Bravo capsule pH monitoring

Towards multifunctional robotic pills

Robotic pills leverage the advantages of oral pharmaceutical formulations-in particular, convenient encapsulation, high loading capacity, ease of manufacturing and high patient compliance-as well as the multifunctionality, increasing miniaturization and sophistication of microrobotic systems. In this Perspective, we provide an overview of major innovations in the development of robotic pills-specifically, oral pills embedded with robotic capabilities based on microneedles, microinjectors, microstirrers or microrockets-summarize current progress and applicational gaps of the technology, and discuss its prospects. We argue that the integration of multiple microrobotic functions within oral delivery systems alongside accurate control of the release characteristics of their payload provides a basis for realizing sophisticated multifunctional robotic pills that operate as closed-loop systems.

Role of Endoscopy in Motility Disorders of Upper Gastrointestinal Tract

Gastrointestinal motility disorders have a wide range of symptoms and affect patients' quality of life. With the advancement of endoscopy, the diagnostic and therapeutic roles of endoscopy in motility disorders is becoming more significant. Endoscopy is necessary to rule out possible organic diseases in patients with suspected motility disorders and provide significant clues for their diagnosis. Moreover, interventional endoscopy may be a primary or alternative treatment option for selected patients with motility disorders, and it is becoming a promising field as new therapeutic applications are developed and utilized for various motility disorders. This review may provide suitable indications for the use of endoscopy in diagnosing and treating motility disorders of the upper gastrointestinal tract.

A SIGE-SINGEM-AIGO technical review on the clinical use of esophageal reflux monitoring

Patients with esophageal symptoms potentially associated with gastroesophageal reflux disease such as heartburn, regurgitation, chest pain, or cough represent one of the most frequent reasons for referral to gastroenterological evaluation. The utility of esophageal reflux monitoring in clinical practice is: (1) to accurately define reflux burden, (2) to segregate patients according to reflux monitoring results as true GERD, reflux hypersensitivity and functional heartburn, and (3) to establish a treatment plan. With this in mind, in the last decade, investigations and technical advances, with the introduction of impedance-pH monitoring and wireless pH capsule, have enhanced our understanding and management of GERD. The following recommendations were discussed and approved after a comprehensive review of the medical literature pertaining to reflux testing techniques and their recent application. This review created under the auspices of the Società Italiana di Gastroenterologia ed Endoscopia Digestiva (SIGE), Società Italiana di Neuro-Gastro-Enterologia e Motilità (SINGEM) and Associazione Italiana Gastroenterologi ed Endoscopisti Digestivi Ospedalieri (AIGO) is intended to help clinicians in applying reflux studies in the most fruitful manner within the context of their patients with esophageal symptoms.

Wireless esophageal pH capsule for patients with gastroesophageal reflux disease: A multicenter clinical study

AIM: To investigate the feasibility and safety of pH capsule to monitor pH in patients with gastroesophageal reflux disease (GERD).

METHODS: Ninety-one patients with symptoms suggestive of GERD were enrolled in this study, 46 of whom were randomized to the pH capsule group; the remaining 45 patients used the conventional catheter and pH capsule simultaneously. The pH data and traces were recorded via automatic analysis, and capsule detachment was assessed using X-ray images. All of the patients were required to complete a questionnaire regarding tolerance with the capsule.

RESULTS: The capsules were successfully attached on the first attempt, and no early detachment of the capsules was observed. Compared to the 24-h pH data recorded with the conventional catheter, the data collected with the pH capsule showed no significant differences in 24-h esophageal acid exposure. The measurements of esophageal acid exposure over 24 h collected with the two devices showed a significant correlation (r² = 0.996, P < 0.001). Capsule detachment occurred spontaneously in 89 patients, and 2 capsules required endoscopic removal due to chest pain. The capsule was associated with less interference with daily activity.

CONCLUSION: The wireless pH capsule provides a feasible and safe method for monitoring gastroesophageal reflux and therefore may serve as an important tool for diagnosing GERD.

Comparative analysis of primary repair vs resection and anastomosis, with laparostomy, in management of typhoid intestinal perforation: results of a rural hospital in northwestern Benin

Background

Wireless esophageal pH monitoring system is an important approach for diagnosis of gastroesophageal reflux disease (GERD), the aim of this study is to test the tolerability and utility of the first wireless esophageal pH monitoring system made in China, and evaluate whether it is feasible for clinical application to diagnose GERD.

