The role of esophageal pH monitoring in symptomatic patients on PPI therapy

BACKGROUND: Ambulatory pH monitoring while on therapy is often recommended in gastroesophageal reflux disease (GERD) patients with continued symptoms. However, to date, little data exist to justify this indication. AIM: To assess the role of pH monitoring in symptomatic patients despite aggressive therapy with typical or extra esophageal GERD. METHODS: Retrospective review of 2,291 ambulatory pH tracings (1999-2003) identified subgroup of studies performed on proton pump inhibitor (PPI) therapy. Patients with prior fundoplication or Barrett's esophagus were excluded. Patients grouped on predominant presenting GERD symptoms: typical (heartburn and regurgitation) or extra esophageal (chest pain, cough, hoarseness, sore throat, shortness of breath, asthma). The distribution of abnormal pH parameters in each group calculated and univariate analyses assessed the probability of abnormal pH in each group. Abnormal cutoff values traditionally used in clinical practice and more stringent cutoff values used to determine distribution of abnormality as a function of cutoff values. RESULTS: A total of 250 patients (mean age 54.3 yrs, 59% female) underwent pH monitoring on either daily (b.i.d.) or twice daily (q.d.) on PPI therapy: 115 (46%) with extra esophageal and 135 (54%) with typical GERD symptoms. Extra esophageal GERD patients were more likely to undergo pH monitoring on b.i.d. PPIs (OR = 2.7; 95% CI = 1.6-4.4; p < 0.01). 52 (93%) of typical and 74 (99%) of extra esophageal GERD patients on b.i.d. PPIs tested normal. The odds of a normal pH values were 11 times higher for patients on b.i.d. PPIs (OR = 11.4; 95% CI = 4.3-30.1, p < 0.01) than those on q.d. PPIs. CONCLUSIONS: 1) The likelihood of an abnormal esophageal pH for symptomatic GERD patients on b.i.d. PPI is very small. 2) In this group of patients failing b.i.d. PPIs causes other than GERD should be sought.     

Esophageal pH testing in patients refractory to proton pump inhibitor therapy.

BACKGROUND: Proton pump inhibitors (PPIs) are the most potent drugs available for the management of gastroesophageal reflux disease (GERD). Ambulatory 24 h pH monitoring is often recommended for patients experiencing symptoms despite PPI therapy. Recent pivotal data suggest that pH studies are predictably normal in this setting, casting doubt on the clinical utility of the current practice. OBJECTIVE: To describe 24 h pH findings in patients referred by gastrointestinal specialists for the indication of GERD refractory to PPI therapy. METHODS: A retrospective review was performed, examining all patients undergoing ambulatory esophageal pH monitoring at the St Boniface General Hospital Motility Laboratory, between January 2002 and June 2005. Tests performed in patients clinically suspected of having GERD who were not responding to PPI therapy formed the study group. pH data were analyzed for the total, upright and supine periods. Abnormal reflux parameters were defined by applying three criteria: DeMeester score greater than 14.72; pH less than 4.0 more than 5.5% of the total time, more than 8.3% of the time upright or more than 3% of the time in the supine position; and pH less than 4.0 for more than 1.6% of the total time. RESULTS: A total of 417 patients underwent pH monitoring during the time of the review. One hundred seven patients (mean age 51.7 years; 37 men and 70 women) met study criteria. Sixty-eight (63.6%) were referred by a gastroenterologist and 39 (36.4%) were referred by a gastroenterologist surgeon. Sixty-one patients were on twice-daily PPIs and 46 were on once-daily dosing. Using the most stringent pH criteria, namely criteria 2, pH readings were abnormal in 30% of patients on once-daily PPIs and in 25% of patients on twice-daily dosing. The prevalence of abnormal pH readings were even higher if criteria 1 or 3 were applied. CONCLUSIONS: In a patient population assessed by a specialist as having clinically suspected GERD that is not responding to PPI therapy, a substantial number of patients will have abnormal esophageal pH test results. The role of pH testing in the algorithm of GERD is evolving; however, our data suggests that an abandonment of pH testing is premature.     

