Gastric Arteriovenous Malformation: A Unique Case of a Rare Phenomenon

Abstract

Angiodysplasias are vascular lesions associated with predisposing conditions and are often culprits of gastrointestinal bleeds. True arteriovenous malformations are congenital and rare causes of intestinal bleeding. This case is unique in regards to its presentation of AVM disease. A 34 year old caucasian male with a history of obesity and alcohol abuse presented with hematemesis, melena, and fatigue for four days. He denied any abdominal pain or prior history of gastrointestinal bleeding. Initial hgb was 6.2; EGD was significant for a submucosal lesion with an overlying ulcer and visible vessel in the gastric fundus. EUS was done and exhibited a tortuous vessel arising from the left gastric vein within a thick gastric fold, concerning for gastric varix or congenital AVM. A CT Abdomen showed no evidence of cirrhosis or portal/splenic vein thrombosis. Emergent IR angiogram was performed for recurrent hematemesis revealing a dilated left gastric artery and early draining vein consistent with a congenital AVM; subsequent embolization of the left gastric artery was done. Hospital course was complicated by hematuria and diffuse alveolar hemorrhage and he was treated empirically with Cytoxan and steroids for possible underlying vasculitis, although diagnostic workup was inconclusive. He passed away from multi-organ failure. True AVMs of the GI tract are developmental defects that stem from obstinate communication between arteries and veins within the submucosa. Angiodysplasias are typically found in the ascending colon while AVMs are usually found in the rectum or sigmoid colon and very rarely involve the gastric mucosa with only a handful of cases reported in the literature. Within the umbrella of bleeding AVM disease, gastric involvement has only been seen in about 1% of cases mainly in patients above the age of 60. While EUS can assist with diagnosis, angiography remains the gold standard. Cases like this warrant investigation for unusual underlying diseases such as hereditary hemorrhagic telangiectasia, vasculitis, and amyloidosis which have occasionally been shown to be associated with intestinal arteriovenous malformations. The case described is distinctive not only in regards to the discovery of a true gastric arteriovenous malformation in a patient with no significant prior medical conditions but also due to its presentation at such a young age. Continued investigations of AVM disease are essential to assist the medical community in managing future cases.Figure: Initial EGD showing submucosal lesion with an overlying ulcer and visible vessel in the gastric fundus.Figure: EUS of gastric lesion significant for a 4 mm torturous vessel arising from the left gastric vein within a thick 2 cm gastric fold.Figure: Left gastric artery angiogram revealing dilated artery and early draining vein consistent with a congenital AVM.