Carotid artery distensibility and distending pressure in hypertensive humans.

Abstract

Whether the decrease in large-artery distensibility observed in hypertensive patients is due primarily to an increase in distending pressure or to hypertension-induced changes in structural properties has been much debated. We determined noninvasively the diameter-pressure curve of the common carotid artery over the systolic-diastolic range by continuously recording both the pulsatile changes in internal diameter (high-resolution echo-tracking system) and, simultaneously on the contralateral artery, the pressure waveform (high-fidelity applanation tonometry). We then derived the distensibility/pressure curve and compared arterial distensibility in 14 normotensive subjects and 15 age-and sex-matched hypertensive subjects at their respective mean arterial pressures (MAP) and at a common distending pressure: 100 mm Hg. Distensibility decreased as blood pressure increased, and distensibility at MAP was significantly lower in hypertensive than in normotensive subjects (7.8±0.7 versus 11.7±1.7 kPa"'-10" 3 , mean±SEM; P<.05). In hypertensive subjects,

A longitudinal study of vessel wall properties in normotensive and hypertensive renal transplant recipients

“…2,11 Recent studies indicate that differences in distending pressure account for arterial stiffness in essential hypertension. 18,19 Laurent et al 19 have shown that the decrease in arterial distensibility was primarily due to higher distending BP rather than to structural modifications, and when adjusted for differences in BP, hypertrophied arteries of essential hypertensive subjects were more distensible than those of normotensive controls. In contrast to the results in essential hypertensive subjects, arterial stiffness in hypertensive patients with end-stage renal failure appear to be related to structural vessel wall changes.…”

Structural and Genetic Bases of Arterial Stiffness

“…Carotid stiffness can be determined directly from the ratio of local PP (measured by applanation tonometry) to relative stroke change in diameter (measured by ultrasound scan). 11 Aortic stiffness can be estimated indirectly from augmentation index (AIx). 12 AIx is the extra pressure caused by pressure wave reflection back from the periphery.…”

Carotid Intimal-Medial Thickness and Stiffness Are Not Affected by Hypercholesterolemia in Uncomplicated Essential Hypertension

“…The evidence for altered arterial stiffness in hypertensive patients when the pressure-sensitive augmentation index was used but not with the pressure-insensitive stiffness index is in accordance with previous reports that did not detect an impact of hypertension on arterial stiffness evaluated at a standardized pressure level. 47,48 Although studies in hypercholesterolemic animals indicated increased arterial stiffness, 20,21 results may have been affected by use of the pressure-dependent pulse wave velocity as the index of vascular stiffness. Other human observations did not detect reduced arterial compliance in nonfamilial hypercholesterolemia 49 or an effect of high cholesterol levels on age-related increases in arterial stiffness.…”