Comparative study of endoscopic clips: duration of attachment at the site of clip application

BACKGROUND: Several designs of endoscopic clips are now commercially available, and the indications for endoclip application are rapidly expanding. However, very limited data have been published to aid in choosing between the different types of endoclips. OBJECTIVE: To compare the duration of clip attachment between all commercially available endoclips. SETTING: Long-term experiments on 50-kg pigs under general anesthesia. DESIGN AND INTERVENTIONS: Upper endoscope was inserted into the stomach. One clip of each type (Resolution clip, TriClip, and HX-5L clip) was placed along the same gastric fold at a distance of 0.5 to 1 cm from each other. The animals were recovered. In pig nos. 1 and 2, repeat endoscopy was performed after 2 and 4 weeks. In pig nos. 3 to 5, endoscopy was repeated after 1, 2, and 5 weeks. MAIN OUTCOME MEASUREMENTS: Duration of clip retention at the site of application. RESULTS: In all animals, only the Resolution endoclip remained attached to the site of application for the entire duration of the study (4-5 weeks). No TriClips or HX-5L clips were attached at the 4- to 5-week follow-up endoscopies. Most of the TriClips (67%) detached within the first week after application. Most of the HX-5L clips (80%) dislodged within the first 2 weeks of follow-up. LIMITATIONS: The study was performed in a porcine model with a small number of animals. CONCLUSIONS: The Resolution clip has the longest duration of retention at the site of application (more than 4-5 weeks) and should be preferred when long-term attachment of endoclips is necessary.