Cardiopulmonary-induced deformations of the thoracic aorta following thoracic endovascular aortic repair

Abstract

Objectives Thoracic endovascular aortic repair has become a preferred treatment strategy for thoracic aortic aneurysms and dissections. Yet, it is not well understood if the performance of endografts is affected by physiologic strain due to cyclic aortic motion during cardiac pulsation and respiration. We aim to quantify cardiac- and respiratory-induced changes of the postthoracic endovascular aortic repair thoracic aorta and endograft geometries. Methods Fifteen thoracic endovascular aortic repair patients (66 ± 10 years) underwent cardiac-resolved computed tomography angiographies during inspiratory/expiratory breath holds. The computed tomography angiography images were utilized to build models of the aorta, and lumen centerlines and cross-sections were extracted. Arclength and curvature were computed from the lumen centerline. Effective diameter was computed from cross-sections of the thoracic aorta. Deformation was computed from the mid-diastole to end-systole (cardiac deformation) and expiration to inspiration (respiratory deformation). Results Cardiac pulsation induced significant changes in arclength, mean curvature, maximum curvature change, and effective diameter of the ascending aorta, as well as effective diameter of the stented aortic segment. Respiration, however, induced significant change in mean curvature and effective diameter of the ascending aorta only. Cardiac-induced arclength change of the ascending aorta was significantly greater than respiratory-induced arclength change. Conclusions Deformations are present across the thoracic aorta due to cardiopulmonary influences after thoracic endovascular aortic repair. The geometric deformations are greatest in the ascending aorta and decline at the stented thoracic aorta. Additional investigation is warranted to correlate aortic deformation to endograft performance.

Multiaxial pulsatile dynamics of the thoracic aorta and impact of thoracic endovascular repair

“…For example, pre- and post-TEVAR deformations provide deformation damping (at the site of the endograft) and augmentation (at adjacent native sites) factors, which can be used for product development of devices placed initially, as well as those implanted subsequently. In addition, quantification of inner and outer surface curvatures, a unique feature of the methods presented in this study, provides additional geometric information that centerline-based methods cannot capture [ 18 , 19 ]. The presence of high inner surface curvatures at the proximal landing zone may increase the risk of endograft mal-apposition and Type 1a endoleak, thus surface curvatures may be useful for guiding implantation strategy [ [26] , [27] , [28] , [29] ].…”

“…1 depicts the overall procedure of aortic modeling and extraction of centerline, inner and outer surface curve, as well as cross-sectional geometry. For each cardiac frame pre- and post-TEVAR, CTA images were processed using custom vascular modeling software (SimVascular, Open Source Medical Software Corp., San Diego, CA) [ [17] , [18] , [19] ]. First, paths of the aorta and adjacent branches were constructed along the lumen shown in CT images.…”

Influence of thoracic endovascular aortic repair on true lumen helical morphology for Stanford type B dissections

“…Patients with chronic or acute Stanford type B dissection who had been treated with TEVAR were retrospectively included to this study. [9][10][11][12] All patients gave informed consent and the study was approved by the Institutional Review Board. This study performed visual screening of patients' computed tomography angiography (CTA) data, and included those with distinct separation of true and false lumen with dissection length exceeding 5 cm.…”