Analysis of 24-hour esophageal pressure and pH data in unselected patients with noncardiac chest pain

Esophageal motility and reflux testing. State-of-the-art and clinical role in the twenty-first century

Esophageal function testing has an important place in the investigation of a significant proportion of patients with esophageal disorders. Appropriate application of these tests requires a proper understanding of their capabilities and limitations and careful primary assessment by other modalities. Esophageal manometry is most useful for assessing significant troublesome dysphagia in the absence of organic obstruction. Esophageal pH monitoring is an important adjunct to clinical assessment and endoscopy in the diagnosis of reflux disease. Although it is the gold standard for the measurement of esophageal acid exposure and assessment of the relationship of symptoms to reflux, there are weakness in both of these functions that should be understood when applying the test to the diagnosis of reflux disease.

Oesophageal sensation assessed by electrical stimuli and brain evoked potentials--a new model for visceral nociception

Sensory thresholds and brain evoked potentials were determined in 12 healthy volunteers using electrical stimulation of the oesophagus 28 and 38 cm from the nares. The peaks of the evoked potentials were designated N for negative deflections and P for positive. Continuous electrical stimulation (40 Hz) at the 38 cm position resembled heartburn (five of 12 subjects) while non-specific ('electrical') sensations were provoked at 28 cm (10 of 12). Thresholds of sensation and of pain were lower at the initial than the second determination, but did not differ with respect to stimulation site. The pain summation threshold to repeated stimuli (2 Hz, 5 stimuli) was determined for the first time in a viscus. This threshold was lower than the pain threshold to single stimuli at 38 cm (p < 0.02). Evoked potential latencies did not change significantly over a six month period while the N1/P2 amplitude was higher at the first measurement (p < 0.05). P1 and N1 latencies were significantly shorter 38 cm (medians 100 and 141 ms) than 28 cm from the nares (102 and 148 ms) (p = 0.04 and p = 0.008). Electrical stimulation of the oesophagus may serve as a human experimental model for visceral pain. Longer evoked potential latencies from the proximal compared with distal stimulations provide new information about the sensory pathways of the oesophagus.

Esophageal motility disorders and their coexistence with pathologic acid reflux in patients with noncardiac chest pain

BACKGROUND

The aim of this study was to determine which motility data of patients with noncardiac chest pain (NCCP) differ from those of controls on the basis of long-term manometry and to evaluate the coexistence of motility disorders and pathologic acid reflux. Further, motility disorders were tested as to whether they were secondary to acid reflux.

METHODS

Combined long-term pH/manometry was performed in 95 patients with NCCP, using one pH-electrode and two pressure transducers. The motility data were compared with those of healthy controls (n = 40). In addition, an intraindividual patient-oriented motility analysis was performed. Evaluated were the amplitude, the duration in the distal and proximal esophagus, and the type of propagation, propulsive and simultaneous, of esophageal contractions. Ten patients with pathologic acid reflux and hypermotility disorders received 20 mg omeprazole twice daily and were investigated again 4 weeks after therapy began.

RESULTS

The median distal pressure amplitude (39.4 versus 28.9 mmHg, p < 0.0001) and the median percentage of simultaneous contractions (18.5% versus 10%; p < 0.0001) were significantly higher in patients with NCCP than in controls. In addition, patients whose symptoms correlated with abnormal motility (n = 18) had a significantly higher median duration of contractions (3.8 sec versus 3.2 sec; p < 0.03) than controls Patients with pathologic acid reflux showed a higher median distal pressure amplitude (38.3 mmHg versus 28.9 mmHg; p < 0.0001) and median percentage of simultaneous contractions (18% versus 10%; p < 0.0001) than controls. Furthermore, a high rate of coexistence with hypermotility disorders was observed (64%). These disorders persisted after acid suppression therapy.

CONCLUSIONS

Patients with NCCP differ from controls in their esophageal motility. Simultaneous contractions of increased amplitude and duration are pathologic. The intraindividual patient-oriented motility analysis is an appropriate evaluation method. Hypermotility disorders occur often in patients with pathologic acid reflux, but apparently they are not dependent on it.

Automatic detection of esophageal pressure events. Is there an alternative to rule-based criteria?