Four-day Bravo pH capsule monitoring with and without proton pump inhibitor therapy.

BACKGROUND & AIMS: Ambulatory pH testing often is used to guide the management of reflux symptoms that do not respond to proton pump inhibitor (PPI) therapy and to evaluate the contribution of acid reflux to atypical symptoms. Controversy exists as to whether such clinical studies are performed optimally off or on PPI therapy. The aim of the present study was to determine the feasibility of 4-day pH recordings using a pH system that would encompass time periods both before and during PPI therapy. METHODS: Eighteen patients underwent 4-day ambulatory pH testing using 2 separate receivers calibrated to a single Bravo pH capsule. Rabeprazole was administered on days 2-4 of the study (20 mg orally twice a day). RESULTS: Indications for pH testing were refractory heartburn, chest pain, or chronic cough. pH recordings showed that 9 patients (53%) had esophageal acid exposure values that exceeded 4% on day 1 and 7 patients (41%) had values that exceeded 5.3%. Patients showed significant and progressive reductions in acid exposure on days 2-4 of the recording period. Of the 7 patients with quantitatively abnormal levels of acid exposure on day 1, 86% had normalization by day 3. CONCLUSIONS: Prolonged, esophageal pH recordings using the Bravo pH system are feasible and allow for combined testing both off and on a therapeutic trial of PPI. Such studies may allow for the acquisition of complementary information in a single test that may be useful in the management of patients with suspected gastroesophageal reflux disease symptoms.     

Acid reflux detection and symptom-reflux association using 4-day wireless pH recording combining 48-hour periods off and on PPI therapy

OBJECTIVES: Studies have shown that extended pH recording improves the sensitivity of esophageal pH monitoring. Controversy exists as to whether pH studies are optimally done off or on proton pump inhibitor (PPI) therapy. The aim of this study was to incorporate periods both off and on PPI therapy in a single, extended pH test and describe the effect of PPI therapy on symptom-reflux associations.
METHODS: Sixty patients underwent 4-day pH recordings using two separate receivers calibrated to a single wireless pH capsule. Patients were off PPI therapy for days 1 and 2. Either rabeprazole 20 mg twice daily or omeprazole/sodium bicarbonate 40 mg twice daily were administered on days 3 and 4. Symptom-reflux correlation was determined by the symptom index (SI), symptom sensitivity index (SSI), and symptom association probability (SAP).
RESULTS: Twenty studies were excluded due to premature detachment (9) or incomplete data capture for >6 of the 96-h period (11). Off therapy, 14 patients (35%) had abnormal esophageal acid exposure values. On day 4, 39 patients (98%) had normal acid exposure. The number of symptoms and acid reflux events were significantly higher off PPI therapy. Furthermore, the percentage of patients with a positive SI fell from 50% off PPI to 9% on PPI ( P < 0.01), whereas 63% of patients symptomatic off PPI therapy became asymptomatic on PPI therapy and could not have an SI calculated. Similarly, the SAP was abnormal in 45% of patients off PPI therapy but only 10% on PPI therapy ( P < 0.01).
CONCLUSIONS: Extended pH recording improves the detection of abnormal acid reflux and increases the number of recorded symptoms and acid reflux events. Combined off and on PPI therapy pH testing enhances the interpretation of pH monitoring and symptom-reflux correlations, which can be helpful in the management of patients with PPI-unresponsive gastroesophageal acid reflux symptoms.     

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.     

