Use of CO2 Angiography in the Identification of the Bleeding Source of Colonic Diverticular Hemorrhage: A Case Report

Diverticular hemorrhage is the most common cause of lower gastrointestinal bleeding (LGIB). Because spontaneous hemostasis frequently occurs, identifying the bleeding diverticulum via colonoscopy or iodinated contrast angiography remains challenging. Recently, several reports have demonstrated the utility of CO2 angiography in identifying the bleeding source. The patient was a 73-year-old male referred to our hospital for hematochezia and was ultimately diagnosed with colonic diverticular hemorrhage. Despite repeated massive hemorrhage, spontaneous hemostasis prevented localization of the bleeding site; neither colonoscopy nor conventional iodinated contrast angiography detected the source. Finally, CO2 angiography was performed to successfully identify the bleeding site, which enabled transcatheter arterial embolization to achieve hemostasis. In cases of recurrent diverticular bleeding where the bleeding site remains undetectable, CO2 angiography may be an effective method to identify the source and guide targeted therapy.