Atrial fibrillation after isolated coronary surgery. Incidence, long term effects and relation with operative technique

INTRODUCTION: Postoperative atrial fibrillation after isolated coronary revascularization has been associated with increased morbidity and mortality. Aim of present investigation was to evaluate incidence of postoperative atrial fibrillation and its prognostic role in patients undergoing isolated coronary artery by-pass and disclose possible differences between off-pump and cardiopulmonary assisted revascularization. METHODS: Prospective cohort study of 229 patients undergoing isolated coronary artery by-pass at a tertiary heart surgery Centre. Off-pump treated patients were significantly older (70.5 vs 64.9 years, p<0.001). No other baseline differences were found. Patients who developed postoperative atrial fibrillation were followed up for an average period of 2 years. RESULTS: Post-operative occurred in 56/229 (24.1% after cardiopulmonary and 24.6% after off-pump coronary artery by-pass). Left atrium diameter was the only independent predictive factor (odds ratio =1.15, 95% confidence interval 1.02-1.30, p<0.001). All patients with postoperative atrial fibrillation were treated and discharged in sinus rhythm, in 6/56 recurred, only in one persisted. One patient died during follow up. No stroke was recorded. CONCLUSIONS: After isolated surgical revascularization, atrial fibrillation occurred in 24% without differences related to operative technique. Recurrence of atrial fibrillation occurred in 6/56 patients (10.7%) however only in 1 persisted. Early and late mortality did not show relation with post-operative atrial fibrillation probably due to immediate treatment with recovery of sinus rhythm before discharge.