667 GASTRIC PERORAL ENDOSCOPIC MYOTOMY (G-POEM) FOR THE TREATMENT OF REFRACTORY GASTROPARESIS: FINAL RESULTS FROM THE FIRST INTERNATIONAL PROSPECTIVE TRIAL

Abstract

We previously reported the preliminary short-term outcomes of our prospective trial on gastric per-oral endoscopic myotomy (G-POEM) with promising results. To prospectively 1) evaluate the efficacy and safety of G-POEM and 2) assess factors associated with clinical success of G-POEM. In this prospective multicenter (4 US, 1 South America) study, patients with refractory gastroparesis - defined as symptoms refractory to standard medical therapy - underwent G-POEM between 11/2015 and 11/2018, and were followed for one year. Clinical symptoms (measured by Gastroparesis Cardinal Symptom Index [GCSI]) and quality of life (measured by Short Form 36 [SF-36]) were evaluated before and at 1-, 3-, 6-, and 12-month followups. Clinical success was defined as one score decrease in average GCSI with >25% decrease in at least 2 sub-scales. Gastric emptying study (GES) was performed before and 3 months after the G-POEM. Pylorus characteristics were measured by endoscopic functional luminal imaging probe (EndoFLIP) device pre and post G-POEM. A total of 80 patients (F 71%, mean age: 49yr) were enrolled. The most common etiology was idiopathic (41.3%), followed by postsurgical (35%) and diabetes (23.8%). All procedures were technically successful (technical success 100%). A total of 67 (84%) patients were followed up to one year with clinical success rate of 59.7%. GCSI and its subscales improved significantly following G-POEM (p<0.05) (Figure 1). Furthermore, 5 out of 8 domains of SF-36 including physical functioning, physical role, energy, emotional well-being, social functioning, general health, and health change improved significantly after G-POEM (p<0.05). A total of 5 adverse events, all rated as mild, were reported and included 3 symptomatic capnoperitoneum (treated by needle decompression), 1 mucosotomy (treated with stent replacement), and 1 thermal mucosal injury (treated with clipping). Pre and 3-month post G-POEM GES were performed in 53 (66.3%) patients. GES improvement and normalization were achieved in 34/53 (64.2%) and 25/53 (47.2%) patients, respectively. Following G-POEM, pylorus distensibility index (DI), measured with EndoFLIP, increased from 4.99 ± 2.57 to 6.74 ± 4.34 mm2/mmHg, and from 4.97 ± 3.02 to 6.99 ± 3.92 mm2/mmHg using 40- and 50-ml volume bags, respectively (p<0.05). Lower pre G-POEM DI using 40 ml bag was significantly associated with pre G-POEM disease severity (p=0.039). Baseline disease severity and increase in pylorus DI following G-POEM were significantly associated with clinical success (Table 1). G-POEM is safe and improves clinical symptoms and pylorus characteristics of patients with refractory gastroparesis. Disease severity predicts the one-year clinical success; thus, the procedure may be considered for patients with more severe gastroparesis symptoms.Table 1association between disease characteristics and one-year clinical success of G-POEMView Large Image Figure ViewerDownload Hi-res image Download (PPT)