Atorvastatin Treatment Improves Myocardial and Peripheral Blood Flow in Familial Hypercholesterolemia Subjects without Evidence of Coronary Atherosclerosis

BACKGROUND: Hypercholesterolemia induces early microcirculatory functional and structural alterations that are reversible by cholesterol reduction. Real time myocardial contrast echocardiography (RTMCE) and vascular ultrasound evaluate the effects of hyperlipidemia on peripheral and central blood flow reserve. This study investigated the effects of lipid-lowering therapy on coronary and peripheral artery circulation in patients with familial hypercholesterolemia (FH). METHODS: RTMCE and vascular ultrasound were performed in 10 healthy volunteers (validation group) at baseline and after 12-week clinical observation, and in 16 age- and sex-matched FH patients without obstructive coronary artery disease (CAD) by computed tomography angiography at baseline and after 12-week atorvastatin treatment. Indexes of relative myocardial blood flow (MBF) were obtained at rest and during adenosine infusion. RESULTS: In validation group, there was no significant difference between flow-mediated dilation (FMD) at baseline and after 12 weeks (0.15 ± 0.02 vs. 0.14 ± 0.03; P = 0.39). Similarly, no differences were observed in MBF reserve at baseline and after 12 weeks (3.31 ± 0.63 vs. 3.48 ± 0.89; P = 0.89). FMD was blunted in FH patients, at baseline, as compared with validation group (0.08 ± 0.04 vs. 0.15 ± 0.02; P < 0.001) and became similar to that group (0.13 ± 0.05 vs. 0.14 ± 0.03; P = 0.07) after treatment. MBF reserve was blunted at baseline in FH patients in comparison with the validation group (2.78 ± 0.71 vs. 3.31 ± 0.63; P = 0.003). After treatment, MBF reserve values were no longer different (3.43 ± 0.66 and 3.48 ± 0.89; P = 0.84, respectively, for FH and validation groups). CONCLUSION: Patients with FH and no obstructive CAD have blunted MBF reserve and lower FMD values as compared with healthy volunteers. Both FMD and MBF reserve were normalized after atorvastatin treatment.