Complete Occlusion of the Abdominal Vasculature: A Case of Chronic Mesenteric Ischemia

Abstract

Chronic mesenteric ischemia (CMI) accounts for 5 % of intestinal ischemic diseases, almost always caused by mesenteric atherosclerosis, although rare causes such as collagen vascular disease and inflammatory vasculopathy are known. There is no specific association between CMI and smoking, although 75% of patients have a history of smoking. A 44-year old farmer, with a 40-pack year history of smoking and no comorbidities, presented with abdominal pain, loose stools, melena and a 130 pound weight loss over the past two years. He was grossly emaciated with temporal muscle wasting. Routine investigations showed a hemoglobin of 14.5 gms/dl, WBC of 10,500 c/mm3, LDH of 184 mU/ml, ESR of 28 mm/hour, normal transaminases and ALP of 139 mU/ml. A CT angiography of the abdomen showed severe stenosis of the celiac trunk (CA) and complete occlusion of the superior mesenteric artery (SMA) and inferior mesenteric artery (IMA). Upper endoscopy showed gastric erthyema. Colonoscopy showed patchy mild active ileitis. ANA, ANCA and anti-TTG were negative. The patient was diagnosed with chronic mesenteric ischemia. A digital subtraction angiography showed 100 % stenosis of the SMA and IMA. A retrograde mesenteric bypass was performed by vascular surgery. The patient demonstrated a significant improvement in his symptoms and gained 4 pounds in one week. The cardinal clinical feature of CMI is abdominal cramps within 30 minutes after a meal, gradually increasing in severity and resolving over 1-3 hours. The fear of eating results in weight loss. Continuous pain portends intestinal infarction. Uncommon presentations of CMI include antral ulcerations unassociated with H. Pylori which do not heal with PPI's; gastroparesis and acalculous cholecystitis. The abdomen typically remains soft and non-tender even during painful episodes. A duplex ultrasound (USG) can be used to identify splanchnic artery stenoses. Elevated peak systolic velocity in the SMA and CA of 275 and 200 cm/sec respectively, is a reliable sign of at least 70 % stenosis of these vessels. Surgical revascularisation is the standard treatment with percutaneous transluminal mesenteric angioplasty (PTMA) being used in poor surgical candidates. A patient with characteristic symptoms and unexplained weight loss whose diagnostic evaluation has excluded other gastrointestinal disease and whose angiogram show occlusive involvement of at least two of the three major arteries, should undergo revascularisation.Figure: CT angiography demonstrating occlusion of the inferior mesenteric artery (IMA).Figure: CT angiography demonstrating occlusion of the superior mesenteric artery (SMA).