Factors predictive of gastroesophageal reflux disease and esophageal motility disorders in patients with non-cardiac chest pain

Background: Patients with non-cardiac chest pain (NCCP) are referred for esophageal motility testing and pH monitoring since gastroesophageal reflux disease (GERD) and esophageal motility disorders are frequently encountered in these patients. Our aim was to determine the prevalence and distribution of these disorders and to identify predictors of abnormal esophageal function testing.

Methods: We performed a retrospective study of NCCP patients who presented after a negative cardiac evaluation and underwent esophageal manometry, esophageal pH monitoring and upper endoscopy from January 2010 to January 2017.

Key results: In a total of 177 patients, esophageal motility disorders were diagnosed in 31% and GERD in 35% of the patients. The most common diagnoses were ineffective esophageal motility (IEM) in 14.1%, jackhammer esophagus in 6.8%, diffuse esophageal spasm in 5.1% and achalasia in 2.3% patients. Older age [for every 5-year increment, odds ratio (OR) 1.2 (95% confidence intervals (CI) 1.00–1.3) p?=?.047] and dysphagia [OR 3.8 (95% CI, 1.9–7.5) p?p?=?.032] was predictive of GERD. Abnormal esophageal testing was associated with male gender [OR 2.2 (95% CI, 1.04–4.6) p?=?.039], older age [for every 5-year increment, OR 1.2 (95% CI, 1.03–1.3) p?=?.016] and Caucasian race [OR 3.1 (95% CI, 1.1–8.7) p?Conclusions: Approximately two thirds of patients presenting with NCCP have GERD or esophageal motility disorders. Esophageal function testing in NCCP should be considered in older patients, men, Caucasians and those presenting with dysphagia.     

Manometric findings of esophageal motor disorders in 240 Brazilian patients with non-cardiac chest pain

Two hundred and forty Brazilian patients with chest pain and normal cardiac evaluation were submitted to computerized esophageal manometry. Endoscopic examination and/or swallow barium studies had excluded obstructive lesions. Motor disorders were found in 63% of patients; non-specific motors disorders and hypotensive lower esophageal sphincter were the most common. The finding of nutcracker esophagus in only 6% of the patients is a quite different rate from what has been previously described in the literature. Esophagitis was observed at endoscopy in 13.4% of the patients, hiatus hernia in 19.7% and peptic gastric or duodenal ulcer in 4.9%. It should be emphasized that after excluding pain as being of cardiac origin an abnormal manometry result points to the esophagus as the probable site of origin of the pain; esophageal investigation is important for establishing proper treatment for these patients.     

Twenty-four-hour ambulatory versus stationary esophageal manometry in the evaluation of esophageal motility in patients with gastroesophageal reflux disease

BACKGROUND: Although stationary manometry commonly reveals esophageal body motility disorders in patients with gastroesophageal reflux disease (GERD), esophageal function cannot be fully and precisely assessed during normal daily activities by this investigatory modality. AIM: To compare the results of 24-hour ambulatory manometry with those of stationary manometry and to determine the specificity and accuracy of the former to detect motility disorders in patients with GERD. PATIENTS AND METHODS: 15 patients with documented GERD were included in the study. Clinical assessment, upper alimentary endoscopy and stationary manometry as well as 24-hour ambulatory manometry with concomitant 24-hour monitoring of the esophageal pH were performed in each patient. RESULTS: 24-hour ambulatory manometry revealed a significant number of dropped or interrupted esophageal contractions in patients who were found to have only complete peristalsis on stationary manometry. Furthermore, in certain patients, ambulatory manometry detected an increased incidence of dropped or interrupted contractions as compared to those recorded during stationary manometry. Ineffective contractions, suggestive of poor esophageal motility, although absent on stationary manometry, were detected in a large number of patients during a 24-hour period of recording. Also, the amplitude of esophageal contractions was clearly overestimated when evaluated by stationary manometry. CONCLUSIONS: 24-hour ambulatory esophageal manometry reveals esophageal motor abnormalities to a greater extent than those demonstrated at stationary manometry, in patients with GERD. This might be of significance in designing the treatment and predicting possible outcome.     

Oesophageal manometry during eating in the investigation of patients with chest pain or dysphagia.

