Achalasia: Prospective Evaluation of Relationship Between Lower Esophageal Sphincter Pressure, Esophageal Transit, and Esophageal Diameter and Symptoms in Response to Pneumatic Dilation

The aims of this study were to investigate a group of patients with achalasia prospectively to determine (1) the relationship between changes in symptoms and esophageal motor function in response to pneumatic dilation and (2) the effects of the balloon size as well as the frequency and duration of inflation on the outcome of treatment. Fourteen patients with achalasia who were symptomatic for a median duration of 27 months participated in the study. The patients were randomized to one combination of the following pneumatic dilation conditions: a 30- or 35-mm balloon dilator, one or two balloon inflations, and 20, 40, or 60 seconds per balloon inflation. A comprehensive assessment of their symptoms and esophageal motility, transit, and diameter was performed before and 3 months after pneumatic dilation. Pneumatic dilation provided significant relief of dysphagia (P<0.01), but other symptoms (heartburn, regurgitation, and chest pain) remained unchanged. Pneumatic dilation also caused a significant decrease in lower esophageal sphincter pressure and esophageal diameter and improved esophageal emptying of a solid bolus. Nevertheless, no significant association was detected between changes in the symptom score for dysphagia and changes in objective response measures as a result of pneumatic dilation. Changes in the symptom score for dysphagia or objective responses were similar regardless of the size of the dilator used or the frequency and duration of the balloon inflations. We conclude that no one particular objective determination of esophageal motor function is a reliable predictor of the symptomatic response to pneumatic dilation and that the symptomatic response does not depend on the size of the dilator, the frequency of balloon inflations, or the duration of inflation.