ECG-Synchronized Computed Tomography in Assessing the Elastic Properties of the Ascending Aorta: Clinical and Experimental Study

<b>Background</b>: Recent studies have demonstrated the feasibility and potential of using ECG-synchronized computed tomography (CT) to assess the elastic and deformation properties of the aorta. However, to date, there is insufficient evidence to support the practical use of this approach. We aimed to study the association of CT-derived indices, characterizing ascending aorta elasticity, with the biomechanical properties of intraoperative ascending aorta (AsAo) samples, and to assess its predictive potential in non-surgical patients with ascending aorta dilatation. <b>Methods</b>: In total, 71 patients with AsAo dilatation (>45 mm) and 29 control patients (AsAo diameter < 40 mm) underwent ECG-synchronized CT-aortography. In 42 surgical patients, CT-derived parameters (circumferential strain, compliance, stiffness) were compared with the tensile strength and relative strain of intraoperative aortic samples. In 29 non-surgical patients (diameter 45-50 mm), the predictive potential of CT-derived elasticity indices was determined over 36 months of follow-up. <b>Results</b>: A moderate correlation was found between CT-derived strain/distensibility and ex vivo relative strain. CT data confirmed that dilated aortas are stiffer and less elastic than those in controls. In 29 non-surgical patients, CT elasticity parameters did not demonstrate the ability to predict adverse aneurysm progression. <b>Conclusions</b>: While CT can assess aortic elasticity correlated with ex vivo aortic properties, these parameters lacked prognostic value for the growth in small aneurysms.