Venous thrombosis

A venous thrombosis is a blood clot that forms within a vein. (Thrombosis is a specific medical term for a blood clot that remains in the place where it formed.)

Classification

Superficial venous thromboses can cause discomfort but generally do not cause serious consequences, unlike the deep venous thromboses (DVTs) that form in the deep veins of the legs or in the pelvic veins.

Since the veins return blood to the heart, if a piece of a blood clot formed in a vein breaks off it can be transported to the right side of the heart, and from there into the lungs. A piece of thrombus that is transported in this way is an embolism: the process of forming a thrombus that becomes embolic is called a thromboembolism. An embolism that lodges in the lungs is a pulmonary embolism (PE). A pulmonary embolus is a very serious condition that can be fatal if not recognized and treated promptly.

Systemic embolisms of venous origin can occur in patients with an atrial or ventricular septal defect, through which an embolus may pass into the arterial system. Such an event is termed a paradoxical embolism.

Risk factors

General
Older age
Female sex
Smoking
Obesity
Pregnancy
Immobilization
Minor injuries
Medical
Surgery
Trauma
Use of combined (containing both estrogen and progestin) forms of hormonal contraception
Varicose veins
Malignancy
Kidney disorders
Lupus anticoagulant
Paroxysmal nocturnal hemoglobinuria
Inflammatory bowel disease
Thromboangiitis obliterans (Mb Bürger)
Disseminated intravascular coagulation
Familial
Antithrombin III deficiency
Protein C deficiency/Protein S deficiency
APC resistance (Factor V Leiden)
Dysfibrogenemia
Hypoplasminogenemia
Familial hyperhomocysteinemia

Prevention

Vitamin E may prevent venous thrombosis.

Translation of "Venous thrombosis"

Hebrew: פקקת ורידים, Japanese: 静脈血栓塞栓症, Portuguese: Trombose venosa, Swedish: Ventrombos.