👤 Michael Gurevitz

Lipoprotein(a) [Lp(a)] is an inherited cardiovascular risk factor. However, its association with coronary plaque characteristics beyond traditional risk enhancers remains unclear. We aimed to evaluate the association between Lp(a) levels and coronary plaque characteristics in asymptomatic primary prevention patients, and to compare its predictive value against other risk enhancers, including LDL particle concentration (LDL-P), high-sensitivity C-reactive protein (hsCRP), and coronary artery calcium (CAC) score. We retrospectively analyzed 547 asymptomatic patients undergoing coronary computed tomography angiography (CCTA) between 2018-2024. Plaque characteristics were assessed using artificial intelligence-based quantitative CCTA. Associations between Lp(a), LDL-P, hsCRP, CAC score, and plaque features were evaluated using multivariable regression adjusted for age and sex. Median age was 56 years, 69.8% were male. Higher Lp(a) was associated with greater total plaque volume (β=23.1 mm³, p=0.006), calcified plaque (β=11.1 mm³, p=0.014), non-calcified plaque (β=12.0 mm³, p=0.027), and low-density non-calcified plaque (LDNCP; β=0.4 mm³, p<0.001) volumes, as well as increased area stenosis (β=1.9%, p=0.031) and remodeling index (β=0.02, p=0.017). In multivariable models, CAC score was the strongest predictor of overall plaque burden including calcified and non-calcified plaque (p<0.000) but was not associated with LDNCP. Lp(a) remained independently associated with LDNCP (β=0.45 mm³, p=0.013), while LDL-P and hsCRP showed no significant associations. In asymptomatic primary prevention patients, Lp(a) was independently associated with high-risk coronary plaque features, specifically LDNCP, beyond traditional risk enhancers. These findings highlight the unique role of Lp(a) in identifying coronary plaque vulnerability and suggest complementary roles for Lp(a) and CAC in refining cardiovascular risk stratification. Show less

The development of tendinous xanthomas in childhood with a low-density lipoprotein (LDL) cholesterol level >400 mg/dL is characteristic of homozygous familial hypercholesterolemia (FH). We present the case of a patient with a severely elevated LDL cholesterol level and childhood-onset xanthomas who fulfilled clinical criteria for homozygous FH. However, genetic and absorption testing clarified his phenotype to be a unique digenic overlap of both heterozygous FH and heterozygous sitosterolemia with marked elevations in cholesterol absorption indices. Treatment with ezetimibe 10 mg daily resulted in a dramatic reduction in LDL cholesterol. Sitosterolemia, a rare autosomal recessive disorder of plant sterol hyperabsorption, can also result in xanthomatosis and thus can mimic FH. Although it is usually a homozygous disease, heterozygotes may exhibit intermediary phenotypes. Patients with severe hypercholesterolemia should undergo genetic and biochemical profiling for diagnostic confirmation and for ensuring that they receive optimal, personalized therapy. Show less