Update on mitral repair in dilated cardiomyopathy

Heart failure is one of the leading causes of hospitalization worldwide. Mitral regurgitation (MR) is a known complication of end-stage cardiomyopathy and is associated with a poor prognosis due to progressive mitral annular dilation. A vicious cycle of continuing volume overload, ventricular dilation, progression of annular dilation, increased LV wall tension, and worsening of MR and CHF occur. Commonly, these patients were managed medically with diuretics and afterload reduction, and frequently with mitral valve replacement, both of which have poor long term survival in patients with CHF and MR. Over a 10-year period we prospectively studied over 200 patients with cardiomyopathy and severe MR who underwent mitral valve repair utilizing an undersizing overcorrecting annuloplasty ring. The mortality was low with one intraoperative death and eight 30-day mortalities. There were 26 late deaths; 2 of these patients had progression of heart failure and underwent transplantation. The 1-, 2-, and 5-year actuarial survivals have been 82%, 71%, and 52%, respectively. The NYHA class has improved for all patients from a preoperative mean of 3.2 +/- 0.2 to 1.8 +/- 0.4 postoperatively. All patients demonstrated improvement in ejection fraction, cardiac output, and end diastolic volumes with a reduction in sphericity index and regurgitant volume at 2 years post operation. All of the observed changes contribute to reverse remodeling and restoration of the normal left ventricular geometry. Mitral valve repair is a safe and effective operative intervention that corrects MR and offers a new strategy for patients with MR and end-stage cardiomyopathy.