Superior mesenteric artery embolism

Superior mesenteric artery embolism refers to the condition in which various emboli shed from other sites travel through the bloodstream to the superior mesenteric artery and lodge at its terminal portion, resulting in impaired blood supply to that artery and acute ischemic necrosis of the supplied intestinal segment. The main trunk of the superior mesenteric artery is relatively large in caliber and forms an oblique angle with the abdominal aorta, making it easy for emboli to enter. Therefore, this condition is relatively common clinically, accounting for approximately 40% to 50% of acute mesenteric ischemia. Emboli generally originate from mural thrombi in the heart, and are therefore more common in patients with rheumatic heart disease, coronary heart disease, infective endocarditis, and recent myocardial infarction. In addition, emboli may originate from atherosclerotic plaques and, occasionally, bacterial emboli. These emboli may dislodge spontaneously or during catheter examination.