Methods

Thirty patients from Department of Gastroenterology of The First Affiliated Hospital of Chongqing Medical University who were suspected GERD underwent JSPH-1 pH capsule. The capsule was placed 5 cm proximal to the squamocolumnar junction (SCJ) by endoscopic determination, the data was recorded consecutively for 48 hours. Then all pH data was downloaded to a computer for analysis. The discomforts reported by patients were recorded.

Results

30 patients were placed JSPH-1 pH capsule successfully and completed 24-hour data recording, 29 patients completed 48-hour data recording. One patient complained of chest pain and required endoscopic removal. No complications and interference of daily activities were reported during data monitoring or follow-up period. 48-hour pH monitoring detected 15 patients of abnormal acid exposure, on day1 detected 9 patients, the difference had statistical significance (P<0.01). Positive symptom index (SI) was identified in 3 patients with normal pH data in both 24-hours. In total, 48-hour monitoring increased diagnosis of GERD in 9 patients.

Conclusion

48-hour esophageal pH monitoring with JSPH-1 wireless pH monitoring system is safe, well tolerated and effective. It can be feasible for clinical application to diagnose GERD.

Esophagogastroduodenoscopy with conscious sedation does not interfere with catheter-based 24-h pH monitoring

AIM: To investigate the impact of esophagogastroduodenoscopy with conscious sedation on the subsequent 24-h catheter-based pH monitoring.

METHODS: Fifty patients with extra-esophageal symptoms of gastroesophageal reflux disease undergoing ambulatory dual-probe 24-h pH monitoring were enrolled from March 2010 to August 2011. All of the data were collected prospectively and analyzed retrospectively. Thirty-six patients (72%, group A) underwent pH monitoring shortly after esophagogastroduodenoscopy (EGD) with conscious sedation, and 14 patients (28%, group B) underwent pH monitoring without conscious sedation. The 24-h pH data from two time periods were analyzed: the first 4 h (Period I) and the remaining time of the study (Period II).

RESULTS: The mean age of the patients was 49.6 ± 12.5 years; 20 patients (40%) were men. The baseline data, including age, sex, body mass index, reflux esophagitis, the Reflux Symptom Index, and the Reflux Findings Score, were comparable between the two groups. The percentage of total time with a pH < 4 and the frequency of acid reflux during Period I were not significantly different between the two groups, as measured using both pharyngeal (0.03% ± 0.10% vs 0.07% ± 0.16%, P = 0.32; and 0.07 ± 0.23 episodes/h vs 0.18 ± 0.47 episodes/h, P = 0.33, respectively) and esophageal probes (0.96% ± 1.89% vs 0.42% ± 0.81%, P = 0.59; and 0.74 ± 1.51 episodes/h vs 0.63 ± 0.97 episodes/h, P = 0.49, respectively). The percentage of total time with a pH < 4 and the frequency of acid reflux were also not significantly different between Periods I and II in group A patients, as measured using both pharyngeal (0.03% ± 0.10% vs 0.23% ± 0.85%, P = 0.21; and 0.07 ± 0.23 episodes/h vs 0.29 ± 0.98 episodes/h, P = 0.22, respectively) and esophageal probes (0.96% ± 1.89% vs 1.11% ± 2.57%, P = 0.55; and 0.74 ± 1.51 episodes/h vs 0.81 ± 1.76 episodes/h, P = 0.55, respectively).

CONCLUSION: EGD with conscious sedation does not interfere with the results of subsequent 24-h pH monitoring in patients with extra-esophageal symptoms of gastroesophageal reflux disease.

Impact of prolonged 48-h wireless capsule esophageal pH monitoring on diagnosis of gastroesophageal reflux disease and evaluation of the relationship between symptoms and reflux episodes

CONTEXT

Gastroesophageal reflux disease is one of the most common digestive diseases and an important cause of distress to patients. Diagnosis of this condition can require ambulatory pH monitoring.

OBJECTIVES

To determine the diagnostic yield of a wireless ambulatory pH monitoring system of 48-hours, recording to diagnose daily variability of abnormal esophageal acid exposure and its symptom association.

METHODS

A total of 100 consecutive patients with persistent reflux symptoms underwent wireless pH capsule placement from 2004 to 2009. The wireless pH capsule was deployed 5 cm proximal to the squamocolumnar junction after lower esophageal sphincter was manometrically determined. The pH recordings over 48-h were obtained after uploading data to a computer from the receiver that recorded pH signals from the wireless pH capsule. The following parameters were analyzed: (1) percentual time of distal esophageal acid exposure; (2) symptom association probability related to acid reflux. The results between the first and the second day were compared, and the diagnostic yield reached when the second day monitoring was included.