Ambulatory long-term motility recording is used increasingly for evaluation of esophageal function. The enormous amount of motility data recorded by this method demands subsequent computer analysis. One of the most crucial steps of this analysis becomes the process of automatic selection of relevant pressure peaks at the various recording levels. Until now, this selection has been performed entirely by rule-based systems, requiring each pressure deflection to fit within predefined rigid numerical limits in order to be detected. However, due to great variations in the shapes of the pressure curves generated by muscular contractions, rule-based criteria do not always select the pressure events most relevant for further analysis. We have therefore been searching for a new concept for automatic event recognition. The present study describes a new system, based on the method of neurocomputing. A large sample of normal esophageal pressure deflections was used as a "learning set," and the performance of the trained neural networks was subsequently verified on different sets of data from normal subjects. Our trained networks detected pressure deflections with sensitivities of 0.79-0.99 and accuracies of 0.89-0.98, depending on the recording level within the esophageal lumen. The neural networks often recognized peaks that clearly represented true contractions but that had been rejected by a rule-based system. We conclude that neural networks have potentials for automatic detections of esophageal, and possibly also other kinds of gastrointestinal, pressure variations.

Chronic cough and hoarseness in patients with severe gastroesophageal reflux disease. Diagnosis and response to therapy

Gastroesophageal reflux may be responsible for atypical symptoms such as chronic cough and hoarseness. Our aim was to evaluate and treat patients with severe gastroesophageal reflux and chronic cough or hoarseness with intensive antireflux therapy. Twenty-seven patients with typical heartburn symptoms in addition to significant cough or hoarseness were treated with aggressive antireflux therapy. We recorded the response of each symptom to the antireflux therapy. Two patients were lost to follow-up. Twenty of the 25 (80%) patients showed some improvement in cough or hoarseness, nine (36%) had no atypical symptoms at follow-up. The response of heartburn to therapy was strongly predictive of successful therapy for the atypical symptoms. Cough and hoarseness improved in only two of the five patients with residual heartburn symptoms compared to 18 of 20 patients with no heartburn (P < 0.04). Only patients with no heartburn symptoms at follow-up had complete resolution of atypical symptoms. There were no important differences on ambulatory pH monitoring between partial and complete responders. Improvement in atypical reflux symptoms, such as chronic cough and hoarseness, is common with aggressive antireflux therapy. There are no findings on ambulatory esophageal pH monitoring that uniquely identify patients who are likely to respond to antireflux therapy.

Long-term esophageal manometry in healthy subjects. Evaluation of normal values and influence of age

Although long-term esophageal manometry is increasingly used in clinical practice, the normal values of contraction parameters are poorly defined. In addition, limited data are available on the effect of age on esophageal motility. Therefore, 44 healthy subjects (age range: 22-85 years) were investigated with a probe combining two pressure transducers 10 cm apart. All subjects were asked to follow their normal daily routine. The characteristics of contraction events (amplitude, duration) and type of propagation (propulsive, simultaneous) were analyzed for the total time and predefined periods: meal, daytime (interprandial), and supine. Equally high distal and proximal median pressure amplitudes (39.5 and 37 hPa) and durations (3.4 and 3.2 sec) were observed. The median percentages of propulsive and simultaneous waves were 56% and 10%. The individual contraction characteristics differed significantly in these three selected periods for most motility parameters: distal and proximal pressure amplitudes, distal duration, and propulsive contractions. To evaluate the influence of age on normal values, the subjects were divided into two age groups (median age: 28.5 and 62.4 years). In the elderly group the distal pressure amplitude, the distal duration, and the percentage of simultaneous waves increased, whereas the percentage of propulsive waves, the proximal pressure amplitude, and the proximal duration decreased. However, the differences observed were only minor and rarely reached the level of statistical significance (distal pressure amplitude and duration in the supine period). In conclusion, the physiological motor activity of the esophagus is characterized by significant diurnal variation. Furthermore the motility data are little influenced by age.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastroesophageal reflux in patients with angiographically normal coronary arteries: an uncommon cause of exertional chest pain

OBJECTIVES

To investigate the association between exertional chest pain and gastroesophageal reflux in patients with normal coronary angiograms and in controls by measuring oesophageal pH during treadmill exercise tests and to compare the results with routine ambulatory monitoring.

DESIGN

Case control study.

SETTING

Tertiary referral cardiac unit.

PATIENTS

50 consecutive patients with chest pain and completely normal coronary angiograms and 16 controls with coronary artery stenoses.

MAIN OUTCOME MEASURES

Episodes of acid reflux and chest pain during treadmill exercise; a symptom index expressing the percentage of episodes of pain related to acid reflux during ambulatory monitoring.

RESULTS

Four (8%) patients and two (12%) controls had reflux during treadmill exercise (NS). 32 (64%) and 16 (100%) reported chest pain, but only three (6%) and two (12%) had coincident reflux (NS). Reflux was as frequent before, during, and after treadmill exercise (five (8%) v six (9%) v two (3%)) in the 66 subjects; (NS). 19 (38%) patients and three (19%) controls had abnormal reflux on ambulatory monitoring (NS). Eight (16%) and three (19%) had a symptom index > 50%, but six and two of these reported pain without coincident reflux during treadmill exercise.

