Véralvadék

Véralvadék, also known as a blood clot, is a semi-solid mass of blood that forms when blood changes from a liquid to a gel. This process, called coagulation or clotting, is a vital physiological mechanism that prevents excessive bleeding when a blood vessel is injured. Platelets, a type of blood cell, aggregate at the site of injury and form a temporary plug. Simultaneously, a complex cascade of proteins, known as clotting factors, are activated. This cascade culminates in the conversion of fibrinogen, a soluble protein, into fibrin, an insoluble protein that forms a mesh. This fibrin mesh traps blood cells and platelets, reinforcing the platelet plug and creating a stable clot.

Once the injured blood vessel has healed, the body typically initiates a process called fibrinolysis to break down and remove the clot. However, blood clots can also form inappropriately within blood vessels, even in the absence of injury. This can occur due to various factors such as slow blood flow, damage to the vessel wall, or an increased tendency for blood to clot, known as hypercoagulability. When such clots form, they can obstruct blood flow, leading to serious medical conditions like deep vein thrombosis (DVT), pulmonary embolism (PE), stroke, or heart attack. The formation and dissolution of véralvadék are tightly regulated processes, and disruptions to this balance can have significant health consequences.