Background and study aims We aimed to identify risk factors and salvage technique for technical failures of endoscopic ultrasound-guided choledochoduodenostomy (EUS-CDS) and evaluate the short and long-term consequences in patients with biliary obstruction. Patients and methods This retrospective multicenter study included EUS-CDS from 2018 to 2024. Cases were defined as technical failure and classified as follow: type1 (digestive-flange mispositioned), type2 (biliary-flange mispositioned), type3 (stent deployment failure), type4 (catheter-LAMS through the bile duct), and type5 (others). Controls were successful EUS-CDS in the same center and period. The primary endpoint was to to identify risk factors for failure. Secondary endpoints were to describe the endoscopic rescue techniques to evaluate immediate and long-term consequences. Results Technical failures occurred in 7% (95%CI[5
9]). In 23 centers, 296 patients were included (53% male, 71±16 years): 100 cases (type1 [26%], type2 [41%], type3 [11%], type4 [6%], and type5 [16%]) and 196 controls. Risk factors in multivariate analysis for technical failures included CBD diameter ≤15mm, duodenal stenosis, Wired technique and low operator experience (≤10 LAMS). Endoscopic salvage was successful in 77% of cases, with 53% using a covered metal stent and 22% using a new LAMS. Early failures were mild in 50% of cases, but 12% resulted in death within 30 days. Immediate endoscopic salvage reduced severe clinical adverse event (p<
0.00001) and increased success rates (p<
0.0004). Conclusions EUS-CDS failures are not rare and are severe in half of the cases. Recognizing risk factors, identifying failures during the procedure, and knowing endoscopic salvage methods are crucial.