Assessment of microvascular function and pharmacological regulation in genetically confirmed familial hypercholesterolemia.

BACKGROUND

Familial hypercholesterolemia (FH) is a genetic lipid disorder leading to accelerated atherosclerosis, premature cardiovascular disease and death. Microvascular endothelial dysfunction is one of the earliest vascular pathology manifestations and may precede symptomatic atherosclerosis.

METHODS

In this paper, microvascular endothelial function was assessed in FH patients and healthy controls using flow mediated skin fluorescence (FMSF), based on measurements of nicotinamide adenine dinucleotide fluorescence intensity during brachial artery occlusion (ischemic response, IR) and immediately after occlusion (hyperemic response, HR). Low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC) were used to assess its relation with microvascular parameters evaluated in vivo.

RESULTS

LDL-C levels were significantly correlated to both HR (r = -0.548, p = 0.001) and HR (r = -0.514, p = 0.003). Similarly, there was a significant inverse correlation of TC levels and both HR (r = -0.538, p = 0.002) and HR (r = -0.512, p = 0.003). All FMSF parameters were found lower in FH patients compared to age- and sex-matched healthy controls. Hyperemic response (HR) was significantly higher in FH patients examined on statins compared to those without any lipid-lowering treatment (19.9 ± 3.1 vs. 16.4 ± 4.2 respectively, p = 0.022).

CONCLUSIONS

This study shows that, in patients with FH, microvascular endothelial-dependent hyperemic response is impaired and inversely correlated to plasma cholesterol levels. Microvascular function was found better in FH patients receiving statins.