Contribution of computational model for assessment of heart tissue local stress caused by suture in LVAD implantation

Abstract

Our computational model showed a reliable ability to provide and predict various local tissue stresses created by suture penetration into the myocardium. In addition, this model contributed to providing valuable information useful to design less traumatic sutures for LVAD implantation. Therefore, our computational model is a promising tool to predict and optimize LVAD myocardial suture.

Microstructural deformation observed by Mueller polarimetry during traction assay on myocardium samples

“…However, this manual measure has already been used in the literature to identify the tissue main orientation 26,28 . found in the literature [22][23][24] : after observing first a non-linear region, the curve becomes linear (see Fig. 3).…”

“…Our focus is set on the latter. Various mechanical assays have been performed, such as uniaxial traction [21][22][23][24] , biaxial ones [25][26][27] or shear experiments 26,28 with the ultimate aim to determine the anisotropic mechanical response of the tissue. The anisotropy arises mainly from the cardiomyocyte orientation, but some experiments point towards a role of the cardiomyocyte bundles in the response 26,28 .…”

FRESH 3D Bioprinting a Full-Size Model of the Human Heart

“…We found the suture retention strength of these printed alginate blocks to be 0.17 ± 0.03 N (mean ± SD, n = 5) and a representative extension-load graph of the suture pulling test on a FRESH-printed alginate block (Figure G). Although compressive modulus data falls in the range of cardiac tissue, our 3D bioprinted alginate constructs exhibit a low suture retention strength, below that of native pericardium and myocardium, which have been reported to be around 2.84 and 15.43 N, respectively. , Although the printed alginate had a low compliance when pulled on by a suture, strategies exist to increase elastic modulus and strength, including changing the cation type used for alginate crosslinking, and changing the G/M ratio of alginate monomers …”

“…Although compressive modulus data falls in the range of cardiac tissue, our 3D bioprinted alginate constructs exhibit a low suture retention strength, below that of native pericardium and myocardium, which have been reported to be around 2.84 and 15.43 N, respectively. 24,25 Although the printed alginate had a low compliance when pulled on by a suture, strategies exist to increase elastic modulus and strength, including changing the cation type used for alginate crosslinking, and changing the G/M ratio of alginate monomers. 26 FRESH 3D Printing a Section of Patent Coronary Artery.…”