UNEXPLAINED CHEST PAIN - THE HYPERSENSITIVE, HYPERREACTIVE, AND POORLY COMPLIANT ESOPHAGUS

Objective: To determine whether neuromuscular dysfunction of the esoph agus causes chest pain in patients in whom no disease is found on card iac work-up, upper gastrointestinal endoscopy, esophageal manometry, a nd 24-hour pH studies. Design: Prospective study. Setting: Tertiary re ferral center. Patients: 24 consecutive patients and 12 healthy contro ls. Measurements: A new technique, impedance planimetry, was used to m easure the sensory, motor, and biomechanical properties of the human e sophagus. The impedance planimeter, which consists of a probe with fou r ring electrodes, three pressure sensors, and a balloon, simultaneous ly measures intraluminal pressure and cross-sectional areas. This allo ws calculation of the biomechanical variables of the esophageal wall. Results: Stepwise balloon distentions from 5 to 50 cm H2O induced a fi rst sensation at a mean pressure (+/- SD) of 15 +/- 9 cm H2O in patien ts and 30 +/- 11 cm H2O in controls (P < 0.001). Moderate discomfort a nd pain were reported by 20 of 24 patients (83%) at 26 +/- 9 cm H2O an d at 36 +/- 9 cm H2O, respectively, but by none of the controls (P < 0 .001). Typical chest pain was reproduced in 20 of 24 patients (83%). I n patients, the reactivity of the esophagus to balloon distention was greater (P = 0.01), the pressure elastic modulus was higher (P = 0.02) , and the tension-strain association showed that the esophageal wall w as less distensible (P = 0.02). Distention excited tertiary contractio ns and secondary peristalsis at a lower threshold of pressure (P = 0.0 5) and with a higher motility index in patients than in controls (P = 0.04). Conclusion: In patients with chest pain and normal cardiac and esophageal evaluations, impedance planimetry of the esophagus reproduc es pain and is associated with a 50% lower sensory threshold for pain, a 50% lower threshold for reactive contractions, and reduced esophage al compliance.