A combination of hydrogen bonding and chemical covalent crosslinking to fabricate a novel swim-bladder-derived dry heart valve material yields advantageous mechanical and biological properties

The current biological valve products used in transcatheter aortic valve replacement (TAVR) are mainly made of glutaraldehyde (GLUT)-crosslinked porcine and bovine pericardia, which need to be transported and stored in GLUT solution. This leads to prolonged preparation time and the presence of GLUT residue. Therefore, there has been interest in developing TAVR valves using a pre-crimped valve (also known as a dry valve). Herein, a natural, inexpensive, and widely available swim bladder was selected as the source of a biological valve functioning as a dry valve and was obtained via acellular processes and crosslinking fixation. With the help of multiple hydrogen bonds between polyphenols (represented by procyanidin and curcumin) and tissue, as well as the chemical crosslinking of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) with tissue, we found that this novel combined crosslinking method was able to successfully crosslink with an acellular swim bladder. The stabilities, mechanical properties, resistance to pre-folding/pre-compressing, flattening capability in water, hemocompatibility, cytocompatibility, and anti-calcification capability were systematically measured via a series of experiments. We demonstrated that this dry valve resulting from a combination of EDC/polyphenols exhibited superior properties compared with those of a control pericardial-based valve.