RESULTS

Successful pH data over 48-h was obtained in 95% of patients. Nearly one quarter of patients experienced symptoms ranging from a foreign body sensation to chest pain. Forty-eight hours pH data analysis was statistically significant when compared to isolated analysis of day 1 and day 2. Study on day 2 identified seven patients (30.4%) that would be missed if only day 1 was analyzed. Three patients (18.7%) out of 16 patients with normal esophageal acid exposure on both days, showed positive symptom association probability, which generated an increase in diagnostic yield of 43.4%.

CONCLUSION

Esophageal pH monitoring with wireless capsule is safe, well tolerated, does not require sedation. The extended 48-h period of study poses an increased yield to diagnose gastroesophageal reflux disease patients.

Advances in diagnostic testing for gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) contributes substantially to morbidity and to costs in the United States health care system. The burden of this disease has resulted in attempts at improving diagnosis and characterizing patients. Numerous research and technical advances have enhanced our understanding of both the utility and limitations of a variety of diagnostic modalities. The purpose of this review is to highlight recent advances in GERD diagnostic testing and to discuss their implications for use in clinical practice. Topics addressed include esophageal pH monitoring, impedance testing, symptom association analyses, narrow-band imaging, and histopathology.

Technical problems produced by the Bravo pH test in nonerosive reflux disease patients

AIM: To evaluate the technical failures of the Bravo pH test in a population with nonerosive gastroesophageal reflux disease.

METHODS: Over the course of a year, we prospectively studied a population of 66 nonerosive reflux disease patients who received a Bravo pH test. The number and frequency of all technical failures were documented, quantified and analyzed.

RESULTS: A total of 66 patients, with a mean age of 41.7 years, were studied. Technical failures occurred in 15.15% of the sample. The most frequent failures were due to poor data reception (4.5%), early dislodgement (4.5%) and capsule removal (6.1%).

CONCLUSION: The Bravo capsule pH test involves a low but non-negligible rate of technical problems, a fact that must always be considered by physicians.

Use and utility of the Bravo pH capsule

The single technological advancement that Bravo pH monitoring offers over conventional pH monitoring is the elimination of the transnasal catheter. This was not a trivial advance in terms of technologic achievement. Development of a delivery system that could temporarily place a wireless capsule on the esophageal mucosa was extremely difficult to envision given the fact that the esophageal body is not conducive to retaining a foreign body. Thus, the delivery system and the ability to attach the pH capsule to the wall are what make the Bravo system unique. This approach has the potential to improve tolerance and obtain pH studies for durations greater than 24 hours; however, it still lacks the ability to measure nonacid reflux and also the ability to distinguish swallow events from true reflux. This review will highlight the advantages of the Bravo system and how it should be used.

The Bravo pH capsule system

Limitations of existing pH recording methodology have been the impetus for the emergence of new technologies focused on improving ambulatory pH monitoring. The Bravo pH capsule system (Bravo, Medtronic, Shoreview, MN) is one of the recent advances that utilize a wireless system to improve patient compliance and extend the period of monitoring. These changes could potentially improve diagnostic accuracy along with patient acceptance. Given this fact, the following review will evaluate the potential benefits that wireless pH monitoring may have over conventional catheter based pH monitoring based on the available data. In addition, we will also focus on the technical aspects related to its safety, tolerability and diagnostic accuracy.

Bravo (wireless) ambulatory esophageal pH monitoring: How do day 1 and day 2 results compare?

AIM: To investigate if differences exist for patients’ gastroesophageal reflux as measured by the Bravo ambulatory esophageal pH system between d 1 and d 2.

METHODS: A retrospective study of 27 consecutive adult patients who underwent Bravo esophageal pH monitoring was performed. Patients underwent EGD under IV conscious sedation prior to Bravo placement. Acid reflux variables and symptom scores for d 1 were compared to d 2.

RESULTS: The mean doses of fentanyl and midazolam were 90.4 μg and 7.2 mg, respectively. D 1 results were significantly more elevated than d 2 with respect to total time pH < 4, upright position reflux, and mean number of long refluxes. No statistical difference was noted between the two days for supine position reflux, number of refluxes, duration of longest reflux, episodes of heartburn, and symptom score.

