Ruptured cystic artery pseudoaneurysm after self-expandable metal stent placement for malignant biliary obstruction

We report a case of ruptured cystic artery pseudoaneurysm after self-expandable metal stent placement for malignant biliary obstruction. A 78-year-old woman on palliative care after chemotherapy for unresectable pancreatic head cancer presented with obstructive jaundice. Imaging revealed a dilated common bile duct and an enlarged gallbladder with cystic wall thickening. Endoscopic retrograde cholangiopancreatography was performed and a fully-covered self-expandable metal stent was placed in the bile duct, leading to resolution of jaundice. She presented with hematochezia 7 days later. Contrast-enhanced computed tomography revealed a cystic artery pseudoaneurysm with extravasation of contrast into a blood-filled gallbladder. Hemostasis was achieved after emergent transcatheter arterial embolization. Rupture of cystic artery pseudoaneurysm should be raised as a differential diagnosis for hemobilia after self-expandable metal stent placement, particularly in cases accompanied by inflamed gallbladders.