Carbon Dioxide-Enhanced Angiography for Detection of Colonic Diverticular Bleeding and Clinical Outcomes

Purpose: To determine the ability of CO ₂ -enhanced angiography to detect active diverticular bleeding that is not detected by iodinated contrast medium (ICM)-enhanced angiography and its impact on clinical outcomes when used to confirm embolization, particularly the risks of rebleeding and ischemic complications. Materials and Methods: We retrospectively identified a cohort of patients with colonic diverticular bleeding who underwent catheter angiography between August 2008 and May 2023 at our institution. We divided them according to whether they underwent CO ₂ angiography following a negative ICM angiography study or to confirm hemostasis post-embolization (the CO ₂ angiography group) or ICM angiography alone in the absence of active bleeding or for confirmation of hemostasis post-embolization (the ICM angiography group). The ability to detect active colonic diverticular bleeding and clinical outcomes were compared between the two groups. Results: There were 31 patients in the ICM angiography group and 29 in the CO ₂ angiography group. The rate of detection of active bleeding by CO ₂ angiography that was not identified by ICM angiography was 48%. The rebleeding rate was 23% in the ICM angiography group and 6.9% in the CO ₂ angiography group. Among the patients who underwent TAE, the ischemic complications rate was 7.1% in the ICM angiography group and 4.5% in the CO ₂ angiography group. Conclusions: CO ₂ angiography may detect active diverticular bleeding that is not detectable by ICM angiography and appears to be associated with a lower rebleeding rate. Level of evidence: IV