Pseudocyst development is a common complication of chronic pancreatitis. Endoscopic cystogastrostomy is an alternative to percutaneous drainage of pancreatic pseudocysts. Endoscopic ultrasound (EUS) guidance is thought to decrease the procedural risk by identifying and avoiding intervening vasculature. With EUS guidance, extreme care should be exercised to identify large gastric vessels in the path of the puncture. Preoperative imaging should be closely scrutinized for the presence of these vessels. In cases of hemorrhage, balloon tamponading is a rapid way to provide temporary control, allowing transfer of the patient for angiographic embolization. We present a case of arterial hemorrhage due to inadvertent puncture of a hypertrophied right gastric artery following EUS-guided cystogastrostomy, which was successfully treated with temporary balloon occlusion and coil embolization.

Keywords: pancreatic pseudocyst • endoscopy • hemorrhage • ultrasonography