Ischemic Colitis: An Unusual Case of Inferior Mesenteric Arteriovenous Fistula Causing Venous Hypertension. Report of a Case

Mesenteric arteriovenous fistulas are a rare entity. Those involving the inferior mesenteric artery are exceptionally rare with only 13 cases reported in the English literature,1,2 of which only one has been associated with ischemic colitis. Ischemic colitis is a well-recognized clinical entity that typically occurs spontaneously in elderly patients and is not associated with a specific clinical presentation.3 We report a case of ischemic colitis caused by venous hypertension associated with a congenital inferior mesenteric arteriovenous fistula. To our knowledge, this is the first reported case of a mesenteric arteriovenous fistula causing ischemic colitis in a patient without previous gastrointestinal surgery or trauma. Reprints are not available.     

Ischemic colitis secondary to inferior mesenteric arteriovenous fistula and portal vein stenosis in a liver transplant recipient

Arteriovenous fistula （AVF） involving the inferior mesenteric vessels is rare, and the affected patients usually present with abdominal pain, mass, or features of established portal hypertension. Colonic ischemia is a less common and more serious manifestation of AVE We report a case of ischemic colitis secondary to inferior mesentedc AVF in a patient who underwent a previous liver transplantation, subsequently developed portal vein stenosis, and then presented with acute lower gastrointestinal bleeding. He underwent percutaneous transhepatic placement of a portal vein stent and left colectomy.     

Iatrogenic superior mesenteric arteriovenous fistula: Ultrasonographic, CT and angiographic features and histological findings of the liver biopsy

Iatrogenic superior mesenteric arteriovenous fistula is rare. We treated a patient with this problem 6 years after small bowel resection for intestinal obstruction. The symptoms and signs were those of intestinal ischaemia and portal hypertension with an abdominal bruit. Ultrasonography and enhanced computerized tomography of the abdomen suggested the presence of superior mesenteric arteriovenous fistula, with a dilated portal vein and a communication between the dilated superior mesenteric vein and its artery. The exact location of the fistula was then determined by selective superior mesenteric arteriography. The fistula was ligated in an emergency operation to prevent cardiac or renal failure and to relieve portal hypertension. Liver biopsy showed no cirrhotic changes, but fibrosis was seen around the portal veins. We describe here not only the diagnostic arteriographic findings of superior mesenteric arteriovenous fistula, but also the interesting and suggestive ultrasonographic and computed tomographic findings. Early correction of such fistulas is recommended to prevent cardiac or liver failure.     

Transcatheter embolization of an inferior mesenteric arteriovenous fistula with frequent mucous diarrhea]

We report a case of inferior mesenteric arteriovenous fistula without portal hypertension or mesenteric ischemia. A 64-year-old man had developed frequent mucous diarrhea during the previous month. Colonoscopy showed highly edematous mucosa of the rectum. Barium enema demonstrated localized stricture of the same part but no evidence of malignancy. Finally we established a diagnosis by 3D-CT and selective abdominal angiography. Transcatheter arterial embolization was successfully performed. After that, his symptoms gradually improved as all abnormal findings on colonoscopy, barium enema and abdominal CT disappeared.     

Inferior mesenteric arteriovenous fistula: Case report and world-literature review

Arteriovenous fistulas between the inferior mesenteric artery and vein are rare, with only 26 primary and secondary cases described in the literature. Secondary fistulas occur following operations of the left hemicolon and manifest as abdominal pain, abdominal mass, gastrointestinal bleeding, colonic ischemia and portal hypertension. Symptom intensities are flow-dependent, and can range from minimal symptoms to severe heart failure due to left to right shunt. Diagnosis is usually established by radiological or intraoperative examination. Treatment options include embolization and/or surgical resection. Therapeutic decisions should be adapted to the unique characteristics of the fistula on an individual basis. A new case of a primary arteriovenous fistula is described and discussed along with a complete review of the literature. The patient in this report presented with signs and symptoms of colonic ischemia without portal hypertension. The optimal treatment for this patient required a combination of embolization and surgical operation. The characteristics of these rare inferior mesenteric arteriovenous fistulas are examined and some considerations concerning diagnostic and therapeutic strategies that should be followed are presented.     

Gastrointestinal bleeding due to chronic portal vein thrombosis in ulcerative colitis

Summary The authors report the case of a patient suffering from ulcerative colitis, who had several episodes of digestive hemorrhage due to portal hypertension. Portal hypertension was secondary to chronic portal vein thrombosis. This diagnosis was made on the venous phase of celiac and mesenteric angiography. The authors review the published cases of ulcerative colitis with portal vein thrombosis and discuss the possible etiologic factors: hypercoagulability, thrombocytosis, and intraabdominal sepsis.     

