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Updated: May 5, 2026

Real-Time, Semi-Automated Fluorescent Measurement of the Airway Surface Liquid pH of Primary Human Airway Epithelial Cells
Published on: June 13, 2019
ECG record during changes in oesophageal pH
Abstract:
Seventeen patients with non-cardiac chest pain were investigated by simultaneous ambulatory 24 hour ECG and oesophageal pH monitoring. While 11 patients lowered their oesophageal pH below 4 for a significant percentage, (3.4%) of recorded time and experienced chest pain, no simultaneous ECG changes occurred. In 10 patients chest pain was reproduced by an oesophageal acid perfusion test (Bernstein test). No changes in ECG record during the test were shown. We conclude that although reflux oesophageal pain may be difficult to differentiate from cardiac pain, clinically oesophageal pH changes do not produce any ECG changes.
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