Imagine feeling a sudden shortness of breath, along with a pressure on your chest as if you felt your chest being squeezed, being compressed of air. Slowly tightening–unable to catch a breath, followed by a feeling of inexplicable fullness in your stomach, and a numbness in your left arm. Left with panic, you wonder, what could this be?
These are the symptoms of a myocardial infarction, commonly known as a heart attack, which is the heart’s response to the blockage of the arteries, and constriction of blood flow through the heart chambers. When a myocardial infarction occurs, the myocardium, the thickest layer of the heart muscle, is weakened, and unable to properly contract and expand, needed for the blood to flow throughout your body. According to the American Heart Association (2024), people from ages 40-75 most commonly suffer from myocardial infarctions, and their risks are higher if they suffer from high blood pressure, high cholesterol, are obese, etc.
Although there are ways to prevent and even treat a myocardial infarction, there are no cures set in place. These treatments do not have a long-term effect on the damage done, such as the stiff scarred tissue that causes the cardiovascular muscles to have difficulty in pumping blood through the heart. In these cases, a replacement for the tissue would be the most helpful. This is where tissue engineering comes into play.
Tissue engineering is an emerging field, where stem cells are manipulated into the type of cell that you need. If cells were characters in a video game, you could imagine stem cells as your level 1 character, which you can guide into several different paths to become a boxer (cartilage cells), a soccer player (skin cells), or even a basketball player (cardiovascular cells). The outcome of your character would depend on external factors, much like stem cells would depend on their environment to change into the cells that researchers want them to grow into.
One of the most important, if not the most important, characteristics of stem cells for cardiac regeneration is their origin from embryonic cells. This is because embryonic cells respond better to environmental changes since they do not have “memory” of being a different cell before. Embryonic cells are difficult to obtain, so stem cells from adult cells, specifically connective tissue, is another, and more easily obtained, option. Exploration in obtaining stem cells from connective tissue has been quite significant in the field, especially because there have been a few successes with creating different types of cells from these tissues. An advantage of using adult stem cells versus embryonic stem cells is the autoimmune response of the body to these cells. Adult stem cells are less likely to be rejected by the body.
Because tissue engineering is an emerging field, there are still some questions left to be answered. So far, a complete understanding of how the heart’s complexities are formed is yet to be determined, which slows down the process for a complete replacement of at least an artery or some muscular tissue in the heart. Currently, there are only mechanical or bioprosthetic valves as placeholders for tissue regeneration with stem cells, but they all have their limitations. There is only so much researchers can do with the available information; more people need to investigate the field of tissue engineering so that myocardial tissue regeneration can be obtained sooner rather than later.
References
Cordoves, E. M., Vunjak-Novakovic, G., & Kalfa, D. M. (2023). Designing biocompatible tissue engineered heart valves in situ. Journal of the American College of Cardiology, 81(10), 994–1003. https://doi.org/10.1016/j.jacc.2022.12.022
Radisic, M., Park, H., Gerecht, S., Cannizzaro, C., Langer, R., & Vunjak-Novakovic, G. (2007). Biomimetic approach to cardiac tissue engineering. Philosophical Transactions of the Royal Society B: Biological Sciences, 362(1484), 1357–1368. https://doi.org/10.1098/rstb.2007.2121
Understand your risks to prevent a heart attack. www.heart.org. (2024, January 9). https://www.heart.org/en/health-topics/heart-attack/understand-your-risks-to-prevent-a-heart-attack
Vunjak-Novakovic, G., Tandon, N., Godier, A., Maidhof, R., Marsano, A., Martens, T. P., & Radisic, M. (2010). Challenges in cardiac tissue engineering. Tissue Engineering Part B: Reviews, 16(2), 169–187. https://doi.org/10.1089/ten.teb.2009.0352