Inferior mesenteric arteriovenous fistula eight years after sigmoidectomy

We report a 69-year-old woman with liver cirrhosis due to chronic hepatitis C virus (HCV) infection in whom iatrogenic arteriovenous fistula (AVF) developed after sigmoidectomy. A soft mass with bruit led to the diagnosis of inferior mesenteric AVF. Most mesenteric AVF cases have portal hypertension, but this patients showed none of the usual symptoms of portal hypertension; however, she had a splenomegaly that became worse after sigmoidectomy. Clinicians should be aware of the possibility of AVF in patients with a history of abdominal surgery.     

Splenic arteriovenous fistula causing massive ascites: a case report

A case of splenic arteriovenous fistula leading to portal hypertension and ascites is presented. The recognition of this vascular lesion is important. When portal hypertension is secondary to a splenic arteriovenous fistula, the complications of portal hypertension can be avoided by the resection of the lesion. The diagnosis can be suspected by clinical findings and confirmed by angiographic delineation of the fistula. Surgical resection of splenic arteriovenous fistulae must include the fistula and all dilated venous tributaries to prevent thrombosis and recurrent portal hypertension.     

Arterioportal Fistula: a Rare Cause of Portal Hypertension and Abdominal Pain

Esophageal varices are commonly caused by portal hypertension secondary to cirrhosis. We report the case of a 71-year-old woman who presented with esophageal variceal bleeding due to portal hypertension caused by an arteriovenous fistula. The fistula, which was probably brought about by a liver biopsy performed 18 years previously, was complicated by bleeding. Since this event, the patient has reported right upper quadrant pain. Embolization resulted in elimination of the varices as well as abdominal discomfort.     

Arterioportal fistula: a rare cause of portal hypertension and abdominal pain.

Esophageal varices are commonly caused by portal hypertension secondary to cirrhosis. We report the case of a 71-year-old woman who presented with esophageal variceal bleeding due to portal hypertension caused by an arteriovenous fistula. The fistula, which was probably brought about by a liver biopsy performed 18 years previously, was complicated by bleeding. Since this event, the patient has reported right upper quadrant pain. Embolization resulted in elimination of the varices as well as abdominal discomfort.     

Rectal arterio-portal fistula: An unusual cause of persistent bleeding per rectum following a proximal spleno-renal shunt

Gastrointestinal arterio-venous malformations are a known cause of gastrointestinal bleeding. We present a rare case of persistent rectal bleeding due to a rectal arterio-portal venous fistula in the setting of portal hypertension secondary to portal vein thrombosis. The portal hypertension was initially surgically treated with splenectomy and a proximal splenorenal shunt. However, rectal bleeding persisted even after surgery, presenting us with a diagnostic dilemma. The patient was re-evaluated with a computed tomography mesenteric angiogram which revealed a rectal arterio-portal fistula. Arterio-portal fistulas are a known but rare cause of portal hypertension, and possibly the underlying cause of continued rectal bleeding in this case. This was successfully treated using angiographic localizationand super-selective embolization of the rectal arterioportal venous fistula via the right internal iliac artery. The patient subsequently went on to have a full term pregnancy. Through this case report, we hope to high-light awareness of this unusual condition, discuss the diagnostic workup and our management approach.     

Arteriovenous fistula and forward hypertension in the portal circulation

The notorious predilection for rupture of splenic artery aneurysms in women of childbearing age is once more stressed by this case report. Although such ruptures usually result in a catastrophic interabdominal bleeding, in rare instances they lead to the formation of an arteriovenous fistula and consequent portal hypertension. Arterialization of the portal vein results in a progressive development of intrinsic hepatic morphologic changes and hepatoportal sclerosis, which further elevate the pressure in the portal system. This combination of pathophysiologic hemodynamic features closely resembles the original concept of Banti. He postulated that portal hypertension began with pathologic changes within the spleen which were associated with an increased blood flow through this organ. This led to increased flow and pressure in the portal venous system and ultimately cumulated in cirrhosis of the liver. This concept of the pathophysiology of portal hypertension has been universally abandoned, but it could serve as a model of the sequelae of an arteriovenous communication within the portal system.     

A case of ischemic colitis presenting as bloody diarrhea after normal saline enema]

Ischemic colitis is a frequent disorder of large bowel in elderly persons or in debilitated patients with a variable underlying medical problems. Ischemic colitis may result from alterations in the systemic circulation or anatomic or functional changes in the local mesenteric vasculature. In most cases, no specific cause for the ischemic colitis is identified. Cases of ischemic colitis after enema for bowel cleansing have been rarely reported, but there has been no case report after normal saline enema. We report a case of ischemic colitis in a 72-year old patient with well-controlled hypertension, presenting as bloody diarrhea which developed after normal saline enema for preoperative bowel cleansing.     

