Assessment of preoperative left ventricular function in patients with mitral regurgitation: value of the end-systolic wall stress-end-systolic volume ratio.

Abstract

Twenty-one patients with symptomatic, chronic, severe mitral regurgitation (MR) but without other valvular heart disease or coronary disease were evaluated to determine which hemodynamic and angiographic factors might be prognostic of surgical outcome. Sixteen patients were in New York Heart Association functional classes I or II postoperatively and formed group A. One patient remained in class III postoperatively and four patients died perioperatively; they constitute group B. End-diastolic volume index (EDVI) was less for group A than for group B, 119 +/- 25 ml/m2 vs 170 +/- 28 ml/m2 (p less than 0.001). End-systolic volume index (ESVI) was also lower in group A, 39 +/- 19 ml/m2 vs 72 +/- 32 ml/m2 for group B (p less than 0.01). The ratio of end-systolic wall stress to end-systolic volume index (ESWS/ESVI) was examined in normal persons and in groups A and B. This ratio was significantly lower in both groups than in normal persons, indicating relatively greater end-systolic volume at a given wall stress, suggesting left ventricular dysfunction. The ESWS/ESVI ratio in group B, 2.2 +/- 0.2, was significantly less than in group A, 3.3 +/- 0.4 (p less than 0.001). The variables of age, pulmonary capillary wedge pressure, EDVI, ESVI, ejection fraction and the ESWS/ESVI ratio were subjected to stepwise discriminant multivariate analysis to determine if any were independent predictors of outcome. The only independent predictor determined by this method was the ESWS/ESVI ratio (p less than 0.001). We conclude that the ESWS/ESVI ratio may be helpful in evaluating left ventricular function and operative risk in patients with chronic, symptomatic MR.