Permanent ventricular and dual chamber cardiac stimulation: role of pacingmode in relation to chronic atrial fibrillation risk and stroke development

Ventricular single chamber permanent cardiac pacing undoubtedly eliminates symptoms related to extremely low cardiac rate, but also contributes to inc reased morbidity due to onset of permanent atrial fibrillation (PAF). Many studies have shown the superiority of atrial and dual chamber cardiac pacin g in reducing atrial fibrillation risk and in preventing correlated embolic complications. It is not known, however, if this advantage is maintained i n the elderly and in particular in the oldest old people. From 1986 onwards , we analyzed 690 chronically paced patients, 472 received a single chamber ventricular pacemaker (VP), while 218 received a dual chamber pacemaker (D P). All patients underwent regular controls every 6 months. End points of t he study were the onset of atrial fibrillation, embolic events and death. L ife table analysis of the incidence of all the events during a follow-up of 120 months was carried out, distinguishing two groups (VP and DP) homogene ous in mean age and type of cardiopathy. The total incidence of PAF was 51. 4% in the VP and 11.4% in the DP group (P < 0.05). After 7 years from impla nt, PAF was present in 90% of VP and 20% of DP patients (P < 0.001). We fou nd a significantly higher occurrence of cerebral ischemic events (stroke or transient ischemic attacks) in the VP group (P < 0.05). Even if no great d ifference in mortality was found between the two groups, a significant redu ction of cardiovascular mortality associated with DP has been observed in t he subgroup of patients with sick sinus syndrome. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.