BACKGROUND
Transarterial embolization (TAE) for acute lower gastrointestinal bleeding (LGIB) can be technically challenging due to the compromise between achieving hemostasis and causing tissue ischemia. The goal of the present study is to determine its technical success, rebleeding, and post-embolization ischemia rates through meta-analysis of published literature in the last twenty-years.
MATERIALS AND METHODS
PubMed, Embase, and Cochrane Library databases were queried. Technical success, rebleeding, and ischemia rates were extracted. Baseline characteristics such as author, publication year, region, study design, embolization material, percentage of superselective embolization were retrieved. Subgroup analysis was performed based on publication time and embolization agent.
RESULTS
A total of 66 studies including 2121 patients who underwent embolization for acute LGIB were included. Endoscopic management was attempted in 34.5%. The pooled overall technical success, rebleeding, post-embolization ischemia rates were 97.0%, 20.7%, and 7.5%, respectively. Studies published after 2010 showed higher technical success rates (97.8% vs 95.2%), lower rebleeding rates (18.6% vs 23.4%), and lower ischemia rates (7.3% vs 9.7%). Compared to microcoils, NBCA was associated with a lower rebleeding rate (9.3% vs 20.8%) at the expense of a higher post-embolization ischemia rate (9.7% vs 4.0%). Coagulopathy (p = 0.034), inotropic use (p = 0.040), and malignancy (p = 0.002) were predictors of post-embolization rebleeding; hemorrhagic shock (p < 0.001), inotropic use (p = 0.026), malignancy (p < 0.001), coagulopathy (p = 0.002), blood transfusion (p < 0.001), and enteritis (p = 0.023) were predictors of mortality. Empiric embolization achieved a similarly durable hemostasis rate to targeted embolization (23.6% vs 21.1%) but a higher risk of post-embolization ischemia (14.3% vs 4.7%).
CONCLUSION
For LGIB, TAE has a favorable technical success rate and low risk of post-embolization ischemia. Its safety and efficacy profile has increased over the last decade. Compared to microcoils, NBCA seemed to offer a more durable hemostasis rate at the expense of higher ischemia risk. Due to the heterogeneity of currently available evidence, future prospective and comparative studies are warranted.