ABC | Volume 112, Nº6, June 2019

Statement Vascular Ultrasound Statement from the Department of Cardiovascular Imaging of the Brazilian Society of Cardiology – 2019 Arq Bras Cardiol. 2019; 112(6):809-849 Table 1 – When to measure the intima-media thickness 1. Intermediate cardiovascular risk: use the IMT measurement as an aggravating factor for high risk reclassification 10 2. Patients known to have a higher cardiovascular risk and hard clinical classification: • Patients with familial hypercholesterolemia 11 • Patients with autoimmune diseases or who use immunosuppressants, corticosteroids, antiretroviral drugs, or other medicines that induce elevation of cholesterol 12 • History of early cardiovascular disease in first-degree relatives 10 • Individuals < 60 years with a severe abnormality in a risk factor 10 • Women < 60 years with at least two risk factors 10 IMT: intima-media thickness. Table 2 – Protocol to measure intima-media thickness • Two-dimensional fundamental imaging • Do not zoom • Transducer with frequency > 7 MHz • Proper gain adjustment; depth between 3.0 and 4.0 cm • Longitudinal plane of the common carotid and carotid bifurcation • Capture images in the anterior and posterior accesses or the sternocleidomastoid muscle, with the most rectilinear image possible and with a well-defined double-line pattern, and choose the best one • Measure it in the posterior wall of the common carotids on the right and left sides, 1 cm from the bifurcation, in automatic/semi-automatic mode above or below the 75 percentile and the table used, with its bibliographic reference. Inform the presence of carotid plaques, with their specific characteristics and quantification, according to the criteria recommended by the recent Brazilian consensus. 1 2.3. Morphological Evaluation of Carotid Atherosclerotic Plaques CP morphology plays an essential role in the incidence of cerebrovascular events and can also be an important predictor of events. 17,18 Recognizing the ultrasound characteristics of the plaque can help to identify unstable ones. Describe the following properties: location, extension, echogenicity, texture, surface, presence of movable components, and anechoic areas next to the fibrotic capsule. Report these characteristics for the most important plaques, particularly those with more than 50% stenosis. • Location: we recommend subdividing the carotids into distal and proximal common carotid, bifurcation, external branch, and proximal and medial internal branch (Figure 2). • Extension : must be measured, as it can be correlated with events and affects the choice of surgical and endovascular treatment. 19 • Echogenicity : defined by comparing the plaque echogenicity to that of adjacent structures (blood, muscle, adventitia of the vessel, and bone), and classified into: 20 - Hypoechoic or echolucent: darker, that is, echogenicity similar to that of blood and less echogenic than the sternocleidomastoid muscle. - Isoechoic: echogenicity close to that of muscle. - Hyperechoic: lighter than the adjacent muscle. - Calcified: very echogenic, creating acoustic shadowing due to calcium deposition. Echogenicity is comparable to that of the bone. • Echotexture : Reilly et al. 21 classified the texture of the plaque as homogeneous or heterogeneous. - Homogeneous: uniform in both low and high echo levels. - Heterogeneous: a mixture of high, medium, and low echo levels. • Surface : lumen surface is categorized into three classes: 20,22 - Smooth: irregularities of less than 0.4 mm depth. - Irregular: from 0.4 to 2 mm depth. - Ulcerated: crater greater than 2.0 mm depth. 2.4. Quantification of Carotid Artery Stenosis Several institutions published evaluation criteria for carotid stenosis, with some differences in interpretation. 3,23-25 However, in 2003, a consensus document was published in the USA to make recommendations on the performance of VUS of carotid arteries. The United Kingdom followed them in 2009, and the DCI of the Brazilian Society of Cardiology (BSC) in 2015. 1,3,4 814