is the formation of a
Clot or
Thrombus inside a
Blood Vessel , obstructing the flow of
Blood through the
Circulatory System . '''Thromboembolism''' is a general term describing both thrombosis and its main complication which is
Embolisation .
Classically, thrombosis is caused by abnormalities in one or more of the following (
Virchow 's triad):
- The composition of the blood
- Quality of the vessel wall
- Nature of the blood flow
The formation of a thrombus is usually caused by an injury to the vessel's wall, either by trauma or infection, and by the slowing or stagnation of blood flow past the point of injury. High altitude has also been known to induce thrombosis
{Link without Title} . Occasionally, abnormalities in
Coagulation are to blame.
Intravascular
Coagulation follows, forming a structureless mass of
Red Blood Cell s,
Leukocyte s, and
Fibrin .
There are two distinct forms of thrombosis:
If a bacterial infection is present at the site of thrombosis, the thrombus may break down, spreading particles of infected material throughout the
Circulatory System (
Pyemia ,
Septic Embolus ) and setting up metastatic abscesses wherever they come to rest. Without an infection, the thrombus may become detached and enter circulation as an
Embolus , finally lodging in and completely obstructing a blood vessel (an
Infarction ). The effects of an infarction depend on where it occurs.
Most thrombi, however, become
Organized Into Fibrous Tissue , and the thrombosed vessel is gradually recanalized.
