After complex endovascular aortic repair (cEVAR), long-term surveillance is advocated to monitor for potential (stent-related) complications. Although various imaging modalities are used, computed tomography angiography remains the standard in current clinical practice worldwide. However, radiopaque markers can cause metal artifacts and scattering, hampering assessment of patency of side branches. The maximal systolic acceleration (ACCmax) is a relatively new duplex ultrasound (DUS) parameter measured distal to a stenosis, avoiding in-stent assessment and scattering. The aim of this article is to illustrate the potential diagnostic utility of the ACCmax after cEVAR and visceral artery stenting in general. The ACCmax is measured at the maximal slope of the upstroke during the systolic phase in arterial flow. By manually connecting 2 points, a tangent line is created in which the maximal acceleration is automatically calculated and expressed in m/s2. A higher value reflects better arterial perfusion proximal to its measurement point. One measurement of a visceral artery takes about 5 minutes. ACCmax measurements can be a useful addition during DUS follow-up after cEVAR or visceral artery stenting, possibly decreasing radiation exposure, nephrotoxicity, and health care costs. Long-term surveillance after complex endovascular aortic repair (cEVAR) is necessary to monitor for potential (stent-related) complications. Although CTA is the most common modality for imaging, metal artifacts and scattering can hamper the assessment of stent patency. The maximal systolic acceleration (ACCmax) is a duplex ultrasound based parameter that reflects arterial perfusion proximal to its measurement point. Due to its noninvasive nature, it can be a useful addition during follow-up after cEVAR or visceral artery stenting, possibly decreasing radiation exposure, nephrotoxicity and health care costs as well.
Read full abstract