Impact of catheter location during mesenteric angiography in identifying sources of acute lower gastrointestinal bleeding

Objectives: The objective of this study was to compare the sensitivity of selective to superselective mesenteric angiography in identifying acute lower gastrointestinal bleeding (LGIB) after computed tomography angiography (CTA) demonstrating active arterial bleeding. Material and Methods: This is a single-center retrospective study of all patients who underwent mesenteric angiography to evaluate LGIB between January 2012 and September 2021. The inclusion criterion was a CTA demonstrating active arterial LGIB immediately before intervention. Patient demographics, etiology of bleeding, and procedural details were recorded. Selective angiography was defined as an ostial visceral branch injection; superselective was defined as any selection into or beyond a 2 nd order branch. Technical success was defined as the successful embolization of the target vessel. Clinical success was defined as the clinical resolution of gastrointestinal bleeding without additional procedural or surgical interventions within 30 days. Results: After inclusion criteria, 78 angiograms from 72 patients were evaluated. Active arterial bleeding was identified in 50% (39/78) of angiograms, and embolization was performed in 49% (38/78) of cases. The diagnostic sensitivity of superselective angiography was significantly greater than selective angiography (56.3% vs. 32.1%, P = 0.018). In 12.8% (10/78) of all angiograms, active bleeding was identified only with superselective angiography (25.6%, 10/39, of cases where any bleeding was identified). Embolization was performed in 38 of the angiograms; technical success was 97.4% (37/38), clinical success was 71.1% (27/38), and 26% (10/38) required further intervention. Embolization was not performed in 40 angiograms, with 68% (27/40) requiring an additional intervention. Conclusion: Superselective angiography is significantly more sensitive than selective angiography for patients with known acute LGIB identified on CTA.