Abstract 13747: Investigation of the Probability of Spontaneous Conversion From Atrial Fibrillation to Sinus Rhythm Utilizing Continuous Rhythm Monitoring

Abstract

Introduction: Atrial fibrillation (AF) recurrence or spontaneous conversion to sinus rhythm (SR) are regarded as random events. Hypothesis: We hypothesized that the probability of spontaneous conversion to SR decreases as more time is spent in AF. We attempt to quantify this phenomenon and investigate factors that can affect this probability. Methods: Cardiac rhythm histories of 1195 patients (age 73.0 ± 10.1, follow-up: 349 ± 40 days; 14533 AF episodes) with implantable devices were reconstructed and analyzed. No patients received cardioversion, AF ablation, or any obvious AF therapies during follow-up. Patients with no AF recurrence or continuous AF during follow up were excluded. Hierarchical regression methods were employed to investigate the time course of the probability of rhythm change and factors that influence it. Results: Probabilities of spontaneous conversion from AF to SR (solid blue line) and recurrence of AF in patients with SR (solid red line) are shown in the Figure. For patients in AF , spontaneous conversion probability significantly decreases with time spent in AF and plateaus after ~7 days (dotted blue line). Similarly for patients in SR, increasing time in SR reduces the probability of developing AF (solid red line) and plateaus after ~7 days (dotted red line). Patient age (p<0.001), LVEF (p<0.05) and presence of coronary artery disease (p<0.01) significantly influence the spontaneous conversion probabilities independent from AF burden. Conclusions: Spontaneous SR conversion or AF recurrence diminishes with increasing time spent in AF or SR, respectively, and are influenced by several patient-related factors. These findings suggest that patients should be closely monitored after AF recurrence or SR conversion.