Thrombus refers to a blood clot. It forms when there is damage to the blood vessel. Platelets stick to the damaged vessel, attracted by the exposed collagen. The platelets form a platelet plug and stop the external bleeding. Chemicals released from the site attract clotting factors (see Clotting Cascade) which lead to fibrin formation. The fibrin sticks together and seals the wound forming the blood clot.
Sometimes the thrombus can break off the inner endothelium and move down the blood vessel. Occasionally, it can move down the pulmonary artery and get stuck, blocking the blood vessel. This prevents oxygenated blood to reach the heart cells. therefore the heart cells can no longer respire causing them to die. This can lead to a myocardial infarction.
A thrombus can be formed by the rupturing of an atheroma which is a fibrous plaque in blood vessels, the fibrous coating ruptures and the lipid centre enters the blood vessel. This lipid mixture contains thromboplastin which can cause clotting of the blood and form a thrombus.
- ↑ http://www.nlm.nih.gov/medlineplus/ency/imagepages/19462.htm
- ↑ This is from the Lancet report from the website https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1923523/
- ↑ Damjanov I. Pathology Secrets Chapter 7. 3rd edition. Philadelphia: Mosby Elsevier. 2009