Prognostic role of flow-mediated dilatation of the brachial artery in hypertensive patients.

Background: The prognostic role of endothelial dysfunction, as evaluated by flow-mediated vasodilatation of the brachial artery, has been demonstrated in patients at very high risk. We aimed to investigate whether flow-mediated vasodilatation predicts cardiovascular events in uncomplicated hypertensive patients.

Methods And Results: A total of 172 prospectively identified uncomplicated hypertensive patients (age 56 +/- 8 years, 41% women, 48 with diabetes mellitus type 2) were studied. At baseline all patients were untreated and underwent baseline standard laboratory examination. A standard echocardiogram was performed for the evaluation of left ventricular anatomy and function and patients with systolic dysfunction or left ventricular wall motion abnormalities were excluded. Endothelial function was measured as flow-mediated vasodilatation of the brachial artery using high-resolution ultrasound. Patients were followed for 95 +/- 37 months (range 2-136 months). A first nonfatal or fatal cardiovascular event occurred in 32 patients. The incidence of cardiovascular events was 1.4 and 3.1 per 100 patient-years in patients with a flow-mediated vasodilatation below and above the median value (4.7%), respectively (P < 0.005 by the log-rank test). In Cox analysis, controlling for age, sex, glycemia, cholesterol, smoking, BMI, systolic and diastolic blood pressure at baseline and left ventricular mass index, a low flow-mediated vasodilatation conferred an increased risk of cardiovascular events (odds ratio 2.67, 95% confidence interval 1.17 to 6.1, P = 0.02).

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