Per-oral endoscopic myotomy (POEM) results in improvement in an endoscopic score for achalasia (the CARS Score)

We recently developed the CARS score, an endoscopic scoring system for achalasia that is based on four common endoscopic findings of the disease (i.e., esophageal Contents, Anatomy, Resistance at the LES, and Stasis). We have shown that the CARS score performs well in predicting the presence of achalasia. Now, we aimed to find whether the CARS score improves after treatment of achalasia or EGJ outflow obstruction (EGJOO) with peroral endoscopic myotomy (POEM).

We reviewed our Center for Esophageal Diseases clinical database for patients who had POEM performed for treatment of achalasia or EGJ outflow obstruction between January 2020 and December 2022. Such patients underwent a comprehensive work up for their motility disorders including endoscopy with calculation of CARS score before and after POEM. Patients with suspected or known achalasia were instructed to be on a 1-5 day liquid diet prior to their endoscopic procedures.

Eighty nine patients treated with POEM meet inclusion criteria; 74 patients had achalasia (9 type 1, 46 type 2, 19 type 3), and 15 had EGJOO. The CARS score decreased significantly after POEM (3.5 vs 1.7, p < 0.01). Subset analyses of CARS subscores revealed significant reductions in contents (mean reduction 0.25, p < 0.05), resistance at the LES (mean reduction 1.3, p < 0.01) and stasis (mean reduction 0.3, p < 0.01). Patients with Type 1/2 achalasia had improvement in all CARS subscores whereas those with EGJOO/Type 3 achalasia had improvement primarily in LES resistance.

We found significant reductions in the endoscopic CARS score in patients treated with POEM. Reductions in total CARS scores were driven primarily by improvements in the endoscopic assessment of Contents, Resistance-LES and Stasis subscores. Improvement in CARS subscores appear to differ depending on HRM diagnosis. Further studies are needed to determine whether improvement in the CARS score.