Background: In uncomplicated hypertensive patients the prognostic role of endothelial dysfunction, as evaluated by flow-mediated vasodilatation of the brachial artery, has not been investigated.

Methods: A total of 175 prospectively identified uncomplicated hypertensives (age 53±5 years, 42% women, 48 with diabetes mellitus type 2) were studied. At baseline all subjects were untreated and underwent a baseline standard laboratory examinations. A standard echocardiogram was performed for the evaluation of LV anatomy and function and patients with systolic dysfunction or LV wall motion abnormalities were excluded. Endothelial function was measured as flow-mediated dilation of the brachial artery using highresolution ultrasound.

Results: Patients were followed for 86±34 months (range 11–123 months). A first non fatal or fatal cardiovascular event occurred in 28 patients. The incidence of cardiovascular events was 1.4 and 3.1 per 100 patient-years in patients with a FMD above (n = 87) and below (n = 88) the median value, respectively (p < 0.005 by the log-rank test). In Cox analysis, controlling for age, gender, diabetes, hypercholesterolemia, smoking, and systolic BP at baseline, a low FMD conferred an increased risk of cardiovascular events (odds ratio 2.27, 95% confidence interval [CI] 1.01–5.15, p < 0.001).

Conclusions: The presence of endothelial dysfunction, as evaluated by flow-mediated vasodilatation of the brachial artery, identifies hypertensive patients at increased risk of non fatal and fatal cardiovascular events.