Enalapril improved ejection fraction (p<0.05) and lowered aldosterone (p<0.05) in heart failure patients, but did not improve exercise capacity or peak VO2.
The effects of enalapril on exercise capacity and neurohumoral factors during exercise were evaluated in 10 patients with heart failure. Echocardiograms and exercise testing with expired gas analysis were performed before and after enalapril. Blood samples were obtained before and after exercise. Both ejection fraction and percent fractional shortening increased with enalapril (p < 0.05). The anaerobic threshold and peak VO2 did not change with enalapril. Epinephrine and norepinephrine levels at peak exercise decreased with enalapril (p < 0.1). Plasma renin both at rest and at peak exercise increased with enalapril (p < 0.1). Angiotensin II was lower after enalapril both at rest and at peak exercise (p < 0.1 and p < 0.05, respectively). Aldosterone was lower after enalapril both at rest and at peak exercise (p < 0.05). Atrial natriuretic peptide (ANP) was lower after enalapril both at rest and at peak exercise. There was no significant correlations between peak VO2 and changes in neurohumoral factors before and after enalapril during exercise. In conclusion, neurohumoral changes with enalapril occurred during exercise even if exercise capacity did not improve. Moreover, the improvement of cardiac function at rest and neurohumoral factors with enalapril did not lead to a change of exercise capacity.
Oginö et al. (2008) studied Chronic Heart Failure (n=10). Enalapril vs. Baseline (before enalapril) was evaluated on Exercise capacity and neurohumoral factors during exercise. Enalapril improved ejection fraction (p<0.05) and lowered aldosterone (p<0.05) in heart failure patients, but did not improve exercise capacity or peak VO2.