Wireless esophageal pH monitoring: new technique means new questions

INTRODUCTION: The introduction of wireless pH monitoring has been touted as a significant advance in the diagnosis of gastroesophageal reflux and associated disorders. We prospectively enrolled patients in a research registry to assess the feasibility and safety in clinical use. METHODS: All patients undergoing endoscopy with wireless pH studies (Medtronic Bravo pH system) for a 12-month period starting in April 2004 were prospectively enrolled. Probes were placed 6 cm above the endoscopically localized squamocolumnar junction. Successful completion was defined as at least 24 hours of pH recording. Safety data were obtained by review of patient diaries. All results are given as median with 25% to 75% confidence interval (CI). RESULTS: A total of 217 studies with endoscopy and capsule placement were performed (65% women; median age, 51 years; range, 42-58 years) and included in the study; 1 patient refused participation in the registry and 5 studies were performed without preceding endoscopy and were excluded from this analysis. The pH study was successfully completed in 95.1%; early capsule detachment (1 hours; CI, 0-5 hours) or receiver malfunction occurred in 7 and 2 cases, respectively. There were no immediate adverse effects; 18 patients (9%) complained about significant chest discomfort, associated with odyno- or dysphagia, requiring removal of the capsule in 3 patients (1.5%). Of the completed studies, 56% were abnormal with 32.2% being abnormal on both days, whereas 16.1% and 6.9% only showed increased acid exposure on day 1 or 2, respectively. The higher likelihood of abnormal results for day 1 was associated with a significantly increased esophageal acid exposure during the first 6 hours after capsule insertion on day 1 (total time with pH < 4: 6.9%; CI, 3.2%-16.5%) compared with the corresponding time on day 2 (5.0%; CI, 0.9%-10.8%; P < 0.01), without differences esophageal acidification during the remaining time or differences in recorded activity. CONCLUSIONS: Using a large registry of patients with suspected gastroesophageal reflux symptoms, our data show that wireless pH studies can be safely completed in more than 90% of patients. Whereas variability during prolonged recordings should be expected, the significantly higher likelihood of abnormal findings during the initial period of pH monitoring suggests a systematic influence of endoscopy and associated premedication, typically performed prior to capsule insertion, which needs to be considered when pH data are analyzed.     

Diagnostic options for patients with refractory GERD

Patients with refractory gastroesophageal reflux disease (GERD) are those who have persistent symptoms while being treated with proton pump inhibitors (PPIs). One third of GERD patients requiring a daily PPI are estimated to eventually experience treatment failure. These patients are usually referred for further investigation to confirm the presence of GERD or to identify other entities as the cause of symptoms. Tools that can be used in this diagnostic process include upper gastrointestinal endoscopy with analysis of esophageal biopsies, esophageal pH monitoring, impedance-pH monitoring, and esophageal bilirubin monitoring. The conventional diagnostic approach includes upper gastrointestinal endoscopy and ambulatory pH monitoring while receiving PPI therapy. New diagnostic techniques that may be useful with refractory GERD include impedance-pH monitoring, which is very sensitive in detecting persistent weakly acidic reflux, and bilirubin monitoring, which detects increased esophageal exposure to bile. Gastric pH monitoring should be reserved for patients in whom PPI resistance is suspected.     

Reflux monitoring: on or off therapy?

The role of esophageal pH (or impedance) monitoring in diagnosing gastroesophageal reflux disease (GERD) has evolved over the years. In the era of empiric therapy with potent acid-suppressive agents such as proton pump inhibitors (PPIs), esophageal reflux monitoring is often reserved for patients with PPI-refractory symptoms (1, 2). Given the complexity of patient presentations, technological advancement, and emerging data in the field of GERD, two essential questions need to be addressed: (i) What are the indications for esophageal pH testing in patients suspected to have GERD? (ii) If patients do not respond to aggressive acid suppression, what is the likelihood that they still have reflux; and should the testing be performed at baseline (i.e., off therapy), or is it more important to know whether there is continued reflux despite therapy (i.e., on therapy)?     

