Snap Shot A 70-year-old male with atrial fibrillation presents to the emergency department with sudden onset of severe abdominal pain despite relatively benign findings on physical exam. Introduction Ischemic injury from decreased mesenteric blood supply to intestinal tissue Mortality rate > 60% Causes Acute arterial occlusion Embolism (Afib, MI, valvular disease; 50% of cases) Thrombosis (atherosclerosis; 25% of cases) Non-occlusive arterial disease (20% of cases) Splanchnic vasoconstriction due to low CO Seen in critically ill patients Venous thrombosis (<10% of cases) Not to be confused with chronic mesenteric ischemia caused by mesenteric atherosclerosis, leading to poor perfusion in post-prandial states typically seen in patients with many other risk factors for atherosclerotic disease (PVD, CAD, HTN, Chronic renal disease) symptoms include weight loss, food aversion, and post-prandial pain Presentation Symptoms sudden onset of severe abdominal pain abdominal pain after eating ("intestinal angina") if due to arterial thrombosis nausea vomiting diarrhea mild GI bleeding Physical exam abdominal pain out of proportion to physical findings peritoneal signs if bowel is infarcted Evaluation Serology leukocytosis elevated lactate , amylase, LDH watch for signs of septic shock or organ failure Abdominal radiograph use AXR to rule out other causes of abdominal pain CT scan with angiography may reveal bowel wall edema or air within the bowel wall prefered first modality, as will illucidate other causes of abdominal pain. Mesenteric angiography gold standard for arterial occlusive disease Treatment Pharmacologic broad spectrum antibiotics avoid vasoconstrictors papaverine (vasodilator) if due to acute arterial disease thrombolytics if due to embolic disease heparin if due to venous thrombosis Surgical angioplasty and thrombectomy if due to thrombosis emergency laparotomy if evidence of bowel infarction or peritonitis is found may require resection of infarcted bowel