Thrombogenicity

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IUPAC definition
Property of a material (or substance) that induces and/or promotes
the formation of a thrombus. [1]

Thrombogenicity refers to the tendency of a material in contact with the blood to produce a thrombus, or clot. It not only refers to fixed thrombi but also to emboli, thrombi which have become detached and travel through the bloodstream. Thrombogenicity can also encompass events such as the activation of immune pathways and the complement system. All materials are considered to be thrombogenic[ citation needed ] with the exception of the normal state of endothelial cells which line blood vessels. [2] Certain medical implants appear non-thrombogenic due to high flow rates of blood past the implant, but in reality all are thrombogenic to a degree. Various surface treatments are available to minimize these thrombogenic effects.

Thrombus blood clot

A thrombus, colloquially called a blood clot, is the final product of the blood coagulation step in hemostasis. There are two components to a thrombus: aggregated platelets and red blood cells that form a plug, and a mesh of cross-linked fibrin protein. The substance making up a thrombus is sometimes called cruor. A thrombus is a healthy response to injury intended to prevent bleeding, but can be harmful in thrombosis, when clots obstruct blood flow through healthy blood vessels.

Complement system part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promotes inflammation, and attacks the pathogens cell membrane

The complement system is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promotes inflammation, and attacks the pathogen's cell membrane. It is part of the innate immune system, which is not adaptable and does not change over the course of an individual's lifetime. The complement system can, however, be recruited and brought into action by antibodies generated by the adaptive immune system.

Contents

A thrombogenic implant will eventually be covered by a fibrous capsule, the thickness of this capsule can be considered one measure of thrombogenicity, and if extreme can lead to the failure of the implant.

See also

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Biomaterial

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References

  1. "Terminology for biorelated polymers and applications (IUPAC Recommendations 2012)" (PDF). Pure and Applied Chemistry . 84 (2): 377–410. 2012. doi:10.1351/PAC-REC-10-12-04.
  2. López JA, Chen J (2009). "Pathophysiology of venous thrombosis". Thromb Res. 123 (Suppl 4): S30–4. doi:10.1016/S0049-3848(09)70140-9. PMID   19303501.

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