Quantitative 3T MR Imaging of the Descending Thoracic Aorta: Patients with Familial Hypercholesterolemia Have an Increased Aortic Plaque Burden Despite Long-Term Lipid-lowering Therapy

Abstract

To compare the aortic plaque burden in patients with heterozygous familial hypercholesterolemia on long-term statin treatment with that of matched control subjects. The authors studied 11 heterozygous, nonsmoking, nondiabetic, and nonhypertensive patients with familial hypercholesterolemia (mean age, 44 years +/- 10) who had been receiving cholesterol-lowering management for a mean of 12 years +/- 5, including 8.25 years +/- 4.24 with the highest tolerable doses of a statin (or a statin plus ezetimibe), and 26 age- and sex-matched control subjects with 3T magnetic resonance (MR) imaging of the descending thoracic aorta by using an axial T2-weighted turbo spin-echo sequence. Quantitative analysis demonstrated that the aortic vessel wall area was significantly larger in patients with familial hypercholesterolemia than in control subjects (123 mm(2) +/- 23 vs 102 mm(2) +/- 18, respectively; P < .007), as was vessel wall thickness (1.63 mm +/- 0.28 vs 1.37 mm +/- 0.16, respectively; P < .001). No significant difference was found between mean values of routine serum lipid and lipoprotein parameters. The results of this preliminary study show that patients with heterozygous familial hypercholesterolemia have a higher aortic atherosclerotic plaque burden than control subjects at quantitative MR imaging despite long-term lipid-lowering therapy. This information may help design future studies evaluating plaque burden and cardiovascular risk.