There are several possible causes of intestinal ischemia and infarction.
Hernia: If the intestine moves into the wrong place or becomes tangled, this can lead to intestinal ischemia.
Adhesions: The intestine may become trapped in scar tissue from past surgery (adhesions). This can lead to ischemia if left untreated.
Embolus: A blood clot from the heart or main blood vessels may travel through the bloodstream and block one of the arteries supplying the intestine. People who have had a heart attack or who have arrhythmias, such as atrial fibrillation, are at risk for this problem.
Arterial thrombosis: The arteries that supply blood to the intestine may become so narrowed from atherosclerotic disease (cholesterol buildup) that they become blocked. When this happens in the arteries to the heart, it causes a heart attack. When it happens in the arteries to the intestine, it causes intestinal ischemia.
Venous thrombosis: The veins carrying blood away from the intestines may become blocked by blood clots. This blocks blood flow into the intestines. This is more common in people with liver disease, cancer, or blood clotting disorders.
Low blood pressure: Very low blood pressure in patients who already have narrowing of the intestinal arteries may also cause intestinal ischemia. This typically occurs in patients who are very ill for other reasons. It can be compared to losing water pressure in a hose with a partial blockage.