Femoral vs Carotid Plaque Screening for Coronary Artery Disease Risk

Femoral plaque vs carotid plaque screening may better predict coronary artery disease, according to results from the Aragon Workers’ Health Study (AWHS), published in the Journal of the American College of Cardiology.

Carotid arteries have been the main focus of research on early subclinical atherosclerosis. To investigate the potential value of femoral arteries for coronary artery calcium score (CACS) prediction, researchers of the present study compared the association of subclinical femoral and carotid plaques with risk factors, including dyslipidemia, smoking status, hypertension, diabetes, and age, and CACS in a cohort of middle-aged men.

“The most important findings of the present study are that subclinical atherosclerosis in an otherwise healthy middle-aged male cohort is most likely identifiable in femoral arteries, that femoral atherosclerosis shows the strongest association with cardiovascular risk factors, and that femoral plaques show a higher sensitivity than carotid plaques for the presence of calcified coronary disease (CACS ≥1 or ≥300),” the authors wrote.

A total of 1423 middle-aged men, between 40 and 59 years of age, were included in the study. Participants underwent carotid and femoral artery ultrasound with noncontrast coronary computed tomography.

Researchers defined subclinical atherosclerosis as the presence of any plaque in carotid or femoral arteries, or a CACS ≥1. They used logistic regression models to estimate the prevalence of atherosclerosis, evaluate the association of atherosclerosis with risk factors, and calculate areas under the receiver-operating characteristic curves for the presence of positive CACS.

They found subclinical atherosclerosis in 72% of the participants. Plaque was most commonly found in the femoral arteries (54%), followed by coronary calcification (38%), and carotid plaques (34%).

The association between atherosclerosis and risk factors was stronger in the femoral arteries than in the carotid or coronary arteries. When considering risk factors and the presence of carotid plaques, the area under the receiver-operating characteristic curve for predictive CACS increased from 0.665 to 0.689. The area increased to 0.719 when both femoral and carotid plaques were added (P<.001). The femoral odds ratio was 2.58, which exceeded the carotid odds ratio of 1.80 for prediction of positive CACS.

Up to 57% of participants had subclinical atherosclerosis who were considered to be low risk when applying risk scales based on traditional risk factors. This result suggests an association with early atherosclerosis with characteristics that are not currently considered on standard risk scales, which should be investigated in future studies.

“Follow-up data from AWHS and from other similar cohorts will definitely clarify the clinical relevance and the predictive value of early detection of asymptomatic atherosclerosis in otherwise low-risk patients,” the authors concluded. “Screening for femoral plaques, rather than carotid plaques, may be an appealing strategy for improving cardiovascular risk scales and predicting coronary disease.”

Reference

Laclaustra M, Casanovas J, Fernandez-Ortiz A, et al. Femoral and carotid subclinical atherosclerosis association with risk factors and coronary calcium: the AWHS study. J Am Coll Cardiol. 2016;67(11):1263-1274. doi: 10.1016/j.jacc.2015.12.056.