The Effect of Per-Oral Endoscopic Myotomy by Achalasia Subtype As Measured by Impedance Planimetry

Achalasia is an esophageal motility disorder with three subtypes based on manometry that can treated with per-oral endoscopic myotomy (POEM). With the advent of impedance planimetry (EndoFLIP®), we hypothesized the three achalasia subtypes would have different pre-POEM EndoFLIP® diameter and distensibility index (DI) measurements but would be similar after POEM. A single-institution, retrospective review of consecutive POEM cases by a single surgeon-endoscopist team from 04/07/2017 to 08/28/2023. Patients with a diagnosis of achalasia were stratified into type 1, 2, or 3 based on pre-POEM manometry. Patient characteristics, Eckardt scores, and pre-and-post-POEM diameter and DI were compared by subtype with descriptive, univariate, and multivariable linear regression statistics. Sixty-four patients met inclusion criteria, of whom 9(14.1