Development and application of endoloops for the treatment of bleeding esophageal varices

Background: Endoloops are detachable nylon snares. The aims of this study w ere to develop an endoscopic method for repeated delivery of endoloops to a rrest variceal bleeding, to compare efficacy of endoloop hemostasis with in jection and band ligation in experimental models of bleeding, and to test t he reliability and safety of endoloops in a pilot study in patients with va rices. Methods: Technical modifications including ridged end-caps and alterations in angulation of endoloops were developed to speed delivery and improve eff icacy. Hemostatic efficacy of endoloops was compared with sclerotherapy and band ligation in animal studies before studies in: patients. Results: Modified endcap and endoloops allowed repeated applications withou t withdrawal of the endoscope. Right-angled endoloops ensnared more (p < 0. 0001) gastric tissue and were more reliable (p < 0.05) than straight:endolo ops, Injection therapy and pre-stretched bands appeared ineffective, wherea s band ligation was only effective on vessels up to 2 mm in diameter. Only endoloops achieved hemostasis on vessels of 3 to 5 mm (p < 0.05). No signif icant complications occurred using endoloops in animal (esophagus n = 20, s tomach n = 20) or human (n = 11) studies. Conclusions: Endcap and endoloop modifications simplified repeated applicat ion to varices. Endoloops were more effective than injection or band ligati on in experimental hemostasis and appeared safe and effective in patients.