Feasibility of biliary stenting to distal malignant biliary obstruction using a novel designed metal stent with duckbill‐shaped anti‐reflux valve

Abstract

Objectives: Anti-reflux metal stent (ARMS) has been used to prevent recurrent biliary obstruction (RBO) due to sludge formation or food impaction. However, the most suitable ARMS remains to be identified. This study aimed to evaluate the feasibility, safety, and efficacy of biliary drainage using duckbillshaped ARMS (D-ARMS).Methods: This was a multicenter, retrospective observational study conducted at three Japanese tertiary institutions. Patients with distal malignant biliary obstruction who underwent biliary stenting using D-ARMS were eligible to participate. Technical success, functional success, adverse event (AE), and time to RBO (TRBO) were evaluated.Results: Thirty patients underwent biliary stenting using D-ARMS from December 2018 to October 2019. The technical success rate and functional success rate were 93% and 87%, respectively. However, nonvisibility of the markers at the tip of the metal stent or spontaneous extension was occasionally observed, making biliary stenting using D-ARMS difficult. Early AE occurred in 10% of the patients including cholangitis and pancreatitis. During the median postprocedural observation time of 5.1 months (range, 0.8-22.8), RBO occurred in 33% and the median TRBO was 261 days. As for reintervention, D-ARMS could be extracted in 67% of the patients with RBO. However, the stent was torn off on removal in half of the patients.Conclusions: Although some modifications are still needed, D-ARMS was feasible and safe for biliary drainage, and sufficient TRBO was achieved. Subsequent multi-institutional studies involving a larger number of patients and a longer follow-up period are warranted to validate the present results.

A novel laser‐cut fully covered metal stent with anti‐reflux valve in patients with malignant distal biliary obstruction refractory to conventional covered metal stent

“…Previous reports of ARMS for distal MBO are summarized in Table 3 8–18 . All the previous ARMS were braided type SEMS and some of them were UMS or partially CMS.…”

“…Previous reports of ARMS for distal MBO are summarized in Table 3. [8][9][10][11][12][13][14][15][16][17][18] All the previous ARMS were braided type SEMS and some of them were UMS or partially CMS. The structure of ARV was extremely different in each ARMS.…”

“…Several types of anti‐reflux metal stents (ARMSs) have been introduced to overcome duodeno‐biliary reflux: hemispheric‐shaped, S‐shaped, wineglass‐shaped, nipple‐shaped, long funnel‐shaped, and windsock‐shaped ARMS 8–18 . All these previous ARMS are braided type SEMS.…”

“…Several types of anti-reflux metal stents (ARMSs) have been introduced to overcome duodeno-biliary reflux: hemispheric-shaped, S-shaped, wineglass-shaped, nippleshaped, long funnel-shaped, and windsock-shaped ARMS. [8][9][10][11][12][13][14][15][16][17][18] All these previous ARMS are braided type SEMS. Although ARMS was associated with a lower rate of stent occlusion compared to conventional SEMS in several studies, the results of these studies are inconsistent and the stent patency was not satisfactory enough.…”

Impact of sarcopenia on recurrent biliary obstruction after insertion of self‐expandable metallic stent in patients with malignant biliary obstruction

“…A recent study revealed a usefulness of anti-reflux metal stent to prevent RBO due to sludge or food impaction. 30 We may consider active use of the stent to prevent RBO in patients with sarcopenia. As the mechanisms and relationship between sarcopenia and RBO are not fully explained, further investigations with large numbers of patients are required.…”