Acute mesenteric ischemia and infarction is an emergent situation associated with high mortality, commonly due to emboli or thrombosis of the mesenteric arteries. Embolism to the mesenteric arteries is most frequently due to a dislodged thrombus from the left atrium, left ventricle, or cardiac valves. We report a case of 70-year-old female patient with an acute small bowel infarction due to a mesenteric artery embolism dislodged from a left atrial appendage detected by intraoperative transesophageal echocardiography and followed by anticoagulation therapy.