RESUMO
BACKGROUND AND OBJECTIVES: The maze procedure is effective in restoring sinus rhythm (SR) in patients with atrial fibrillation (AF). We compared the left atrial mechanical function (LAMF) of patients whose rhythm was converted to SR after maze procedure with that of patients whose rhythm was not converted to SR and determined if preoperative left atrial volume index (LAVI) and immediate postoperative LAMF could predict conversion of AF to SR. SUBJECTS AND METHODS: We prospectively evaluated 80 patients with AF treated with the maze procedure between March 2005 and February 2007. LAMF was assessed by looking at left atrial ejection volume (LAEV) and ejection fraction (LAEF) during echocardiography before, 2 weeks after, and 6 months after the procedure. RESULTS: Of the 80 enrolled patients, 71 were converted to SR after the maze procedure (SR group), and 9 were not converted to SR (AF group). There were no significant differences in age, sex, hypertension, diabetes mellitus, renal failure, stroke, thyroid dysfunction, or smoking history between the groups. Pre-operative LAVI (p=0.010) was a predictor of conversion of AF to SR. LAEF gradually increased in the SR group during follow-up, but not in the AF group. CONCLUSION: LAMF recovered in the SR group after the maze procedure, irrespective of clinical presentation and initial LAMF. Preoperative LAVI predicted SR conversion.