Cricopharyngeal muscle electromyography findings in patients with gastroesophageal reflux disease.

Abstract

To analyze the grade of reflux and the behavior of the cricopharyngeal muscle (CPM) in patients with gastroesophageal reflux (GER) by means of electromyographic (EMG) analysis of CPM. Prospective clinical study. Istanbul Training and Research Hospital. Motor unit potential (MUP) recordings and kinesiological recordings of CPM were performed using a concentric needle electrode during dry material swallowing and 3-, 5-, and 10-mL water swallowing. Twenty-four patients with GER were compared with 21 healthy volunteers. GER was mild in 15 patients and moderate-to-severe in 9 patients. MUP recordings were normal in both groups during the preswallowing/postswallowing periods. Kinesiological investigations revealed that the number of patients who did not show a preswallow EMG burst had a positive correlation with the severity of reflux and the amount of liquid swallowed. Rebound bursts were observed in the patient and the control groups. Duration of preswallow and rebound bursts was similar in all groups. Duration of swallowing was shorter in mild GER patients compared with healthy volunteers and moderate-to-severe GER patients. Piecemeal deglutition during 10-mL liquid swallowing was higher in moderate-to-severe GER patients. We also found a positive correlation between the number of swallows and the severity of reflux. Needle EMG of the upper esophageal sphincter was normal in GER patients. Kinesiological evaluations showed increased piecemeal deglutition and number of swallows that correlated positively with the severity of GER.