Type II achalasia with focal elevated pressures: A distinct manometric and clinical sub-group

Esophageal anatomy and physiology vary across spastic and non-spastic phenotypes of disorders of esophagogastric junction outflow

BACKGROUND

Pathophysiologic mechanisms of disorders of esophagogastric junction (EGJ) outflow are poorly understood. We aimed to compare anatomic and physiologic characteristics among patients with disorders of EGJ outflow and normal motility.

METHODS

We retrospectively evaluated adult patients with achalasia types 1, 2, 3, EGJ outflow obstruction (EGJOO) or normal motility on high-resolution manometry who underwent endoscopic ultrasound (EUS) from January 2019 to August 2022. Thickened circular muscle was defined as ≥1.6 mm. Characteristics from barium esophagram (BE) and functional lumen imaging probe (FLIP) were additionally assessed.

KEY RESULTS

Of 71 patients (mean age 56.2 years; 49% male), there were 8 (11%) normal motility, 58 (82%) had achalasia (5 (7%) type 1, 32 (45%) classic type 2, 21 (30%) type 3 [including 12 type 2 with FEPs]), and 7 (7%) had EGJOO. A significantly greater proportion of type 3 achalasia had thickened distal circular muscle (76.2%) versus normal motility (0%; p < 0.001) or type 2 achalasia (25%; p < 0.001). Type 1 achalasia had significantly wider mean maximum esophageal diameter on BE (57.8 mm) compared to type 2 achalasia (32.8 mm), type 3 achalasia (23.4 mm), EGJOO (15.9 mm), and normal motility (13.5 mm). 100% type 3 achalasia versus 0% type 1 achalasia/normal motility had tertiary contractions on BE. Mean EGJ distensibility index on FLIP was lower for type 3 achalasia (1.2 mmHg/mm2 ) and EGJOO (1.2 mmHg/mm2 ) versus type 2 (2.3 mmHg/mm2 ) and type 1 achalasia (2.9 mmHg/mm2 ).

CONCLUSIONS

Our findings suggest distinct pathologic pathways may exist: type 3 achalasia and EGJOO may represent a spastic outflow phenotype consisting of a thickened, spastic circular muscle, which is distinct from type 1 and 2 achalasia consisting of a thin caliber circular muscle layer with more prominent esophageal dilation.

Diagnostic methods to measure spastic segment and guide tailored myotomy length in type 3 achalasia

BACKGROUND

Myotomy length in type 3 achalasia is generally tailored based on segment of spasticity on high-resolution manometry (HRM). Potential of length of tertiary contractions on barium esophagram (BE) or length of thickened circular muscle on endoscopic ultrasound (EUS) to guide tailored myotomy is less understood. This study aimed to assess agreement between spastic segments lengths on HRM, BE, and EUS among patients with type 3 achalasia.

METHODS

This retrospective study included adults with type 3 achalasia on HRM between November 2019 and August 2022 who underwent evaluation with EUS and/or BE. Spastic segments were defined as HRM-distance between proximal borders of lower esophageal sphincter and high-pressure area (isobaric contour ≥70 mmHg); EUS-length of thickened circular muscle (≥1.2 mm) from proximal border of esophagogastric junction (EGJ) to the transition to a non-thickened circular muscle; BE-distance between EGJ to proximal border of tertiary contractions. Pairwise comparisons assessed for correlation (Pearson's) and intraclass correlation classification (ICC) agreement.

KEY RESULTS

Twenty-six patients were included: mean age 66.9 years (SD 13.8), 15 (57.7%) male. Spastic segments were positively correlated on HRM and BE with good agreement (ICC 0.751, [95% CI 0.51, 0.88]). Spastic segments were negatively correlated with poor agreement on HRM and EUS (ICC -0.04, [-0.45, 0.39]) as well as BE and EUS (ICC -0.03, [-0.47, 0.42]).

CONCLUSIONS & INFERENCES

Length of spastic segment was positively correlated on HRM and BE while negatively correlated when compared to EUS, supporting the common use of HRM and highlighting the uncertain role for EUS in tailoring myotomy length for type 3 achalasia.