Long-term outcome after mitral valve repair

BACKGROUND: Several studies reported excellent long-term results after mitral valve repair for regurgitation, however a number of patients still experience recurrent mitral valve regurgitation which requires reoperation. We have evaluated the long-term outcome of a consecutive series of patients who underwent mitral valve repair for regurgitation in an attempt to identify the risk factors associated with late failures. PATIENTS AND METHODS: One-hundred and sixty-four patients underwent mitral valve repair for ischemic and degenerative mitral valve regurgitation. Seventy-two patients underwent echocardiographic evaluation a median of 5.6 years after surgery. RESULTS: Ten-year survival freedom from any fatal cardiac event was 75.9% and survival freedom from redo mitral valve surgery was 93.8%. Multivariable analysis showed that residual mitral valve regurgitation grade>1 as assessed during the immediate postoperative period (at 10-year, 60.6% vs. 95.7%, p=0.001, RR 20.7, 95%C.I. 3.4-125.3) and chronic obstructive pulmonary disease/asthma (at 10-year 66.8% vs. 95.2%, p=0.013, RR 12.0, 95%C.I. 1.7-85.2) were predictors of redo mitral valve surgery. The same findings were observed also among patients with myxomatous degenerative disease. At echocardiographic follow-up, no significant improvement was detected in terms of left ventricular ejection fraction, whilst mitral valve regurgitation grade (median, 3 to 1), New York Heart Association class (median, 2 to 1) and left atrium diameter (median, 50 to 44 mm) decreased significantly. CONCLUSIONS: This study confirms the excellent clinical long-term results after mitral valve repair. An adequate repair technique is advocated in order to decrease the immediate postoperative rate of residual regurgitation>1 as this is a main determinant of late failures requiring redo mitral valve surgery. Further studies are required to better define the possible causative role of chronic obstructive pulmonary disease and any underlying connective tissue metabolic disorder in late failures after mitral valve repair.