Melena-associated regional portal hypertension caused by splenic arteriovenous fistula

Regional portal hypertension is a rare cause of upper gastrointestinal bleeding. We reported an extremely rare case in which regional portal hypertension was associated with both the splenic arteriovenous fistula and chronic pancreatitis. In June 2010, our patient, a 41-year-old man, was admitted to a local hospital due to a sudden melena and dizziness without haematemesis and jaundice. The splenic arteriovenous fistula in this patient was successfully occluded through transcatheter arterial embolization. At the 12-mo follow-up, our patient was in good condition.     

Unusual case of digestive hemorrhage: Celiac axis-portal vein arteriovenous fistula

A case of intractable upper gastrointestinal-hemorrhage was reported in a patient with portal hypertension caused by an arterioportal fistula(APF), namely, celiac axis-portal vein arteriovenous fistula. Portal hypertension caused by extrahepatic-APFs is extremely rare. Trauma, malignancy, and hereditary causes are the common etiology of APFs; but were absent in our patient. Our patient represents an unusualcase of unexplained APF who presented with portal hypertension and was successfully managed through endovascular aortic repair.     

Successful arterial embolization of arteriovenous fistula in the portal circulation.

We successfully performed arterial embolization of an arteriovenous fistula between the left gastric artery and vein. The increased blood flow in the portal vein via the left gastric vein and the arteriovenous fistula induced severe portal hypertension. After obliteration of the left gastric artery, the arteriovenous fistula was not opacified on angiography and the portal hypertension improved.     

Pancreatic arteriovenous malformation combined with portal thrombosis

We encountered a case of portal vein thrombosis (PVT) after treatment for portal hypertension due to pancreatic arteriovenous malformation (PAVM). A 75-year-old man was admitted for the treatment of esophageal varices. Diffuse PAVM and aneurysm in the celiac and superior mesenteric arteries were detected via abdominal computed tomography and angiography. Although endoscopical sclerotherapy was performed, PVT was identified after the treatment and variceal bleeding continued. Autopsy was performed and the thrombus and malformation were pathologically confirmed. This case indicates that PVT can be associated with PAVM.     

A case of recurrent infection caused by a pancreaticoduodenal fistula associated with a pancreatic arteriovenous malformation

Although arteriovenous malformations (AVM) occur frequently in digestive organs, pancreatic AVM is rare. The clinical symptoms of pancreatic AVM are variable and include gastrointestinal bleeding, abdominal pain, jaundice, portal hypertension, pancreatitis, and duodenal ulcer. However, choledochoduodenal or pancreaticoduodenal fistulas complicated with ascending infection and pancreatitis is extremely rare. Herein, we report a case of pancreaticoduodenal fistula associated with a pancreatic AVM that induced recurrent anemia and ascending infection.     

Colorectal variceal bleeding in patients with extrahepatic portal vein thrombosis and idiopathic portal hypertension.

We report three patients with colonic variceal bleeding secondary to portal hypertension, 0.5% of all cases with hemorrhagic portal hypertension studied by us in the last 16 years. One patient had idiopathic portal hypertension, and the others had extrahepatic portal vein thrombosis. Colonic varices were documented in all three cases by angiogram; large arteriovenous fistulas in the territory of the superior mesenteric artery and between the inferior mesenteric artery and hemorrhoidal veins were demonstrated in one patient. Two patients underwent colonoscopy; colonic varices were seen in only one. Two patients also had bled from esophagogastric varices. One patient underwent descending colon and sigmoid resection after failure to control bleeding with ligation of arterial supply; one patient underwent the Sugiura procedure, plus transanal ligation of hemorrhoids and rectal varices. At 3 months, 2 years, and 4 years of follow-up, the patients were in good general condition without any evidence of rebleeding.     

A case of pulmonary arteriovenous fistula associated with multiple hepatic arterioportal shunts]

We report a case of pulmonary arteriovenous fistula with multiple hepatic arterioportal shunts. A 23-year-old man was admitted for evaluation of a nodular shadow in the right lower lung field. Chest CT showed a homogeneous and well-defined nodular shadow in the right S7. 3-dimensional CT revealed an arteriovenous fistula composed of a feeding artery and a draining vein in the right S7. Abdominal enhanced CT revealed a diffusely heterogeneous pattern in the liver parenchyma and the portal vein staining diffusely at the late arterial phase. We diagnosed pulmonary arteriovenous fistula associated with multiple hepatic arterioportal shunts. Pulmonary arteriovenous fistula is often associated with hereditary hemorrhagic telangiectasia (HHT). This case did not meet the criteria for HHT at this time. However, we could not exclude the possibility of HHT because clinical manifestations of HHT become apparent after 40 years old among 10% of patients. The natural history and treatment of HHT are not clear. We concluded that we should be careful to detect possible manifestations as HHT when we diagnose and follow up patients with pulmonary arteriovenous fistula.