Brian Mere
BMED 213-70
HW # 3

Vavular Heart Disease (VHD) is a disease that denotes the malfunction of a heart valve within a human. Normally, this issue doesn't occur in adult humans since babies that have the condition usually aren't able to survive for very long after developing the condition [1]. As a result, usually methods to replace the heart tissue as it degrades is used. One more obvious method that's used is to use heart patches, or "tissue patch constructs" [2]. These are made typically of "synthetic polymers and natural biological materials" that help bind to the hole in the heart [2]. Essentially, they are band-aids on the heart, but the large problem is making sure that both the immune system doesn't try to attack and destroy it, but that it also structurally sound for normal valvular operations.

2. Describe the basic components and functions of the tissue/organ that the medical device needs to replace or enhance.

Two aspects are primarily needed to be replicated by the TPC (tissue patch construct). For one, it needs to "facilitate in vivo biochemical signaling", helping it communicate and cooperate with the rest of the heart [2]. The other aspect is to "recapitulate the extracellular matrix (ECM) microenvironment", which is within the cells [2].

3. Describe the type(s) of biomaterial(s) that are used in the medical device to treat the condition selected in question 1. Describe two properties of a biomaterial that enable that biomaterial to meet the needs of the medical device.

Synthetic polymers are usually used for this purpose. Mainly, they can better work with the biological environment they are placed in because they can have added or removed concentrations of various chemicals. For instance, materials like "PCL, PGS, PLGA, PU, PLLA, ..." are each considered for this function because of their structural form [2]. However, they fail to help with the function of the ECM, which the next technological advancement helps out with [2].

4. Describe one recent technological advancement in the type of medical device that you have selected.

A PCL gelatin patch recently made helps reflect the traditional structure of the heart tissue [3]. Mainly, it "promotes repair of the infracted [sic] myocardium and improves cardiac functions by enhancing the survival of the transplanted cells" [3]. In layman's terms, the main pillar of being technically biocompatible is made here, because the immune system starts to work with the new heart tissue in order to facilitate healing of the opening in the heart.

References

[1] B. Taghizadeh et al., “Biomaterials in valvular heart diseases,” Frontiers in Bioengineering and Biotechnology, vol. 8, Dec. 2020. doi:10.3389/fbioe.2020.529244

[2] S. Vasu, J. Zhou, J. Chen, P. V. Johnston, and D.-H. Kim, “Biomaterials-based approaches for cardiac regeneration,” Korean Circulation Journal, vol. 51, no. 12, p. 943, 2021. doi:10.4070/kcj.2021.0291

[3] Q. Wang et al., “Mesenchymal stem cell‐loaded cardiac patch promotes epicardial activation and repair of the infarcted myocardium,” Journal of Cellular and Molecular Medicine, vol. 21, no. 9, pp. 1751–1766, Feb. 2017. doi:10.1111/jcmm.13097