Mechanism of recurrent ischemic mitral regurgitation after annuloplasty: continued LV remodeling as a moving target.

BACKGROUND

Patients who undergo ring annuloplasty for ischemic mitral regurgitation (MR) often have persistent or recurrent MR. This may relate to persistent leaflet tethering from left ventricle (LV) dilatation that is not relieved by ring annuloplasty. Therefore, the purpose of this study was to test the hypothesis that recurrent MR in patients after ring annuloplasty relates to continued LV remodeling.

METHODS AND RESULTS

Serial echoes were reviewed in 30 patients (aged 72+/-11 years) who showed recurrent MR late (47+/-27 months) versus early (3.8+/-5.8 months) after ring annuloplasty for ischemic MR during coronary artery bypass grafting without interval infarction. Patients with intrinsic mitral valve disease were excluded. Echocardiographic measures of MR (vena contracta and jet area/left atrial area) and LV remodeling (LV dimensions, volumes, and sphericity) were assessed at each stage. The degree of MR increased from mild to moderate, on average, from early to late postoperative stages, without significant change in LV ejection fraction. Changes in MR paralleled increases in LV volumes and sphericity index at end-systole and end-diastole. The only independent predictor of late postoperative MR was LV sphericity index at end-systole.

CONCLUSIONS

Recurrent MR late after ring annuloplasty is associated with continued LV remodeling, emphasizing its dynamic relation to the LV.