Abstract 3061: Optimal Left Atrial Volume Reduction Surgery (LA-VR) with the Cox-Maze Procedure (MAZE) for Better Postoperative LA Global Function
Background: LA-VR with MAZE has been reported to facilitate sinus rhythm recovery even in patients with refractory atrial fibrillation (AF) with LA enlargement; however, optimal extent of LA volume reduction for better postoperative LA global function has not been elucidated.
Methods: LA-VR with MAZE in association with mitral valve surgery were performed in 51 AF patients with LA enlargement (diameter ≥60 mm). Postoperative maximum LA volume (maxV), LA booster pump function (BPF, %), reservoir function (RF, %), and conduit function (CF, %) were calculated from the LA volume-cardiac cycle curves obtained from MRI. The correlation between maxV and each LA function was assessed with regression analyses 1 year after the operation.
Results: Defibrillation rate was 86% 1 month postop. and 88% 1 year postop. By the LA-VR, LA volume was drastically reduced from 354 ± 89 to 147 ± 42 mL (preop. and 1 month postop., p<0.0001), and further reduced (116 ± 35 mL, p<0.05) during the follow-up (=reverse remodeling).
Conclusions: More volume-reduced LA recovered better LA contraction and compliance accompanying with LA reverse remodeling; however, over-reduced LA aggravated LA compliance. Extent of reduction did not influence CF so much. Appropriate LA-VR may be essential for better LA global function.