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 ___________________________ *This document will not cover the VUS assessment in the postoperative follow-up of aortoiliac obstructions, in case of suspected diagnosis of aortic dissection and arteritis. We suggest the recent publication of DCI recommendations as additional reading. 2 Table 11 – Classification of the degree of stenosis with pulsed wave Doppler Classification Systolic velocity ratio Stenosis < 50% V2/V1 < 2.0 Stenosis ≥ 50% V2/V1 ≥ 2.0 Stenosis ≥ 70% V2/V1 ≥ 4.0 Occlusion Lack of flow 3.2.2. Examination Protocol for Aortoiliac Atherosclerotic Disease According to DCI Recommendations (Table 10) 3.2.2.1. Diagnostic Criteria • Stenosis : measure PSV at the lesion site (V2) and 1 to 2 cm proximal to the lesion (V1) and calculate the velocity ratio (V2/V1). Determine the spectral curve with an angle ≤ 60 o parallel to the turbulent flow axis (Figure 9). The degree of stenosis should be classified according to table 11. • Occlusion : lack of flow in any aortoiliac segment, even with scan parameters that detect low-velocity flows. Presence of typical preocclusive waveform (high peripheral resistance, low peak systolic velocity, and lack of diastolic flow). Collateral vessels can be found in occluded pre- and post-segment (re-entry point). The post-occlusive spectrum is characterized by monophasic waveform, with reduced PSV and prolonged acceleration time - parvus/tardus (Figure 9). Hypoechoic image with a concave interface in colored flow and spectrum in preocclusive staccato pattern suggests thromboembolic occlusion. • Essential information to include in the medical report: - Diagnostic examination: ○ Report if there were technical difficulties during the examination. ○ In case of dilations, inform the largest diameter of the aorta and/or iliac arteries. Figure 9 – Color flow imaging showing the flow proximal to the lesion in red and the turbulent flow at the lesion site (arrow). The diagrams A and C demonstrate the velocity spectrum with Doppler. (A) Cursor proximal to the lesion to measure V1. (B) Cursor at the lesion site to measure V2. (C) Cursor distal to the lesion with damped waveform. VELOCITY VELOCITY VELOCITY SYSTOLE SYSTOLE SYSTOLE DIASTOLE DIASTOLE DIASTOLE TIME TIME TIME - Additional information for the preoperative examination: • Inform the presence, aspect, and location of atherosclerotic plaques, as well as the degree of stenosis of lesions. Table 12 lists the general limitations of VUS examination. 3.3. Mesenteric Arteries 3.3.1. General Considerations Mesenteric vessels are represented by the celiac trunk (CT) and superior and inferior mesenteric arteries (SMA and IMA, respectively). Anatomically, CT starts just below the aortic hiatus of the diaphragm and originates the splenic and hepatic arteries. SMA and IMA begin approximately 0.5 to 2 cm below CT and 4 to 5 cm above the aortic bifurcation, respectively (Figure 10). 35 824