Relationship between carotid wall thickness and forearm blood flow reserve in hypertension

The development of a reduced forearm blood flow reserve and an increased carotid intima media thickness is a well known consequence of the structural adaptation of arterioles and large arteries in response to hypertension. It is unknown, however, how those two processes relate to each other in the individual hypertensive patient.

Minimal forearm vascular resistances (Rmin, the ratio of mean blood pressure to postischemic plethysmographic peak forearm blood flow), common carotid intima media thickness (IMT, high-resolution ultrasonography), blood pressure (indirect method), left ventricular mass, posterior wall and septum thickness (by echocardiography) and lipids were measured in 15 men with mild-to-moderate essential hypertension without evidence of atherosclerotic involvement of the carotid arteries, and in 14 normotensive controls with a similar age range.

Rmin and IMT were greater in hypertensives, and a statistically significant positive correlation existed between the two variables. Both Rmin and IMT correlated with left ventricular structure indices and blood pressure. Age showed a positive correlation with IMT, while lipids were unrelated to either parameter.

The micro- and macrovascular segments of the hypertensive circulation readapt in parallel in response to elevated blood pressure, possibly through the commensurate development of medial hypertrophy.