Surgical treatment of mitral regurgitation associated with enlarged left ventricle.

Background and aim of the study: Few long-term results exist of mitral valve replacement (MVR) in patients with chronic mitral regurgitation (MR) and severely enlarged left ventricle. Hence, the present study was conducted to provide additional data in this respect. Methods: Between April 1988 and September 2000,43 patients (28 males, 17 females; mean age 33.8 +/- 10.5 years; range: 13-58 years) with a left ventricular (LV) diastolic diameter (LVDD) >70 mm underwent MVR at Anzhen Hospital. MR was rheumatic in origin in 36 patients (80%) and congenital in nine (20%). Thirteen patients were in NYHA class II, and 32 in classes III -IV. The cardiothoracic ratio was 0.64 +/- 0.12 (range: 0.47-0.84). The ECG showed IV hypertrophy to be present in all patients. Echocardiography showed severe MR and IV hypertrophy in all patients: LVDD was 76.3 +/- 4.1 mm (range: 70.2-89.6 mm). MVR was performed under hypothermic cardiopulmonary bypass. Results: Two of 45 patients died perioperatively (mortality rate 4.4%). At two weeks after surgery, echocardiography showed a reduction in LVDD (from 76.3 +/- 6.5 to 65.0 +/- 5.2 mm) (p <0.01). Follow up was completed in 37 patients (82%). Mean follow up was 4.69 years (range: 1-12.33 years). Nine patients were in NYHA class 1, 21 in class II, and five in class III. Late mortality was 5%. LVDD was further decreased at late control from 76.3 +/- 6.5 to 60.0 +/- 6.1 mm (p <0.001). Conclusion: MVR is indicated in patients with mitral insufficiency and highly dilated ventricles. In addition, perioperative mortality was acceptable and late results satisfactory. Moreover, the intervention has the potential to reduce severe IV dilation, and in some cases to revert ventricular size to normal.