Carotid distension and distensibility impairment in individuals affected by familial combined hyperlipidemia

Objective: To investigate whether individuals affected by familial combined hyperlipidemia, a common lipid disorder increasing the cardiovascular risk, had different carotid ultrasound parameters compared to control subjects without this family disorders. Methods: 127 cases and 127 controls matched for age and gender were enrolled. Serum glucose, total cholesterol, high-density lipoprotein-cholesterol, triglycerides, ApoB, insulinemia were measured by standard laboratory techniques. All the subjects underwent B-mode ultrasonography to measure the end-diastolic and end-systolic diameter of the common carotid artery and, successively, to calculate distensibility, compliance, Young's elastic modulus and distension. Results: Carotid diameter and Young's elastic modulus were significantly greater among FCH subjects than among controls, and carotid distensibility, compliance, distension and score distension were significantly lower than control, also after analysis of covariance in order to adjust all the carotid indexes for confounding variables. A multiple regression analysis confirmed that familial combined hyperlipidemia status was correlated to carotid indexes. In a model including the lipid parameters, triglycerides was the only lipid variable correlated with distensibility but not with distension. Conclusion: This hyperlipidemia, particularly hypertrigliceridemia, could be the direct responsibility of carotid modification leading to the impairment of the distension/distensibility that, in turn, makes the patients prone to atherosclerosis.