Quantifying Atherosclerotic Burden with Ultrasound

Left and right common (CCA), internal and external carotid arteries and common femoral (CFA) arteries were examined (B-Mode and Doppler ultrasound, 7–13 MHz, linear transducer, M-Turbo, SonoSite Inc., Bothell, WA, USA) [26 ]. Transverse and longitudinal arterial views were obtained to assess the presence of atherosclerotic plaques. Near and far walls were analyzed, and images were obtained from anterior, lateral, and posterior angles. An atherosclerotic plaque was defined as focal wall thickening at least 50% greater than adjacent sectors, focal thickening that protrudes into the lumen at least 0.5 mm or intima-media thickness (IMT) ≥1.5 mm [26 ]. Plaque thickness was quantified at the site of maximal luminal infiltration, as the distance (perpendicular to the vessel wall) between the media-adventitia interface and the luminal surface of the plaque (automated procedures and digital calipers). Atherosclerotic burden was defined taking into account the number of plaques detected and territories compromised [1 (link)]. Additionally, atherosclerotic burden was defined considering dichotomous variables: 1 vs. ˃1 atherosclerotic plaques or territories with atherosclerotic plaques (carotid or femoral vs. carotid and femoral).