Frequency, cause and effect on operative outcome of depressed left ventricular ejection fraction in mitral stenosis.

To assess the incidence, pathophysiology and influence on operative outcome of a depressed left ventricular (LV) ejection fraction (EF) in patients with mitral stenosis (MS), demographic, hemodynamic and cineangiographic data on 72 patients (16 men, 56 women, aged 19 to 75 years) with isolated MS were reviewed. Of the 45 who had mitral commissurotomy or replacement, operative course and functional class before and after surgery were assessed. Of the 72 patients, 21 (29%) had an LVEF < or = 0.50. These 21 were similar to the 51 with an LVEF > 0.50 in age, gender, heart rate, intracardiac pressures, transvalvular gradient and valve area, but they had larger LV end-diastolic (79 +/- 19 [mean +/- SD] vs 59 +/- 15 ml/m2, p < 0.001) and end-systolic volumes (46 +/- 13 vs 23 +/- 8 ml/m2, p < 0.0001). Of the 45 subjects undergoing surgery, operative outcome was similar in the 14 with a depressed and the 31 with a normal LVEF. Thus, about 1/3 of patients with isolated MS have a depressed LVEF. Compared with those with MS and a normal LVEF, these subjects have hemodynamic derangements of similar severity, but they have larger LV end-diastolic and end-systolic volumes, suggesting that impaired LV contractile function or excessive afterload (rather than diastolic underfilling), or both, is the cause of a low LVEF. Those with an LVEF < or = 0.50 who undergo valve surgery have a similar operative outcome as those with an LVEF > 0.50.