Atrial fibrillation recurrence and spontaneous conversion to sinus rhythm after cardiac surgery: Insights from 426 patients with continuous rhythm monitoring.

Abstract

Cardiac surgery may influence occurrence and persistence of atrial fibrillation (AF). In patients with a history of cardiac surgery and postoperative pacemaker or implantable cardioverter defibrillator implantation we attempted to quantify AF characteristics and investigate factors that influence AF recurrence. In 426 patients (319 male; age: 73 SD: 9 years) with a history of cardiac surgery (364 CABG; 69 mitral valve; 57 aortic valve and 59 combination procedures) the heart rhythm history (mean: 351 days SD: 54 days) was reconstructed and investigated for AF recurrence patterns. AF developed and subsequently recurred in 75% of patients (n = 320). The mean AF burden in these patients was 0.21 (21% of the total observed time spent in AF) and 4085 episodes of AF were observed and analyzed. AF episodes spontaneously terminated within 24 h (n = 2509), 48 h (n = 700), 72 h (n = 279), and 1 week (n = 31). The probability of spontaneous conversion to sinus rhythm (SR) decreased with time spent in AF and plateaued after approximately 7 days. Patient age, LVEF and presence of coronary artery disease significantly influenced the probability of spontaneous conversion to SR. Type of cardiac surgery also significantly influenced AF episode characteristics. AF episodes are common in patients with a history of cardiac surgery. Spontaneous conversion to SR diminishes with increasing time spent in AF and is influenced by AF characteristics and several patient-related factors. Continuous monitoring can provide detailed information about AF recurrence that may immensely improve our understanding and influence the clinical management of AF.