CONCLUSION: Patients undergoing Bravo esophageal pH monitoring in association with EGD and moderate conscious sedation experience significantly more acid reflux on d 1 compared to d 2. The IV sedation may be responsible for the increased reflux on d 1. Performed this way, 48-h Bravo results may not be entirely representative of the patients’ true GE reflux profile.

Endosurgery: what do we need?

A paradigm shift in therapeutic endoscopy occurred with the advent of mucosectomy for the treatment of mucosal neoplasms and suture plication for gastroesophageal reflux disease. The objectives changed from finding simple, easy, and quick alternatives to surgery to reproducing surgical results. A radical version of flexible endoscopy has emerged to meet new goals of full-thickness resections, creation of anastomoses, and lumen reconfiguration. This will require a new generation of endosurgical tools that cut, stitch, and staple with added dimensions of multiaxis orientation and triangulation.

48-Hour pH monitoring increases the risk of false positive studies when the capsule is prematurely passed

Ambulatory wireless 48-h esophageal pH monitoring (Bravo Medtronic, Shoreview, MN, USA) has been shown to be more sensitive in detecting abnormal esophageal acid exposure compared with transnasal 24-h pH probes. However, accurate interpretation of the wireless monitoring data is paramount when contemplating surgical intervention for those with gastroesophageal reflux disease. The aim of this study is to evaluate the incidence of false-positive interpretations of this wireless monitoring data secondary to premature transit of the Bravo capsule into the stomach and subsequently into the duodenum prior to the completion of the 48-h study period. We reviewed 100 consecutive Bravo pH studies at our University Esophageal Motility Center. There were 58 women and 42 men included in our evaluation. Premature transit of the Bravo capsule into the stomach and subsequently into the small bowel was defined by a prolonged gastric pH phase with either evidence of alkalinization and no further reflux episodes or loss of communication with the Bravo capsule prior to the end of the 48-h data collection period. Of the 100 patients reviewed, 11% manifested evidence of early passage of the Bravo capsule resulting in a misinterpretation of the data as abnormal acid exposure. The mean time of inaccurate data after transit of the Bravo capsule was 18 h and 42 min. The mean length of time that the capsule was retained in the stomach prior to duodenal passage was 4 h. If the aforementioned data were included in the final interpretation of the study, it yielded a mean DeMeester score of 44.25 with a mean total time of pH <4 of 14.7% per case. Exclusion of the prolonged gastric phase from the final interpretation of each case resulted in a statistically significant reduction in the mean total time the pH <4 (4.33 vs. 14.7%, p < 0.05) and the mean DeMeester score (12.81 vs. 44.25 p < 0.05). The mean time from the initiation of esophageal pH data to the passage of the Bravo capsule into the stomach was 15 h and 22 min. The observation mandates meticulous inspection of the pH tracing by the interpreting physician throughout the entirety of a 48-h study to identify premature transit of the capsule. Tracings that show prolonged acid exposure or loss of communication with the Bravo capsule should be screened for the capsule's possible early dislodgement and premature advancement into the stomach.

Gastro-oesophageal reflux disease in chronic laryngitis: prevalence and response to acid-suppressive therapy

BACKGROUND

Gastro-oesophageal reflux is thought to cause chronic laryngitis through laryngopharyngeal reflux. Response of laryngitis to treatment with acid-suppressive therapy supports this causal link.

AIM

To determine the prevalence of gastro-oesophageal reflux disease in patients with chronic laryngitis and response to proton-pump inhibitor therapy.

METHODS

Patients with chronic laryngitis were recruited. The frequency and severity of reflux and laryngeal symptoms were scored and laryngitis graded by laryngoscopy. All patients underwent esophagogastroduodenoscopy and 24-h ambulatory pH monitoring before receiving lansoprazole 30 mg b.d. for 8 weeks.

RESULTS

The prevalence of gastro-oesophageal reflux disease was 65.6% (21 of 32). Based on positive pH test, the prevalence was 25% (eight of 32). The change in laryngeal symptom score and laryngitis grade was significantly higher in GERD compared with non-GERD patients (P = 0.010 for both). The proportion of patients with marked/moderate improvement in laryngeal symptoms were significantly higher in patients with reflux (14 of 21, 67%) compared to those without reflux (two of 11, 18%; P = 0.026).

