Rheumatic mitral valve disease may lead to atrial fibrillation due to anatomical and functional disorders of the left atrial myocardium. After mitral valve surgery some patients in atrial fibrillation recover sinus rhythm, but the majority of them remains fibrillated. This study was undertaken with the purpose of identify, in patients operated on for mitral valve disease with atrial fibrillation, those factors that could predict a return to sinus rhythm post-operatively. The following variables were retrospectively studied: age, gender, duration of the arrhythmia pre-operatively, left atrial diameter, ejection fraction, type of valve lesion, surgical technique for correction, and previous cardiac surgery. Data was obtained from the medical history, ECG, echocardiogram and surgical note. There was no statistical significant difference between patients that returned to sinus rhythm and those that remained in atrial fibrillation, regarding age, gender, arrhythmia duration, left atrial diameter, ejection fraction, kind of technique, and previous heart surgery. Mitral regurgitation associated to left atrial less than 52 mm diameter was predictive for return to sinus rhythm (OR = 1,945; p = 0,02).The prediction of persistent post-operative atrial fibrillation may lead to changing surgical stratergies in patients with mitral valve disease. In this small series of patients, the association of mitral regurgitation and left atrial size less than 52 mm was predictive of conversion to sinus rhythm after conventional post-operative therapy.
