Bigeminal potentials in the pulmonary vein indicate arrhythmogenic trigger of atrial fibrillation

Abstract

Background: The pulmonary veins (PVs) have unique electrophysiological properties triggering and maintaining atrial fibrillation (AF). Bigeminal PV electrical activity (PV bigeminy) during sinus rhythm has been reported; however, its mechanisms and clinical implication remain unclear. We hypothesized that PV bigeminy indicates arrhythmogenic activities and influences clinical outcome. Methods and Results: We retrospectively analyzed electrophysiological studies in 465 patients with AF who underwent first session PV isolation (PVI). PV bigeminy was observed in 30 PVs of 23 patients (4.9% of patients). PV bigeminy was observed in left inferior PV (LIPV) in 15 patients, which was the most prevalent, followed by left superior in seven and right superior in seven and right inferior in one. In response to atrial extra stimulus, the second PV potentials (PV2) showed decremental conduction properties, suggesting reentrant mechanisms involved (n = 5). Interestingly, AF was initiated from the 23 PVs with bigeminy in 21 patients (76.7% of 30 PVs with bigeminy), spontaneously or in response to drugs, which was significantly more prevalent from the AF initiation rate from each PV in the control 442 patients (182 firings in 1290 PVs, 14.1%, P