Cholesterol Emboli

Excerpt

Cholesterol embolism or atheroembolism is a phenomenon where cholesterol crystals and atheroma debris, such as cholesterol, platelets, and fibrin, embolize from proximal large arteries, such as the aorta and its major branches, to distal small arteries. Cholesterol emboli result from a fracture of an atherosclerotic plaque. Cholesterol emboli should be suspected in patients with worsening renal function, hypertension, acute multisystem dysfunction, or distal ischemia after an invasive arterial procedure. Cholesterol embolism frequently occurs after intraarterial procedures but can also happen spontaneously. Cholesterol embolism is an uncommon multisystemic disease involving multiple organs, including the brain, muscles, skin, eyes, kidneys, and gastrointestinal (GI) tract.

Organ damage usually manifests when cholesterol crystals break off from atherosclerotic plaques and shower to downstream vascular beds, causing mechanical obstruction and inflammatory response to the target organ. It is important to note that cholesterol embolism is separate from thromboembolism, in which a thrombus forms on top of atherosclerotic plaque and large emboli break off, causing sudden infarction. In contrast, cholesterol embolism is a more gradual process and causes end-organ damage over time. The emboli are usually made of debris from atherosclerotic plaques, mainly cholesterol crystals.

Another name for cholesterol embolism syndrome or atheroembolism is "blue toe syndrome." This syndrome is caused by atheroembolism that occludes the digital vasculature. In this disease, embolisms usually occlude smaller diameter vessels, and peripheral pulses are often intact. Therefore, whenever distal gangrene, ulcers, and cyanosis are present with intact pulses, it is highly suggestive of blue toe syndrome.