The level of impaired esophageal bolus transit measured by multichannel intraluminal impedance: Cross-sectional study

BACKGROUND: Esophageal motility disorders (EMDs) are often diagnosed manometrically, yet the underlying pathology is not always clear. Esophageal function testing (EFT), which incorporates manometry and multichannel intraluminal impedance (MII), is considered a useful tool in the assessment of EMDs. OBJECTIVE: This study aims to assess the most likely level of impaired bolus transit within the esophagus which may help further localize and characterize EMDs. METHODS: In a retrospective study design, we reviewed consecutive EFTs over a period of 12 months. Data included diagnosis, presenting symptoms, and EFT results of liquid and viscous swallows. Each patient underwent 10 liquid and 10 viscous swallows, and bolus transit is measured at 5, 10, 15 and 20 cm above the gastroesophageal junction (GEJ). We recorded the initial level of impaired bolus transit for each swallow. RESULTS: A total of 2358 swallows in 118 patients was included for analysis. Of these, 837 swallows (35.5%) were incompletely transmitted. The proportions of impaired bolus transit were 39%, 41%, 15.6%, 4.4% at 20 cm, 15 cm, 10 cm, and 5 cm above the GEJ, respectively. The common symptoms at presentation were dysphagia (47%), heartburn (44%), chest pain (24.6%) and regurgitation (18%). The mean lower esophageal sphincter (LES) pressure was 24 ± 13.9 mmHg whereas the mean contraction amplitude was 84 ± 46.6 mmHg. CONCLUSION: In patients with abnormal esophageal clearance, the most likely levels of impaired bolus transit are 15 and 20 cm above the GEJ. These levels of the esophagus should be a focus of attention in future studies evaluating the pathophysiology of esophageal dysmotility.