Background
To investigate factors associated with risk for rebleeding and 30-day mortality following prophylactic transarterial embolization in patients with high-risk peptic ulcer bleeding.

Methods
We retrospectively reviewed medical records and included all patients who had undergone prophylactic embolization of the gastroduodenal artery at Rigshospitalet, Denmark, following an endoscopy-verified and treated peptic Sulcer bleeding, from 2016 to 2021. Data were collected from electronic health records and imaging from the embolization procedures. Primary outcomes were rebleeding and 30-day mortality. We performed logistical regression analyses for both outcomes with possible risk factors. Risk factors included: active bleeding; visible hemoclips; Rockall-score; anatomical variants; standardized embolization procedure; and number of endoscopies prior to embolization.

Results
We included 176 patients. Rebleeding occurred in 25% following embolization and 30-day mortality was 15%. Not undergoing a standardized embolization procedure increased the odds of both rebleeding (odds ratio 3.029, 95% confidence interval (CI) 1.395–6.579) and 30-day overall mortality by 3.262 (1.252–8.497). More than one endoscopy was associated with increased odds of rebleeding (odds ratio 2.369, 95% CI 1.088–5.158). High Rockall-score increased the odds of 30-day mortality (odds ratio 2.587, 95% CI 1.243–5.386). Active bleeding, visible hemoclips, and anatomical variants did not affect risk of rebleeding or 30-day mortality. Reasons for deviation from standard embolization procedure were anatomical variations, targeted treatment without embolizing the gastroduodenal artery, and technical failure.

Conclusions
Deviation from the standard embolization procedure increased the risk of rebleeding and 30-day mortality, more than one endoscopy prior to embolization was associated with higher odds of rebleeding, and a high Rockall-score increased the risk of 30-day mortality. We suggest that patients with these risk factors are monitored closely following embolization. Early detection of rebleeding may allow for proper and early re-intervention.