A COMPARATIVE-STUDY OF CAPTOPRIL AND ENALAPRIL ON ENDOTHELIAL-CELL FUNCTION IN CONGESTIVE-HEART-FAILURE PATIENTS

Angiotensin-converting enzyme (ACE) inhibitors have been shown to redu ce the incidence of future coronary artery thromboses in postmyocardia l infarction patients. A possible prothrombotic role for the angiotens in system has been postulated, and support for this has been provided by a recent study that demonstrated that an infusion of angiotensin in creases levels of the prothrombotic plasminogen activator inhibitor (P AT). In the current study the authors have investigated the effect of two ACE inhibitors, captopril and enalapril, on tissue plasminogen act ivator (tPA) and PAI in 33 congestive heart failure (CHF) patients. Bl ood samples were obtained pretreatment and then at weeks 1, 12, and 24 after initiation of ACE inhibitor therapy for measurement of tPA anti gen and PAI activity levels. The results of the study indicated that t he initiation of ACE inhibitors had no significant effects on tPA anti gen or PAI activity levels at the time points studied, and no signific ant differences were demonstrated between captopril and enalapril. The results suggest, therefore, that ACE inhibitors do not affect tPA ant igen or PAI activity in CHF patients, and thus another mechanism is pr obably responsible for the observed decrease in coronary artery thromb oses in post-MI patients treated with ACE inhibitors.