Dysphagia is a frequent cause of referral for oesophageal manometry although the motor response to eating is not routinely studied. We examined symptoms and oesophageal motor patterns in response to eating bread in 30 patients with either gastro-oesophageal reflux (n = 20), or normal oesophageal function tests (n = 10). No patient experienced symptoms while swallowing water but one complained of heartburn and one developed symptomatic oesophageal 'spasm' during eating. In eight further patients, pain or dysphagia which occurred with swallowing bread was associated with aperistalsis. Comparing asymptomatic and symptomatic periods, there was a slight increase in mean swallow frequency from 7.5 (0.79) (SEM) to 9.0 (1.17) swallows per minute (NS; n = 10). The mean number of aperistalsis swallows increased from 4.5 (0.96) per minute to 6.2 (1.30) (p less than 0.01; n = 10). Aperistalsis during symptoms was mainly caused by non-conducted swallows rather than synchronous contractions (mean 5.8 (1.45) per minute compared with 1.2 (0.44]. Aperistalsis can be produced by rapid swallowing in the normal oesophagus through 'deglutitive inhibition'. These results suggest that some patients experience dysphagia associated with aperistalsis perhaps as a response to increased frequency of swallowing. Functional abnormalities of this nature will not be detected by conventional oesophageal manometry.     

Manometric findings in patients with isolated distal gastroesophageal reflux

AIM: To analyze manometric abnormalities in patients with isolated distal reflux and compare these findings in patients with erosive and non-erosive disease.METHODS: Five hundred and fifty patients who presented to the outpatient clinic of Turkiye Yuksek Ihtisas Hospital with gastroesophageal reflux disease-like symptoms were enrolled.Each individual was evaluated with esophageal manometry, 24-h ambulatory pH monitoring, and upper gastrointestinal endoscopy.Manometric findings for the patients with isolated distal reflux were compared to findings in controls who were free of reflux disorders or hypersensitive esophagus.Findings for isolated distal reflux patients with and without erosive reflux disease were also compared.RESULTS: Of the 550 subjects enrolled, 97 (17.6%, mean age 48 years) had isolated distal reflux and 100 had no abnormalities on ambulatory pH monitoring (control group, mean age 45 years).There were no significant differences between the isolated distal re- flux group and control group with respect to age, body mass index, and esophageal body contraction amplitude (EBCA).Mean lower esophageal sphincter pressure was significantly higher in the control group (12.7 ± 10.3 mmHg vs 9.6 ±7.4 mmHg, P = 0.01).Fifty-five (56.7%) of the 97 patients with isolated distal reflux had erosive reflux disease.There were no statistical differences between the erosive reflux disease and non-erosive reflux disease subgroups with respect to mean EBCA, lower esophageal sphincter pressure, or DeMeester score.However, 13% of patients with gastroesophageal re- flux disease had distal wave amplitudes ≤ 30 mmHg, whereas none of the patients with non-erosive reflux disease had distal wave amplitudes in this low category.CONCLUSION: Patients with erosive and non-erosive disease present with similar manometric abnormalities.The only striking difference is the observation of very low EBCA exclusively in patients with erosive disease.     

Role of clinical presentation in diagnosing reflux-related non-cardiac chest pain

INTRODUCTION: Non-cardiac chest pain (NCCP) presents as a frequent diagnostic challenge, with patients tending to use a disproportionate level of health-care resources. Gastroesophageal reflux disease (GERD) is the most frequent cause of NCCP. Thus the typical symptoms of reflux, such as heartburn and regurgitation, when present as predominant symptoms are quite specific for diagnosing GERD but in patients with NCCP the clinical diagnosis of reflux is difficult, and invasive methods or the omeprazole test are required for its detection. The aim of the present study was to evaluate the role of clinical presentation when diagnosing GERD among patients with NCCP. METHODS: Patients with NCCP underwent upper endoscopy, Bernstein and omeprazole tests. The patients were divided into two groups based on GER- or non-GER-related chest pain, and clinical presentation was compared between these two groups. Gastroesophageal reflux disease was considered positive when at least two methods were positive. RESULTS: From 78 NCCP patients (41 male; mean age 50.4 +/- 2.3 years), the chest pain was related to GERD in 35 patients (44.8%). The two groups were the same based on sex and age. The chest pain severity, site, radiation and relation to food, exercise, and sleep were equal in the two groups, except for two symptoms: pain that was relieved by antacid (P < 0.031) and presence of classical reflux symptoms (P < 0.009), seen in the GERD patients. With regard to recent patient history, heartburn and regurgitation symptoms were seen more frequently in GERD patients (P < 0.036 and P < 0.002, respectively). DISCUSSION: Clinical presentation is important in diagnosing GERD in NCCP. Although the chest pain is the same in reflux- and non-reflux-related NCCP, the symptoms of heartburn or regurgitation in the present or recent patient history are diagnostic for GERD-related chest pain.     

