DefinitionArterial embolism is a sudden interruption of blood flow to an organ or body part due to a clot (embolus).
Causes, incidence, and risk factorsAn embolus is a blood clot or a piece of plaque that acts like a clot. Emboli means more than one clot or piece of plaque. When 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 in the heart, causing a heart attack. Less common sites include the kidneys, intestines, and eyes.Atrial fibrillation is a major risk factor for arterial embolism. The risk of an embolism increases when factors that tend to form clots are increased. Other risk factors include injury or damage to an artery wall and conditions that increase blood clotting (such as severely 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 arterial emboli.A common source for an embolus is from areas of hardening (atherosclerosis) in the aorta and other large blood vessels. These clots can break loose and flow down to the legs and feet.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 move to an artery and block 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.
SymptomsYou may not have any symptoms. Symptoms may begin quickly or slowly depending on the size of the embolus and how much it blocks the blood flow.Symptoms of an arterial embolism in the arms or legs may include:Cold arm or legDecreased or no pulse in an arm or legFingers or hands feel coolLack of movement in the arm or legMuscle pain in the affected areaMuscle spasm in the affected areaNumbness and tingling in the arm or legPale color of the arm or leg (pallor)Weakness of an arm or legLater symptoms:Blisters of the skin fed by the affected arteryShedding (sloughing) of skinSkin erosion (ulcer)Tissue death (necrosis; skin is dark and damaged)Symptoms of a clot in an organ vary with the organ involved but may include:Pain in the part of the body that is involvedTemporarily decreased organ function
Signs and testsThe health care provider may find decreased or no pulse, and decreased or no 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:Angiography of the affected extremity or organDoppler ultrasound exam of an extremityDuplex Doppler ultrasound exam of extremityEchocardiogramMRI of the arm or leg
Myocardial contrast echocardiography (MCE)PlethysmographyTranscranial Doppler exam of arteries to the brainTransesophageal echocardiography (TEE)This disease may also affect the results of the following tests:Euglobulin lysis time (ELT)Factor VIII assayIsotope study of the affected organPlasminogen activator inhibitor-1 (PAI-1) activityPlatelet aggregation testTissue-type plasminogen activator (t-PA) levels
TreatmentArterial embolism requires prompt treatment at a hospital. The goals of treatment are to control symptoms and to improve the interrupted blood flow to the affected area of the body. The cause of the clot, if found, should be treated to prevent further problems.Medications include:Anticoagulants (such as warfarin or heparin) can prevent new clots from formingAntiplatelet medications (such as aspirin or clopidogrel) can prevent new clots from formingPainkillers given through a vein (by IV)Thrombolytics (such as streptokinase) can dissolve clotsSome people need surgery. Procedures include:Bypass of the artery (arterial bypass) to create a second source of blood supplyClot removal through a balloon catheter placed into the affected artery or through open surgery on the artery (embolectomy)Opening of the artery with a balloon catheter (angioplasty) with or without a stent
Expectations (prognosis)How well a patient does depends on the location of the clot and how much the clot has blocked blood flow. Arterial embolism can be serious if not treated promptly.The affected area can be permanently damaged. Up to approximately 25% of cases require amputation.Arterial emboli can come back (recur) even after successful treatment.
ComplicationsAcute MIInfection in the affected tissueSeptic shockStroke (CVA)Temporary or permanent decrease or loss of other organ functionsTemporary or permanent kidney failureTissue death (necrosis) and gangreneTransient ischemic attack (TIA)
Calling your health care providerGo to the emergency room or call the local emergency number (such as 911) if you have symptoms of arterial embolism.
PreventionPrevention begins with identifying the source of the blood clot. If your health care provider determines you have a high risk for blood clots, you may be prescribed blood thinners (such as warfarin or heparin) to prevent them from forming. Antiplatelet drugs may also be needed.You have a higher risk atherosclerosis and clots if you are:A smoker Inactive and do little exerciseOverweightStressed
ReferencesGoldman L. Approach to the patient with possible cardiovascular disease. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 50.Rooke TW, Hirsch AT, Misra S, et al. 2011 ACCF/AHA Focused Update of the Guideline for the Management of Patients With Peripheral Artery Disease (Updating the 2005 Guideline). J Am Coll Cardiol. 2011;58:2020-2045.Sobel M, Verhaeghe R. Antithrombotic therapy for peripheral arterial occlusive disease: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 2008;133(6):815S-843S.