Predictive factors associated with the success of pneumatic dilatation in Japanese patients with primary achalasia: a study using high-resolution manometry.

BACKGROUND/AIMS A new classification of achalasia using high-resolution manometry (HRM) has recently been suggested. Pneumatic dilatation (PD) is a common treatment for primary achalasia. The usefulness of the new classification and HRM for the treatment and follow-up of patients after PD is unknown. The aim of this study was to evaluate the PD effectiveness and the predictive factors of success in Japanese patients with achalasia using HRM and the new classification of achalasia. METHODS Twenty-five patients were diagnosed with primary achalasia using HRM and treated by PD in our hospital. We evaluated symptom scores and esophageal manometry 6 and 12 months after the first PD. RESULTS After the first PD treatment, remission occurred in 24 out of 25 (96.0%) patients at 6 months and in 19 out of 25 (76.0%) patients at 12 months. With the new classification of achalasia, the success rates were 83.3, 80.0 and 50% for types I, II and III, respectively, 12 months after PD. The median age of the successful group was significantly greater than that of the failure group (47.1 vs. 37.0 years, p < 0.05). The median residual lower esophageal sphincter (LES) pressure 6 months after PD in the successful group was significantly lower than that of the failure group (9.0 vs. 15.5 mm Hg, p < 0.05). CONCLUSION Good predictors of PD success were old age (>40 years) and residual LES pressures less than 15 mm Hg 6 months after PD.