CONCLUSIONS

The prevalence of gastro-oesophageal reflux disease amongst our patients with chronic laryngitis was high. The response to treatment with proton-pump inhibitors in patients with reflux disease compared to those without underlined the critical role of acid reflux in a subset of patients with chronic laryngitis.

Safety and tolerability of transoral Bravo capsule placement after transnasal manometry using a validated conversion factor

OBJECTIVES

To prospectively calculate and validate a conversion factor in healthy volunteers that allows accurate nonsedated, transoral (TO) Bravo capsule placement after transnasal (TN) manometry, and to evaluate the ease and safety of nonendoscopic Bravo placement compared with endoscopic placement.

METHODS

Part 1. Twenty-five healthy volunteers underwent sequential TN and TO esophageal manometry to measure the distance to the lower esophageal sphincter (LES). A TN to TO conversion factor was calculated from these measurements. Part 2. Twenty volunteers underwent TN manometry followed by unsedated TO Bravo capsule placement using the conversion factor calculated in part 1. TN endoscopy then measured the location of the Bravo capsule in relationship to the squamocolumnar junction (SCJ). Part 3. During an 18-month period, 370 consecutive patients referred for a Bravo procedure underwent nonendoscopic, unsedated TO placement (308 patients) or standard endoscopically assisted placement (62 patients).

RESULTS

Part 1. All 25 volunteers completed TN and TO manometry; a conversion factor of 4 cm was calculated. Part 2. Using the calculated conversion factor of 4 cm, a Bravo capsule was deployed TO 5 cm above the proximal border of the LES. The mean +/- standard deviation (SD) TN endoscopic distance to the capsule was 6.0 cm (+/-0.3 cm) above the SCJ. Part 3. A total of 333 patients completed the entire study (90%). Analysis of 48-h pH measurements did not reveal any significant differences between the two groups.

CONCLUSIONS

A reliable and valid conversion factor of 4 cm following TN manometry permits accurate TO placement of the Bravo capsule without endoscopy. TO, unsedated Bravo placement is safe, well tolerated, and may minimize costs and potential risks associated with endoscopy.

Discovery of a New Class of Macrocyclic Antagonists to the Human Motilin Receptor

A novel class of macrocyclic peptidomimetics was identified and optimized as potent antagonists to the human motilin receptor (hMOT-R). Well-defined structure-activity relationships allowed for rapid optimization of potency that eventually led to high affinity antagonists to hMOT-R. Potency and antagonist functional activity were confirmed both in functional and cell-based assays, as well as on isolated rabbit intestinal smooth muscle strips. Rapid access to this novel class of macrocyclic target structures was made possible through two efficient and complementary solid-phase parallel synthetic approaches, both of which are reported herein.

Endoscopic removal of the wireless pH monitoring capsule in patients with severe discomfort

BACKGROUND

Few patients have significant symptoms during wireless esophageal pH monitoring, and the capsule typically sloughs spontaneously. Severe discomfort during monitoring can occur that requires endoscopic dislodgement of the capsule.

OBJECTIVE

To determine the frequency with which endoscopic capsule dislodgement is required and the outcomes of the intervention.

DESIGN

Chart review.

SETTING

University-based outpatient endoscopy facility.

PATIENTS

A total of 452 consecutive patients undergoing wireless pH monitoring over a 3.5-year period.

INTERVENTIONS

Endoscopic dislodgement of the capsule by using nudging with the endoscope tip and cold snare techniques.

RESULTS

Eight subjects (1.8%) required endoscopic capsule dislodgement because of severe chest pain or odynophagia (n = 7) or severe foreign-body sensation (n = 1). Chest pain was the initial indication for pH monitoring in 5 (62.5%) of the subjects. Initial nudging with the endoscope tip successfully dislodged 2 capsules; continued nudging produced mucosal stripping in 3 subjects, which required hemostasis in 1. A cold snare was used successfully, without complication, to separate the capsule from stripped mucosa and as a primary removal method in the remainder of subjects. Capsule removal uniformly resulted in marked improvement of discomfort.

CONCLUSIONS

Endoscopic removal of the capsule was required in <2% of subjects who underwent wireless pH monitoring. Separation of the capsule from the mucosa with a cold snare may be the preferred method of accomplishing uncomplicated removal.

Wireless pH monitoring in patients with non-cardiac chest pain

OBJECTIVES

Gastroesophageal reflux disease (GERD) is an important cause of non-cardiac chest pain (NCCP), and its detection can require ambulatory pH monitoring. The purpose of this study was to determine the advantages of a wireless ambulatory pH monitoring system and 2 days of recording in diagnosing GERD in NCCP patients.

