P0627 - Peroral Endoscopic Myotomy for Achalasia Subtypes and Esophagogastric Outflow Obstruction: Clinical Success and GERD

Sunday, October 24, 2021

3:30 PM – 7:00 PM PT

Location: Shoreline Exhibit Hall

Has Audio

Presenting Author(s)

Andrew Li, MD

Stanford University Medical Center
Woodside, CA, United States

Andrew Li, MD¹, Alexander Podboy, MD², Woosung Kim, MD³, Micaela Esquivel, MD³, Joo Ha Hwang, MD, PhD⁴
¹Stanford University Medical Center, Woodside, CA; ²Cedars-Sinai Medical Center, Los Angeles, CA; ³Stanford University Medical Center, Stanford, CA; ⁴Stanford University Medical Center, Palo Alto, CA

Introduction: Peroral endoscopic myotomy (POEM) is an endoscopic treatment for achalasia and esophagogastric outflow obstruction (EGJOO). Prior studies have demonstrated the efficacy of POEM and a higher incidence of GERD compared to surgical myotomy and fundoplication. We aimed to characterize the experience with POEM at our institution.

Methods: We conducted a retrospective analysis of POEMs performed at a tertiary care center from 2018-2021 with subsequent follow-up and procedural testing. The primary outcome was clinical success based on the Eckardt score. Secondary outcomes included technical success, GERD-related outcomes (symptoms, esophagitis, pH study), manometry, and Intraprocedural functional lumen imaging probe (FLIP) parameters. p< 0.05 was considered significant.

Results: POEMs were performed on 119 patients over the study period. Of these, 100 had clinical follow-up and 68 patients had follow-up procedural testing. All POEMs were technically successful, typically performed in a posterior orientation. Prior to POEM, 46.2% of patients had undergone other treatment, the majority of which was botulinum toxin injection. The primary outcome of clinical success (total Eckardt score ≤ 3) was achieved in 95% of patients, with variation by subtype. Mean Eckardt score was 7.2 (±2.2 SD) before POEM which significantly improved to 0.76 (±1.3 SD) after POEM. Mean FLIP distensibility index at 50 mL significantly improved from 1.5 (±0.8 SD) before POEM to 4.6 (±2.1 SD) after POEM and 4.9 (±2.0 SD) at follow-up. The integrated relaxation pressure significantly improved from 30.7 (±14.5 SD) to 12.5 (±7.2 SD). Intraprocedural FLIP prompted additional myotomy in 6% of patients. At follow-up, 26% of patients reported GERD symptoms, and 27% used a PPI. Follow-up endoscopy identified esophagitis in 28.8% of patients, with 8.5% having LA grade B or higher, and pH probe was positive for GERD in 44% of patients. One patient required fundoplication after POEM due to GERD and adverse reaction to all PPIs.

Discussion: These data demonstrate the utility of POEM for the treatment of achalasia and EGJOO. The clinical success rate was comparable to published data, with a lower incidence of significant esophagitis (LA B or higher) compared to some studies. Limitations include the retrospective nature of this analysis and variable length of follow-up. Prospective studies are needed to determine the optimal strategy for myotomy in POEM in treating symptoms and minimizing GERD.

Figure: Retrospective analysis of POEM outcomes at a tertiary care center. Patients who underwent POEM from 2018-2021 were included. Patients were followed for clinical symptoms and underwent procedural follow-up testing with esophagogastroduodenoscopy (EGD), functional lumen imaging planimetry (FLIP), wireless capsule pH testing, and esophageal manometry (EMAN).

	Pre POEM		Post POEM		p-value (Wilcoxan rank sum)
All Patients with follow up (n=100)	Mean	SD	Mean	SD
Eckardt – total	7.25	2.16	0.76	1.33	p< 0.0000001
Percent Eckardt total ≤ 3	2.9%		95.0%
Type I Achalasia (n=8)
Eckardt – total	8.25	1.67	0.50	0.76	p< 0.001
Percent Eckardt total ≤ 3	0.0%		100.0%
Type II Achalasia (n=52)
Eckardt – total	7.17	1.98	0.58	0.91	p< 0.0000001
Percent Eckardt total ≤ 3	1.9%		98.1%
Type III Achalasia (n=27)
Eckardt – total	7.55	2.43	1.00	1.92	p< 0.0000001
Percent Eckardt total	3.4%		88.9%
Other (Variant Achalasia and EGJOO; n=13)
Eckardt - total	6.57	2.31	1.15	1.52	p< 0.001
Percent Eckardt total ≤ 3	7.1%		92.3%

Table: Eckardt scores before and after peroral endoscopic myotomy (POEM). Severity of symptoms related to achalasia or EGJOO were assessed using the Eckardt score before POEM and after POEM. The Eckardt score is a sum of subscores related to dysphagia, regurgitation, retrosternal pain, and weight loss. A nonparametric statistical test was used to compare scores before and after POEM (Wilcoxan rank sum). Clinical success was defined as a total Eckardt score ≤ 3.

Disclosures:

Andrew Li indicated no relevant financial relationships.

Alexander Podboy indicated no relevant financial relationships.

Woosung Kim indicated no relevant financial relationships.

Micaela Esquivel indicated no relevant financial relationships.

Joo Ha Hwang: Boston Scientific – Consultant. LumenDi – Consultant. Medtronic – Consultant. Micro-Tech – Consultant. Olympus – Consultant.

Andrew Li, MD¹, Alexander Podboy, MD², Woosung Kim, MD³, Micaela Esquivel, MD³, Joo Ha Hwang, MD, PhD⁴. P0627 - Peroral Endoscopic Myotomy for Achalasia Subtypes and Esophagogastric Outflow Obstruction: Clinical Success and GERD, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.