Hemodynamic consequences of TEVAR with in situ double fenestrations of left carotid artery and left subclavian artery. (February 2020)

• Record Type: Journal Article
• Authors: Qiao, Yonghui; Mao, Le; Ding, Ying; Fan, Jianren; Zhu, Ting; Luo, Kun
• Is Part Of: Medical engineering & physics. Volume 76(2020)
• Page Start: 32
• Page End: 39
• Publication Date: 2020-02
• Subjects: Aortic dissection -- Aneurysm -- Thoracic endovascular aortic repair -- Left carotid artery -- Left subclavian artery -- non-Newtonian -- Windkessel model -- Computational fluid dynamics; CFD computational fluid dynamics -- TEVAR thoracic endovascular aortic repair -- ISF in situ fenestration -- BT brachiocephalic trunk -- LCA left carotid artery -- LSA left subclavian artery -- WSS wall shear stress -- TAWSS time-averaged WSS -- OSI oscillatory shear index -- RRT relative residence time; Biomedical engineering -- Periodicals; Biomedical Engineering -- Periodicals; Physics -- Periodicals; Génie biomédical -- Périodiques; Biomedical engineering; Electronic journals; Periodicals; 610.28
• DOI: 10.1016/j.medengphy.2019.10.016
• Languages: English
• ISSNs: 1350-4533

Abstract

Highlights: CFD methodology is firstly used to analyze hemodynamics after ISF-TEVAR. There is a pressure difference between the inner and outer surfaces of the LSA stent. The aortic arch and rebuild LCA and LSA are prone to thrombosis. Double fenestrations have a great impact on hemodynamics. The aortic arch and rebuilt branches should be closely watched during follow-up. Abstract: The aortic major branches after thoracic endovascular aortic repair (TEVAR) could be preserved by in situ fenestration (ISF). This study aims to explore the hemodynamic consequences of ISF-TEVAR with double fenestrations. Two patients with aortic dissection and aneurysm, respectively, were treated by ISF-TEVAR and both the left carotid artery (LCA) and left subclavian artery (LSA) were reconstructed by fenestration technique. The blood was considered a non-Newtonian fluid and the Windkessel model was adopted at the aortic outlets. Simulations were performed in two postoperative models to analyze the effects of the double fenestration stents on the hemodynamics. The postoperative wall pressure of the LCA and LSA is relatively low and the pressure difference between the inner and outer walls of the protruding segment of the LSA stent is found. Acceleration occurs when blood flows around the fenestration stents and the shear-thinning rheological behavior is observed at the aortic arch. Moreover, regions susceptible to thrombosis are identified and the surface exposed to high relative residence time is located at the aortic arch after the LSA stent. The presence of the double fenestration stents has a profound impact on the postoperative hemodynamics, and the aortic arch and rebuilt branches should be closely watched during follow-up.