CONCLUSION

There are many potential causes of chest pain in patients with angiographically normal coronary arteries. Although gastroesophageal reflux is commonly implicated and many patients have a high incidence of spontaneous reflux during ambulatory monitoring, it rarely occurs during exertion and the association with chest pain is poor.

Temporal relationships between episodes of non-cardiac chest pain and abnormal oesophageal function

Analysis of the association between symptoms and abnormal oesophageal function is a central part of 24 hour oesophageal pressure and pH recording in patients with non-cardiac chest pain. Such studies have used different time windows including a period after the onset of pain. Since stress and pain can induce oesophageal motor abnormalities and transient lower oesophageal sphincter relaxations, a proportion of the motor abnormalities and the reflux episodes observed after the onset of pain may be a consequence rather than the cause of that pain. This study aimed to assess this possibility in patients with chest pain that was presumed to be of oesophageal origin by comparing the results of analysis using time windows before and after the onset of pain. Forty eight patients experienced a total of 166 spontaneous chest pain episodes during 24 hour ambulatory monitoring. A time window beginning two minutes before and ending at the onset of pain (-2/0) was compared with a window beginning at the onset of pain and ending two minutes afterwards (0/+2). The percentage of episodes related to reflux, abnormal oesophageal motility, or neither were 22.9%, 24.7%, and 52.4% in the -2/0 time window and 9.0%, 22.3%, and 68.7% in the 0/+2 time window, respectively. However, 11 of the 37 episodes associated with abnormal motility in the 0/+2 time window were preceded by a reflux episode, and 19 of these 37 episodes had abnormal motility in the -2/0 time window. Consequently, in only seven of the 166 chest pain episodes (4.2%) in two patients were the findings consistent with secondary oesophageal motor disorders provoked by pain. Likewise, only six of the 166 chest pain episodes (3.6%) were consistent with reflux provoked by pain. These findings indicate that in patients with non-cardiac chest pain, gastro-oesophageal reflux and oesophageal motor abnormalities are rarely a consequence of the pain.

Southwestern Internal Medicine Conference: the syndrome of angina pectoris: role of visceral pain perception

Angina pectoris is a pain syndrome caused by coronary arteriosclerosis but also by a number of other disorders, including microvascular angina, gastroesophageal reflux (GER), and esophageal dysmotility. The relationship between abnormal physiology and pain in these conditions is complex. Simultaneous ambulatory monitoring of esophageal pH and motility has demonstrated that patients may have identical episodes of chest pain with acid reflux, dysmotility, both types of events, or neither. Patients may have anginal chest pain with inflation of an esophageal balloon, and patients with microvascular angina may have pain with catheter manipulation in the right atrium. Recent evidence suggests that disorders of visceral pain perception may play a role in both chest pain of esophageal origin and microvascular angina. The physiology of visceral pain is reviewed, including concepts of convergence of somatic and visceral afferent input, descending modulation of pain perception, and sensitization of visceral pain afferents. An approach to evaluation and treatment of chest pain in patients with angiographically normal coronary arteries is outlined.

Esophageal dysfunction as a cause of angina pectoris ("linked angina"): does it exist?

PURPOSE

The differentiation between cardiac and esophageal causes of retrosternal chest pain is notoriously difficult. Theoretically, cardiac and esophageal causes may coexist. It has also been reported that gastroesophageal reflux and esophageal motor abnormalities may elicit myocardial ischemia and chest pain, a phenomenon called linked angina pectoris. The aim of this study was to assess the incidence of esophageal abnormalities as a cause of retrosternal chest pain in patients with previously documented coronary artery disease.

PATIENTS AND METHODS

Thirty consecutive patients were studied, all of whom had undergone coronary arteriography. The patients were studied after they were admitted to the coronary care unit with an attack of typical chest pain. On electrocardiograms (ECGs) taken during pain, 15 patients (group I) had new signs of ischemia; the other 15 patients (group II) did not. In none of the patients were cardiac enzymes elevated. As soon as possible, but within 2 hours after admission, combined 24-hour recording of esophageal pressure and pH was performed. During chest pain, 12-lead ECG recording was carried out.

