EFFECT OF ANGIOTENSIN-CONVERTING ENZYME-INHIBITION ON PLASMA ENDOTHELIN IN CONGESTIVE-HEART-FAILURE

The influence of angiotensin converting enzyme inhibitor therapy on el evated plasma endothelin concentrations in chronic heart failure was i nvestigated by measuring plasma endothelin immunoreactivity in 22 pati ents with severe but stable chronic heart failure before and after 16 weeks of therapy with quinapril (n = 12) or captopril (n = 10). Plasma endothelin immunoreactivity in the patients (10.2 +/- 34 pg/ml) was s ignificantly higher than a control group (5.9 +/- 1.8 pg/ml). Quinapri l improved symptoms and haemodynamics but did not affect plasma endoth elin immunoreactivity (11.9 +/- 2.9 pg/ml at baseline and 12.3 +/- 3.4 pg/ml after 16 weeks of quinapril). Captopril also had no effect on e ndothelin levels (8.1 +/- 2.9 at baseline and 8.1 +/- 3.8 pg/ml after 16 weeks of captopril). The vasodilatory effects of angiotensin conver ting enzyme inhibitors in heart failure are not mediated by, or associ ated with, changes in plasma endothelin immunoreactivity.