Characteristics and clinical relevance of proximal esophageal pH monitoring

OBJECTIVE: It is well established that various ENT disorders and symptoms may be a manifestation of gastroesophageal reflux disease (GERD). Measuring proximal esophageal acid exposure might be useful in the evaluation of patients with suspected reflux-related ENT manifestations, but the limited available data are conflicting. The aim of the present study was to study the determinants of proximal esophageal acid exposure (PR) and to evaluate the clinical usefulness of ambulatory proximal pH monitoring. METHODS: Twenty healthy controls and 346 patients with suspected reflux disease underwent typical and atypical GERD symptom assessment, endoscopy, esophageal manometry and ambulatory combined dual esophageal pH, and Bilitec duodeno-gastro-esophageal reflux exposure (DGER) monitoring. The presence of pathological PR and its relation to symptom pattern and distal esophageal acid exposure (DR) and DGER exposure were analyzed. RESULTS: Fifty-seven patients (16%) had pathological PR. Demographic characteristics, symptom pattern, and manometric findings did not differ in patients with normal or pathological PR. Patients with pathological PR had significantly higher DR and DGER. The multivariate analysis identified only pathological DR as an independent risk factor for the presence of pathological PR (odds ratio 4.515, 95% CI 2.48-8.23, p < 0.0001). Only 20 patients (6%) had pathological proximal reflux without pathological distal acid reflux. CONCLUSION: The findings of the present article do not support routine proximal esophageal pH monitoring as a clinical tool: PR does not differentiate patients with typical or atypical GERD manifestations and depends mainly on DR.     

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.     

Prevalence of gastroesophageal reflux in difficult asthma: relationship to asthma outcome

STUDY OBJECTIVES: To determine the prevalence of gastroesophageal reflux disease (GERD)-both symptoms and objective evidence-using 24-h dual-probe pH monitoring in difficult asthma, and the relationship between the presence and treatment of GERD to clinical outcome. DESIGN AND SETTING: As part of a systematic evaluation protocol, 68 subjects with difficult-to-control asthma attending a difficult asthma clinic were referred for dual-probe ambulatory pH esophageal monitoring. RESULTS: Esophageal probe data were available in 52 patients (76%) with difficult asthma. The prevalence of GERD/GERD-associated asthma symptoms was 75% (39 of 52 patients; 95% confidence interval [CI], 63 to 84.7%). The prevalence of GERD as evidenced by an abnormal pH profile at the distal esophageal probe was 55% (29 of 52 patients; 95% CI, 40 to 69%). The prevalence of GERD at the proximal probe was 34.6% (18 of 52 patients; 95% CI, 23.6 to 51%). The prevalence of GERD was similar in asthmatic subjects who responded to intervention and those who remained difficult to control (therapy resistant). Asymptomatic GERD was present in 9.6% (5 of 52 patients); 16% of cough episodes correlated with acid reflux. CONCLUSIONS: In difficult-to-control asthma, GERD is common, but identification and treatment of GERD do not appear to relate to improvement in asthma control in this population.     

Acid and bile reflux in erosive reflux disease, non-erosive reflux disease and Barrett's esophagus

BACKGROUND/AIMS: Gastroesophageal reflux disease (GERD) may occur with acid, bile or in a mixed form. Endoscopic injury and mucosal metaplasia are a known sequlae to pathological GERD. The aim of the study was to determine the contribution of acid and duodenogastroesophageal reflux (DGER) to endoscopic severity in patients with GERD and Barrett's esophagus. METHODS: Ninety-one patients complaining of reflux symptoms were studied with upper gastrointestinal endoscopy and graded to non-erosive reflux disease (NERD), erosive reflux disease (ERD) and Barrett's esophagus (BE). Esophageal manometry and simultaneous ambulatory 24-h esophageal pH and bilirubin monitoring (Bilitec 2000) were done to all patients. RESULTS: Seventy one patients (78.0%) had ERD (Savary-Miller (grade I-III), 11 patients (12.1%) had NERD and 9 patients (9.9%) had BE suspected endoscopically and diagnosed by histological esophageal biopsy. Combined 24-h esophageal bilirubin and pH monitoring revealed that 39 patients (42.9%) had mixed acid and bile reflux, 16 (17.6%) had pathological acid reflux only, 18 (19.8%) had bile reflux only and 18 patients (19.8%) had no evidence of abnormal reflux. The percentage of the total time of bilirubin absorbance above 0.14, in 71 patients with ERD was (8.18 +/- 11.28%), and in 9 patients with BE was (15.48 +/- 30.48%) which was significantly greater than that in 11 patients with NERD (4.48 +/- 8.99%), p < 0.05 and p = 0.01 respectively. All BE patients had abnormal esophageal bile reflux (3 bile alone and 6 mixed bile and acid); 44 of 71 patients (61.97%) with ERD had abnormal esophageal bile reflux (13 bile alone and 31 mixed bile and acid); meanwhile 15 of them (21.2%) had abnormal acid exposure alone. Of the 11 patients with NERD, 4 patients (36.4%) had abnormal esophageal bile reflux, 2 of them mixed with acid. CONCLUSIONS: The Bilitec method reliably identifies the presence of bilirubin and quantitatively detects duodenogastroesophageal reflux of bile. Mixed reflux (acid and bile) is the chief pattern of reflux in GERD patients in this study. Bile reflux either alone or mixed with acid reflux contributes to the severity of erosive and non-erosive reflux disease as well as to Barrett's esophagus.     

