Bravo 48-hour Wireless pH Monitoring in Patients With Non-cardiac Chest Pain. Objective Gastroesophageal Reflux Disease Parameters Predict the Responses to Proton Pump Inhibitors

Is Noncardiac Chest Pain Truly Noncardiac?

Many causes of noncardiac chest pain (NCCP) have been studied and gastroesophageal reflux disease is considered to be the major cause. However, studies have reported that treatment with a proton pump inhibitor does not effectively provide relief for NCCP-related symptoms, and these symptoms frequently recur. These findings suggest that patients with cardiac disease may be excluded completely from the NCCP group. Several examinations can be conducted to verify the presence of cardiac disease. Such examinations include the assessment of biochemical markers, rest and exercise electrocardiogram, echocardiography, cardiac computed tomography, stress myocardial perfusion imaging, cardiac magnetic resonance imaging, and coronary angiography (CAG). However, the presence of functional coronary artery diseases (CADs), such as vasospastic angina and/or microvascular angina, cannot be detected using these modalities. These functional CADs can be diagnosed by CAG with spasm-provocation testing and/or physiological coronary measurement. Thus, when a patient who is suspected of having NCCP takes a proton pump inhibitor and does not respond well, further examination-including assessment for possible functional CADs-may be needed.

British Society of Gastroenterology guidelines for oesophageal manometry and oesophageal reflux monitoring

These guidelines on oesophageal manometry and gastro-oesophageal reflux monitoring supersede those produced in 2006. Since 2006 there have been significant technological advances, in particular, the development of high resolution manometry (HRM) and oesophageal impedance monitoring. The guidelines were developed by a guideline development group of patients and representatives of all the relevant professional groups using the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool. A systematic literature search was performed and the GRADE (Grading of Recommendations Assessment, Development and Evaluation) tool was used to evaluate the quality of evidence and decide on the strength of the recommendations made. Key strong recommendations are made regarding the benefit of: (i) HRM over standard manometry in the investigation of dysphagia and, in particular, in characterising achalasia, (ii) adjunctive testing with larger volumes of water or solids during HRM, (iii) oesophageal manometry prior to antireflux surgery, (iv) pH/impedance monitoring in patients with reflux symptoms not responding to high dose proton pump inhibitors and (v) pH monitoring in all patients with reflux symptoms responsive to proton pump inhibitors in whom surgery is planned, but combined pH/impedance monitoring in those not responsive to proton pump inhibitors in whom surgery is planned. This work has been endorsed by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG) under the auspices of the oesophageal section of the BSG.

Safety and Efficacy of Wireless pH Monitoring in Patients Suspected of Gastroesophageal Reflux Disease: A Systematic Review

INTRODUCTION

The primary aim of this systematic review was to determine the safety, technical efficacy, and effectiveness of 48-hour wireless pH monitoring (WM) for gastroesophageal reflux disease (GERD), compared with no pH monitoring in patients who failed to tolerate a catheter. In the absence of eligible studies, the secondary aim was to determine these performance characteristics for WM relative to catheter-based pH monitoring (CBM) in patients suspected of GERD, who are able to tolerate a catheter.

METHODS

A protocol was registered on the PROSPERO database (CRD42013005852) before conducting the systematic review, which included the study selection criteria, and critical appraisal methods. Several key databases were searched to identify eligible comparative studies.

RESULTS

Chest pain occurred more often with WM compared with CBM; however, other adverse events were reported less frequently with WM. Technical failures, mostly due to attachment failures and early capsule detachments, were 3 times higher with WM, compared with CBM, [pooled relative risk (from meta-analysis)=3.3; 95% confidence interval, 1.63-6.81; I=0%; P=0.012; k=8). The sensitivity and specificity of WM varied widely, depending on type of analysis, monitoring time, capsule placement, reference standard, and diagnostic threshold.

DISCUSSION

WM is usually better tolerated than CBM but has more technical problems. Test accuracy was highly variable between studies; therefore, conclusions could not be drawn regarding the performance of the 2 tests. To make meaningful comparisons between WM and CBM a consensus is needed on the diagnostic threshold for GERD, monitoring time, appropriate capsule positioning, and the reference standard.

A Review of Diagnosis of GERD

The prevalence of gastroesophageal reflux disease (GERD) and the incidence of some of its complications have risen strikingly over the last few decades. With the accumulation in our understanding on the pathophysiology of GERD along with the development of proton pump inhibitors, the diagnostic and therapeutic approaches to the GERD have changed dramatically over the past decade. However, The GERD still poses a problem to many clinicians since the spectrum of the disease has evolved to encompass more challenging presentations such as refractory GERD and extraesophageal manifestations. The aim of this article was to provide a review of available current diagnostic tests of the GERD, includes proton pump inhibitor test, ambulatory pH monitoring, impedance pH monitoring, mucosa impedance, and high resolution manometry. This review discusses different modalities for the work up of GERD.

