Myocardial scarring
Myocardial scarring is the accumulation of
Causes
Myocardial infarction
A
Coronary heart disease
Birth defect repairs
Another form of myocardial scarring results from surgical repairs.[2] Surgical repairs are often necessary for a person born with a congenital defect of the heart.[8] While surgical laparoscopy still leaves myocardial scarring, the trauma seems to be less damaging then naturally occurring scarring.[2]
Formation
Immediately after damage to the myocardium occurs, the damaged tissue becomes inflamed. Inflammation is the accumulations of neutrophils, macrophages, and lymphocytes at the site of the trauma.[9][10] In addition, "inflammatory cells upregulate the release of a myriad of signaling cytokines, growth factors, and hormones including transforming growth factor β, interleukins 1, 2, 6, and 10, tumor necrosis factor α, interferon γ, chemokines of the CC and CXC families, angiotensin II, norepinephrine, endothelin, natriuretic peptides, and platelet-derived growth factors".[10] Both the necrotic cells and the inflamed myocardium secrete and activate matrix metalloproteinase. Metalloproteinase aids in the destruction and reabsorption of necrotic tissue. After several days, collagen accumulation at the site of injury begins to occur.[10] As part of the extracellular matrix, granulated tissue consisting of fibrin, fibronectin, laminin, and glycosaminoglycan is suspended in a collagen base.[10] The extracellular matrix acts as scaffolding for the fibrillar collagen to form. The fibrillar collagen is the main constitute of what will become the scar tissue.[10]
References
- ^ PMID 21220243.
- ^ PMID 19897714.
- ^ "FIBROMA". Merriam-Webster. Retrieved 2020-03-23.
- PMID 25347856.
- ^ a b "ISCHEMIA". Merriam-Webster. Retrieved 2020-03-23.
- ^ S2CID 203626142.
- ^ "CORONARY HEART DISEASE". Merriam-Webster. Retrieved 2020-03-23.
- ^ CDC (2019-11-22). "What are Congenital Heart Defects? | CDC". Centers for Disease Control and Prevention. Retrieved 2020-03-23.
- S2CID 2118209.
- ^ PMID 26426470.