Abstract 2648: Transient Atrial Fibrillation Within the First Month After Dual Chamber Pacemaker Implantation
Background: Following pacemaker (PPM) implant, atrial fibrillation (AF) is often diagnosed for the first time based on detection of stored atrial high rate episodes (AHRE). However, there are no prospective data regarding the time course of developing AF following dual chamber PPM implantation.
Methods: We evaluated data from the Silent Atrial Fibrillation Detection with Stored EGMs (SAFE) registry, which was a multi-center, prospective registry of patients undergoing dual chamber PPM implant. No patient had prior history of AF. Device interrogations were performed at 2-week, 3-, 6-, and 12-months post-implantation. An AHRE was defined as an atrial rate ≥ 180 bpm lasting ≥ 5 minutes.
Results: 1488 patients (55% male, 74 ± 12 years) underwent PPM implantation. During the first month, 47 (3.7%) patients were diagnosed with AF for the first time. In 33 (70%) of these 47 patients, AF lasted between 5 and 60 minutes. Overall, the mean duration of AF was 133 ± 276 minutes (range: 5.4 minutes – 22.9 hours). A majority (81%) of these early episodes occurred within the first 15 days of implant. Twenty-four (51%) of these 47 patients did not have AF beyond this first month. Patients who did and did not have AF beyond the first month were similar with respect to baseline demographics, the use of active versus passive atrial leads, duration of first AF event, and time to first AF episode (Table⇓).
Conclusions: In the SAFE registry, nearly 4% of patients with no history of AF exhibited AF in the first 30 days after PPM implant, with a majority occurring within the first 15 days post-implant. However, half of these patients failed to have another AHRE after the first month. These ``transient” episodes of AF may represent proarrhythmia from atrial lead insertion, de novo AF, or simply first-detection AF that was previously silent. Long-term follow-up studies are needed to determine the clinical significance of these transient episodes.