Treatment of essential arterial hypertension with enalapril does not result in normalization of endothelial dysfunction of the conduit arteries

It is assumed that endothelial dysfunction due to arterial hypertension could be improved or even normalized by antihypertensive treatment. The present study was designed to explore that assumption in patients with essential hypertension treated with an angiotensin-converting enzyme (ACE) inhibitor-enalapril. Twenty-eight patients (mean age: 55.1 years) who fulfilled the following criteria were included: essential arterial hypertension present for more than 2 years, monotherapy with enalapril for at least I year, adequate treatment (blood pressure in the last year < 140/90 mm Hg) and absence of other factors (smoking, hypercholesterolemia, diabetes, obesity), which could importantly influence endothelial function. The flow-mediated (endothelium-dependent) dilation (FMD) of the brachial artery was assessed by high-resolution ultrasound and compared with that of 22 age-matched healthy normotensive controls. The patients and controls did not differ in regard to body mass index, lipids, and plasma glucose and insulin; there were no smokers. FMD of the brachial artery was significantly decreased in patients in comparison to controls (7.9% vs 13.5%, p < 0.01). FMD in patients was inversely correlated with the duration of hypertension (r = -0.52, p < 0.01) and with both systolic (r=-0.72, p < 0.01) and diastolic (r=-0.43, p < 0.05) blood pressure (measured after temporary withdrawal of treatment). This study showed that the adequate control of blood pressure achieved with enalapril is not followed by normalization of endothelial function, measured by FMD of the brachial artery.