last updated 24-06-2024

Arterial and venous thrombosis


Thrombosis is a major cause of death. It causes arterial occlusion resulting in myocardial infarction, stroke or ischemia and venous occlusion leading to deep venous thrombosis or pulmonary embolism.

Endothelial injury is the main cause of arterial thrombosis. Thrombi form at sites with underlying arterial wall pathology e.g. arteriosclerosis. Rupture of the arteriosclerotic lesion induces adhesion and activation of platelets and inflammatory cells induce the release of tissue factor (TF). Venous thrombosis is caused mainly by stasis and hypercoagulability.



Several risk factors for venous thrombosis have been identified:

  • Acquired risk factors: immobilization, operation, trauma, plaster, pregnancy, smoking, oral contraception, age, and malignancy.
  • Genetic risk factors: deficiencies of natural anticoagulants (antithrombin, protein C and protein S deficiency), factor V Leiden and prothrombin 20210A mutation, blood group non-O.

Thrombosis can be caused by 


Which of the following statements is true? 


Dilatation of the peripheral arterial blood vessels can be caused by