Evaluation of transcatheter heart valve biomaterials: Biomechanical characterization of bovine and porcine pericardium. (November 2017)

• Record Type: Journal Article
• Authors: Caballero, Andrés; Sulejmani, Fatiesa; Martin, Caitlin; Pham, Thuy; Sun, Wei
• Is Part Of: Journal of the mechanical behavior of biomedical materials. Volume 75(2017)
• Page Start: 486
• Page End: 494
• Publication Date: 2017-11
• Subjects: Bovine pericardium -- Porcine pericardium -- Aging -- Biaxial testing -- Uniaxial testing -- Collagen -- Transcatheter aortic valve; Biomedical materials -- Periodicals; Biomedical materials -- Mechanical properties -- Periodicals; Biomedical materials; Biomedical materials -- Mechanical properties; Periodicals; Electronic journals; 610.28
• DOI: 10.1016/j.jmbbm.2017.08.013
• Languages: English
• ISSNs: 1751-6161

Abstract

Abstract: Objective: Bovine pericardium (BP) has been identified as a choice biomaterial for the development of surgical bioprosthetic heart valves (BHV) and transcatheter aortic valves (TAV). Porcine pericardium (PP) and younger BP have been suggested as candidates TAV leaflet biomaterials for smaller-profile devices due to their reduced thickness; however, their mechanical and structural properties remain to be fully characterized. This study characterized the material properties of chemically treated thick (PPK) and thin (PPN) PP, as well as fetal (FBP), calf (CBP) and adult (ABP) BP tissues in order to better understand their mechanical behavior. Methods: Planar biaxial testing and uniaxial failure testing methods were employed to quantify tissue mechanical responses and failure properties. Fiber characteristics were examined using histological analysis. Results: ABP and CBP tissues were significantly stiffer and stronger than the younger FBP tissues. Histological analysis revealed a significantly larger concentration of thin immature collagen fibers in the FBP tissues than in the ABP and CBP tissues. While PP tissues were thinnest, they were stiffer and less extensible than the BP tissues. Conclusions: Due to comparable mechanical properties but significantly reduced thickness, CBP tissue may be a more suitable material for TAV manufacturing than ABP tissue. FBP tissue, despite its reduced thickness and higher flexibility, was weaker and should be studied in more detail. Although PP tissues are the thinnest, they were least extensible and failed at earlier strain than BP tissues. The differences between PP and BP tissues should be further investigated and suggest that they should not be used interchangeably in the manufacturing of TAV. Graphical abstract: fx1 Highlights: Complete set of biaxial and uniaxial data for bovine-BP and porcine-PP pericardium. Calf BP has a similar mechanical response than Adult BP but is thinner. Fetal BP is thinner and more extensible than older BP but weaker. While PP is thinnest, it is stiffer and less extensible than BP.