Ruptured Pseudoaneurysm of Right Hepatic Artery as Immediate Complication of Lumen-Apposing Metal Stent Placement for Choledochoduodenostomy: A Case Report.

Endoscopic ultrasound-guided biliary drainage with lumen-apposing metal stents (LAMS) is an effective alternative for the management of malignant biliary obstruction. Despite its effectiveness, the procedure carries risks including rare but severe vascular complications. We report the first case of a ruptured pseudoaneurysm of the right hepatic artery as an immediate complication of LAMS placement and subsequent covered self-expanding metal stent (cSEMS) placement. A 63-year-old female with unresectable metastatic pancreatic adenocarcinoma was admitted to our hospital with worsening abdominal pain and jaundice. Imaging revealed biliary ductal dilation and a pancreatic mass involving major vascular structures. Owing to failed endoscopic retrograde cholangiopancreatography, EUS-guided choledochoduodenostomy with LAMS placement was performed. Immediately after LAMS deployment, massive bleeding occurred, which was controlled with an additional cSEMS. Despite the initial stabilization, subsequent gastrointestinal bleeding was observed. Computed tomography angiography (CTA) revealed a right hepatic artery pseudoaneurysm that required emergent arterial embolization. This case highlights a super rapid pseudoaneurysm formation following rescue cSEMS placement for the bleeding caused by LAMS placement.