In congestive heart failure patients, a single measurement of left ventricular ejection fraction (LVEF) provides important prognostic information. The importance, if any, of improvement or worsening in serial LVEF has not been defined. The Department of Veterans Affairs Cooperative Vasodilator-Heart Failure Trials (V-HeFT) data base was analyzed to determine the prognostic importance of LVEF changes.
The data bases for V-HeFT I (n = 642) and V-HeFT II (n = 804) were analyzed. All patients had heart failure with documented exercise intolerance and abnormal LVEF or cardiac dilatation by chest x-ray or echocardiography. Radionuclide LVEF was obtained at baseline, within 6 months, and at least yearly after randomization to treatment. Cumulative survival subsequent to LVEF follow-up measurements was calculated for strata defined by LVEF change from baseline. In V-HeFT I, patients treated with hydralazine/isosorbide dinitrate (H-I) experienced a significant (p < 0.001) increase in LVEF and a survival advantage over those treated with placebo and prazosin. In V-HeFT II, both treatment groups showed significant improvements in LVEF, with the increase with H-I greater than that with enalapril, and enalapril provided a significant survival advantage over H-I. Change (> 5) in LVEF from baseline at 6 months (V-HeFT I) and 1 year (V-HeFT II) were the strongest predictors of mortality among the serial measurements and were significant after adjustment for therapy and baseline LVEF. Baseline clinical variables were not helpful in predicting the patients who would experience an improvement in LVEF.
In patients with heart failure, serial measurements of LVEF provide additional important prognostic information. Vasodilator therapy with H-I is associated with an improvement in LVEF and prognosis. Vasodilator therapy with enalapril improves LVEF less than H-I but provides an additional survival benefit.