title: Patients with functional heartburn are more likely to report retrosternal discomfort during wireless pH monitoring.
abstract: BACKGROUND
  Although the wireless Bravo pH system is effective, some patients experience retrosternal sensations possibly caused by esophageal sensitivity that may complicate clinical application.
  
  
  METHODS
  Ambulatory pH of 40 consecutive patients with GERD who had erosive esophagitis or nonerosive reflux disease, were monitored for 2 days with the Bravo system. Results were stratified and compared on the basis of self-awareness of the intraesophageal capsule.
  
  
  RESULTS
  Pathologic acid reflux was diagnosed in 20 patients and normal reflux was diagnosed in 20 patients. Seventeen patients (42.5%) reported retrosternal discomfort, and 12 of them (70.6%) had normal reflux. Patients with retrosternal discomfort were less likely to have moderate endoscopic esophagitis, i.e., Los Angeles classification grades B, C, and D endoscopic esophagitis (p = 0.006), and were less likely to have significantly elevated esophageal acid exposure (p = 0.0036) than those who did not perceive the discomfort. Reported discomfort was not associated with age, gender, or the presence of endoscopic esophagitis.
  
  
  CONCLUSIONS
  The negative correlation between Bravo-capsule-induced retrosternal discomfort and esophageal-acid exposure indicates modified mechanical afferent nerve function after long-term acid stimulation. Capsule-induced retrosternal discomfort in the presence of normal acid exposure suggests functional heartburn.
authors.affiliation: Department of Internal Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Yi-Chia
authors.initials: YC
authors.lastname: Lee
authors.forename: Hsiu-Po
authors.initials: HP
authors.lastname: Wang
authors.forename: Han-Mo
authors.initials: HM
authors.lastname: Chiu
authors.forename: Shih-Pei
authors.initials: SP
authors.lastname: Huang
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Tu
authors.forename: Ming-Shiang
authors.initials: MS
authors.lastname: Wu
authors.forename: Jaw-Town
authors.initials: JT
authors.lastname: Lin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002637:Chest Pain / Q000209:etiology*; D050782:Esophageal pH Monitoring / Q000009:adverse effects / Q000295:instrumentation*; D004941:Esophagitis / Q000175:diagnosis* / Q000378:metabolism; D004945:Esophagoscopy; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis* / Q000378:metabolism; D006356:Heartburn / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000009:adverse effects / Q000295:instrumentation*