Non-invasive ultrasound detection of endothelial dysfunction.

With high resolution ultrasound we assessed endothelial function in subjects at risk of atherosclerosis. We used ACUSON 128XP/10 system with 7.0 MHz linear array transducer. Three groups of patients (pts) were studied: 12 patients with essential hypertension, ten patients with 2A familial hyperholesterolamia and ten controls without vascular risk factors. We measured the diameter of brachial artery at rest, during reactive hyperaemia (with increased flow causing endothelium-dependent dilation), and after sublingual 0.01 mg nitroglycerin (causing endothelium-independent dilation). Flow-mediated dilation is not impaired in essential hypertension (9. 4%) compared with controls (9.5%) and impaired in patients with familial hyperholesterolaemia (3.0%). NTG-induced dilation is not impaired in familial hyperholesterolaemia (16.6%) and essential hypertension (14.5%) compared with controls (20.5%). The effect of hypolipidaemic influence (probucol and plasmapheresis) was assessed in a separate study. These results demonstrate the capability of ultrasound in detection of endothelial dysfunction, and suggest that endothelial dysfunction in patients with familial hyperholesterolaemia is one of the risk factors for atherosclerosis. The parameters of endothelial function may be used as markers of hypolipidemic influence on patients with hyperholesterolaemia.