Background: Heart failure therapy with beta-receptor blockade has been shown to effect a partial reversal of left ventricular (LV) remodeling in heart failure.
Hypothesis: We tested the hypothesis that, in the absence of beta blockade, uptitration of angiotensin-converting enzyme (ACE) inhibitor and nitrate therapy over conventional dosages would improve symptoms as well as LV function in patients with severe heart failure.
Methods: For patients with nonischemic or ischemic cardiomyopathy, intensive high-dose angiotensin-converting enzyme inhibitor and nitrate therapy was uptitrated. Echocardiograms were obtained semiannually and evaluated in a blinded fashion. Of 99 patients in the study, aged 55 +/- 13 years, with heart failure for 5.2 +/- 3.1 years, 74 were men, 69 were Caucasian, and 34 had ischemic cardiomyopathy. The final dosage of enalapril was 40 +/- 23 mg/day of isosorbide dinitrate it was 153 +/- 127 mg/day.
Results: Initial New York Heart Association classification improved from 2.8 +/- 0.9 to 1.7 +/- 0.9 (p < 0.001) in 2.7 years of follow-up. Of the 99 patients, 72 further improved their ejection fraction. For the whole group, ejection fraction increased from 21 +/- 9% to 30 +/- 13% in 6 months (p < 0.001), with a reduction in LV end-diastolic size from 6.6 +/- 0.9 to 6.3 +/- 1.0 cm (p = 0.002), a decrease in the severity of mitral regurgitation from mild/moderate to only mild. Resting heart rate declined with no change over time in systemic systolic blood pressure. Final ejection fraction for nonischemic patients (n = 65) was 36 +/- 16% versus 23 +/- 9% for the ischemic population.
Conclusions: Uptitration of high-dose ACE inhibitor and nitrate therapy to higher doses is well tolerated in severe heart failure, further improves both clinical status and LV systolic function, and is more effective in nonischemic than in ischemic cardiomyopathy.