Arterial Embolism

Most common sources are thrombus or vegetation in the heart or aorta, or paradoxically from a venous thrombus through a right-to-left intracardiac shunt.

History

Sudden pain or numbness in an extremity in the absence of previous history of claudication.

Physical Examination

Absent pulse, pallor, and decreased temperature of limb distal to the occlusion. Diagnosis confirmed by CT, MR, or conventional angiography.

Atheroembolism

A subset of acute arterial occlusion due to embolization of fibrin, platelets, and cholesterol debris from more proximal atheromas or aneurysm; typically occurs after intraarterial instrumentation. Depending on location, may lead to stroke, renal insufficiency, or pain and tenderness in embolized tissue. Atheroembolism to lower extremities results in blue toe syndrome, which can progress to necrosis and gangrene. Treatment is supportive; for recurrent episodes, surgical intervention in the proximal atherosclerotic vessel or aneurysm may be required.

Thromboangiitis Obliterans (Buerger's Disease)

Typically occurs in men age <40 who are heavy smokers and involves both upper and lower extremities; non-atheromatous inflammatory reaction develops in veins and small arteries, leading to superficial thrombophlebitis and arterial obstruction with ulceration or gangrene of digits. Imaging with CT, MR, or conventional angiography shows smooth tapering lesions in distal vessels, often without proximal atherosclerotic disease. Abstinence from tobacco is essential.

Vasospastic Disorders

Manifest by Raynaud's phenomenon in which cold exposure results in triphasic color response: blanching of the fingers, followed by cyanosis, then rubor. Most often a benign disorder. However, suspect an underlying disease (Table 128-1 Classification of Raynaud's Phenomenon) if tissue necrosis occurs, if disease is unilateral, or if it develops after age 50.