METHODS

Results from ambulatory pH studies using the BRAVO capsule were reviewed from 62 subjects referred for evaluation of NCCP after non-diagnostic response to proton pump inhibitor therapy. Acid exposure time (AET) and symptom-reflux association tests were calculated after 1 day of recording and compared to the final outcome from the 2-day study.

RESULTS

Extending the recording time increased the number of subjects having elevated AET from 16 after 1 day to 22 after 2 days of recording, a 9.7% gain in subjects (95% CI 4.6-19.6%). The number of chest pain episodes doubled from 1 to 2 days, and 4 subjects (7.3%) developed symptoms only on the second day of monitoring. Statistically significant reflux-symptom association probabilities surfaced in an additional 13 subjects (21.0%; 95% CI 12.7-32.7%) by the conclusion of the 2-day study. The effect primarily was to identify significant associations in patients with lower proportions of reflux-associated symptoms. Taken together, 19.4% (95% CI 11.5-30.9%) of the subject group gained meaningful information suggesting a reflux diagnosis by extending the pH monitoring time to 2 days.

CONCLUSIONS

Extending monitoring to 2 days with a wireless pH monitoring system increases the detection of GERD in a clinically significant proportion of patients with NCCP.

Performance, tolerability, and symptoms related to prolonged pH monitoring using the Bravo system in Mexico

BACKGROUND

The traditional system for esophageal 24-h pH monitoring requires transnasal introduction of the catheter with pH sensors; this technique produces discomfort, inconvenience, and interference with daily activity. Recently, a catheter-free pH monitoring system (Bravo) has been proposed as an alternative and promising method for 24-h pH.

AIM

To evaluate performance, tolerability, and symptoms related to this new technology in our population.

METHODS

Consecutive patients with gastroesophageal reflux disease (GERD) with indication for 24-h pH were included. pH Bravo capsule was placed 6 cm above the squamocolumnar junction using endoscopic measurement. Symptoms associated were evaluated daily in a personal diary until 7 days after the capsule attachment. Severity of symptoms was assessed by a 5-point Likert scale. Capsule detachment was assessed by chest X-ray.

RESULTS

Eighty-four patients were included. Forty-nine were female (mean age 44 +/- 12 yr). Indications for pH monitoring were: nonresponse to proton pump inhibitor therapy in 38 (45%), preoperative evaluation for anti-reflux surgery in 36 (43%), previous failed transnasal 24-h pH monitoring in 6 (7%), and extra-esophageal manifestations of GERD in 4 (5%). The capsule was successfully attached in 95% of patients. At day 7, capsule detachment occurred spontaneously in all cases. Symptoms related to capsule attachment were: chest pain in 26 (33%), foreign body sensation in 11 (14%), nausea in 5 (6%), and 9 (11%) patients had more than one symptom. Severities of those symptoms were mild, and no patient required removal of the capsule. Women and younger patients had more symptoms related to the procedure (p < 0.05).

CONCLUSIONS

Esophageal pH monitoring with Bravo capsule is a safe, reliable, and tolerable method in patients with GERD.

Diagnosis and treatment of noncardiac chest pain

Chest pain is common: one in four of the population have an episode annually. Of those who present to hospital, nearly two-thirds have noncardiac chest pain. More than half of these cases might have gastroesophageal reflux disease. Opinion differs over what is the most appropriate application of current investigatory methods. Evidence suggests that, once cardiac disease is ruled unlikely, empiric use of a proton pump inhibitor is an option; if acid suppression fails, detailed investigations as clinically indicated can be considered. A range of esophageal investigations is available, including 24-hour or 48-hour esophageal pH testing and esophageal manometry, as well as provocative tests, but there is no consensus as to which methods are the most useful. Psychiatric evaluation is not routine, but psychiatric or psychological disorders are common. Musculoskeletal disorders are also common, but are frequently overlooked. It is possible to subject patients to a comprehensive set of investigations before empiric therapy, but recent studies have failed to demonstrate an improved outcome using this exhaustive approach. A new tactic is required, with less attention spent on absolute diagnostic accuracy and more emphasis on optimizing the long-term clinical outcome in patients with noncardiac chest pain. It is possible that the targeted use of multiple drug trials in a policy of 'therapy as investigation' might be a superior methodology.