EATURES OF ESOPHAGEAL MOTILITY AND THE ESOPHAGOGASTRIC JUNCTION IN ACHALASIA AND HIATAL HERNIA: A COMPARATIVE STUDY

Abstract

Background. Esophagogastric junction motility disorders in achalasia and hiatal hernia are accompanied by alterations in the barrier function of the lower esophageal sphincter and impaired coordination of esophageal peristaltic activity. Quantitative intraluminal pressure recording enables objective assessment of the pathophysiological mechanisms underlying these disorders and allows evaluation of intersegmental features of motor regulation.
Materials and Methods. A total of 165 patients were examined and divided into three groups: control (n = 15), achalasia (n = 50), and hiatal hernia (n = 100). Intraluminal pressure was recorded using a pneumatic balloon fixed to an endoscopic probe. Pressure in the region of the lower esophageal sphincter and the pyloroduodenal junction was measured, as well as the amplitude and period of peristaltic and rhythmic pressure oscillations. Results are presented as Me (Q25; Q75). Intergroup comparisons were performed using the Kruskal–Wallis test followed by Dunn’s post hoc test with Bonferroni adjustment for multiple comparisons.
Results and Discussion. Pressure during the passage through the lower esophageal sphincter in the hiatal hernia group was 4.52 (1.30; 12.64) mmHg and was significantly lower than in the control group, 19.54 (18.25; 20.12) mmHg, and the achalasia group, 22.80 (9.76; 43.69) mmHg (H = 51.44; p < 0.001). The peristaltic wave period was shorter in patients with hiatal hernia than in the control group (p = 0.010). The amplitude of peristaltic and rhythmic contractions did not demonstrate statistically significant intergroup differences. Changes in motor parameters were multidirectional and depended on the nosological form.
Conclusion. In this study, LES-region pressure measured during the balloon passage showed the largest intergroup contrast, caused by markedly lower values in the hiatal hernia group, and thus demonstrated the clearest between-group contrast within the applied protocol. This finding is consistent with reduced antireflux barrier competence in hiatal hernia. However, the balloon “pressure during passage” metric reflects integrated mechanical resistance and is not directly equivalent to HRM-derived basal LES pressure or integrated relaxation pressure (IRP). In achalasia, this metric did not differentiate patients from controls in our cohort and should not be interpreted as a stand-alone marker of impaired LES relaxation. Peristaltic and rhythmic activity of the esophageal body shows high variability and limited diagnostic specificity.