High amplitude, peristaltic esophageal contractions associated with chest pain and/or dysphagia.

Esophageal manometric tracings obtained using low-compliance pneumohydraulic infusion systems were reviewed from patients with symptoms of chest pain and/or dysphagia. Using this sytem, we report on 7 symptomatic patients with markedly increased esophageal peristaltic amplitude. Maximal peristaltic amplitude for these 7 patients (225-430 mmHg) was greater than for normals (75-175 mmHg). Mean peristaltic amplitude for the 7 was 170 mmHg, which was greater than for normals (81 +/- 30 mmHg, mean +/- 2 SD). This finding is believed to reflect the sensitivity of currently available manometric systems. It may be possible with these techniques to define more clearly the bulk of presumed esophageal dysfunction, which is at present poorly characterized. The relationship of clinical symptoms to abnormal esophageal motility is often less than optimal and may result from an inability to define "normal" or from inadequacies of currently available techniques. Our observations of a subset of symptomatic patients having peristaltic contractions with amplitudes exceeding the normal range seem to characterize one form of esophageal motility defect. This abnormality was seen more frequently than diffuse esophageal spasm in our laboratory.     

Esophageal motility,heartburn, and gastroesophageal reflux: Variations in clinical presentation of esophageal dysphagia

Dysphagia is a potentially important symptom, often leading to the finding of an anatomical or motility disorder of the esophagus. Dysphagia and heartburn represent two of the most common symptoms associated with esophageal motility disorders. To explore the relationship of symptomatic esophageal dysphagia and heartburn and their association with primary esophageal motor disorders, we have performed a retrospective assessment of 1035 patient evaluations performed at our gastrointestinal laboratory. A clear statistical association of symptomatic dysphagia and heartburn was established; however, no pattern diagnostic of a specific motility disorder was discernible. A sizable fraction of our patient population with dysphagia demonstrated normal esophageal motility. A significant portion of dyspeptic patients exhibited both normal motility and acid exposure. The differences observed between the incidence of subjective symptoms and objective dysfunction may be explained in part by an altered or increased esophageal sensitivity of these patients.     

Comparison of intravenous edrophonium and oesophageal acid perfusion during oesophageal manometry in patients with non-cardiac chest pain.

Sixty consecutive patients referred for evaluation of non-cardiac chest pain had oesophageal manometry. Motility was assessed basally, after edrophonium 80 micrograms/kg iv and during oesophageal perfusion with 0.1 N HCl at 6 and 14 ml/min for eight and seven minutes respectively. A positive response, defined as symptom reproduction with or without abnormal motility, was present in 21 patients (35%) after acid perfusion and 12 (20%) after edrophonium. Eleven of the 12 patients responding to edrophonium also responded to acid perfusion, including most of the patients with primary motility disorders. Significantly greater increases in peristaltic duration, but not amplitude, were recorded after edrophonium (p less than 0.01) and acid perfusion (p less than 0.05) in positive responders, compared with non-responders. Results indicate that acid perfusion during oesophageal manometry may be a more useful stress test than edrophonium and that the mechanism of symptom production may be similar.     

Long-term outcome of patients with non-cardiac chest pain.

