The presence of coronary artery calcium (CAC) was significantly associated with higher atherosclerotic cardiovascular disease (CVD) event rates, according to a study to be published in Journal of the American College of Cardiology: Cardiovascular Imaging. Despite diagnoses of molecularly proven heterozygous familial hypercholesterolemia, no events occurred in patients without CAC on standard lipid lowering therapy.
These findings suggest that there is a potential for advanced risk stratification and allocation for more aggressive lipid lowering therapies in this population.
Patients with mutations on the low-density lipoprotein receptor gene (n=206, age 45±14 years) and baseline and on-treatment levels of low-density lipoprotein cholesterol of 269±70 and 150±56 mg/dL, respectively, were followed for a median of 3.7 (quartiles: 2.7-6.8) years.
A total of 101 patients (49%) had CAC 0, but 62 patients (30%) had CAC 1-100, and 43 (21%) had CAC >100. Distribution of age across CAC groups was heterogeneous; patients with familial hypercholesterolemia with mild and moderate CAC were significantly older than patients with CAC 0; 19% of patients with CAC 0 were >50 years of age, and 16.2% of patients with CAC >100 were younger than 50.
At follow-up, 15 (7.2%) major atherosclerotic cardiovascular events were observed, representing 16.6 events per 1000 person-years. Nearly half (46.6%) of the events were hard end points, including 3 nonfatal and 2 fatal myocardial infarctions, 1 unstable angina requiring revascularization, and 1 fatal stroke; others were elective myocardial revascularizations.
CAC testing may aid in decisions concerning where proprotein convertase subtilisin kexin type 9 inhibitors may derive the highest yield, particularly in consideration of constrained healthcare resources and costs.
This study had several limitations but nevertheless allowed for meaningful results, and limitations must be evaluated within the context of the study design. With its limited sample size, the study might have limited power for precise estimations, but the results are robust. Future studies should focus on longer-term follow-ups with a larger sample size.
Disclosures: Multiple authors declared affiliations with the pharmaceutical industry. Please refer to reference for a complete list of authors’ disclosures.
Miname MH, Sommer Bittencourt M, Moraes SR, et al. Coronary artery calcium and cardiovascular events in familial hypercholesterolemia patients undergoing standard lipid lowering therapy [published online November 14, 2018]. JACC Cardiovasc Imaging. doi: 10.1016/j.jcmg.2018.09.019