Clinical Outcomes and Predictors of Early Adverse Events in Primary EUS-Guided Choledochoduodenostomy for Malignant Distal Biliary Obstruction

Endoscopic ultrasound-guided biliary drainage (EUS-BD) is an alternative for failed endoscopic retrograde cholangiopancreatography, with increasing reports of its use as primary drainage. We have performed primary EUS-guided choledochoduodenostomy (EUS-CDS) since 2010, continuously improving techniques for safety. This study evaluated factors influencing early adverse events. Of 306 consecutive patients in whom EUS-CDS was attempted between September 2003 and February 2025, we conducted a retrospective study of 190 in whom primary EUS-CDS was attempted using a covered self-expandable metal stent for malignant distal biliary obstruction. EUS-CDS was deemed unsuitable in 26 of 190 cases (13.7%) due to ascites or tumor invasion, and the procedure was aborted without puncture. Among eligible cases, the technical and clinical success rates were 97.0% (159/164) and 97.5% (155/159), respectively. Early adverse events occurred in 4.9% (8/164), including acute cholangitis/peritonitis/mucosal double penetration/acute cholecystitis/bleeding (3/2/2/2/2) (overlap) with one severe case. Multivariate analysis identified scope type (OR: 5.153, 95% CI: 1.15–22.92, p = 0.031) as an independent risk factor for early adverse events. Primary EUS-CDS demonstrated high technical and clinical success rates with a low early adverse event rate. Scope type was an independent risk factor. Proper patient selection and device modifications can enhance the safety and feasibility of primary EUS-CDS.