OUTCOME OF MITRAL-VALVE REPAIR IN PATIENTS WITH PREOPERATIVE ATRIAL-FIBRILLATION - SHOULD THE MAZE PROCEDURE BE COMBINED WITH MITRAL VALVULOPLASTY

To examine late outcome of mitral valve repair in patients with preope rative atrial fibrillation, we reviewed the cases of 323 consecutive p atients who underwent mitral valvuloplasty for mitral regurgitation fr om 1980 to 1991; average age of 215 men and 108 women was 64 years (ra nge 14 to 88 years), and 224 patients (70%) were in New York Heart Ass ociation class III or IV before operation. The main indications for op eration were severe mitral regurgitation (76%), coronary artery diseas e with associated mitral regurgitation (15%), and aortic valve disease (6%). At the time of mitral valve repair, coronary artery bypass graf ting was done in 35% of patients, aortic valve replacement was done in 7%, and multiple other procedures were done in 10%. For all patients, the 30-day mortality rate was 2.5% (70% confidence limits 1.6%, to 3. 4%) and survivorships at 3 and 5 years were 81% and 76%, respectively. Before operation, 216 patients were in sinus rhythm and 97 patients h ad atrial fibrillation; in the latter group, 11 had recent onset of at rial fibrillation within 3 months preceding mitral valve repair. Compa ring patients with preoperative atrial fibrillation to those with sinu s rhythm, we found no significant difference in operative mortality (3 % versus 1.9%) or 5-year survivorship (74.3% +/- 6.3% versus 76.9% +/- 4.0%). A late follow-up, atrial fibrillation was present in 5% of pat ients with preoperative sinus rhythm, 80% of patients with preoperativ e chronic atrial fibrillation, and 0% of patients with preoperative re cent onset atrial fibrillation (p < 0.01). The left atrial size by ech ocardiography was larger in patients with preoperative atrial fibrilla tion compared with that in those with sinus rhythm (59 +/- 1.4 mm vers us 50.9 +/- 0.7 mm; p < 0.05). There was, however, only a weak correla tion between preoperative left atrial size and late atrial fibrillatio n. Further, age, gender, and associated coronary artery disease did no t correlate with presence of atrial fibrillation at late follow-up. Pr evalence of late thromboembolic events was similar in patients with pr eoperative sinus rhythm compared with that in those with atrial fibril lation. These data suggest that mitral valve repair should be done bef ore or soon after the onset of atrial fibrillation to maximize the cha nce of postoperative sinus rhythm and avoid long-term anticoagulation with warfarin. However, the early and late results of mitral valve rep air in patients with chronic atrial fibrillation are good, and concomi tant operation for supraventricular arrhythmia must have negligible mo rbidity and no adverse effect on operative mortality.