Long term performance of dual chamber pacemakers

Records of 98 patients who had dual chamber pacemakers implanted at our institution and had a follow up for at least 6 months (range 6-90 months, mean 47.8 months) were analysed for long term performance of the pacemakers. There were 78 males and 20 females in the age range of 14 to 81 (mean 51.1 +/- 13.6) years. The mode of pacing was VDD in 12, DVI in 9 and DDD in 77 patients. Atrial malsensing was seen in 15 (16.7%) cases and generally occurred within the first week of implantation. Atrial lead dislodgement occurred in 4 cases (4.1%). Most of the problems related to atrial lead could be managed conservatively and re-operation was performed in only 4 cases. Other problems encountered on follow up included cross talk in one, endless loop tachycardia in 4, and pulse generator pocket erosion or infection in 4 (4.1%) patients. There were two instances of ventricular undersensing and one instance of insulation failure in the ventricular lead. A total of 16 patients underwent elective replacement of pulse generator 53-84 months (mean 66.3) following the initial implants. It is concluded that the incidence of pacemaker malfunction and other problems with dual chamber pacemaker implantation are not high; and most cases can be managed by conservative measures such as reprogramming.