Background - Detection of subclinical atherosclerosis improves risk prediction beyond cardiovascular risk factors (CVRFs) and risk scores, but quantification of plaque burden may improve it further. Novel 3-dimensional vascular ultrasound (3DVUS) provides accurate volumetric quantification of plaque burden.

Objectives- The authors evaluated associations between 3DVUS-based plaque burden and CVRFs and explored potential added value over simple plaque detection.

Methods - The authors included 3,860 (92.2%) PESA (Progression of Early Subclinical Atherosclerosis) study participants (age 45.8 ± 4.3 years; 63% men). Bilateral carotid and femoral territories were explored by 3DVUS to determine the number of plaques and territories affected, and to quantify global plaque burden defined as the sum of all plaque volumes. Linear regression and proportional odds models were used to evaluate associations of plaque burden with CVRFs and estimated 10-year cardiovascular risk.

Results - Plaque burden was higher in men (63.4 mm3 [interquartile range (IQR): 23.8 to 144.8 mm3] vs. 25.7 mm3 [IQR: 11.5 to 61.6 mm3] in women; p < 0.001), in the femoral territory (64 mm3[IQR: 27.6 to 140.5 mm3] vs. 23.1 mm3 [IQR: 9.9 to 48.7 mm3] in the carotid territory; p < 0.001), and with increasing age (p < 0.001). Age, sex, smoking, and dyslipidemia were more strongly associated with femoral than with carotid disease burden, whereas hypertension and diabetes showed no territorial differences. Plaque burden was directly associated with estimated cardiovascular risk independently of the number of plaques or territories affected (p < 0.01).