Abstract 14196: Early Postoperative Atrial Fibrillation Combined With Preoperative Structural and Electrophysiological Parameters Are Good Predictors of Late Postoperative Atrial Fibrillation in Patients Undergoing Cardiac Surgery

Abstract

Introduction: Atrial fibrillation (AF) in the early postoperative phase (E-POAF) is likely caused by a combination of an arrhythmogenic substrate and surgery-induced stressors. Although E-POAF is regarded as a transient arrhythmia, recent findings suggest that patients with E-POAF also show late AF recurrences. The aim of this study is to determine the incidence of late postoperative AF (L-POAF) within 1 year of cardiac surgery and to identify its predictors. Hypothesis: The occurrence of L-POAF is associated with preexisting functional and structural atrial changes, and with occurrence of E-POAF. Methods: Ninety-two patients without history of AF undergoing first cardiac surgery were prospectively included. Intraoperatively, all patients received an implantable loop recorder (Reveal LINQ, Medtronic, USA) for continuous rhythm monitoring. Preoperative transthoracic echocardiograms (TTE), 12-lead electrocardiograms (ECG), blood samples, and clinical data were analyzed. Results: Eighty-five patients completed 1-year of follow-up. Incidence of L 5 -POAF (AF between 5-365 days after surgery) was 31.8%, whereas incidence of L 30 -POAF (AF between 30-365 days after surgery) was 15.3%. Independent predictors for L 5 -POAF were left atrial maximum volume indexed for body surface area (LAVi) and occurrence of E 5 -POAF (p=0.02, p<0.01, respectively). Independent predictors for L 30 -POAF were PR-interval and occurrence of E 30 -POAF (p=0.02, p=0.01, respectively). Predictive models for L-POAF based on TTE, biomarkers, and ECG showed moderate performance while addition of E-POAF strongly improved sensitivity and specificity (L 5 -POAF: 94.1% & 95.2%; L 30 -POAF: 83.3% & 91.0%, respectively) to predict L-POAF (see figure). Conclusion: Predictive models based on preoperative LAVi, increased PR-interval, and occurrence of E-POAF show excellent diagnostic accuracy for predicting occurrence of L-POAF.