Predictive factors for extraction of common bile duct stones during endoscopic retrograde cholangiopancreatography in Billroth II anatomy patients.

Background: Endoscopic retrograde cholangiopancreatography (ERCP) for extraction of common bile duct (CBD) stones in Billroth II anatomy patients is still a technical challenge and factors affecting stone extraction have not yet been clarified. This study aimed to analyze our experience and evaluate potential factors affecting CBD stone extraction.
Methods: A retrospective analysis of CBD stones patients with a history of Billroth II gastrectomy, who underwent therapeutic ERCP for stone extraction at our center from August 1999 to December 2017, was conducted. The outcomes of ERCP and potential factors affecting stone extraction were examined.
Results: A total of 227 patients were enrolled, and 176 patients (77.5%) achieved technical success. The success rate of duodenal ampullary access and selective biliary cannulation was 84.1% (191/227) and 92.1% (176/191), respectively. The mean CBD diameter was 15 mm (range 6-35 mm), and the largest stone size was 13 mm (range 4-36 mm). CBD stones were ultimately removed in 137 patients (77.8%), and 105 patients (59.7%) for the first session. Mechanical lithotripsy was used in 17 patients (9.7%). The overall ERCP-related complication rate was 6.3% (11/176), including bleeding in 3 patients (1.7%) and mild pancreatitis in 6 patients (3.4%). The multivariate analysis indicated that CBD stone number ≥ 2 (OR 2.171; 95% CI 1.095-4.306; p = 0.027), and the largest CBD stone size ≥ 12 mm (OR 3.646; 95% CI 1.833-7.251; p < 0.001) were patient-related risk factors for failed stone removal; while the use of endoscopic papillary (large) balloon dilation (EPBD/EPLBD) (OR 0.291; 95% CI 0.147-0.576; p < 0.001) was a procedure-related protective factor for successful stone extraction.
Conclusions: ERCP is safe and effective for extraction of CBD stones in Billroth II anatomy patients. The number and the largest size of CBD stones, and the use of EPBD/EPLBD are predictive factors for CBD stone extraction.