Clinical efficacy of anti-migration features in fully covered metallic stents for anastomotic biliary strictures after liver transplantation: comparison of conventional and anti-migration stents.

BACKGROUND AND AIMS: Anastomotic biliary strictures (ABSs) are one of the most frequent adverse events that occur after orthotopic liver transplantation (OLT). Multiple plastic stents (MPS) have been validated for this indication. More recently, fully covered self-expandable metallic stents (FCSEMSs) have been used with positive outcomes, but also have a higher rate of migration, which may limit success. Our primary objective was to compare stent migration rates observed with standard FCSEMSs (Std-FCSEMSs) and so-called anti-migration FCSEMSs (Am-FCSEMSs), which are newly designed with reversed proximal side flaps. Secondary objectives were to compare rates of stricture resolution and procedure-related morbidity.

METHODS: We conducted a retrospective analysis of a subset of patients (FCSEMSs for post-OLT ABS) from 2 prospectively maintained databases of (1) OLT patients, and (2) ERCP and stent placement. Between January 2009 and January 2016, consecutive patients presenting with ABS after OLT referred to Cochin Hospital (Paris, France) for ERCP and receiving a FCSEMS were included. Exclusion criteria were any other cause of biliary stricture (ie, malignant stricture, ischemic origin), and biliary fistulae.

RESULTS: One hundred twenty-five FCSEMSs (57 Am-FCSEMSs, 52 type 1 Std-FCSEMSs, and 16 type 2 Std-FCSEMSs) were used in 75 patients for ABS after OLT, with a planned stent placement period of 6 months in all patients. Patient characteristics and rates of previous endoscopic treatment or timing of ABS occurrence after OLT were not different between the groups. The rate of FCSEMS complete migration was 16% (20/125), consisting of 1.7% (1/57) for Am-FCSEMSs and 28% (19/68) for type 1 and 2 Std-FCSEMSs (P < .0001). All attempted stent removals (100% of patients) were successful. First follow-up ERCP after each FCSEMS highlighted a stricture resolution rate of 78.4% (98/125), including 93% (53/57) for Am-FCSEMSs and 66.2% (45/68) for type 1 and 2 Std-FCSEMSs (P < .001). After a median follow-up of 28 months after stent removal (range, 12-66 months), stricture recurrence was observed in 12.3% (range, 11%-17%) of patients treated with Am-FCSEMSs against 55.9% (range, 54%-56%) of those receiving Std-FCSEMSs (P < .0001).

CONCLUSIONS: In patients with ABS after OLT, the use of Am-FCSEMSs significantly decreased the risk of stent migration, improved stricture resolution at the time of stent removal, and reduced the rate of stricture recurrence during follow-up. Endoscopic removal success and procedure-related morbidity were similar for both standard and anti-migration stents.