Correlation of coronary and carotid atheroma volume in patients with severe and familial hypercholesterolemia (VOCCA-3D HF)

Abstract Background Stratifying the risk of CV event of familial hypercholesterolemia (FH) patients is not always simple, as they usually are excluded from CV disease risk estimation scores. It has become increasingly clear over the last several years that the heterogeneity in risk among patients with FH is far greater than previously appreciated. To that end, not all patients with FH will require the use of PCSK9 inhibitors. Aim We described the type of coronary artery disease (CAD) in patients with severe and familial hypercholesterolemia and without known atherosclerotic cardiovascular disease and searched for the best determinants of CAD. We searched for correlation between epicardial adipose tissue and CAD. Methods We evaluated the atherosclerosis burden with a combination of calcium score (CAC), computed tomography angiography, and the quantification of coronary atheroma volume and the analysis of the composition of the plaques, alongside with the use of ultrasonography of supra-aortic trunks with 3D quantification of atheroma volume. We also evaluated epicardial adipose tissue volume with CT. Results We analyzed 89 individuals with LDL-c > 190 mg/dL, with a mean age of 56,7 years. LDL-c burden was high (maximal LDL-c level across life of 2.77 g/L in mean, duration of hypercholesterolemia of 21.5 years in mean). Forty percent of the individuals had a CAC score of zero, and only one patient had non-calcified atheroma despite a CAC score of zero. Among patients with CAD, 50% had a CAC > 100 AU, 9% had a stenosis > 50%. Coronary atheroma volume amounted to a median of 50.9 mm3 in patients with CAD, representing 4% of the analyzed coronary lumen volume, and was mainly made of calcified and non-calcified fibrous plaques. At-risk plaques were not frequent (9% of low-attenuation plaques, 15.2% of positive remodeling and 2% of napkin-ring sign) in patients with CAD. Fifty percent of the individuals had no carotid plaque. Among various clinical and biological risk factors (LDL-year-score, age, blood pressure, smoking, familial history, diabetes), the carotid atheroma volume was the only variable to be independently correlated with both CAC (t=3.1, p=0.006) and coronary atheroma volume (t=4.9, p<0.001). Epicardial adipose tissue was not associated with CAD. Conclusion A significant part of the patients with severe and familial hypercholesterolemia has no CAD, however half of the patients with CAD have an important atherosclerosis burden, which can be well predicted by the carotid atheroma volume. Such a screening could help identify the individuals who would benefit the most from intensive cholesterol-lowering drugs.CAC categoriesType of coronary plaques