DYNAMIC EXERCISE INDUCES ELEVATION OF PLASMA-LEVELS OF ENDOTHELIN-1 IN PATIENTS WITH CORONARY-ARTERY DISEASE

In this investigation the response of endothelin-l plasma levels to dy namic exercise in patients with coronary artery disease (CAD) was stud ied. The study population consisted of 20 patients with CAD, 16 men an d 4 women (mean age 53 +/- 8.6 years). Seven normal volunteers all men (mean age 53.4 +/- 4.4 years) were studied as a control group. Seven patients had prior myocardial infarction. All patients and controls ex ercised on a multistage bicycle ergometer; plasma endothelin-1 levels and hemodynamic indices were measured at rest, at peak exercise, and a t two and six minutes after exercise. Of the 20 patients examined, 7 ( 35%) showed electrocardiographic (EGG) signs of myocardial ischemia du ring the stress test. The mean plasma endothelin-l concentration incre ased significantly from 7.8 +/- 3.0 to 13.6 +/- 3.5 pg/mL at exercise peak (P < 0.05) only in patients who did not show ECG signs of myocard ial ischemia and returned to baseline values during recovery (six minu tes) (9.4 +/- 2.1 pg/mL). In normal subjects baseline endothelin-l lev els (9.4 +/- 4.2 pg/mL) were not significantly altered at peak exercis e (10.8 +/- 4.7 pg/mL) and at recovery (11.3 +/- 3.6 pg/mL). The hemod ynamic parameters were not correlated with the plasma endothelin-l lev els before, during, and after exercise in all groups. The present stud y demonstrated that the plasma levels of endothelin-1 in patients with CAD increased significantly during stress testing.