Abnormal esophagocardiac reflex in patients with non-cardiac chest pain

As the mechanoreceptor stimulation of the esophagus activates an esophagocardiac inhibitory reflex, with possible cardiac hypokinetic arrhythmias, we investigated whether patients with non-cardiac chest pain have this reflex, which could represent a source of risk in predisposed individuals during the intraesophageal balloon distension test. Electrocardiogram readings were recorded in nine patients with non-cardiac chest pain (group A), the esophageal origin of which was diagnosed with cardiac and esophageal examinations, in 10 patients with hyperkinetic esophageal motor disorders without chest pain (group B), and in eight normal subjects used as controls (group C), after swallowing solid boluses and during intraesophageal balloon inflation at 100 mmHg for 10 s. The percent variation of the R-R interval from its mean basal value to its highest value observed after stimulation was calculated. Solid swallows induced an increase in heart rate followed by a decrease that was significantly higher in group B than group C, while group A was not significantly different from group C. Balloon inflation induced a significant decrease in heart rate in all groups, but in group A the degree of decrease was significantly lower than in groups B and C. In conclusion, esophageal wall distension, either as a result of solid bolus or balloon inflation, elicits an inhibitory esophagocardiac reflex that is higher than normal in patients with hyperkinetic esophageal motor disorders without pain and lower than normal in patients with non-cardiac chest pain of esophageal origin, who, consequently, have nothing to fear from this procedure.