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Assessment of Gastro-esophageal Reflux Using Endo-Flip vs Bravo

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00481949
Recruitment Status : Completed
First Posted : June 4, 2007
Last Update Posted : June 27, 2011
Information provided by:
Guy's and St Thomas' NHS Foundation Trust

Brief Summary:

Monitoring oesophageal pH provides a definitive diagnosis of patients with gastro-oesophageal reflux disease (GORD), especially those in whom the association between reflux and symptoms is uncertain and those under consideration for anti-reflux surgery. Standard ambulatory investigation is normally performed by naso-oesophageal catheter however this is associated with considerable discomfort and in turn altered behaviour which reduces reflux provoking activities. Furthermore results of catheter based ambulatory pH studies are compromised by the high variability of acid exposure in patients with suspected GORD.

Prolonging pH measurements by the catheter-free Bravo™ system from 24 to 48 and 96hrs significantly improves the consistency (reliability) and reproducibility of diagnoses based on oesophageal acid exposure, as well as the ability to associate acid reflux to symptom episodes. This improves diagnosis especially in those with intermittent symptoms.

However pH monitoring does not provide a direct assessment of the underlying pathophysiology. Incompetence of the oesophago-gastric junction (OGJ) related to disruption of its structure and function is considered to be the most important cause of GORD. A more relevant assessment of the reflux barrier may be its distensibility (i.e. the ease with which the OGJ is opened to allow retrograde passage of gastric contents); however this is not assessed by current clinical investigations.

Endo-FLIP (Crospon Medical Devices) is a new tool which assesses OGJ structure and function, and appears to provide relevant information regarding its distensibility and competence.

This study applies to using Endo-Flip to record OGJ distensibility and Bravo to record acid exposure and symptom association in patients with reflux symptoms. The variability of pH measurements and symptoms and diagnostic accuracy will be assessed over 96hrs. Endo-FLIP results will then be compared against Bravo. The outcome of post investigation therapy will then be compared with Endo-Flip and Bravo results to assess if baseline testing can predict the outcome of acid suppression therapy.

Study Hypothesis

  1. There is a positive, continuous association between OGJ distensibility measured by Endo-FLIP on % acid exposure assessed by prolonged Bravo pH monitoring
  2. The results of Endo-FLIP and prolonged Bravo predict treatment outcome of a trial of proton pump inhibitor therapy

Condition or disease
Heartburn Gastro-esophageal Reflux

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Study Type : Observational
Actual Enrollment : 50 participants
Observational Model: Case-Control
Time Perspective: Prospective
Official Title: What is the Physiologic and Clinical Relevance of Oesophagogastric Junction Distensibility? Studies Using Endo-Flip and 96 Hour Wireless pH System
Study Start Date : September 2010
Actual Primary Completion Date : May 2011
Actual Study Completion Date : May 2011

Resource links provided by the National Library of Medicine

MedlinePlus related topics: GERD Heartburn

Primary Outcome Measures :
  1. Diagnostic reliability of prolonged wireless pH monitoring and comparison oesophago-gastric junction distensibility [ Time Frame: 1 year ]
    1. To confirm improved diagnostic reliability and accuracy of prolonged pH measurement by the Bravo™ system in a large, prospective clinical trial
    2. To confirm that there is a positive, continuous association between oesophago-gastric junction (OGJ) distensibility measured by Endo-FLIP on percentage acid exposure assessed by prolonged Bravo-pH monitoring

Secondary Outcome Measures :
  1. Prediction of treatment outcome with Endo-Flip and Bravo [ Time Frame: 2 years ]

    To confirm that the results of Endo-FLIP and prolonged Bravo-pH monitoring can predict treatment outcome of a trial of proton pump inhibitor therapy:

    1. Patients with high OGJ distensibility and high reflux-symptom association with acid regurgitation or cough complain of persistent regurgitation of gastric contents on treatment.
    2. Patients with low OGJ distensibility and high reflux-association with heartburn complain of persistent heartburn
    3. Patients with low OGJ distensibility and low reflux-association with any symptom complain of atypical and dyspeptic symptoms

Biospecimen Retention:   Samples Without DNA
Biopsies taken at the gastro-oesophageal junction will be sent to histology lab and analysed as per routine histology specimens. These will be stored as all samples at our hospital are stored and only results reported by the appointed histologist will be used for analysis.

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 70 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Patients with typical reflux symptoms (heartburn, acid regurgitation)

Inclusion Criteria:

  • Provision of written, fully informed consent to undergo mechanistic procedures: Endo-FLIP, endoscopy and biopsy, 4 day wireless pH monitoring by the Bravo system
  • All subjects should be off acid suppression medication (e.g. PPI, H2RA) for at least 5 days prior to endoscopy

Exclusion Criteria:

  • Significant gastrointestinal symptoms or disease other than reflux
  • Previous upper GI surgery or interventions such as oesophageal dilatations
  • Predominant symptoms of motility disorders, e.g. dysphagia
  • Presence of major oesophageal dysmotility on manometry, e.g. achalasia
  • Significant co-morbidity requiring ongoing treatment or investigation
  • Physical, neurological or psychiatric conditions preventing repeated visits to hospital or compliance with study procedures (e.g. physical impairment/reduced mobility)
  • Pregnant at the time of enrolment
  • No haematological abnormalities (no anticoagulants)
  • No medications influencing gastrointestinal function within 3 days of the study.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00481949

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United Kingdom
Oesophageal Laboratory, GSTT
London, United Kingdom, SE1 7EH
Sponsors and Collaborators
Guy's and St Thomas' NHS Foundation Trust
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Principal Investigator: Mark Fox, MD Honorary Consultant and Senior Lecturer
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Responsible Party: Mark Fox, GuysThomasNHS Identifier: NCT00481949    
Other Study ID Numbers: 05/20702/84
First Posted: June 4, 2007    Key Record Dates
Last Update Posted: June 27, 2011
Last Verified: June 2011
Keywords provided by Guy's and St Thomas' NHS Foundation Trust:
Gastro-oesophageal reflux disease
pH measurement
symptom association
wireless pH monitoring system
Functional Heartburn
Gastro-esophageal reflux disease
Additional relevant MeSH terms:
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Gastroesophageal Reflux
Esophagitis, Peptic
Esophageal Motility Disorders
Deglutition Disorders
Esophageal Diseases
Gastrointestinal Diseases
Digestive System Diseases
Signs and Symptoms, Digestive
Peptic Ulcer
Duodenal Diseases
Intestinal Diseases
Stomach Diseases