Adverse remodeling in atrial fibrillation following isolated aortic valve replacement surgery

Background: Atrial fibrillation (AF) is the most common arrhythmia with adverse clinical outcomes. Aortic valve replacement (AVR) is one of the most frequently performed cardiac surgeries, although there is scarce evidence on arrhythmic outcomes. We aimed to evaluate AF during the first year post- isolated aortic valve replacement surgery and its clinical, analytical, and echocardiographic predictors. Methods: Severe aortic stenosis patients with no prior atrial fibrillation submitted to isolated aortic valve replacement surgery were included in our study, of which 316 remained in sinus rhythm and 24 developed AF. We performed logistic regression searching for AF predictors and a longitudinal comparison between pre and post-operative echocardiographic data. Results: Postoperative AF (POAF), diabetes, and follow-up indexed Left Atrium Diameter (iLAD) were significantly higher in the group of patients developing AF. POAF and iLAD were independent AF predictors at follow-up. No differences between groups were found regarding baseline and follow-up echocardiographic data except for indexed Left Ventricle End-diastolic Diameter (LVED), which failed to decrease after surgery in the AF group. Conclusions: POAF and iLAD independently predicted AF at 1 year following isolated AVR surgery in aortic stenosis patients with no AF history. iLVED did not decrease significantly at follow-up in AF patients, possibly reflecting adverse ventricular remodeling.