Arterial embolism is a sudden interruption of blood flow to an organ or body part due to a clot (embolus).

An embolus is a blood clot or a piece of plaque that acts in the same manner as a clot. Emboli means more than one clot. If the clot travels from the site where it formed to another location in the body it is called an embolism.

An arterial embolism may be caused by one or more clots. The clots can get stuck in an artery and block blood flow. The blockage starves tissues of blood and oxygen, which can result in damage or tissue death (necrosis).

Arterial emboli often occur in the legs and feet. Some may occur in the brain, causing a stroke, or the heart, causing a heart attack. Less common sites include the kidneys, intestines, and the eyes.

Atrial fibrillation is a major risk factor for an arterial embolism. The risk of an embolism increases when factors that tend to form clots are increased. Such factors may include injury or damage to an artery wall and conditions that increase blood clotting (such as increased platelet count).

Another condition that poses a high risk for embolization (especially to the brain) is mitral stenosis. Endocarditis (infection of the inside of the heart) can also cause an arterial emboli.

Paradoxical embolization can take place when a clot in a vein enters the right side of the heart and passes through a hole into the left side. The clot can then cause blockage of blood flow to the brain (stroke) or other organs.

If a clot involves the arteries supplying blood flow to the lungs, it is called a pulmonary embolus.

Symptoms may begin abruptly or slowly depending on the size of the embolus and the extent to which it blocks the blood flow.

Symptoms of an arterial embolism in the arms or legs may include:

• Muscle pain in the affected area
• Muscle spasm in the affected area
• Numbness and tingling in the arm or leg
• Pale color of arm or leg
• Decreased or absent pulse in the extremity
• Cold arm or leg
• Lack of movement of the extremity
• Weakness of arm or leg
• Fingers or hands feels cool
• Loss of muscle function

Later symptoms:

• Blisters
• Skin erosion (ulcer)
• Tissue death (necrosis; skin is dark and damaged)
• Sloughing of skin

Symptoms of a clot in an organ vary with the organ involved but may include:

• Pain
• Temporarily decreased organ function
• Ischemia (lack of oxygen)
• Infarction (tissue death)

There may be decreased or absent pulse, and decreased or absent blood pressure in the arm or leg. There may be signs of tissue death or gangrene.

Tests to diagnose arterial embolism or reveal the source of emboli may include:

• Doppler ultrasound exam of an extremity
• Transcranial Doppler
• Echocardiogram
• Transesophageal echocardiography (TEE)
• Myocardial contrast echocardiography (MCE)
• MRI
• Angiography of the affected extremity or organ
• Renal arteriography
• Extremity arteriography
• Plethysmography
• Duplex Doppler/ultrasound exam of extremity

This disease may also alter the results of the following tests:

• Isotope study
• Platelet aggregation test
• Factor VIII assay
• Euglobulin lysis time (ELT)
• Plasminogen activator inhibitor-1 (PAI-1) activity
• Tissue-type plasminogen activator (t-PA) levels