['The purpose of this study was to identify the relationship of preoperative and postoperative left atrial volume indices and dimensions with successful restoration of sinus rhythm after the maze operation.', 'Forty-three patients who underwent the Cox-maze III procedure for permanent atrial fibrillation in conjunction with surgical intervention for various heart diseases were evaluated. Echocardiographic studies were performed preoperatively and 3 months postoperatively. Volumes and dimensions were corrected for body surface area and analyzed.', 'Sinus rhythm was restored and maintained in 36 (83.7%) of the 43 patients. The preoperative left atrial volume index of the group with successful restoration of sinus rhythm (group A) was significantly smaller than that of the group with unsuccessful restoration (group B: 76.7 +/- 16.4 vs 108.9 +/- 43.9 mL/m2, P = .047). In group A the volume index (76.7 +/- 16.4 vs 52.3 +/- 15.0 mL/m2, P < .001) and dimension index (35.8 +/- 6.2 vs 30.8 +/- 4.7 mL/m2, P < .001) decreased significantly 3 months after the operation. No such significant changes were found in group B. The duration of arrhythmia for group A was significantly shorter than that for group B (3.4 +/- 2.8 vs 13.7 +/- 8 years, P = .001).'] Is preoperative left atrial volume index a predictor of successful sinus rhythm restoration and maintenance after the maze operation?