Identifying patients with degenerative mitral regurgitation for mitral valve repair and replacement: a transesophageal echocardiographic study.

OBJECTIVE

We sought to preoperatively identify the suitability of patients with degenerative mitral valve (MV) regurgitation for MV repair (MVR) and MV replacement.

BACKGROUND

MVR is the preferred method of treatment over MV replacement, if surgically feasible. MVR preserves left ventricular function and decreases risk of hemolysis, thromboembolism, and-in the absence of anticoagulation-hemorrhage. However, the ability to identify patients suitable for MVR preoperatively is somewhat limited.

METHODS

In all, 76 patients underwent MV operation for severe symptomatic mitral regurgitation. The decision to operate was at the discretion of the referring physician in consultation with respective cardiothoracic surgeons at two separate, nonrelated institutions. All patients underwent preoperative and/or intraoperative transesophageal echocardiographic studies.

RESULTS

In all, 35 patients (46%) underwent MVR and 41 (54%) underwent MV replacement. There was no difference in the percentage of MVRs between the two institutions: 17 cases (41%) at Hahnemann University Hospital, Philadelphia, Pa, versus 18 cases (53%) at Northwestern University Memorial Hospital, Chicago, Ill (P = not significant). Age was found to be a significant univariate predictor with older age favoring MV replacement. On average, patients who underwent MVR were 11 years younger then those who underwent MV replacement. Heart failure was also found to be a significant univariate predictor: as New York Heart Association functional class worsened, MV replacement was more likely. Echocardiographic variables favoring MVR included chordal length (>29 mm, P <.001), length of posterior mitral leaflet (>17 mm, P <.008), and length of anterior leaflet (>25 mm, P <.01). The only echocardiographic parameter favoring replacement was the presence of anterior mitral annular calcification. Using multivariate analysis, older age (>63 years) was again a significant predictor favoring MV replacement (P <.002; odds ratio [OR] 20). Longer chordal length (>29 mm) was the strongest predictor favoring MVR (P <.001; OR 11.2). Longer length of the posterior leaflet (>17 mm; OR 5.07) and mitral annulus size > 35 mm (OR 7.75) were also significant multivariate predictors favoring MVR. The presence of anterior mitral annular calcification favored MV replacement using multivariate analysis (OR 25).

CONCLUSIONS

Patients suitable for MVR can be identified preoperatively using a combination of clinical and echocardiographic parameters.