Study of the Value of Corrected Ejection Fraction in the Evaluation of Left Ventricular Function in Patients with Mitral or Aortic Regurgitation

Abstract

Evaluation of left ventricular function in the presence of valvular regurgitation is still a clinical problem because ejection phase indices including ejection fraction are heavily dependent on preload and afterload and cannot be regarded as reliable indices of contractility in diseases associated with altered loading conditions. The authors attempted to evaluate the usefulness of the new index-corrected ejection fraction in the evaluation of left ventricular (LV) function in patients with chronic mitral (MR) or aortic regurgitation (AR). The study included 21 patients with chronic severe MR (11 patients) and AR (10 patients) with a mean age of 18 years. All patients underwent valve replacement or repair. Echo Doppler study was performed preoperatively and postoperatively and included measurement of the following LV parameters: end-diastolic dimension (EDD), end-diastolic volume (EDV), end-systolic dimension (ESD), end-systolic volume (ESV), ejection fraction (EF), systolic blood pressure/end-systolic dimension (SBP/ESD); also mitral and aortic stroke volume were calculated cross-sectional area (CSA) x time velocity integral TVI. Corrected ejection fraction (EFc) was derived from the following equation: EFc = [EF + square root of (ASV x MSV) / EDV] / 2. The mean preoperative EFc did not change significantly after surgical correction of mitral or aortic regurgitation. Preoperative EFc did not show significant difference compared with postoperative EF in the two groups. Preoperative EFc correlated significantly with other preoperative and postoperative indices of LV function. Postoperative EFc showed very close correlation with other postoperative parameters. Thus, using the new index-corrected ejection fraction in the assessment of LV function in patients with mitral or aortic regurgitation has several advantages: Noninvasive, independent of loading changes, helpful in predicting the immediate postoperative clinical course, and a reliable index for evaluation of LV systolic function preoperatively and postoperatively.