Atrial Function as an Independent Predictor of Postoperative Atrial Fibrillation in Patients Undergoing Aortic Valve Surgery for Severe Aortic Stenosis

Background: Postoperative atrial fibrillation (POAF) is a common, clinically relevant, but hardly predictable complication after surgical aortic valve replacement. The aim of this study was to test the role of preoperative left atrial longitudinal strain as a predictor of POAF in clinical practice.Methods: Sixty patients scheduled for aortic valve replacement for severe isolated aortic stenosis, in stable sinus rhythm, were prospectively enrolled and underwent full clinical, biochemical, and transthoracic echocar-diographic assessment on the day before surgery. Left atrial strain-derived peak atrial longitudinal strain (PALS) and peak atrial contraction strain (PACS) were obtained. The occurrence of POAF was evaluated during the hospital stay after the intervention.Results: POAF was present in 26 of 60 patients (43.3%). Among all clinical variables examined, age showed a significant correlation with POAF (P = .04), while no significant differences were noted regarding preoperative symptoms, cardiovascular risk factors, medications, and biochemical data. As for the echocardiographic parameters, only PALS and PACS showed strong, significant correlations with the occurrence of arrhythmia (P < .0001 on univariate analysis), with areas under the curve of 0.87 +/- 0.04 (95% CI, 0.76-0.94) for PALS and 0.85 +/- 0.05 (95% CI, 0.73-0.93) for PACS. In two comprehensive multivariate models, PALS and PACS remained significant predictors of POAF (odds ratio, 0.73 [95% CI, 0.61-0.88; P = .0008] and 0.72 [ 95% CI, 0.59-0.87; P = .0007]). No significant interaction was detected between PALS or PACS and other clinical and echocardiographic variables, including age, E/E' ratio, and left atrial enlargement.Conclusions: PALS and PACS indexes are routinely feasible and useful to predict POAF in patients with severe isolated aortic stenosis undergoing surgical aortic valve replacement.