OBJECTIVE: To assess long-term outcome for patients with chest pain in our environment, to estimate direct resource use, and to evaluate the influence of patient views regarding pain origin on outcome. PATIENTS AND METHODS: All patients referred to our Department between 1994 and 1998 to undergo pH-metry as a result of chest pain were identified. Those detected were subjected to a structured direct interview on the telephone. RESULTS: 104 patients with a follow-up period (since pH-metry) of 3.76 years were evaluated. Thirty nine percent of patients were free from pain (37.5%), and one had died from a seemingly unrelated cause (1%), whereas the rest still suffered from pain. The mean number of visits per patient during the last year was 2.83 to their general practitioner, 1.04 to an specialist, and 0.99 to an Emergency Unit; hospitalisations were 0.26, and ICU admissions 0.09. Patients who trusted medical diagnoses showed better outcomes than those who did not trust or understand them, in association with lower resource use, particularly Emergency Unit use. CONCLUSION: Patients with chest pain had a favourable life prognosis, but 60% still suffer from pain after nearly 4 years of follow-up, which entails a relevant use of health-care resources. Trust in medical diagnosis seemingly influences outcome, and the use of diagnostic procedures to determine pain origin is thus likely beneficial for patient.     

Management of non-cardiac chest pain: from research to clinical practice

BACKGROUND: Non-cardiac chest pain assessed by cardiologists in their outpatient clinics or by coronary angiography usually has a poor symptomatic functional and psychological outcome. Randomised trials have shown the effectiveness of specialist psychological treatment with those who have persistent symptoms, but such treatment is not always acceptable to patients and may not be feasible in routine clinical settings. OBJECTIVES: To describe a sample of patients referred to cardiac outpatient clinics from primary care in a single health district who were consecutively reassured by cardiologists that there was not a cardiac cause for their presenting symptom of chest pain. DESIGN: Systematic recording of referral and medical information of patients consecutively reassured by cardiologists. Reassessment in research clinic six weeks later (with a view to inclusion in a randomised trial of psychological treatment, which has been separately reported) and followed up at six months. SETTING: A cardiac clinic in a teaching hospital providing a district service to patients referred from primary care. PATIENTS: 133 patients from the Oxfordshire district presenting with chest pain and consecutively reassured that there was no cardiac cause during the recruitment period; 69 had normal coronary angiograms and 64 were reassured without angiography. INTERVENTION: A subgroup (n = 56) with persistent disabling chest pain at six weeks were invited to take part in a randomised controlled trial of cognitive behavioural treatment. MAIN OUTCOME MEASURES: Standardised interview and self report measures of chest pain, other physical symptoms, mood and anxiety, everyday activities, and beliefs about the cause of symptoms at six week assessment; repeat of self report measures at six months. RESULTS: Patients had a good outcome at six weeks, but most had persistent, clinically significant symptoms and distress. Some found the six week assessment and discussion useful. The psychological treatment was helpful to most of those recruited to the treatment trial, but a minority (15%) of those treated appeared to need more intensive and individual collaborative management. Patients reassured following angiography were compared with those reassured without invasive investigation. They had longer histories of chest pain, more often reported breathlessness on exertion, and were more likely to have previously been diagnosed as having angina, treated with antianginal medication, and admitted to hospital as emergencies. CONCLUSION: These findings suggest a need for "stepped" aftercare, with management tailored according to clinical need. This may range from simple reassurance and explanation in the cardiac clinic to more intensive individual psychological treatment of associated underlying and often enduring psychological problems. Simple ways in which the cardiologist might improve care to patients with non-cardiac chest pain are suggested, and the need for access to specialist psychological treatment discussed.     

The contribution of gastroesophageal reflux to chest pain in patients with coronary artery disease.

