We report our experience with dual chamber pacemakers in 70 patients (mean age 64.5), of whom 42 had AV block and 28 sick sinus syndrome, nine of them associated with AV block. Other cardiac disease coexistent with the conduction disturbance was present in 57% of the patients. Follow-up was conducted after implantation at first, 3rd, 6th month, and thereafter each 6 months. Mean follow-up was 20 +/- 14.3 months (2-72); of the 70 patients, 88% and 73% were followed at least for 6 and 12 months, respectively. Six patients (five had AV block) died 17 months on average after implantation. All patients but one had concomitant cardiac disease. Eleven patients (15.6%) presented complications, being all of them related to atrial channel: reprogramming to VVI in five (7%), mainly due to chronic atrial fibrillation (4 patients), whereas in the other one was secondary to loss of pacing and sensing functions; acute dislocation corrected with reoperation in 3 patients (4.3%); temporary loss of atrial sensing in 2 patients, and chronic in the last one, with change to DVI mode. Overall, considering deaths and changes to VVI mode, 15.6% of patients were not be able to maintain dual chamber pacing. In conclusion, our results show: 1) low rate of major complications; 2) good outcome of patients suffering from sick sinus syndrome; 3) the development of chronic atrial fibrillation was the main limitation of DDD pacing system.