In experienced hands, emergency endoscopic treatment with over-the-scope clips gives better outcomes than standard treatment in patients with high non-varicose gastrointestinal (GI) bleeding and a high risk of rebleeding. This was found in the STING-2 study from Germany. dr. Thijs Schwartz (Meander Medical Center) has a lot of experience with clipping and will use the over-the-scope clips more often as a result of this study, but does not expect this to apply to MDL doctors who have little experience with these clips. .
Image: Joris Aben Photography
Acute non-varicose high GI bleeding is a common clinical challenge with an estimated annual incidence of 40-150 cases per 100,000 in Europe and the United States. These bleedings have a death risk of up to 10%, especially in the elderly and patients with comorbidity.
Treatment with over-the-scope clips
Endoscopic hemostasis by submucosal injection (diluted epinephrine) combined with hemoclips or thermal therapy (coagulation) is a successful standard of first choice treatment (in 90% of bleeds). However, ‘rebleeding’ results in a smaller chance of successful endoscopic retreatment (75%). In addition, rebleeding is associated with an increased risk of death. If angiographic or surgical rescue therapy is required, the risk of death increases by 10-29%.
Over-the-scope clips were initially developed for closing GI perforations and fistulas, but are increasingly being used to treat GI bleeding. Several retrospective studies have shown that these clips are highly effective in achieving hemostasis in patients with severe (Forrest Ia/Ib/IIa/IIb; hemoglobin < 4,3 mmol/l) of hoogrisico (Rockall-score van > 7) high GI bleeding. For recurrent bleeding from gastric ulcers, the use of over-the-scope clips appears to be superior to standard endoscopic treatment. Studies indicate that these clips may also be effective for the first-line treatment of high-risk patients. Until now, there was little data on the first-choice treatment with over-the-scope clips. In addition, the exact indications for use of these clips have not yet been established.
Previous STING-1 study
In the previous STING-1 study, treatment with over-the-scope clips was found to be more effective than standard treatment in patients with recurrent bleeding ulcers. In addition, this treatment was associated with high success rates for major bleeding. Therefore, it is proposed as the primary treatment for high-risk patients.
However, apart from a recent small randomized controlled trial, the data are mainly limited to retrospective studies with heterogeneous study populations and inconsistent definitions of high-risk lesions.
Higher conversion rate
In the prospective, randomized, controlled, multicenter STING-2 study, the first choice of treatment with over-the-scope clips was compared with standard of care in patients with endoscopic evidence of acute high GI bleeding and a high risk of rebleeding, defined as full Rockall score of 7 or higher.
100 patients (mean age 78 years; 70% male) were randomly divided into two groups, receiving either over-the-scope clips or standard endoscopy. All but one patient in the standard group were treated with conventional clips. The standard therapy used in this study is different from his own practice, Schwartz said. “We do it more like the Americans, just like most Dutch clinics. Our standard treatment is injection therapy, usually with adrenaline, in combination with thermal coagulation. In this German study, both groups received injection therapy combined with either the over-the-scope clips or regular endoclips in the control group.”
The clinical success rate, defined as successful endoscopic hemostasis with no evidence of rebleeding, occurred in 91.7% of patients in the over-the-scope clips group and 73.1% in the standard group (p = 0.019) . The researchers chose this combined endpoint, as immediate and sustained hemostasis is the key outcome for these patients. This is also in line with international recommendations for high GI bleeding studies.
Persistent bleeding and trend for less rebleeding
Sustained bleeding did not occur in any patient in the over-the-scope clips group and in 6 patients in the standard group (p = 0.027). These 6 patients were all successfully treated with rescue therapy. Recurrent bleeding was observed in 4 patients (8.3%) in the over-the-scope clips group and in 8 patients (15.4%) in the standard group (p = 0.362).
Furthermore, a trend for the superiority of over-the-scope clips at day 30 was found. Due to 2 late rebleeds in that group (on days 10 and 14), the difference did not reach statistical significance (p = 0.084). This may be due to the small study size. All 6 patients with persistent bleeding and 5 of 8 patients with recurrent bleeding after standard endoscopy were successfully treated with over-the-scope clips.
Employed, but experience required
Consistent with the STING-1 study, these results demonstrate the efficacy of over-the-scope clips for difficult sources of bleeding and endoscopic rescue therapy after failure of standard methods.
All endoscopists participating in the STING-2 study were highly experienced in the application of over-the-scope clips. In their clinical experience, there is certainly a learning curve for the application of these and associated accessories, especially for addressing large lesions or lesions located in difficult locations. “You have to do at least 20 of these interventions,” Schwartz adds. “That is quite a difficult point, because you do not get enough experience with the number of bleeding you encounter each year. Therefore, you will have to gain experience with this clip in other ways. That is especially with an endoscopic full-thickness resection.” Schwartz therefore has some experience with the over-the-scope clip: “We now have a device that uses the same technology as the over-the-scope clip, called a full-thickness resection device (FTRD). A loop is built into that device to excise, for example, an early carcinoma with intestinal wall and all. The resulting defect is closed in the same session with the over-the-scope clip. MDL doctors who have experience with full-thickness resection devices also have experience with such an over-the-scope clip. As a result, more and more colleagues are also familiar with these clips, although most MDL doctors will have no experience with them.”
Not a real practice changer
The researchers believe that the intervention with over-the-scope clips should be considered for selected patients with high GI bleeding and at high risk of rebleeding.
So Schwartz wonders whether this study is a real ‘practice changer’, given the need for sufficient experience with the technique, but does think that the over-the-scope clips are a useful addition to the current therapy. “Especially if it concerns an ulcer, which can be closed with a clip, which does not apply to every bleeding or bleeding ulcer.” He considers the latter to be a weak point of this article. “There is a considerable selection bias. The cases were selected based on the opinion of the endoscopist whether the patient in question was eligible for treatment with an over-the-scope clip. That is not always the case. Sometimes it is very difficult to clip a bleeding ulcer, for example because it is very fibrotic or because it is at an awkward angle. Those patients were not included in this study. However, if I now find a suitable patient, I will now clip with the over-the-scope clip rather than with a regular endoclip.”
Follow-up research
Further research is needed to evaluate the possibility of wider use of this more complex and expensive hemostatic treatment and to identify which subgroups benefit most from hemostasis with over-the-scope clips.