434 Response to Multiple Rapid Swallows Shows Impairment of Inhibitory Pathways in Patients With Distal Esophageal Spasm

Abstract

INTRODUCTION: Distal esophageal spasm (DES) is a motility disorder characterized by premature contraction of the esophageal body during single swallows. It is thought to be due to impairment of esophageal inhibitory pathways, but studies to support this are limited. Assessment of response to multiple rapid swallows (MRS) during high-resolution esophageal manometry (HRM) enables detection of impaired inhibition during MRS. Healthy subjects respond to MRS by deglutitive inhibition during the MRS sequence. We hypothesize that deglutitive inhibition is impaired in DES patients. Aim: compare response to MRS in DES patients and healthy controls. METHODS: Response to MRS was evaluated in 19 DES patients and 24 asymptomatic healthy controls. Demographic and symptom data were extracted from a prospectively maintained motility database. Patients with history of prior gastroesophageal surgery, endoscopic myotomy (POEM), pneumatic dilation, esophageal botulinum toxin injection within 6 months of HRM, and esophageal stricture were excluded. HRM was performed with a solid state catheter with 36 circumferential pressure sensors 1-cm apart; ten 5-ml liquid swallows were given followed by MRS sequence, analyzed with Manoview software (Medtronic). Esophagogastric junction integrated relaxation pressure (IRP), distal contractile integral (DCI), and distal latency (DL) were calculated, and Chicago Classification v3.0 was applied to diagnose DES (defined by ≥ 2 swallows with DL ≤ 4.5 sec). Response to MRS was evaluated for complete versus impaired inhibition (contractility with DCI > 100 mmHg-sec-cm during MRS), and presence of post MRS contraction augmentation (DCI post MRS greater than single-swallow mean DCI). Chi-Square and Fisher’s exact test were used for statistical analysis. RESULTS: Demographics and symptom data are shown in Table 1. Patients with DES were older and more symptomatic than controls. Impaired inhibition of peristalsis during MRS was significantly more frequent in DES compared to controls (89% vs 0%, P < 0.001, Figure 1). The proportion of subjects with augmentation post MRS was similar for both groups (37% vs 38%, P = 1.00), but mean DCI post MRS was higher in DES than controls (3788 vs 1239, P = 0.013). CONCLUSION: Impaired deglutitive inhibition during MRS is present in the majority of patients with DES, supporting impaired inhibitory pathways in the esophagus as a mechanism of action in this disorder.