[Clinical outcome and factors affecting surgical decision for repair versus replacement in patients with mitral regurgitation]

Abstract

Objective: We aimed to identify characteristics differentiating patients undergoing mitral valve replacement versus valve repair for mitral regurgitation (MR) and to investigate retrospectively mid-term clinical and functional outcomes.

Methods: From January, 2004 to January, 2009 146 patients underwent mitral valve surgery (62 male / 84 female; age: 55.9+/-13.6 [18-80] years) by one surgical team. Mitral valve replacement was performed in 101 patients (69.2 %) and valve repair was performed in 45 patients (30.8%). Mean follow-up time was 586+/-413 days. Life tables were constructed for the analysis of 5-year complication free survival and comparisons were performed between the groups using Log-rank test within 95%CI.

Results: The choice of surgical technique depended on the etiology of MR. Degenerative (p=0.001) and ischemic (p=0.014) MR were more common in patients undergoing repair whereas patients with complex rheumatic mitral valve disease (p=0.001) with subvalvular involvement commonly underwent replacement. Overall 30-day mortality was 3.2% (replacement, 3.96%vs repair, 2.22%, p=0.59). Although there was no significant difference between the groups regarding baseline left ventricular ejection fraction (EF) (ischemic p=0.61; non-ischemic p=0.34), improvement was more pronounced in the repair group for both etiologies (ischemic MR, p=0.001; non- ischemic MR p=0.002). Survival at 5-years was 91.7+/-4.7% after repair and 83.5+/-9.2% after replacement, respectively (p=0.83). Freedom from grade 2 or more mitral regurgitation, reoperation, endocarditis, and thromboembolism were 95+/-5% vs 97+/-3% (p=0.71); 95+/-4% vs 98+/-2% (p=0.98); 94+/-4% vs 100% (p=0.16); and 85+/-8% vs 100% (p=0.095) in replacement and repair groups, respectively.

Conclusion: This study demonstrates that mitral valve repair is associated with an acceptable operative mortality, satisfactory mid-term survival and better preservation of left ventricular function. Significant differences in favor of repair are expected in long-term follow-up particularly regarding freedom from thromboembolism and endocarditis.