Risk of atrial fibrillation after pacemaker implantation: A nationwide Danish registry-based follow-up study

Background: The overall risk of atrial fibrillation (AF) among patients with pacemaker (PM) in comparison to control cohort is unknown. Purpose: To investigate the risk of AF after implantation of a PM in an AF-naive population in comparison to an age- and sex-matched PM- and AF-free population cohort. Methods: All patients with a dual chamber PM (DDD) implanted between 2000 and 2014 without a known history of AF were included (n = 17,428). To compare, a general population cohort without pacemaker and a cohort with loop recorder was identified. Outcome was the cumulative incidence of AF within the first 2 years from 3-months after device implantation. Results: At the end of first 3-months after device implantation, 16,383 patients were free of AF and were included in the current study. In comparison to controls (n = 86,167), patients with PM had higher cumulative incidence of AF (5.2% vs 2.7%, P < 0.001)). Due to interaction with age, patients were divided into three age-groups) and the relative risk for the diagnosis of AF were: < 70 years (HR 4.46, 95% CI 3.65–5.44); 70–79 years (HR 2.60, 95% CI 2.27–2.98); and ≥ 80 years (HR 1.29, 95% CI 1.15–1.45). For comparison between PM and loop-recorder cohort (1:1 matching), 2202 patients were available in both groups. The incidence of AF within the first 2-years in the both groups was 7.9% vs. 8.4% (loop vs pacemaker). Conclusions: Patients with PM have an increased risk of being diagnosed with AF in comparison to general cohort likely due to continuous monitoring.