Abstract 16640: Impact of Early Valve Repair for Patients With Asymptomatic Mitral Regurgitation and Normal Left Ventricular Function on Exercise Capacity
Background: Although ACC/AHA guidelines recommend mitral valve repair (MVP) for asymptomatic patients with mitral regurgitation (MR) and normal left ventricular (LV) function (class IIa), there have been little evidences investigating the role of early surgical intervention. The aim of this study is to examine the impacts of early MVP by assessing the change of functional capacity and LV function.
Methods: Twenty-two patients with MR were prospectively enrolled in this study. All patients underwent successful MVP. There were 18 men and 4 women with a mean age of 58+/−12 years. Cardiopulmonary exercise testing (CPX) was performed to measure anaerobic threshold (AT), ΔVO2/ΔW, and ΔVE/ΔVCO2 slope before, early and late after MVP. Simultaneous echocardiography was performed to assess LV function. We compare the results between patients with preoperative NYHA class I and LV ejection fraction (EF)>60% (Group A, n=7) and those with more than NYHA class II symptom and/or reduced LV function (Group B, n=15). As a control group, CPX was performed in normal population (n=7).
Result: Preoperative LV dimension, EF, and degree of MR were similar between groups. However E/e′ (A : 10±3.1 vs B : 23±4.2 ; p=0.05) and mean degree of tricuspid valve regurgitation (A : 0.6±0.8 vs B : 1.7±0.9 ; p=0.01) were significantly higher in the Group B. Degree of MR decreased less than grade 1 in all patients after MVP. In the Group B, NYHA class improved from 2.4±0.6 to 1.3±0.45 (p<0.001). E/e′ remained significantly higher in the Group B at late period (A: 17±4.7 vs B : 26±9.8 ; p=0.04). The AT, ΔVO2/ΔW, and ΔVE/ΔVCO2 values declined immediately after the operation and were restored to baseline level at the late period in both groups. Compared with control, functional capacity remained significantly low even after MVP in Group B patients (Fig).
Conclusion: Our study demonstrated that early MVP was feasible in asymptomatic MR with normal LV function in terms of preserved exercise capacity and LV diastolic function.
- © 2010 by American Heart Association, Inc.