RESULTS

In group I, all 15 patients experienced one or more pain episodes during admission, 25 of which were associated with ischemic electrocardiographic changes. The other two episodes were reflux-related. Only one of the 25 ischemia-associated pain episodes was also reflux-related, ie, it was preceded by a reflux episode. In group II, 19 chest pain episodes occurred in 11 patients. None of these was associated with electrocardiographic changes, but 8 were associated with reflux (42%) and 8 with abnormal esophageal motility (42%).

CONCLUSION

Linked angina is a rare phenomenon.

What is the optimal time window in symptom analysis of 24-hour esophageal pressure and pH data?

Since noncardiac chest pain is the only well-established indication for 24-hr esophageal pH and pressure recording, the analysis of the association between chest pain episodes and esophageal motility abnormalities or reflux is the most important part of data analysis in 24-hr monitoring. Until now, different time windows have arbitrarily been used by various research groups. The aim of this study was to determine the optimal time window for symptom analysis in 24-hr esophageal pH and pressure monitoring. For this purpose repetitive symptom association analysis was carried out, using time windows of various onsets and durations. For each time window, the symptom indices for reflux and dysmotility were calculated. The symptom index for both reflux and dysmotility showed a gradual increase for windows with increasingly early onset, following a pattern that would be predicted on the basis of Poisson's theory. However, both indices had a relatively sharp cutoff point at 2 min before the onset of pain. Both indices only showed a predictable gradual increase when the time window starting at -2 min was extended beyond the moment of pain onset. It is concluded that the optimal time window for symptom analysis in 24-hr esophageal pH and pressure recording begins at 2 min before the onset of pain and ends at the onset of pain.

Acid clearance and oesophageal sensitivity in patients with progressive systemic sclerosis

This study examined the hypothesis that impaired oesophageal peristalsis was associated with delayed oesophageal clearance of acid in patients with progressive systemic sclerosis (PSS), some of whom are thought to have impaired oesophageal sensitivity to acid. Sixteen patients with PSS had: (a) oesophageal manometry and endoscopy; (b) acid perfusion of the oesophagus with simultaneous measurement of intraoesophageal pH during perfusion and for the next 10 minutes; (c) 22 hour monitoring of intraoesophageal pH; and (d) an evaluation of reflux symptoms during and after perfusion and during overnight pH monitoring. By oesophageal manometry, eight patients had normal peristalsis and eight patients had impaired peristalsis. Oesophageal endoscopy was unremarkable in patients with normal peristalsis, whereas all patients with impaired peristalsis had oesophagitis. The time needed to clear the oesophagus of perfused acid was shorter (p < 0.01) in patients with normal peristalsis and acid clearance time was significantly correlated (p < 0.01) with acid exposure time during overnight pH monitoring. During and after oesophageal perfusion, the nature, duration, and severity of symptoms did not differ between the groups, but overnight symptoms lasted longer (p < 0.05) in patients with impaired peristalsis. It is concluded that in PSS: (1) Impaired oesophageal motility delayed the clearance of acid and increased the exposure time to acid. (2) Acid clearance time is a useful parameter of impaired oesophageal motor function. The assessment of acid clearance time can be used as an alternative to overnight pH monitoring, to assess the impairment of oesophageal acid clearance. (3) Oesophageal sensitivity to acid was preserved in patients with impaired peristalsis and oesophagitis. (4) Reflux symptoms lasted longer in patients with prolonged oesophageal acid exposure but were still reported for a small fraction of the total acid exposure time. Thus, reflux symptoms reflect poorly prolonged exposure of the oesophagus to acid and are not a reliable guide to acid injury of the oesophagus in PSS.

Role of upper esophageal reflex and belch reflex dysfunctions in noncardiac chest pain

Fifty-four patients examined for noncardiac chest pain (NCCP), showing no esophageal motor disorder or gastroesophageal reflux disease compatible with NCCP, were subjected to an intraesophageal balloon distension test and a study of the belching reflex provoked by intraesophageal air injection. Thirty-three control subjects were also studied, allowing us to define high-threshold belchers (group I) as those who belched during two of three 40-ml distensions and low-threshold belchers (group II) as those who did not. The balloon distension test induced NCCP in 64% of the patients in group I, and in 14% of the patients in group II (P < 0.01). High-threshold belching was a factor favoring the positivity of the balloon distension test. This result supports the hypothesis that esophageal distension by air due to a belching disorder may be the mechanism responsible for NCCP in some patients with an abnormal sensitivity to balloon distension.

Changes in oesophageal pH associated with gastro-oesophageal reflux. Are traditional criteria sensitive for detection of reflux?

