Changes in the Mechanical Properties of Chemically Treated Bovine Pericardium After a Short Uniaxial Cyclic Test

Abstract

The mechanical behavior of calf pericardium, a biomaterial utilized in the manufacture of cardiac bioprostheses, in response to a short tensile cyclic test has been evaluated. The trial involved 120 samples cut longitudinally or transversely, subjected to 10 cycles until a stress of between 1 and 3 MPa was reached. Tests of hardness and tear propagation were performed, and the results were compared with a control series. The energy loss was also computed, and it was approximately 10-fold greater in the first cycle than the loss in the subsequent nine cycles. Despite this singularity, they correlated very precisely. The effect of the direction in which the tissue is cut on energy loss was not significant nor the difference between hardness prior to and after testing. The results of the tear propagation tests gave no statistical differences prior to and after testing. From the obtained results, it seems that the test carried out does not affect significantly the mechanical properties of calf pericardium.

Mechanical Testing of Vascular Grafts

“…For thin plastic sheets, the tear propagation strength is a common criterion (ASTM Standard D1938-02 2002, which represents how a crack in the material affects its tearing strength. For tissue material, only few work is published according to such measurements (Purslow 1983;Koop and Lewis 2003;Claramunt et al 2013) and also no regulations to this are given in the standards for vascular grafts. However, in highly extensible materials the deformation energy of the specimen is significantly greater than the tearing energy (ASTM Standard D1938-02 2002, which underlines the importance of such measurement.…”

Simultaneous intraluminal imaging of tissue autofluorescence and eGFP-labeled cells in engineered vascular grafts inside a bioreactor

“…Conventional methods such as histology or mechanical tests to assess tissue properties as they grow, share a major shortcoming: they all require tissues to be moved out of the bioreactor and processed irreversibly [8,9], resulting in sample destruction, making the study costly and time-consuming. Therefore, there is an unmet need for non-destructive alternative methods to quantify tissue growth parameters in situ.…”