultimately necessitating the use of open cardiac surgery. There was no early death; six patients died late due to unrelated causes. CONCLUSIONS: Complete removal of all pacemaker leads is recommended; open heart surgery with the use of cardiopulmonary bypass is indicated in selected cases and is effective and safe.