Superior Mesenteric Arteriovenous Fistula Presenting with Massive Lethal Upper Gastrointestinal Bleeding 14 Years after Small Bowel Resection

Abstract

Superior mesenteric arteriovenous fistula (SMAVF) is an extremely infrequent vascular disorder. It is characterized by abnormal, direct communication between high-pressure superior mesenteric artery (SMA) and low-pressure superior mesenteric vein (SMV). This shunt allows blood to bypass the intestinal capillary bed and produces hypertension in the portal circulation. Although SMAVF can be congenital, the majority of cases reported have been due to abdominal trauma or iatrogenic causes. These fistulas originate from an undetected injury to SMA and SMV and can present several days to several years later, usually following bowel-related surgery. Manifestations of SMAVF include a wide variety of symptoms such as mild abdominal pain, diarrhea and weight loss. Due to the often obscured presence of the fistula, complications related to long-standing arteriovenous (AV) shunt and high portal blood pressure are potentially fatal. The most serious complications are congestive heart failure and portal hypertension, which may lead to gastro-esophageal variceal bleeding (1). General mortality for untreated cases of portal arteriovenous fistula (AVF) is estimated at about 26% (2). Here, we report a case of delayed presentation of acquired SMAVF in a male adult after small bowel resection.

Endovascular Repair of Superior Mesenteric Arteriovenous Fistula Causing Early Mesenteric Steal Syndrome Following Abdominal Gunshot Injury

“…SMAVFs are most often the result of traumatic or iatrogenic injury, although other causes include ruptured aneurysms, infections, or congenital malformation. 2 , 3 In traumatic SMAVF the clinical presentation is usually delayed, with some patients remaining asymptomatic for many years. Presenting symptoms typically comprise abdominal pain, nausea, vomiting, and diarrhoea, presumably due to a combination of intestinal ischaemia and portal congestion.…”

“…Less commonly, increased portal venous pressure gives rise to hepatic congestion, variceal haemorrhage, ascites, and right heart failure. 3 …”

“…However, use of covered stents is recommended as embolisation in this context carries a significant risk of coil migration, distal enteric arterial occlusion, or porto-mesenteric venous thrombosis. 2 , 3 Endovascular stent placement carries an increased risk of thrombosis, and therefore requires the patient to take long-term anticoagulant or antiplatelet therapy.…”

Endovascular treatment of an iatrogenic superior mesenteric arteriovenous fistula after Nissen fundoplication

“…SMAVF is most commonly caused by penetrating abdominal trauma or iatrogenic injury during abdominal surgery. Specifically, this complication has been observed after small bowel resection, colectomy, aortobifemoral bypass, and kidney-pancreas transplantation [3,4] . The clinical manifestations of SMAVF may vary from completely asymptomatic to nonspecific abdominal pain, anorexia, nausea, diarrhea, gastrointestinal hemorrhage, signs of portal hypertension, and even congestive heart failure secondary to a persistent high-flow state [5] .…”

An Extraordinary Cause of Dyspnea and Weight Loss

“…Mesenteric arteriovenous fistulae, although uncommon, have been reported after abdominal trauma and post bowel resection, often many years later. [1][2][3] To our knowledge, there have been no reported cases after intestinal transplantation. This case reiterates the importance of cross-sectional imaging in the assessment of patients with progressive symptomology after transplantation.…”