Background:Gastric outlet obstruction (GOO) of the excluded (remnant) stomach is a rare complication after Roux-en-Y gastric bypass (RYGB), typically related to chronic accumulation of secretions or mechanical narrowing. Because the remnant stomach is inaccessible by standard endoscopy, diagnosis and management can be challenging. We describe the diagnostic and therapeutic utility of endoscopic ultrasound (EUS)–guided decompression using a lumen-apposing metal stent (LAMS) for excluded-stomach GOO (eGOO).

Case Description:A 63-year-old woman with prior RYGB presented with progressive epigastric fullness, postprandial nausea, and abdominal pain. CT imaging demonstrated marked distension of the excluded stomach with features consistent with GOO and non-specific eccentric thickening of the gastric antrum.

Esophagogastroduodenoscopy was unremarkable due to the altered anatomy. EUS, however, revealed a markedly distended remnant stomach with diffuse antral wall thickening. Given these findings, EUS-directed gastric decompression was pursued.

A cautery-enhanced 15 × 10 mm LAMS was then deployed to create a jejuno-gastrostomy between the jejunal limb and the remnant stomach. A slim endoscope was advanced through the LAMS, revealing over 1.5 liters of retained fluid, pyloric stenosis, and significant duodenal bulb ulceration. Biopsies demonstrated benign peptic ulcer disease and were negative for H. pylori.

The patient experienced prompt improvement in upper-GI symptoms. Follow-up EGD/EUS demonstrated resolution of obstruction, and cross-sectional imaging at 12 months confirmed no evidence of neoplasia or complications. The patient later elected to undergo remnant gastrectomy to futher exclude malignancy, which was performed without difficulty, indicating that prior LAMS access did not preclude surgical management. Final pathology was benign pyloric stenosis.

Conclusion:This case highlights the value of therapeutic EUS as an effective minimally invasive strategy for both diagnosing and treating eGOO using a LAMS. The approach provides rapid symptom relief, enables same-session evaluation of the remnant stomach and duodenum, and importantly, does not hinder subsequent surgical gastrectomy when clinically indicated.