Relationship Between Lower Esophageal Sphincter Muscles Thickness and Their Response to Pneumatic Dilation in Patients With Achalasia.

Background: Prognostic factors play a major role in managing achalasia patients treated with pneumatic dilatation (PD) and understanding the pathophysiology of the disease. In this regard, the muscular thickness of the lower esophageal sphincter (LES) has drawn attention in recently published studies.

Methods: Patients with newly diagnosed achalasia were included consecutively in this study, and Endoscopic Ultrasound (EUS) was used to determine the thickness of longitudinal and circular muscles of LES. To determine the recurrence of symptoms, patients were followed up for one year using the Eckardt questionnaire. The relationship between pre-treatment LES muscle thickness and symptom recurrence was investigated.

Results: Seventeen of nineteen treated patients were enrolled in this study and the data of sixteen patients was analyzed. Although not statistically significant, those with thinner LES had recurrent symptoms ( p-value = 0.08). Patients with a thicker LES (5.1 mm vs. 4.6 mm) initially responded better to pneumatic dilatation ( p-value = 0.03). After initial therapy, severe pain (daily pain) was strongly associated with symptom recurrence.

Conclusions: Severe retrosternal chest pain and a thin LES appear to be surrogate markers for advanced disease and poor outcomes. Pre-treatment integrated relaxation pressure (IRP) seems to be a promising predictor of PD prognosis. Due to the study's heterogeneous population, the findings cannot be generalized to all achalasia patients, and larger-scale studies are necessary to confirm these findings.