The Cox-Maze Procedure for Atrial Fibrillation Concomitant with Mitral Valve Disease

Kim, Ki Bong; Jo, Kwang Ree; An, Hyuk

Abstract

BACKGROUND: The sugical results of the Cox-Maze procedure (CMP) for lone atrial fibrillation (AF) have proven to be exellent. However, those for AF associated with mitral valve (MV) disease have been reported to be a little inferior. MATERIALS AND METHODS: To assess the efficacy and safety of the CMP as a combined procedure with MV operation, we studied retrospectively our experiences. Between April 1994 and October 1997, we experienced 70 (23 males, 47 females) cases of CMP concomitantly with MV operation. RESULTS: The etiologies of MV disease were rheumatic in 67 and degenerative in 3 cases. The mean duration of AF before sugery was 66+/-70 months. Fifteen patients had the past medical history of thromboembolic complications, and left atrial thrombi were identified at operation in 24 patients. Twelve cases were reoperations. Aortic cross clamp (ACC) time was mean 151+/-44 minutes, and cardiopulmonary bypass (CPB) time was mean 246+/-65 minutes. Concomitant procedures were mitral valve replacement (MVR) in 19, MVR and aortic valve replacement (AVR) in 14, MVR and tricupid annuloplasty (TAP) in 8, MVR with AV repair in 3, MV repair in 11, MVR and coronary artery bypass grafting (CABG) in 2, MVR and AVR and CABG in 1, redo-MVR in 10, redo-MVR and redo-AVR in 2 patients. The rate of hospital mortality was 1.4% (1/70). Perioperative recurrence of AF was seen in 44 (62.9%), and atrial tachyarrhythmias in 10 (14.3%), low cardiac output syndrome in 4 (5.7%), postoperative bleeding that required mediastinal exploration in 4 (5.7%) patients. Other complications were acute renal failure in 2, aggravation of preoperative hemiplegia in 1, and transient delirium in 1 patient. We followed up all the survivors for 16.4 months (3-44months) on an average. Sinus rhythm has been restored in 65 (94.2%) patients. AF has been controlled by operation alone in 73.9% and operation plus medication in 20.3%. Two patients needed permanent pacemaker implantation; one with sick sinus syndrome, and the other with tachycardia-bradycardia syndrome. Only two patients remained in AF. We followed up our patients with transthoracic echocardiography to assess the atrial contractilities and other cardiac functions. Right atrial contractility could be demonstrated in 92% and left atrial contractility in 53%.We compared our non-redo cases with redo cases. Although the duration of AF was significantly longer in redo cases, there was no differences in ACC time, CPB time, postoperative bleeding amount and sinus conversion rate.
CONCLUSIONS
In conclusion, the CMP concomitant with MV operation demonstrated a high sinus conversion rate under the acceptable operative risk even in case of reoperation.