OBJECTIVE: To describe the effectiveness of investigating and treating the cause of refractory chest pain in patients with coronary artery disease who are receiving optimal antianginal therapy. DESIGN: Cohort study. SETTING: Tertiary referral center. PATIENTS: Between January 1988 and December 1989, 34 patients were identified as having angiographically proven coronary artery disease and atypical chest pain symptoms despite their having received aggressive medical or surgical antianginal therapy, or both. INTERVENTION: Patients with confirmed acid-related symptoms were treated with high-dose histamine-2 (H2) blockers or omeprazole for 8 weeks in an open-label study. MEASUREMENTS: Esophageal manometry and simultaneous 24-hour pH and Holter studies; global improvement in or disappearance of chest pain. RESULTS: Of the 34 patients, 30 (88%) experienced their identical chest pain symptoms during the study. A total of 164 pain episodes was recorded: 38 (23.2%) correlated with acid reflux; 6 (3.7%) were related to cardiac ischemia; and the remaining 120 (73.2%) had no identifiable cause. Of these 30 patients, 20 (67%) had some of their episodes of chest pain (range, 14% to 100%) secondary to acid reflux. After 8 weeks of vigorous acid suppression, 13 of these 20 patients had marked improvement or resolution of chest pain. Four other patients had ischemia-related episodes of chest pain that responded to more aggressive antianginal therapy. No episodes of acid reflux were clearly followed by ischemic chest pain. One patient had both acid- and ischemic-related episodes of chest pain that were indistinguishable. Overall, 24 of 34 (71%) patients had a definite cause of chest pain identified by combined pH and Holter monitoring. CONCLUSIONS: Gastroesophageal reflux disease is a common, treatable cause of chest pain in patients with coronary artery disease who have atypical symptoms and remain symptomatic despite aggressive antianginal therapy. Combined Holter and 24-hour esophageal pH studies are complementary investigations for elucidating the cause of chest pain in these patients.     

Manometric findings during spontaneous chest pain in patients with presumed esophageal "spasms"

Nine patients with intermittent chest pain thought clinically to be secondary to esophageal "spasms" developed typical pain while being studied with an intraluminal transducer probe placed in the distal esophagus. Manometric changes from control periods were examined preceding and during pain episodes. No significant difference in distal esophageal wave duration or amplitude or in frequency of abnormal peristalsis was observed preceding or during pain episodes when compared with nonpain periods over a mean monitoring time of 227 min. No change from the nonpain periods in esophageal baseline pressure occurred during pain episodes, nor was there any other obvious manometric change by gross inspection of the tracings. We conclude that patients clinically suspected of having esophageal "spasms" as the source of chest pain frequently do not, regardless of the presence or absence of motility abnormalities on conventional esophageal manometric studies.     

Ambulatory esophageal manometry,pH-metry,and holter ECG monitoring in patients with atypical chest pain

Standard Holter electrocardiographic (ECG) monitoring was combined with ambulatory esophageal manometry and pH-metry in 25 patients with atypical chest pain in order to determine whether an association could be found between spontaneous pain episodes and ischemic ECG changes or esophageal dysfunction. Results of ambulatory testing were compared to those obtained with standard esophaeal manometry and provocative testing. Twenty-two of the 25 patients experienced a total of 88 pain episodes during ambulatory testing. Although 15 of the 22 patients (68%) experiencing pain during testing had at least one pain episode that corelated temporally with gastroesophageal reflux, esophageal dysmotility or ischemic ECG changes, 65% of all pain episodes were unrelated to abnormal esophageal events or ECG changes. Seventeen percent of pain episodes were associated with gastroesophageal reflux, 15% with esophageal dysmotility,and 2% with a combined acid reflux and esophageal dysmotility event. Only one pain episode was associated with ischemic ECG changes. Twelve of the 15 patients with chest pain episodes associated with reflux or esophageal dysmotility had othe identical pain episodes in which there was no correlation. Reproduction of a patient's pain during standard manometry with provocative testing did not predict a strong correlation between the patient's spontaneous pain episodes and esophageal dysfunction during ambulatory recordings. In summary, patients with atypical chest pain have relatively few spontaneous pain episodes that correlate with gastroesophageal reflux, esophageal dysmotility, or ischemic ECG changes. It appears that different stimuli can trigger identical episodes of chest pain, which suggests that many of these patients may have dysfunction of their visceral pain sensory mechanisms.     

Comparison of esophageal manometry,provocative testing,and ambulatory monitoring in patients with unexplained chest pain

