Mitral valve reconstruction and replacement for ischemic mitral insufficiency: seven years' follow up.

BACKGROUND AND AIMS OF THE STUDY

Patients with ischemic mitral incompetence have a high operative risk whether the valve is repaired or replaced. The advantage of repair over replacement is unclear in this subgroup of patients.

METHODS

Between April 1986 and December 1998, 337 patients underwent surgery for ischemic mitral valve insufficiency. Coronary artery bypass grafting (CABG) was carried out concomitantly in 314 cases (93.2%). Valve repair was performed in 140 patients (operative mortality rate 12.1%). The surgical risk in patients with a left ventricular ejection fraction (LVEF) of 10-30% was higher (operative mortality rate 33.3%) than in those with LVEF >30% (operative mortality rate 8.4%). Actuarial survival rates were 75.4%, 66.8% and 61.7% after 2, 5 and 7 years, respectively. Mitral valve replacement was performed in 197 patients (operative mortality rate 14.2%). The surgical risk in patients with a LVEF of 10-30% (operative mortality rate 30.3%) was greater than in those with a LVEF of >30% (operative mortality rate 11.0%).Actuarial survival rates after replacement were 78.6%, 73.4% 67.2% after 2, 5 and 7 years, respectively.

RESULTS

Our initial analysis showed that, after mitral valve repair, mortality during follow up was greater in patients with residual mitral valve insufficiency of more than grade I. Subsequent outcome was superior when repair was evaluated perioperatively with transesophageal echocardiography. When mitral insufficiency was persistently more than grade I after repair, mitral replacement was performed. A total of 105 patients was analyzed with no or maximum grade I mitral insufficiency following valve repair; actuarial survival rates were 81%, 78.4% and 77.2% after 2, 5 and 7 years' follow up.

CONCLUSIONS

Patients with highly impaired LV function and ischemic mitral insufficiency are at high risk during valve repair or replacement, and cardiac transplantation should be considered for this group. However, patients with ischemic mitral insufficiency and moderately impaired LV function can undergo valve repair or replacement with an acceptable prognosis. The goal of mitral valve repair should be to reduce valvular insufficiency to at least grade I. If this is not the case, then the prognosis of repair is worse than after valve replacement. Thus, the surgeon should replace the valve during the same operation.