Effect of antihypertensive therapy using enalapril or losartan on haemostatic markers in essential hypertension: a pilot prospective randomised double-blind parallel group trial.

To test the hypothesis that the hypercoagulable state in hypertension is significantly altered by anti-hypertensive therapy, we conducted a pilot prospective randomised double-blind trial of 40 untreated hypertensive patients (30 males, mean age 59 years) who were treated with either enalapril (10-20 mg per day) or losartan (50-100 mg per day) for 8 weeks. Thrombogenicity was assessed by measurement of plasma fibrinogen, soluble P-selectin (an index of platelet activation), plasminogen activator inhibitor 1 (PAI-1, an index of fibrinolysis) and von Willebrand factor (an index of endothelial dysfunction). Baseline von Willebrand factor alone was significantly higher in untreated hypertensive patients compared to controls (P