Radial artery compliance in response to mental stress in normotensive offspring of hypertensive parents

Objectives: Compared to normal subjects hypertensive patients have an incre ased radial artery isobaric distensibility, contrasting with a decrease in elasticity of large arteries and systemic compliance. To address the questi on whether elasticity is increased in response to long-standing elevated bl ood pressure or is present at an early stage of the disease, we compared no rmotensive offspring of hypertensive parents with control subjects. Further more, enhanced sympathetic response to mental stress was demonstrated in in dividuals predisposed to hypertension and might contribute to the elevation of blood pressure via a peripheral mechanism. Thus, an abnormal vasoconstr ictive response of the radial artery to psychological stress was sought in these subjects. Design: The geometry and the elastic porperties of the radial artery were a ssessed in normotensive offspring of hypertensive and normotensiven parents at baseline and during mental stress. Methods: A high-precision echo-tracking ultrasound device was combined with photoplethysmography for continuous measurement of radial artery diameter and isobaric distensibility in 18 normotensive offspring of parents with es sential hypertension and 18 control subjects under resting conditions and d uring a 3-minute mental stress test. Results: Baseline arterial distensibility and compliance were comparable in offspring of hypertensive and normotensive parents. During mental stress, blood pressure and heart rate increased similarly in both groups. Adrenergi c activation did not alter the elastic properties of the radial artery in t he individuals with a genetic predisposition to essential hypertension. Conclusions: There was no alteration in elastic properties of the radial ar tery in normotensiven individuals at genetic risk to develop arterial hyper tension. Furthermore, mental stress did not abnormally increase the vascula r tone of this medium-sized muscular artery in these subjects as compared t o controls. This indicates that functional and/or structural vascular alter ations do not precede a distinct rise in blood pressure or abnormal blood p ressure reactivity in subjects prone to develop essential hypertension.