Clinical efficacy of gastric per-oral endoscopic myotomy (G-POEM) in the treatment of refractory gastroparesis and predictors of outcomes: a systematic review and meta-analysis using surgical pyloroplasty as a comparator group.

[BACKGROUND AND AIMS] Gastric peroral endoscopic myotomy (G-POEM) is a novel minimally invasive technique in endosurgery. Data is limited as to its efficacy, safety, and predictive factors. We conducted this meta-analysis to evaluate the clinical outcomes of G-POEM and used the outcomes of surgical pyloroplasty as a comparator group in the treatment of refractory gastroparesis.

[METHODS] We searched multiple databases from inception through March 2019 to identify studies that reported on G-POEM and pyloroplasty in gastroparesis. Our primary outcome was to analyze and compare the pooled rates of clinical success, in terms of Gastroparesis Cardinal Symptom Index (GCSI) score and 4-h gastric emptying study (GES) results, with G-POEM and pyloroplasty.

[RESULTS] Three hundred and thirty-two and 375 patients underwent G-POEM (11 studies) and surgical pyloroplasty (seven studies), respectively. The pooled rate of clinical success, based on the GCSI score, with G-POEM was 75.8% (95% CI 68.1-82.1, I = 50) and with surgical pyloroplasty was 77.3% (95% CI 66.4-85.4, I = 0), with no significance, p = 0.81. The pooled rate of clinical success, based on the 4-hour GES results, with G-POEM was 85.1% (95% CI 68.9-93.7, I = 74) and with surgical pyloroplasty was 84% (95% CI 64.4-93.8, I = 81), with no significance, p = 0.91. The overall adverse events were comparable. Based on meta-regression analysis, idiopathic gastroparesis, prior treatment with botulinum toxin and gastric stimulator seemed to predict clinical success with G-POEM.

[CONCLUSION] G-POEM demonstrates clinical success in treating refractory gastroparesis. Idiopathic gastroparesis, prior treatment with botulinum injections and gastric stimulator appear to have positive predictive effects on the 4-h GES results after G-POEM. Outcomes seem comparable to surgical pyloroplasty.