Efficacy of Mitral Valve Surgery in Moderate Ischemic Mitral Regurgitation (MR)

Jung, Sung Ho; Choi, Jun Young; Lee, Jae Won

Abstract

BACKGROUND: Patients with mitral regurgitation (MR) in the setting of coronary artery disease have a dismal long-term prognosis whether treated medically or surgically. Moreover, the optimal management of moderate ischemic MR at the time of coronary artery bypass grafting (CABG) remains the subjects of controversy. Thus, the present retrospective study was undertaken to determine whether mitral valve surgery for moderate ischemic MR at the time of CABG would be preferable to CABG alone in terms of clinical outcome. MATERIALS AND METHOD: Between January 1997 and December 2003, 34 patients with moderate (Gr 3/4) ischemic MR underwent CABG alone (Group I, n=23) or CABG plus mitral valve surgery (Group II, n=11). Operative mortality, long-term survival and echocardiographic parameters were used to evaluate the efficacy of mitral valve surgery in patients with moderate ischemic MR. The mean follow-up durations of each group were 69.3+/-4.3 months and 53.1+/-4.9 months respectively. RESULT: There was no hospital mortality in both groups. There was one case of late mortality in Group I. The mean number of bypass graft was similar (3.8+/-1.2 vs 3.7+/-1.3 respectively). Cardiopulmonary bypass time was longer in group II (p=0.014). In group II, all of the patients received mitral annuloplasty using ring. On immediate postoperative echocardiogram, mitral regurgitation was reduced more in group II (p=0.002). Echocardiogram performed at last follow-up state showed no difference except the grade of MR between the two groups. Actuarial survival of both groups at 5 years was similar (95.5% vs 100%, p=0.48).
CONCLUSION
This study shows that in selected patients with moderate ischemic MR, CABG without mitral valve surgery might be sufficient. However, patients with low EF and NYHA functional class pre-operatively had tendency of significant residual MR, so mitral valve surgery should be necessary in these patients, and moreover, MR severity and left ventricle volume decreased more in mitral valve surgery group. Therefore, more large-scale studies are necessary to determine these effects on the ventricular function and long-term survival.