High prevalence of proximal and distal gastroesophageal reflux disease in advanced COPD

BACKGROUND: Gastroesophageal reflux disease (GERD) is common in a variety of chronic respiratory diseases, but little is known about GERD in the setting of COPD. The aims of this study were to determine the prevalence, presentation, and predictors of GERD based on proximal and distal esophageal pH monitoring in patients with severe COPD. METHODS: Forty-one COPD patients with a mean FEV1 of 24% of predicted underwent dual-probe 24-h esophageal pH monitoring, and 1 patient underwent esophagogastroduodenoscopy. RESULTS: The prevalence of GERD was 57%. Elevated distal and proximal reflux were present in 41% and 46% of patients undergoing esophageal pH studies, respectively. Fifteen percent of these patients had abnormal proximal reflux despite having normal distal probe results. Most patients with GERD were not receiving acid blockers at the time of their referral, and only one third reported heartburn and/or acid regurgitation during the pH study. Only higher body mass index was predictive of reflux on regression analysis (odds ratio, 1.2; 95% confidence interval, 1.0 to 1.5; p = 0.05). CONCLUSIONS: GERD is common in advanced COPD. Patients are often asymptomatic and have a relatively high prevalence of isolated abnormal proximal reflux. Dual-probe monitoring is therefore well suited for detecting GERD in patients with advanced COPD.     

Yield of 24-Hour Esophageal pH and Bilitec Monitoring in Patients with Persisting Symptoms on PPI Therapy

Current management algorithms propose pH monitoring under proton pump inhibitors (PPIs) in suspected gastroesophageal reflux disease (GERD) with insufficient treatment response, but recent observations challenge this approach because of its low yield. AIM: To perform an audit of the outcomes of pH monitoring under PPI therapy in our unit, and to study the yield of additional nonacid reflux monitoring. METHODS: All pH monitoring studies under antireflux therapy since 1997, with or without simultaneous Bilitec monitoring, were analyzed. RESULTS: From 1997 to 2003, 347 patients (157 men, mean age 49.4 +/- 0.8 years) underwent pH studies on PPI therapy (28% half-, 67% full-, and 5% double-dose PPI) for persisting typical (53%) or atypical (75%) symptoms. In 184 patients, simultaneous Bilitec monitoring was performed. Esophageal pH monitoring on PPI was pathological in 105 (30%) patients. Pathological pH monitoring on PPI was associated with typical reflux symptoms (64 versus 52%, P = 0.03), and a higher prevalence of persisting esophagitis (54 versus 36%, P < 0.005) and of hiatal hernia (58 versus 27%, P < 0.005). Bilitec monitoring on PPI therapy was pathological in 114 (62%) patients, of which 74 (40%) had normal pH monitoring. Adding Bilitec increased the rate of abnormal results over pH monitoring alone, from 38% to 69% on half-dose, from 27% to 69% on full-dose, and from 0% to 38% on double-dose PPI. CONCLUSIONS: The rate of abnormal pH monitoring in symptomatic GERD patients while on PPI therapy is relatively low, especially in those on double-dose PPI. Combined pH and Bilitec monitoring significantly increased the rate of ongoing pathological reflux compared to pH alone in refractory to PPI therapy GERD patients.     

