Laparoscopic splenectomy for patients with portal hypertension is associated with a high risk of bleeding. The use of vessel-sealing devices and automatic sutures is important for bleeding control. However, a rare complication of abdominal surgery is the direct communication between the arterial and portal circulation related to surgical procedures such as simultaneous ligature of an artery and adjacent vein. We describe a rare case of omental arteriovenous fistula (AVF) after laparoscopic splenectomy treated with transarterial embolization.

We report a case of a 46-year-old male patient with an omental AVF after a laparoscopic splenectomy 6 years ago for splenomegaly associated with alcoholic cirrhosis. Follow-up abdominal dynamic computed tomography accidentally revealed a vascular sac (25 mm in the major axis) that formed an omental AVF with anastomosis to the left colonic vein. The communication was considered to be caused by using a vessel-sealing device. No symptoms related to the AVF were observed. The AVF was embolized with microcoils using the transarterial approach. A 4-axis catheter system was used for accurate embolization due to the long and tortuous distance from the celiac artery. No recurrence or symptoms were observed after 6 months.

Treatment of arterioportal fistula is mandatory, even in asymptomatic patients. Embolization is a less invasive alternative to surgical approaches. The 4-axis catheter system was useful for accurate embolization via a long and tortuous artery.

Fistula formation is a severe adverse event related to antiangiogenetic agents such as bevacizumab and inferior mesenteric arteriovenous fistula (IMAVF) is a result of acquired factor, especially colon surgery. However, IMAVF occurs very rarely and there are few reports in patients during chemotherapy. We report a case of a patient who developed IMAVF during treatment with bevacizumab in metastatic colorectal cancer (mCRC) after colon surgery.

An 81-year-old man was diagnosed with descending colon cancer and underwent left hemicolectomy without any complications. He was definitely diagnosed with high-risk stage 2 and received tegafur-uracil plus leucovorin as adjuvant chemotherapy. Three years and 6 mo after the operation, the cancer relapsed with peritoneal dissemination. The patient underwent CyberKnife radiosurgery targeting the recurrent tumor and received chemotherapy with S-1 plus bevacizumab. At 1 year after chemotherapy, he complained of severe diarrhea, which is suspected drug-induced colitis. As diarrhea worsened despite the termination of treatment, he underwent colonoscopy and computed tomography (CT) scans that revealed edematous change from sigmoid to rectosigmoid colon. CT scans also revealed an aneurysm adjacent to the inferior mesenteric vein and multidetector CT angiography showed the IMAVF. Elective angiography confirmed the diagnosis of an IMAVF and it was successfully treated by arterial embolization. The patient resumed chemotherapy with only S-1 6 mo after embolization.

Clinicians should keep in mind the probability of severe diarrhea arose from IMAVF in mCRC patients treated with bevacizumab.

We report a very rare case of rectal arteriovenous fistula following sigmoidectomy and discuss this case in the context of the existing literature. In April 2011, the patient, a man in his 60s, underwent laparoscopic sigmoidectomy with lymph node dissection for sigmoid colon cancer. Beginning in February 2012, he experienced frequent diarrhea. Abdominal contrast-enhanced CT revealed local thickening of the rectal wall and rectal arteriovenous fistula near the anastomosis site. Rectitis from the rectal arteriovenous fistula was diagnosed. No improvement was seen with conservative treatment. Therefore, surgical resection was performed laparoscopically and the site of the lesion was confirmed by intraoperative angiography. The arteriovenous fistula was identified and resected. Postoperatively, diarrhea symptoms resolved, and improvement in rectal wall thickening was seen on abdominal CT. No recurrence has been seen as of 1 year postoperatively.

A 51-year-old man suffered from bleeding esophageal varices. He had undergone partial gastrectomy for gastric cancer 1 year before. An extrahepatic arterioportal fistula and resultant portal hypertension were found. We successfully performed transarterial embolization of the fistula using stainless steel coils. Portal hypertension improved dramatically.

Iatrogenic arteriovenous fistula of the superior mesenteric vessels is rare, with only 22 cases being documented. We report herein a case of a 63-year-old man with an iatrogenic arteriovenous fistula which developed after a small bowel resection for intestinal tuberculosis. The patient was admitted to our hospital for a gastric ulcer, at which time an ultrasonogram demonstrated cystic dilatation of the superior mesenteric vein, proving to be an arteriovenous fistula of the mesenteric vessels. An angiogram of the superior mesenteric vessels subsequently confirmed this diagnosis and resection of the fistula was performed, followed by an uneventful recovery. Iatrogenic mesenteric arteriovenous fistula with no presenting symptoms, as in our case, is uncommon and surgery performed before the development of associated portal hypertension should achieve good results. A review of the literature follows the report of this case.

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.

Iatrogenic arteriovenous fistulas (AVF) in infancy are rare and are usually located at the level of femoral and antecubital vessels. They are generally secondary to multiple diagnostic or therapeutic arterial or venous punctures. The diagnosis is usually easy to make on clinical grounds; however, invasive procedures such as digital subtraction angiography (DSA) can be used to locate the fistula. These iatrogenic AVF may present as direct vascular communications or pseudoaneurysms originating in the venous wall. Surgical treatment is the therapy of choice. The case of an infant with an iatrogenic AVF of the femoral vessels is presented.

Visceral arteriography was performed in 35 adult patients who had undergone various types of gastric surgery. Nineteen of these patients had presented with gastrointestinal hemorrhage at different postoperative intervals (4 days-23 years). Arteriography showed the bleeding site in 14 (74%) and permitted its nonoperative control in 8 cases. Diffuse hemorrhage from the gastric pouch as well as localized bleeding from suture line, marginal or stress ulcers, and other sources were recognized. Arteriography was also crucial in the diagnosis of iatrogenic arteriovenous fistulas, telangiectasia in the anastomotic regions, inadvertently ligated arteries, and postoperative changes in the vascular architecture. Value and limitations of arteriography of the postsurgical stomach are presented together with a review of the pertinent literature.

An arteriovenous fistula of the right internal mammary artery and vein following median sternotomy was demonstrated by angiography. This surgical complication has not been previously reported in the literature, despite the recent increase in cardiac surgery via median sternotomy. Clinical and radiologic awareness of this iatrogenic shunt and of its potential delayed appearance and cardiovascular effects are important. Arteriovenous fistulas are usually treated by surgical ligation and excision, or by transcatheter occlusion therapy.

Twenty-two cases of arteriovenous fistulae are reviewed retrospectively, with particular emphasis on their clinical presentation, physical signs, investigations and management. This review allows us to make certain conclusions for the future diagnosis and management of this condition.