Endoscopic ultrasound-guided precise embolization for refractory abdominal arteriovenous malformation

Endoscopic ultrasound-guided precise embolization for refractory abdominal arteriovenous malformation Arteriovenous malformations (AVMs) are abnormal fistulas between arteries and veins without an intervening capillary bed [1], which may lead to a variety of symptoms as they progress [2].The primary treatments, including surgical resection and transcatheter arterial embolization, still carry risks like bleeding and incomplete resection [3,4].Here, we present a case of a refractory AVM treated with an endoscopic ultrasound (EUS)guided devascularization technique.A 38-year-old man was admitted with abdominal discomfort lasting one month.Contrast-enhanced computed tomography (CT) and digital subtraction angiography (DSA) revealed an abdominal AVM involving the common hepatic artery and the portal vein.The patient underwent DSA-guided transarterial embolization, and most of the AVM was occluded ( Fig. 1).However, on the second day post-embolization, he developed severe abdominal pain, and an emergency CT indicated acute pancreatitis and a hepatic ectopic embolism.Despite standardized treatment, he experienced recurrent pain and significant weight loss.Follow-up CT and EUS identified an 8.5 6.8-cm pseudocyst in the pancreatic head and an approximately 4.0-cm residual AVM ( Fig. 2).To alleviate symptoms, we performed EUS-guided aspiration of the pseudocyst and placed a pancreatic duct stent.Given the increasing size of the residual fistula and the complications from previous interventions, we opted for EUS-guided embolization of the residual AVM ( Video 1).Using a 22-gauge needle, we punctured the fistula cavity and sequentially deployed two coils (Boston Scientific, Marlborough, Massachusetts, USA), followed by consecutive injections of lauromacrogol and Histoacryl.EUS confirmed hyperechoic filling Fig. 1 Abdominal computed tomography (CT) and digital subtraction angiography (DSA) images around the abdominal arteriovenous mal- formation.a, b Enhancement CT and DSA image showed the presence of arteriovenous malformations (AVMs) between the common hepatic artery and portal vein.c DSA image after interventional embolization.d CT scan showed the hepatic ectopic embolism after transarterial embolization.e CT scan showed multiple effusions around the pancreas and residual arteriovenous fistulas. Fig. 2 CT and endoscopic ultrasound (EUS) scan revealed the pseudocyst and residual arteriovenous fistula.a CT scan revealed a pseudocyst located in the pancreatic head.b Enhanced CT showed the residual arteriovenous fistula near the pancreatic head.c EUS with color Doppler revealed the inflow of the arteriovenous fistula. Fig. 3 EUS and CT images at the 6-month follow-up after EUS-guided embolization.a EUS with color Doppler showed the complete occlusion of the arteriovenous fistula.b CT showed the complete occlusion of the arteriovenous fistula.