Atrial fibrillation (AF) is associated with considerable morbidity and increased resource utilization after coronary artery bypass graft surgery. In this study, we sought to determine whether patent foramen ovale (PFO) and atrial septal aneurysm are associated with an increased risk of postoperative AF in this patient population. We performed a database study on 1008 patients undergoing primary coronary artery bypass graft surgery. All patients were assessed for the development of postoperative AF from the day of surgery to hospital discharge. Atrial septal defects were identified during comprehensive intraoperative transesophageal echocardiographic examination. Postoperative AF was present in 124 (12.3%) patients. Patients with AF were significantly older and had a more frequent incidence of preoperative congestive heart failure, longer cross-clamp time, and prolonged hospital length of stay. PFO was present in 72 (7.1%) and atrial septal aneurysm in 23 (2.3%) patients. In these patients, postoperative AF was present in 14 (19.4%) patients with PFO and 8 (34.8%) patients with atrial septal aneurysm. Multivariate logistic regression analysis identified that PFO (odds ratio [OR], 1.95; 1.007-3.778; P = 0.047), age (OR, 1.03; 1.015-1.053; P = 0.0004), and history of congestive heart failure (OR, 2.55; 1.671-3.900; P < 0.0001) were predictive of postoperative AF.
Implications: The presence of patent foramen ovale is associated with new-onset postoperative atrial fibrillation after coronary artery bypass graft surgery. This finding requires further validation in future prospective trials.