Gastrointestinal Interventions

Session: Educational Exhibit Presentations - Station 4: Gastrointestinal Interventions

Hybrid Angiography-CT for the Localization of Obscure GI Bleeds and Utility in Guiding Treatment

Monday, March 6, 2023

5:30 PM – 5:35 PM

Location: Phoenix Convention Center, North Ballroom 120ABC, Poster Hall

Abstract Presenter(s)

KR

Kent Reichel, MD

Integrated IR/DR Resident
Johns Hopkins Hosptial

Disclosure(s): No financial relationships to disclose

Author/Co-author(s)

RR

Roy Ruttiman, MD

Integrated IR/DR Resident
Johns Hopkins Hospital
Kelvin Hong, MBBS

Divisional Director
Johns Hopkins Hospital
ML

Mark L. Lessne, MD

Vascular and Interventional Radiologist
Vascular & Interventional Specialists, Charlotte Radiology
BH

Brian Holly, MD

Program Director
Johns Hopkins Hospital

Disclosure(s):

Kent Reichel, MD: No financial relationships to disclose

Kelvin Hong, MBBS: ABBOTT, ANGIODYNAMICS, ANGIOSAFE, BD BARD, BOSTON SCIENTIFIC, CSI – FRONTIER, INTACT VASCULAR, ABBOTT, MEDTRONIC, MICRO MEDICAL SOLUTIONS, PLURISTEM, LTD SURMODICS, VERYAN, VESPER MEDICAL: Advisory Committee or Review Panel Member (Ongoing); Varian Interventional Solutions: Consultant (Ongoing)

Mark L. Lessne, MD: ABBOTT, ANGIODYNAMICS, ANGIOSAFE, BD BARD, BOSTON SCIENTIFIC, CSI – FRONTIER, INTACT VASCULAR, ABBOTT, MEDTRONIC, MICRO MEDICAL SOLUTIONS, PLURISTEM, LTD SURMODICS, VERYAN, VESPER MEDICAL: Consultant (Ongoing), Speaking and Teaching (Ongoing); Baylis Medical Technologies: Speaking and Teaching (Ongoing); CARDIOVASCUAR SYSTEMS (CSI), CORDIS/CARDINAL HEALTH, INARI MEDICAL INC., INTACT VASCULAR, MEDTRONIC, PHILIPS, VESPER: Consultant (Ongoing); Merit Medical: Contracted Research (Ongoing); phillips/volcano/Spectranetics: Speaking and Teaching (Ongoing); Terumo: Speaking and Teaching (Ongoing)

Learning Objectives:

Describe how to utilize hybrid Angiography-CT for localizing obscure GI bleeds not detected on CTA or angiography.

Describe the technical aspects and contrast infusion protocols of the procedure.

Present case-based clinical applications illustrating its utility in guiding treatment.

Background:

Lower gastrointestinal (GI) bleeding accounts for roughly 20-25% of all GI bleeds and occurs at an incidence of 33-87/100,000 people. The current diagnostic guidelines vary amongst different societies, but traditionally endoscopy was considered first line for evaluation {1}. In recent years, CT angiography has gained popularity for the evaluation of suspected acute GI bleeding with a sensitivity of 50-86%. For accurate diagnosis, CTA requires an active bleeding rate of at least 0.3-0.5ml/min {2,3,4}. CTA is more sensitive than conventional angiography at detecting active extravasation {5}. For this reason, angiography is typically reserved for patients with positive CTA findings with the intention to treat endovascularly. In situations where the bleed is slow and/or intermittent, endoscopic and CT angiography evaluation can be unrevealing. In these cases, referred to as obscure GI bleeding, next diagnostic steps are variable and could include repeat endoscopy, tagged RBC scan, capsule endoscopy, triple phase enterography, or provocative angiography. With the advent of hybrid angiography-CT (angio-CT), interventional radiologists are now able to perform high-resolution sub-selective mesenteric CTAs, with greater sensitivity than standard CTA, to aid in the diagnosis and treatment of obscure GI bleeds.

Clinical Findings/Procedure Details:

This educational exhibit will discuss current techniques for the utilization of angio-CT to aid in the identification and localization of obscure GI bleeds and outline our institutional protocols for image acquisition and contrast infusion. We will present multiple cases of slow persistent GI bleeding where hemorrhage was not visualized on CTA and/or angiography and only demonstrated with hybrid angio-CT, allowing effective treatment. Each case will emphasize specific learning points either pertaining to angio-CT technique or its utility in guiding endovascular treatment or alternative therapies. Some examples include:

Provocative angio-CT with intra-mesenteric tPA administration

Bowel “tagging” to guide surgical resection

Considerations for transcatheter arterial embolization of mesenteric arteries

Conclusion and/or Teaching Points:

Hybrid Angiography-CT is an emerging modality that has clinical utility in both the localization and treatment of obscure GI bleeds.