正常人和胃食管反流病人的昼夜食管pH和动力变化

目的:为探讨正常人和胃食管反流病(gastroesophageal reflux disease,GERD)病人昼夜食管运动规律以及食管运动与酸反流的关系。方法:45例GERD病人和10名正常人均接受食管测压和动态食管pH及压力同步监测。结果:(1)下食管括约肌压、远端食管蠕动压及有效食管蠕动百分比在酸反流DeMeester高计分组明显低于低计分组(P<0.05),在反流性食管炎组也明显低于非反流性食管炎组(P<0.05)。(2)有GERD症状或食管炎的卧位有效蠕动百分比明显低于立位(P<0.05)。反流性食管炎组80％有夜间或伴有夜间反流,而不伴反流性食管炎的GERD无1例出现夜间反流。结论:昼夜食管pH和压力动态监测有利于进一步探讨GERD的运动病理,除LES功能外,食管清除功能在GERD发病中起重要作用。     

Belching: dyspepsia or gastroesophageal reflux disease?

OBJECTIVES: Eructation (belching) is a common symptom seen in clinical practice. Because either belching or heartburn may result from transient lower esophageal sphincter relaxations, it has been proposed that belching may be a manifestation of gastroesophageal reflux disease (GERD). In this retrospective study we evaluated the prevalence of belching in dyspepsia and GERD and the relation of belching to acid reflux events documented by pH monitoring. METHODS: We examined the prevalence, frequency, and severity of belching and other GERD symptoms by use of standardized questionnaires in 180 GERD patients (group A) and 78 dyspeptic controls (group B) referred for evaluation at our institution. GERD was defined as either endoscopic esophagitis (or Barrett's esophagus) or positive DeMeester score (>14.2) on pH monitoring or both. Dyspeptic patients had normal endoscopy and pH studies. We also analyzed the relationship of belching to acid reflux events during the 24-h period of pH studies. RESULTS: Of 180 GERD patients, 132 (70%) reported belching during pH monitoring, versus 63 of 78 dyspeptic patients (80%) (p = ns). Similarly, 163 of 180 GERD patients (90%) reported heartburn versus 64 of 78 of dyspeptic patients (82%) (p = ns). Review of symptom questionnaires revealed no significant difference in belching severity between groups. However, heartburn and acid regurgitation were significantly more severe among GERD patients. There was a significantly higher correlation of both heartburn and belching with acid events in patients with GERD compared with patients with dyspepsia. In addition, although both belching and heartburn were significantly improved in patients with GERD, belching scores remained unchanged after proton pump inhibitor (PPI) therapy in patients with dyspepsia. CONCLUSIONS: Belching is as common and as severe in patients with dyspepsia as it is in patients with GERD. Belching and heartburn in GERD patients are more likely correlated with episodes of pathological acid reflux. Because belching cannot be clinically used as a discriminatory symptom, ambulatory pH monitoring should be considered to elucidate the relationship of belching to acid reflux in patients with dyspepsia or GERD.     

Utility of ambulatory 24-hour esophageal pH and motility monitoring in noncardiac chest pain: report of 90 patients and review of the literature

It is unclear whether prolonged motility monitoring improves the diagnostic yield of standard esophageal tests in patients with noncardiac chest pain. Our aim was to assess the diagnostic value of ambulatory 24-hr pH and pressure monitoring in patients with noncardiac chest pain. Stationary manometry, edrophonium testing, and ambulatory pH and motility studies were performed in 90 consecutive patients with recurrent chest pain and normal coronary angiograms. Normality limits of ambulatory 24-hr motility were established in 30 healthy controls. The diagnoses of specific esophageal motility disorders (nutcracker esophagus and diffuse esophageal spasm) by stationary and ambulatory manometry were discordant in 48% of the patients. Edrophonium testing was positive in 9 patients, but correlated poorly with esophageal diagnoses. During ambulatory studies, 144 chest pain events occurred in 42 patients, and 72 (50%) were related to esophageal dysfunction. Strict temporal associations of events with esophageal dysfunction in relation to ambulatory 24-hr pH'motility scores permitted four patient categorizations: true positives (event-related and abnormal tests), N = 15; true negatives (event-unrelated and abnormal tests), N = 10; reduced esophageal pain threshold (event-related and normal tests), N = 4; and indeterminate origin (event-unrelated and normal tests), N = 13. Overall, 19 patients (21%) had a probable esophageal cause for chest pain (14 esophageal motility disorder, 4 acid reflux, 1 both). In conclusion, ambulatory manometry increases the diagnostic yield of standard esophageal testing in noncardiac chest pain, but the gain is small. Causes of chest pain other than high esophageal pressures and acid reflux must still be sought in most patients with chest pain of unknown origin after a negative cardiac work-up.     

