EFFECTS OF ENALAPRIL ON THE EXERCISE CAPACITY AND NEUROHUMORAL FACTORS DURING EXERCISE IN PATIENTS WITH CHRONIC HEART-FAILURE

The effects of enalapril on exercise capacity and neurohumoral factors during exercise were evaluted in 10 patients with heart failure. Echo cardiograms and exercise testing with expired gas analysis were perfor med before and after enalapril. Blood samples were obtained before and after exercise. Both ejection fraction and percent fractional shorten ing increased with enalapril (p < 0.05). The anaerobic threshold and p eak V-o2 did not change with enalapril. Epinephrine and norepinephrine levels at peak exercise decreased with enalapril (p <0.1). Plasma ren in 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 ex ercise (p <0.1 and p <0.05, respectively). Aldosterone was lower after enalapril both at rest and at peak exercise (p <0.05). Atrial natriur etic peptide (ANP) was lower after enalapril both at rest and at peak exercise. There was no significant correlations between peak V-o2 and changes in neurohumoral factors before and after enalapril during exer cise. In conclusion, neurohumoral changes with enalapril occurred duri ng exercise even if exercise capacity did not improve. Moreover, the i mprovement of cardiac function at rest and neurohumoral factors with e nalapril did not lead to a change of exercise capacity.