Bioengineering Strategies for Polymeric Scaffold for Tissue Engineering an Aortic Heart Valve: An Update

Abstract

The occurrence of dysfunctional aortic valves is increasing every year, and current replacement heart valves, although having been shown to be clinically successful, are only short-term solutions and suffer from many agonizing long-term drawbacks. The tissue engineering of heart valves is recognized as one of the most promising answers for aortic valve disease therapy, but overcoming current shortcomings will require multidisciplinary efforts. The use of a polymeric scaffold to guide the growth of the tissue is the most common approach to generate a new tissue for an aortic heart valve. However, optimizing the design of the scaffold, in terms of biocompatibility, surface morphology for cell attachments and the correct rate of degradation is critical in creating a viable tissue-engineered aortic heart valve. This paper highlights the bioengineering strategies that need to be followed to construct a polymeric scaffold of sufficient mechanical integrity, with superior surface morphologies, that is capable of mimicking the valve dynamics in vivo. The current challenges and future directions of research for creating tissue-engineered aortic heart valves are also discussed.

Application of Heparin/Collagen‐REDV Selective Active Interface on ePTFE Films to Enhance Endothelialization and Anticoagulation

“…Results of cell activity test on unmodified ePTFE, (HEP/COL)5 modified ePTFE, REDV-(HEP/COL)5 modified ePTFE, and REVD-(HEP/ COL)5 modified ePTFE(6,24, 48, and 72 h).…”

De-Endothelialized Aortic Homografts: A Promising Scaffold Material for Tissue-Engineered Heart Valves

“…In addition, the scaffold should be porous for ingrowth of seed cells [Lueders et al, 2014]. Nowadays, decellularized isogeneic aortic roots are frequently used as a scaffold for TEHV [Morsi, 2014]. Harsh decellularization can obviously weaken the antigenicity of an aortic homograft, but at the same time mechanical and structural characteristics are seriously impaired [Pennel et al, 2014].…”

“…The ideal scaffold material should possess suitable biomechanical characteristics as well as biocompatibility [Moreira et al, 2014]. Presently, acellular aortic root homografts are frequently used as a scaffold for TEHV and many researchers are focusing on strategies to remove all cellular constituents of aortic homografts [Morsi, 2014].…”

Polymeric Scaffolds for Bioartificial Cardiovascular Prostheses

“…The degradation rates, besides the specific molecular weight, are dependent on their crystallinity [70]. Thus, poly-4-hydroxybutyric acid degrades rather fast in vivo [71], whereas polyhydroxyoctanoate is still detectable after 24 weeks [72]. The mechanism of degradation is based on a hydrolytic splitting of ester bonds and distinguishes through a delayed loss of mass, as the loose chain fragments only start to diffuse at a certain length [16].…”