Prolonged ambulatory esophageal pH and pressure monitors are being developed to evaluate noncardiac chest pain. This new technology needs comparison with conventional esophageal tests before determining which studies are most useful in diagnosing and treating esophageal chest pain. Therefore, we studied 45 patients with esophageal manometry, acid perfusion and edrophonium tests, and 24 hr pH and pressure monitoring. Manometry was abnormal in 20 patients (44%) with nutcracker esophagus, the most common motility disorder. Fifteen (33%) had positive acid perfusion test and 24 (55%) positive edrophonium test. During ambulatory monitoring, all patients experienced chest pain with a total of 202 individual events: 32 events (15%) secondary to acid reflux, 15 (7%) secondary to motility abnormalities, 7 (3%) to both pH and pressure changes, and 149 events (74%) occurred in the absence of any abnormal pH or motility changes. Patients with normal manometry were significantly (P less than 0.01) more likely to have acid reflux chest pain events than did nutcracker patients, who had an equal frequency of pH and motility events. A positive acid perfusion test was significantly associated with abnormal pressure events (P = 0.02; odds ratio 5.95), while a positive edrophonium test more likely predicted acid reflux chest pain during 24-hr monitoring (P = 0.007; odds ratio 7.25). Therefore, abnormal manometry and positive provocative tests point to the esophagus as the likely source of chest pain. However, ambulatory pH and pressure monitoring are required to accurately define the relationship between chest pain and acid reflux or motility disorders.(ABSTRACT TRUNCATED AT 250 WORDS)     

Study on the contraction pattern of esophageal body in 27 patients with non-cardiac chest pain

<正>Objective To analyze the differences in the contraction pattern of esophageal body in patients with different types of non-cardiac chest pain( NCCP).Methods From January 1,2019 to December 31,2020,46 NCCP patients visiting the First Affiliated Hospital of Zhejiang Chinese Medical University were selected.According to the Lyon consensus and Rome Ⅳ dignostic criteria,     

食管混合性酸反流和低动力在非心源性胸痛发作的作用研究

目的胃食管反流病（GERD）是引起非心源性胸痛（NCCP）的最常见因素,本研究探讨酸反流和食管动力障碍在NCCP患者中的作用。 方法按照纳入、排除标准选取2018年9月至2019年6月在新疆维吾尔自治区人民医院急救中心以及微创,疝和腹壁外科住院收治的40例NCCP患者和50例典型GERD症状患者,两组患者均行食管24 h pH监测以及高分辨率食管测压监测。 结果NCCP组食管远端收缩平均积分（DCI）明显低于GERD组,并具有统计学意义（P＜0.05）,提示食管运动功能受损。在NCCP组患者中,与胸痛有关的混合性酸反流明显高于GERD组（P＜0.05）。在NCCP组患者中,与NCCP相关的反流发作在食管5、9和15cm处的反流清除时间比GERD组患者期长（28.3±4.21)s vs(22.6±3.28)s;(13.7±1.32)s vs (18.3±1.47)s;(9.58±1.02)s vs(14.3±1.06)s（P＜0.05）。 结论酸反流性质,食管运动功能受损和延缓反流清除时间与NCCP患者症状发作可能存在密切的关系。     

Central sensitization in patients with non-cardiac chest pain: A clinical experimental study

Objective. Patients with non-cardiac chest pain (NNCP) suffer from unexplained and often intractable pain which can pose a major clinical problem. The aim of this study was to investigate nociceptive processing in NNCP patients and their response to experimentally acid-induced oesophageal hyperalgesia using a multimodal stimulation protocol. Material and methods. Ten highly selected patients with NCCP (mean age 43?years, 1?M) were compared with an age- and gender-matched group of 20 healthy subjects. After preconditioning, the distal oesophagus was painfully distended with a balloon using “impedance planimetry”. This method assesses the luminal cross-sectional area of the oesophagus based on the electrical impedance of the fluid inside the balloon. The baseline distensions were done before and after pharmacological relaxation of the smooth muscle with 20?mg butylscopolamine. After baseline distensions, a series of up to 10 mechanical stimuli was performed (temporal summation). The stimulations were repeated after sensitization of the oesophagus induced by acid perfusion. The sensory intensities were assessed during the stimulations and the referred pain area was mapped. Results. At baseline distensions, no differences were seen between patients and controls before and after relaxation of the smooth muscles. The patients tolerated fewer repeated distensions than controls (4.8±0.5 versus 9.1±0.9; p=0.04) and had an increased size of the referred pain areas to the mechanical stimulations (32.9±6.2 versus 64.9±18.3?cm²; p=0.01). After sensitization with acid, the patients developed hyperalgesia (p<0.001), whereas no significant changes were seen in controls. Conclusions. NCCP patients showed facilitated central pain mechanisms (temporal summation and visceral hyperalgesia after sensitization). This could be used in the diagnosis and understanding of the symptoms in these patients.     

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.