Michael Scharfschwerdt1, Moritz Leonhard1, Judith Lehmann1, Doreen Richardt1, Helmut Goldmann1, Hans-Hinrich Sievers2. 1. Department of Cardiac Surgery, University Clinic of Schleswig-Holstein, Lübeck, Germany. 2. Department of Cardiac Surgery, University Clinic of Schleswig-Holstein, Lübeck, Germany Department of Cardiac and Thoracic Vascular Surgery, University of Lübeck, Lübeck, Germany hans-hinrich.sievers@uksh.de.
Abstract
OBJECTIVES: Prosthetic replacement of the thoracic aorta with common Dacron prostheses impairs the aortic 'windkessel' and, in valve-sparing procedures, also aortic valve function. Elastic graft material may overcome these deficiencies. METHODS: Fresh porcine aortas including the root were set up in a mock circulation before and after replacement of the ascending part with a novel vascular prosthesis providing elastic behaviours. In a first series (n = 14), haemodynamics and leaflet motions of the aortic valve were investigated and also cyclic changes of aortic dimensions at different levels of the root. In a second series (n = 7), intravascular pressure and dimensions of the proximal descending aorta were measured and the corresponding wall tension was calculated. RESULTS: Haemodynamics of the aortic valve remain comparable after replacement. Though the novel prosthesis does not feature such high distensibility as the native aorta, the dynamic of the root was significantly increased compared with common Dacron prostheses at the commissural level, preserving 'windkessel' function. Thus, wall tension of the residual aorta remained unchanged; nevertheless, maximum pressure-time differential dp/dt increased by 13%. CONCLUSIONS: The use of the novel elastic prosthesis for replacement of the ascending aorta seems to be beneficial, especially with regard to the preservation of the aortic windkessel. Further studies will be needed to clarify long-term utilization of the material in vivo.
OBJECTIVES: Prosthetic replacement of the thoracic aorta with common Dacron prostheses impairs the aortic 'windkessel' and, in valve-sparing procedures, also aortic valve function. Elastic graft material may overcome these deficiencies. METHODS: Fresh porcine aortas including the root were set up in a mock circulation before and after replacement of the ascending part with a novel vascular prosthesis providing elastic behaviours. In a first series (n = 14), haemodynamics and leaflet motions of the aortic valve were investigated and also cyclic changes of aortic dimensions at different levels of the root. In a second series (n = 7), intravascular pressure and dimensions of the proximal descending aorta were measured and the corresponding wall tension was calculated. RESULTS: Haemodynamics of the aortic valve remain comparable after replacement. Though the novel prosthesis does not feature such high distensibility as the native aorta, the dynamic of the root was significantly increased compared with common Dacron prostheses at the commissural level, preserving 'windkessel' function. Thus, wall tension of the residual aorta remained unchanged; nevertheless, maximum pressure-time differential dp/dt increased by 13%. CONCLUSIONS: The use of the novel elastic prosthesis for replacement of the ascending aorta seems to be beneficial, especially with regard to the preservation of the aortic windkessel. Further studies will be needed to clarify long-term utilization of the material in vivo.
Authors: Maria C Palumbo; Alberto Redaelli; Matthew Wingo; Katherine A Tak; Jeremy R Leonard; Jiwon Kim; Lisa Q Rong; Christine Park; Hannah W Mitlak; Richard B Devereux; Mary J Roman; Arindam RoyChoudury; Christopher Lau; Mario F L Gaudino; Leonard N Girardi; Jonathan W Weinsaft Journal: Eur J Cardiothorac Surg Date: 2022-03-24 Impact factor: 4.191
Authors: Emilio O Bachtiar; Ozan Erol; Michal Millrod; Runhan Tao; David H Gracias; Lewis H Romer; Sung Hoon Kang Journal: J Mech Behav Biomed Mater Date: 2020-01-23