[Current Status of Translational Research on Gastroesophageal Reflux Disease]

The prevalence of gastroesophageal reflux disease (GERD) and the incidence of some of its complications have risen strikingly over the last few decades. With the increase in our understanding of the pathophysiology of GERD along with the development of proton pump inhibitors, the diagnostic and therapeutic approaches to GERD have changed dramatically over the past decade. However, GERD still poses a problem to many clinicians since the spectrum of the disease has evolved to encompass more challenging presentations such as refractory GERD and extra-esophageal manifestations. The aim of this article is to provide a review of available current translational research on GERD. This review includes acid pocket, ambulatory pH monitoring, impedance pH monitoring, mucosa impedance, and high resolution manometry. This article discusses current translational research on GERD.

Evaluation of Gastroesophageal Reflux Disease Using the Bravo Capsule pH System

Gastroesophageal reflux disease (GERD) is a disease predominantly seen in the West but there is a rising trend in Asia. Ambulatory 24-hour catheter-based pH monitoring has been the de facto gold standard test for GERD that correlates symptoms with acid reflux episodes. However, drawbacks such as patients’ discomfort, and catheter displacement render the test as cumbersome and error-prone. The Bravo pH wireless system is designed to be user-friendly and has an added advantage of prolonged pH monitoring. The system is comparable to the catheter-based pH monitoring system in terms of diagnostic yield and symptom-reflux association. Indications include evaluation of patients with refractory GERD symptoms and prior to anti-reflux surgery. Bravo utilizes a wireless pH-sensing capsule with a complete prepackaged system, and a data processing software. The capsule may be positioned indirectly using endoscopic or manometric landmarks or under direct endoscopic guidance. Optimal threshold cut-off values are yet to be standardized but based on available studies, for the Asian population, it may be recommended for total % time pH < 4 of 5.8 over 48 hours. Cost is a limitation but capsule placement is relatively safe although technical failures may be seen in small percentage of cases.

Association between reflux and symptoms during ambulatory reflux monitoring: pros and cons of existing methods

Ambulatory reflux monitoring provides information on the quantity of gastroesophageal reflux and, if symptoms are registered during the study, provides insights into the relation between symptoms and reflux. Several symptom-reflux association analysis indices have been developed to express the relationship between onset of symptom and reflux in a numerical way. One of these indices is the binomial symptom index, introduced by Ghillebert et al. in 1990. The binomial symptom index can be used to study the relationship between symptoms and acid reflux. In this issue of Neurogastroenterology and Motility Barriga-Rivera et al. describe the use of Monte Carlo simulations to investigate the effect of random changes in reflux rates and symptom occurrences on binomial symptom index outcome. Their analysis shows that this index can be used to measure the strength of reflux symptom association. Performing symptom-reflux association analysis is important as the outcome has been shown to be reproducible and can be used as a predictor to response to acid-suppressive treatment. Despite some limitations, use of symptom-reflux association analysis is a valuable clinical tool that can provide unique insights into the cause of a patient's symptoms.

Acid reflux in patients with coronary artery disease and refractory chest pain

OBJECTIVE

To investigate the influence of acid reflux on chest pain and ischemic events and the effects of cardiac drugs on acid reflux in patients with coronary artery disease (CAD) and refractory chest pain.

METHODS

Simultaneous 24-hour esophageal pH monitoring and 24-hour continuous electrocardiogram (ECG) (Holter) results were obtained for 64 patients. Ischemic events and cardiac drug prescriptions were compared between the patients with and without gastroesophageal reflux disease (GERD). Patients fulfilling the GERD criteria received 14-day therapy with omeprazole at a dose of 20 mg bid. The results of the 24-hour pH monitoring, Holter and the SF-36 questionnaire were compared before treatment and again after two weeks of therapy.

RESULTS

GERD was identified in 38 (69%) patients, with 49% of all chest pain occurring in association with acid reflux. A higher incidence (p=0.033) and longer duration (p=0.040) of ischemic events were observed in the GERD (+) patients. More frequent combined use of cardiac drugs was found in the GERD (+) patients. However, fewer ischemic events and greater total SF-36 survey scores were noted after PPI therapy in the GERD (+) patients.

CONCLUSION

Acid reflux is common in patients with CAD and refractory chest pain. Refractory chest pain in patients with CAD can be partially noncardiac chest pain (NCCP) secondary to acid reflux. The combined use of common cardiac drugs may predispose or aggravate GERD. Short-term proton pump inhibitor (PPI) therapy not only restores a normal esophageal pH, but also significantly improves the general health-related quality of life (HRQL) of patients.