Pilot study of a novel lumen-apposing metal stent for endoscopic ultrasound-guided procedures in porcine models

Abstract

Lumen-apposing metal stents have expanded the therapeutic potential of interventional endoscopic ultrasound (EUS). The Hot-Spaxus (Taewoong Medical Co., Ltd.), the second most commonly utilized lumen-apposing metal stent, requires two operators for its release which has been considered a limitation compared to other lumen-apposing metal stents. We aimed to test the feasibility and the technical success of a newly available version of the Hot-Spaxus stent equipped with an innovative handle delivery system for EUS-guided interventional procedures. We conducted a pilot study using porcine models. The novel Hot-Spaxus 2 was tested by performing four EUS-guided procedures including four EUS-guided gallbladder drainage and 12 EUS-guided gastrojejunostomy) procedures. Technical success was reported in 100% of cases. The mean procedure time for EUS-guided gatrojejunostomyJ and EUS-guided gallbladder drainage was 23.85 min (standard deviation 3.41) and 16.15 min (standard deviation 2.72), respectively. The distal and proximal flanges were safely released by the endosonographer without any complications. No adverse events were reported. In conclusion, the novel Hot-Spaxus 2 stent may represent an improvement compared to the prior Spaxus model. Unlike its predecessor, this newly designed stent eliminates the need for two endoscopists and can be deployed by a single operator. Further human studies are necessary to validate its clinical effectiveness.

Keywords: EUS‐GBD; EUS‐GE; Hot‐Spaxus; endoscopic ultrasound; lumen‐apposing metal stents.

FIGURE 1

(a) Graphical description of Hot Spaxus 2 Handle. (b) Hot Spaxus 2 HandleGraphical description of the new Hot Spaxus Handle of the new Hot‐Spaxus 2 handle (one plug for connecting the electrosurgical unit, two main catheter control, three pins indicating half deployment markers, four stent deployment grip, five stent deployment grip controls, six main catheter control locks, seven luer lock covers, luer lock case, nine Hot‐Spaxus stent preloaded, and 10 holes for guide‐wire).

FIGURE 2

Graphic representation of steps involved in stent preparation and deployment Graphic representation of steps involved in stent preparation and deployment Graphic representation of handle. (a) Align the handle with the endoscope and attach it by rotating the luer lock fitting clockwise while keeping the handle stationary and aligned with the endoscope. (b) Push the main catheter lock to the right to unlock the catheter and to the left to relock it. (c) With the main catheter control unlocked, carefully advance the main catheter control (in the direction indicated by the arrow) so that the distal end of the catheter moves towards the gastrointestinal (GI) tract adjacent to the target structure. (d) Catheter marker “A” is then advanced into the target organ. (e) Distal flange opening into appropriate positioning. The stent deployment grip instantly locks into position with a “click” sound, and it cannot be moved out from position. (f) Push the stent deployment grip lock to the right to unlock the stent deployment grip.

FIGURE 3

Stent releasing graphical display. (a) Retract the stent deployment grip to release the stent's first flange. (b) Pull the stent deployment grip all the way to deploy the proximal flare of the stent. (c) Deploy the stent deployment grip in the arrow direction points to the second flare of the stent. (d) The second flare is deployed and connects both walls together.