J-M Bourget1, R Zegdi2, J Lin3, P Wawryko4, Y Merhi5, C Convelbo2, J Mao1, Y Fu3, T Xu1, N O Merkel1, L Wang3, L Germain1, Z Zhang1, R Guidoin6. 1. Department of Surgery, Faculty of Medicine, Vandry Building, Laval University, Axe médecine régénératrice, centre de recherche du CHU de Québec, Québec, Canada. 2. Inserm, U97O, université René-Descartes, service de chirurgie cardiovasculaire, hôpital européen Georges-Pompidou, 75015 Paris, France. 3. Key Laboratory of Textile Science and Technology of Ministry of Education and College of Textile, Donghua University, Shanghai, China. 4. Department of Pathology, University of Manitoba, Winnipeg, MB, Canada. 5. Laboratoire de thrombose et hémostase, centre de recherche, institut de cardiologie, université de Montréal, Montréal, QC, Canada. 6. Department of Surgery, Faculty of Medicine, Vandry Building, Laval University, Axe médecine régénératrice, centre de recherche du CHU de Québec, Québec, Canada. Electronic address: robert.guidoin@fmed.ulaval.ca.
Abstract
INTRODUCTION: Transcathether heart valve replacement has gained considerable acceptance during the last decades. It is now part of the armamentarium for aortic valve replacement. The procedure proved to be highly efficient. However the issues of the blood compatibility and tissue durability were not raised and the adverse events were probably under-reported, according to observations of thrombosis after deployment. MATERIAL AND METHOD: Bovine pericardium leaflets were sewn inside a 26mm diameter stainless steel stent to manufacture these valves (one control and two experimental). The correlation between the trauma and the acute thombogenicity of bovine pericardium leaflets, after crimping and ballooning, was investigated via an in vitro blood flow with labeled platelets. These leaflets were processed for histology: scanning electron microscopy, light microscopy, and transmission electron microscopy. RESULTS: The control specimens showed a regular pericardium structure with some blood cells deposited on the collagen fibrous surface (inflow) and scarce blood cells deposited on the serous surface (outflow). After crimping and ballooning, the structure of the pericardium was severely injured, eventually with delaminations and ruptures. The blood cell uptake was considerably increased compared to the control. CONCLUSION: It would therefore be appropriate to pay more attention to the design of the valves. Specifically, the incorporation of a buffer tissue or fabric between the pericardium and the metallic stent is suggested. The issue of ballooning deserves detailed and in depth investigation regarding the lifetime of the device.
INTRODUCTION: Transcathether heart valve replacement has gained considerable acceptance during the last decades. It is now part of the armamentarium for aortic valve replacement. The procedure proved to be highly efficient. However the issues of the blood compatibility and tissue durability were not raised and the adverse events were probably under-reported, according to observations of thrombosis after deployment. MATERIAL AND METHOD:Bovine pericardium leaflets were sewn inside a 26mm diameter stainless steel stent to manufacture these valves (one control and two experimental). The correlation between the trauma and the acute thombogenicity of bovine pericardium leaflets, after crimping and ballooning, was investigated via an in vitro blood flow with labeled platelets. These leaflets were processed for histology: scanning electron microscopy, light microscopy, and transmission electron microscopy. RESULTS: The control specimens showed a regular pericardium structure with some blood cells deposited on the collagen fibrous surface (inflow) and scarce blood cells deposited on the serous surface (outflow). After crimping and ballooning, the structure of the pericardium was severely injured, eventually with delaminations and ruptures. The blood cell uptake was considerably increased compared to the control. CONCLUSION: It would therefore be appropriate to pay more attention to the design of the valves. Specifically, the incorporation of a buffer tissue or fabric between the pericardium and the metallic stent is suggested. The issue of ballooning deserves detailed and in depth investigation regarding the lifetime of the device.
Authors: Alexander E Kostyunin; Arseniy E Yuzhalin; Maria A Rezvova; Evgeniy A Ovcharenko; Tatiana V Glushkova; Anton G Kutikhin Journal: J Am Heart Assoc Date: 2020-09-21 Impact factor: 5.501