G-POEM safe, effective for refractory gastroparesis

A recent study has demonstrated the safety and efficacy of gastric per-oral endoscopic myotomy, or G-POEM, in the treatment of patients with refractory gastroparesis.

"G-POEM is a technically feasible and likely effective treatment strategy, regardless of symptom predominance or aetiology,” the investigators said. 

“Validated measures, including gastroparesis cardinal symptom index (GCSI), rate of gastric emptying, and impedance planimetry, universally improve following pyloromyotomy,” they added.

Following the PRISMA and MOOSE guidelines, the investigators developed individualized search strategies for this systematic review and meta-analysis through February 2021. They then calculated pooled proportions and mean differences pre- and postprocedure and estimated rates using random effects models.

Outcomes measured were as follows: technical success, clinical success, improvement in GCSI, change in gastric emptying rate, alterations in impedance planimetry (functional lumen imaging probe [FLIP]) assessment, and adverse events (AEs).

Twenty studies, including a total of 797 patients (mean age 48.92 years, 67.41 percent female), met the eligibility criteria. Participants had an average duration of 4.24 years since gastroparesis diagnosis. [J Clin Gastroenterol 2025;59:325-334]

The rate of technical success was 98.47 percent (95 percent confidence interval [CI], 97.14–99.19; I2, 0.00), with a mean myotomy length of 3.78 cm. G-POEM also achieved clinical success, with a mean preprocedure GCSI of 3.38, significantly improving postprocedure (weighted mean difference, –1.56, 95 percent CI, –1.89 to –1.24; I2, 82.53; p<0.001).

Gastric retention after 4 h improved by nearly 50 percent (preprocedure 43.08 percent vs postprocedure 22.97 percent; p<0.001). In addition, FLIP assessment with 40- and 50-mL balloons showed a significant increase in diameter, distensibility index, and cross-sectional area postprocedure (p<0.05 for all).

With regard to safety, AEs related to the procedure were reported in 10.92 percent (95 percent CI, 5.09–19.32; I2, 82.85) of patients. Many of these AEs were also mild.

“While long-term data are still lacking, objective measures of clinical success support the notion that G-POEM is a viable treatment option for patients with gastroparesis refractory to medical therapy,” the investigators said. “Larger studies will serve to reduce heterogeneity and estimation uncertainty moving forward." 

Impedance planimetry

Notably, G-POEM may not be beneficial to all patients with gastroparesis, particularly those with no evidence of pyloric dysfunction.

An earlier study has examined impedance planimetry at the pylorus in gastroparesis, despite being validated at the lower esophageal sphincter, in which pyloric sphincter diameter and cross-sectional area showed an inverse relationship with early satiety and postprandial fullness. [Neurogastroenterol Motil 2015;27:524-531] 

“In addition, a notable benefit of utilizing FLIP as compared with alternative measures such as symptom scales (ie, GCSI) or 4-hour gastric emptying scintigraphy is the availability of immediate feedback on the adequacy of the myotomy,” the investigators said. “As such, we strongly recommend the routine use of impedance planimetry prior to and during pyloromyotomy.”

Gastroparesis is characterized by symptoms similar to dyspepsia, along with physiologic disturbances in antral hypomotility, increased gastric outlet resistance, and pyloric dysfunction with no evidence of obstruction. [Curr Treat Options Gastroenterol 2007;10:283–293; Gastroenterology 2004;127:1592-1622; Am J Gastroenterol 2013;108:18-37]