Comparative survival after permanent ventricular and dual chamber pacing for patients with chronic high degree atrioventricular block with and without preexistent congestive heart failure

To determine whether survival after permanent ventricular demand (VVI) pacing differs from survival after permanent dual chamber (DVI or DDD) pacing in patients with chronic high degree atrioventricular (AV) block (Mobitz type II or trifascicular block), 132 patients who received a VVI pacemaker (Group 1) and 48 patients who received a DVI or DDD pacemaker (Group 2) were followed up for 1 to 5 years. There was no significant difference in sex distribution, mean age or incidence of coronary heart disease, hypertension, valvular heart disease, diabetes mellitus, stroke or renal failure between Groups 1 and 2.Overall, the predicted cumulative survival rate at 1, 3 and 5 years was 89, 76 and 73%, respectively, for Group 1 and 95, 82 and 70%, respectively, for Group 2. In patients with preexistent congestive heart failure, the predicted cumulative survival rate at 1, 3 and 5 years was 85,66 and 47%, respectively, for Group 1 (n = 53) and 94, 81 and 69%, respectively, for Group 2 (n = 20). The 5 year predicted cumulative survival rate was significantly lower in Group 1 patients with preexistent congestive heart failure than in Group 2 patients with the same condition (p < 0.02). There was no significant difference in 5 year cumulative survival rate between Groups 1 and 2 for patients without preexistent congestive heart failure.The results suggest that permanent dual chamber pacing enhances survival to a greater extent than does permanent ventricular demand pacing in patients with high degree AV block and preexistent congestive heart failure