A Case of Segmental Arterial Mediolysis Presenting with Retroperitoneal Hemorrhaging

Abstract

A 53-year-old man visited a local clinic with sudden onset of abdominal pain and thereafter he was referred to our hospital for further examination. CT imaging showed the presence of a retroperitoneal hematoma measuring 15cm in diameter around the right anterior pararenal space. Emergency angiography showed multiple aneurysms in the branches of the jejunal artery, left gastric artery and inferior gastroduodenal artery and extravasation of contrast medium was detected from the posterior inferior pancreatoduodenal artery. TAE was performed, but adequate hemostasis could not be obtained. Thus, operative hemostasis was selected and a ligation of the posterior pancreatoduodenal artery was performed. After the operation, stenosis of the duodenum due to ischemia occurred, but it could be successfully treated endoscopically. This patient was diagnosed as having segmental arterial mediolysis (SAM) based on his clinical features. SAM is a rare arteriopathy of unknown origin and it is usually found when intraabdominal hemorrhage occurs caused by rupture of an aneurysm. Conservative treatment with IVR is sometimes anatomically difficult in a case of rupture of branches of the pancreaticoduodenal artery and various complications might occur after TAE. When treating SAM of branches of the pancreaticoduodenal artery accompanied by rupture, it is important to select the optimal treatment including surgery.