Photo from National Geographic
This photo shows an angiogram of a human heart. Angiograms are performed on patients that are at risk for heart disease. First, the heart is injected with an opaque fluid, which shows up on x-rays. When an x-ray (angiogram) is taken, each individual artery becomes visible. Narrowed arteries can indicate coronary artery disease. Blockage, even incomplete blockage, of the two coronary arteries could cause a heart attack. Angiograms help doctors detect heart disease and recommend treatment.
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