Atrial vs. dual-chamber cardiac pacing in sinus node disease: a register-based cohort study.

AIMS In patients with sinus node disease, dual-chamber pacing (DDD) possibly results in adverse effects on the ventricular function. We have compared the incidence of cardiovascular morbidity and mortality in patients with sinus node disease and with atrioventricular (AV) synchronous pacemakers, DDD vs. atrial pacing (AAI). METHODS AND RESULTS A nation-wide population-based cohort of 8777 patients with AAI- or DDD-mode pacemakers was followed during 12 years. The cohort was linked to national healthcare and census registers. Patients with DDD pacing and without any pre-implant admission for atrial fibrillation or flutter had an increased risk of post-implant fibrillation or flutter, in relation to corresponding AAA patients [hazard ratio (HR) = 1.30; 95% confidence interval (CI) 1.10-1.52]. A slight increase in the risk of any cardiovascular disease (HR = 1.07; CI, 1.00-1.15), and all-cause mortality (HR = 1.12; CI, 1.00-1.25), was seen among DDD patients, in relation to AAI patients, but there was no significant difference in the risk of ischaemic or unspecified stroke (HR = 1.14; CI, 0.94-1.37). Among DDD patients, the all-cause mortality did not differ from the general population [standardized mortality ratio (SMR) = 1.04; CI, 0.98-1.11]. Patients with AAI, however, had a decreased all-cause mortality risk (SMR = 0.89; CI, 0.82-0.97). CONCLUSION Our results support AAI as the preferred mode of pacing in patients with sinus node disease, and a normal AV node function.