The Impact of Heller Myotomy on Integrated Relaxation Pressure in Esophageal Achalasia

BACKGROUND: A new high-resolution manometry (HRM) parameter, the integrated relaxation pressure (IRP), has been proposed for the assessment of esophageal-gastric junction (EGJ) relaxation. Our aim was to assess the effect of Heller myotomy on IRP in achalasia patients. METHODS: We prospectively collected data on achalasia patients who underwent HRM between 2009-2014. Barium swallow was used to assess esophageal diameter and shape. Manometric diagnoses were performed by using the Chicago Classification v3. All patients with a confirmed diagnosis of achalasia were treated surgically with Heller Myotomy RESULTS: One hundred thirty-nine consecutive achalasia patients (M:F = 72:67) represented the study population. All the patients had 100% simultaneous waves but 11 had an IRP < 15 mmHg. At median follow-up of 28 months, the median of IRP was significantly lower after surgery (27.4 [IQR 20.4-35] vs 7.1 [IQR 4.4-9.8]; p < 0.001), and so were the lower esophageal sphincter (LES) resting pressure (27 [IQR 18-33] vs 6 [IQR 3-11]; p < 0.001). At univariate analysis, IRP correlated with the gender, LES resting residual pressure, and dysphagia score. CONCLUSIONS: This is the first study to have examined the role of IRP in achalasia, and how it changes after surgical treatment. An increased preoperative IRP correlated directly with a more severe dysphagia. The IRP was restored to normal by Heller myotomy.