Véralvadás

Véralvadás, also known as blood coagulation, is a vital physiological process that prevents excessive bleeding when a blood vessel is injured. It involves a complex cascade of biochemical reactions where a series of blood proteins, called clotting factors, are activated in sequence. This cascade culminates in the formation of a fibrin clot, which seals the damaged vessel and stops the flow of blood.

The process begins immediately after an injury. Platelets, small blood cells, aggregate at the site of the wound and form a temporary plug. Simultaneously, the coagulation cascade is initiated. This cascade involves both an intrinsic and an extrinsic pathway, which converge at a common pathway. The ultimate goal is the conversion of fibrinogen, a soluble protein in the blood, into fibrin, an insoluble protein that forms a mesh-like structure. This fibrin mesh traps blood cells and platelets, creating a stable clot.

Once the bleeding has stopped and the wound begins to heal, the body activates a process called fibrinolysis. Fibrinolysis breaks down the fibrin clot, restoring normal blood flow. Disorders of véralvadás can lead to either excessive bleeding (hemorrhage) or the formation of unwanted blood clots within vessels (thrombosis), which can cause serious health problems like stroke or heart attack. These disorders can be inherited, such as hemophilia, or acquired due to various medical conditions or medications. Understanding véralvadás is crucial for diagnosing and managing bleeding and clotting disorders.