Is Non-Cardiac Chest Pain Caused by Sustained Longitudinal Smooth Muscle Contraction?

Study Overview
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Brief Summary
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Non-cardiac chest pain (NCCP) is a common disorder whose pathophysiology is poorly understood. Some evidence suggests it may be related to sustained esophageal contractions (SECs) of longitudinal smooth muscle. The investigators have previously shown that acid is a trigger for SECs and results in shortening of the esophagus. In this study, the investigators plan to prospectively evaluate esophageal shortening responses to acid in a group of patients with NCCP compared to controls. The investigators will use high resolution esophageal manometry coupled with acid infusion to evaluate shortening. The investigators hypothesize that at least a subset of patients with NCCP will have an exaggerated esophageal shortening response to acid which correlates with symptom production. If our hypothesis proves true, this may lead to a future therapeutic target in the treatment of these patients.

Official Title
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Is Non-Cardiac Chest Pain Caused by Sustained Longitudinal Smooth Muscle Contraction?

Conditions
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Chest Pain Atypical Syndrome

Intervention / Treatment
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* Other: Esophageal Manometry


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy volunteers: free of esophageal symptoms not on any acid suppressing medications Non Cardiac Chest Pain Patients: Angina like chest pain occuring at least once per month Coronary artery disease ruled out by stress test or angiogram Exclusion Criteria: pre existing motility disorder of the esophagus connective tissue disease pregnancy taking calcium channel blockers, Nitrates, Gabapentin, Narcotics, Tricyclic antidepressants, Anti seizure medications

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Non Cardiac Chest Pain Patients<br>Patients with Chest Pain where Coronary Artery Disease has been formally ruled out are to undergo esophageal manometry testing. | Other: Esophageal Manometry<br>* Both cohorts will undergo standard high resolution esophageal manometry testing. This entails a catheter passed through the nose into the esophagus and measures pressure changes with a series of wet swallows. As part of the study, we will also be instilling both weak acid and saline into the esophagus.<br>|
| Healthy Controls<br>Healthy volunteers without esophageal symptoms are to undergo esophageal manometry testing. | Other: Esophageal Manometry<br>* Both cohorts will undergo standard high resolution esophageal manometry testing. This entails a catheter passed through the nose into the esophagus and measures pressure changes with a series of wet swallows. As part of the study, we will also be instilling both weak acid and saline into the esophagus.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Change in Esophageal Length With Acid | Mean length of esophagus with acid infusion minus mean length of esophagus with saline infusion | Length at T= 20 minutes - Baseline (T=0) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Esophageal Length at Symptom Onset | Length of Esophagus as measured by manometry during acid infusion when patient reports symptoms | 20 minutes | 
| Esophageal Length at Maximal Symptom Intensity | Mean length of esophagus at peak patient reported symptom intensity with acid infusion | 20 minutes | 
| Number of Participants for Whom a Correlation Was Found Between Symptom Onset and Esophageal Shortening | Esophageal shortening will be defined as the point during the 20 minute acid infusion at which the lower esophageal sphincter begins to migrate proximally. A 2 minute window following this time point will then be used to determine if patients symptoms increased by > 2 on a visual analogue pain scale between 0 - 10. | 20 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Non Cardiac Chest Pain