LEFT-VENTRICULAR FUNCTION FOLLOWING CONVENTIONAL MITRAL-VALVE REPLACEMENT IN PATIENTS WITH CHRONIC MITRAL REGURGITATION

Conventional mitral valve replacement (MVR) for patients with chronic mitral regurgitation (MR) is usually associated with decrease in left ventricular (LV) ejection fraction (EF). This study investigated the e ffect of preoperative LV size on LV performance and examined loading c onditions before and after conventional MVR. Echocardiographic study m as performed on 13 and 9 patients with LV end-systolic dimension of le ss than 26 mm/m(2) (group A) or greater than 26 mm/m(2) (group B), res pectively. Postoperatively, the LV end-diastolic dimension and EF decr eased significantly in both groups. There was a decrease in end-systol ic wall stress after MVR. Preoperative LV forward flow estimated by th e normalized aortic peak velocity increased significantly in both grou ps after surgery. The decrease in EF after MVR is not the result of in creased systolic loading, and LV performance may not decrease after co nventional MVR. Preoperative echocardiographic evaluation can provide important prognostic information in patients with MR undergoing MVR.