Effect of ACE inhibition on the fibrinolytic system in patients requiring coronary artery bypass grafting.

BACKGROUND: Regulation of the fibrinolytic balance between plasminogen activators and inhibitors is modulated by the renin-angiotensin system. Thus, alterations in the renin-angiotensin system by ACE inhibitors probably result in modification of the fibrinolytic system. We examined the effect of a short-term treatment with the ACE inhibitor enalapril in 47 patients with severe coronary artery disease requiring coronary artery bypass grafting (CABG). METHODS: Patients received either 20 mg/d enalapril or placebo for 6 days. Tissue-type plasminogen activator (TPA), plasminogen activator inhibitor-1 (PAI-1), plasmin-a2-antiplasmin-complex (PAP) and D-dimers were measured initially and after treatment. RESULTS: In the enalapril group PAI-1 levels were significantly reduced after treatment (11.9 +/- 2.3 U/ml vs. 17.1 +/- 3.0 U/l; P < 0.05). In the placebo group PAP levels were significantly higher ( P < 0.05) after treatment compared to initial values. No differences could be detected between the study groups with regard to TPA and D-dimers. CONCLUSION: Although PAI-1 activity levels are reduced after short-term treatment with ACE inhibitors in patients with stable angina pectoris while TPA antigen is unaffected, treatment with ACE inhibitors does not lead to a marked change in plasmin activation.