Intrinsic modifications of the brachial and radial arteries in hypertensive humans.

The properties of vessel walls of brachial and radial arteries were studied noninvasively, using 2 original pulsed ultrasound echo-tracking systems based on Doppler shift, in an investigation comparing 32 normotensive controls and 50 age-matched hypertensive patients. The 2 groups did not differ with respect to sex, total and high-density lipoprotein cholesterol, blood glucose, and smoking habits. Whereas noninvasive measurements of blood pressure indicated that both mean arterial pressure and pulse pressure were significantly increased in the arterial tree of the hypertensive forearm, end-diastolic diameter and pulsatile changes of the brachial and radial arteries remained within the normal range. The finding was more pronounced at the site of the radial artery in which: (i) pulsatile changes of blood pressure (documented from Finapres method) were significantly higher than those of the brachial artery, yet (ii) indices of arterial stiffness (compliance and distensibility) remained within the normal range. For the branchial artery, distensibility was significantly reduced (p = 0.01), whereas no significant change in compliance was observed. The study provides evidence that, in subjects with essential hypertension, the mechanical properties of the brachial and the radial arteries are not exclusively related to the level of blood pressure, and differ according to the arterial segment studied.