Capsule Endoscopy or Angiography in Patients With Acute Overt Obscure Gastrointestinal Bleeding

A Prospective Randomized Study With Long-Term Follow-Up

Wai K Leung MD; FACG; Simon S M Ho MBBS; Bing-Yee Suen BN; Larry H Lai MBChB; Simon Yu MD; Enders K W Ng MD; Simon S M Ng MD; Philip W Y Chiu MD; Joseph J Y Sung MD; PhD; Francis K L Chan MD; James Y W Lau MD


Am J Gastroenterol. 2012;107(9):1370-1376. 

In This Article

Abstract and Introduction


Objectives: Both capsule endoscopy (CE) and angiography have been recommended as first investigation for patients with acute overt obscure gastrointestinal bleeding (OGIB). However, no studies have directly compared the two modalities in patients with overt OGIB. We compared the diagnostic yield and long-term outcomes of patients with overt OGIB randomized to CE or angiogram.

Methods: Consecutive patients presented with acute melena or hematochezia, but nondiagnostic upper and lower endoscopy, were immediately randomized to receive small-bowel CE or angiography. All patients were monitored for rebleeding and anemia for up to 5 years. Primary end point was the diagnostic yield of the assigned investigation. Secondary end points included rebleeding, further transfusion, readmission for bleeding or anemia, and mortality.

Results: A total of 60 patients with overt OGIB were randomized. The mean follow-up was 48.5 months. The diagnostic yield of immediate CE was significantly higher than angiography (53.3% vs. 20.0%, P=0.016). The cumulative risk of rebleeding in the angiography and CE group was 33.3% and 16.7%, respectively (P=0.10, log-rank test). There was no significant difference in the long-term outcomes between the two groups including further transfusion, hospitalization for rebleeding, and mortality.

Conclusions: In patients with overt OGIB, immediate CE has higher diagnostic yield and comparable long-term outcomes when compared with angiography.


Obscure gastrointestinal bleeding (OGIB) is defined as bleeding of unknown origin that persists or recurs after an initial negative endoscopic evaluation including upper endoscopy and colonoscopy.[1,2] OGIB can be further divided into overt or occult bleeding depending on the presence of visible bleeding or not. OGIB is not uncommon and could account for 7–8% of patients presenting with melena or hematochezia.[3]

The availability of small-bowel capsule endoscopy (CE), which enables direct and complete visualization of small-bowel mucosa, has revolutionized the approach to OGIB. Some initial trials suggest that CE might be more sensitive than other techniques such as push enteroscopy, small-bowel series, or computed tomography (CT) enterography.[4–9]

For patients with active overt GIB after negative upper endoscopy and colonoscopy, most current guidelines recommended CE to be the investigation of choice.[1,2,10] However, for patients with massive bleeding, endoscopy with therapeutic capability or referral for angiography are recommended.[2] In particular, patients with massive bleeding are recommended to undergo angiography.[1,2] Nonetheless, massive bleeding is less frequent than overt OGIB. The current guidelines are based on limited data and there is no prospective randomized study directly comparing angiography with CE in the setting of acute bleeding. Hence, the exact positioning of these two investigations for overt OGIB remains elusive. In a small, nonrandomized study,[11] CE detects more lesions than CT or standard angiography in patients with OGIB. However, all patients received angiography before CE and the real clinical impact of CE in patients with active OGIB remains undetermined. Furthermore, very few randomized trials actually recruit patients with active bleeding.

In this study, we prospectively randomized patients with active overt OGIB to receive either immediate CE or angiography. We compared the diagnostic yield as well as the long-term clinical outcomes of patients with overt OGIB randomized to CE or angiography.