Essence of this Article

When a thrombus forms within an artery, this is known as an arterial thrombosis. Arterial thrombi manifest as Myocardial Infarction (MI), unstable angina, ischaemic stroke and some manifestations of peripheral arterial disease, such as acute limb ischaemia. Risk factors for arterial thrombosis include smoking; obesity; high blood pressure; increasing age; and family history. The incidence and prevalence of the clinical manifestations of arterial thrombosis is high. The annual incidence of MI and stroke in the US in 2008 has been calculated to be 935,000 and 795,000, respectively.

Arterial Thrombi

coronary bypass thrombosis pathology

Coronary thrombosis.

When a thrombus forms within an artery, this is known as an arterial thrombosis.

Arterial thrombi:

  • Usually develop on top of an atherosclerotic plaque
  • Have a grey-white appearance, are firmly adherent and grow in the opposite direction from the point of attachment
  • Are composed of regularly arranged layers of platelets and fibrin, irregularly mixed with small amounts of darker red coagulated blood containing erythrocytes
  • Manifest as MI,47 unstable angina,48 ischaemic stroke49 and some manifestations of peripheral arterial disease, such as acute limb ischaemia50

Risk factors

Important risk factors for arterial thrombosis include:51

  • Smoking
  • Obesity
  • High blood pressure
  • Increased levels of cholesterol
  • Diabetes
  • Increasing age
  • Family history
  • Physical inactivity
  • Increased concentrations of blood coagulation factors
  • Blood serum lipid abnormalities

Incidence and prevalence

Cardiovascular disease is the leading cause of death in industrialized countries. Coronary artery disease (CAD) is the most common form of cardiovascular disease. In CAD, atherosclerosis damages the coronary artery wall predisposing to thrombus formation. The symptoms and severity of acute coronary syndromes (unstable angina and MI) vary depending on the degree to which thrombi occlude the coronary arteries.16, 52