REVIEW: Ambulatory Esophageal pH Monitoring: Technique, Interpretations, and Clinical Indications

Gastroesophageal reflux disease (GERD) is the most common esophageal disorder and perhaps among the most prevalent conditions seen in the primary care setting. The clinical manifestations of GERD, typical or atypical, such as noncardiac chest pain, respiratory or ear, nose, and throat symptoms, result from the reflux of gastric contents into the esophagus. Thus the clinical spectrum is wide and requires accurate diagnosis. Ambulatory 24-hr esophageal pH monitoring is not useful in all patients suspected to have GERD. This review describes the technique of ambulatory 24-hr esophageal pH monitoring, the interpretation of findings, and clinical applications of this test.     

Dual-Channel Ambulatory Esophageal pH Monitoring (A Useful Diagnostic Tool?)

Ambulatory pH monitoring of the distal esophagusis the most accurate diagnostic study for patients withsuspected gastroesophageal reflux disease (GERD). Themeasurement of proximal esophageal acid exposure time may be useful in patients with atypicalreflux symptoms. The aim of this study is to evaluate ifproximal esophageal pH monitoring provides usefulinformation beyond that learned with distal esophageal pH monitoring. We routinely performeddual-channel pH monitoring with pH electrodes positionedat 20 and 5 cm above the manometric lower esophagealsphincter from January 1992 to August 1995. All patients scored their esophageal symptoms from zero(none) to four (severe). We compared proximal esophagealreflux (PR) in patients with typical symptoms (i.e.,heartburn, regurgitation) and in patients with atypical symptoms (i.e., chest pain, cough, hoarseness,and asthma). We compared symptom profiles betweenpatients with and without PR. We reviewed our experiencein patients with abnormal PR, but with a normal amount of distal esophageal reflux (DR). We studied441 consecutive patients. There were no significantdifferences in PR between patients with typical andatypical symptoms. There were no differences in symptom profiles between patients with normal andabnormal PR. There were no differences of PR between thedifferent atypical symptoms. PR did not correlate withthe severity of the patient's symptoms. PR correlated well only with DR. Twenty-four patients hadisolated abnormal PR, but only six patients improvedwith antireflux therapy. We conclude that routineambulatory esophageal pH monitoring of the proximalesophagus appears to be of little value. The decision tooffer patients an empiric trial of antireflux therapyfor suspected GERD should not be based on the presenceor absence of PR.     

Diagnostic approach to gastro-oesophageal reflux disease

It is neither practical nor necessary to embark on a diagnostic evaluation of every patient with classic symptoms of gastroesophageal reflux disease (GERD). In most cases a well-taken history is usually sufficient to confirm the diagnosis of GERD and begin therapy. However, some patients may present with atypical symptoms; and many with classic symptoms are refractory to standard medical therapy. In these cases one must rely on diagnostic studies to confirm that abnormal acid reflux is present and potentially responsible for the symptoms in question. Modern technology has given us many different modalities to quantify esophageal acid exposure and determine whether symptoms are correlated to reflux events. Unfortunately, these studies are not perfect and the work-up of refractory patients typically requires more than one test. The goal of the following review will be to summarize the currently available techniques for diagnosis of GERD and also discuss the possible impact of new techniques, such as intraluminal impedance monitoring and wireless ambulatory pH monitoring.