Traditionally, gastro-oesophageal reflux is deemed to have occurred when oesophageal pH falls below 4. Other 'non-traditional' pH changes that do not fall below pH 4, that fall below 4 for only brief intervals, or that occur when basal pH is less than 4 are usually disregarded. The aim of this study was to determine whether these non-traditional pH changes represent gastro-oesophageal reflux or are artefactual. The 3-h postprandial combined oesophageal pH and manometric records of 22 patients referred for investigation of suspected gastro-oesophageal reflux were reviewed. All pH falls of > or = 0.5 pH units were analysed for manometric evidence of reflux that was classified as definite, probable, or possible. In total, 196 traditional and 223 non-traditional pH events were scored and analysed. The majority of traditional (80%) and non-traditional (60%) events were associated with definite manometric evidence of reflux, although a greater proportion of non-traditional events were associated with only probable evidence of reflux (33%) compared with traditional events (18%). The proportions of possible reflux were similar in the two groups. Limiting pH events to only those satisfying traditional criteria excluded an additional 32% with definite manometric evidence of reflux and 49% with definite or probable evidence of reflux. Most pH falls that remained above 4 or fell across 4 for < 15 sec occurred in the 1st h postprandially, compared with traditional pH events, which occurred equally throughout the 3-h period. We conclude that traditional criteria for scoring pH episodes substantially underestimate the number of reflux episodes.

Bursts of non-deglutitive simultaneous contractions may be a normal oesophageal motility pattern

The frequency and characteristics of non-deglutitive motor activity of the human oesophagus and its relation to motility patterns in the antrum and upper small intestine were studied in 25 fasted healthy subjects. Motility of the oesophagus, antrum, and upper small intestine was recorded by means of a manometric perfused catheter system. The most striking non-deglutitive motility pattern consisted of repetitive bursts of non-sequential pressure peaks occurring in the smooth muscle portion of the oesophagus. The mean number of pressure peaks per burst was 2.7 (SD 2) waves with a mean amplitude of 19.5 (SD 9.9) mm Hg and a duration of 3.09 (SD 0.22) seconds. The highest amplitude was 80 mm Hg and the longest burst consisted of 13 repetitive waves. The bursts were recorded up to a distance of 15-20 cm above the lower oesophageal sphincter. Ninety five per cent of the bursts occurred during a 15 minute period before the onset of phase 3 of the migrating motor complex in the antral or upper small intestinal area, or during the lower oesophageal sphincter component of the migrating motor complex. In conclusion, spontaneous bursts of non-sequential pressure peaks occurred in the smooth muscle part of the human oesophagus in relation to phase 3 of the migrating motor complex. They represent the oesophageal body component of phase 3 of the migrating motor complex and are not a sign of oesophageal motor abnormalities.

The symptom index. Differential usefulness in suspected acid-related complaints of heartburn and chest pain

The symptom index is a quantitative measure developed for assessing the relationship between gastroesophageal reflux and symptoms. Controversy exists, however, over its accuracy and the appropriate threshold for defining acid-related symptoms of heartburn and chest pain. Therefore, a retrospective review was done of 153 consecutive patients referred to our esophageal laboratory. Three groups were identified: patients with normal 24-hr pH tests and no esophagitis, patients with abnormal 24-hr pH tests and no esophagitis, and patients with abnormal 24 hr pH values and endoscopic esophagitis. If symptoms occurred during the pH study, a symptom index (number of acid related symptoms/total number of symptoms x 100%) was calculated separately for heartburn and chest pain. Heartburn and chest pain episodes were similar among the three groups. However, the mean symptom index for heartburn was significantly (P < 0.001) higher in the patient groups with abnormal pH values [abnormal pH/no esophagitis: 70 +/- 7.1% (+/- SE); abnormal pH/esophagitis: 85 +/- 4.6%] as compared to those with normal studies, ie, functional heartburn (26 +/- 10.7%). The mean symptom index for chest pain was similar for all three groups. Using receiver operating characteristic curves, a heartburn symptom index > or = 50% had excellent sensitivity (93%) and good specificity (71%) for acid reflux disease, especially if patients complain of multiple episodes of heartburn. In contrast, an optimal symptom index threshold for defining acid-related chest pain episodes could not be defined.

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 esophageal 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 correlated 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 other 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.

Does diet affect values obtained during prolonged ambulatory pressure monitoring

With the development of a portable high-capacity data-recording device and fully automated computer analysis, it is now possible to monitor esophageal motility in an ambulatory outpatient setting and over a complete circadian cycle. However, limited data are available on the characteristics and pattern of esophageal motility in healthy subjects, particularly the effects of meals. We studied the effect of food types (liquid vs solid) and standardized vs nonstandardized diet on 17 healthy volunteers with a probe combining three miniature pressure transducers 5 cm apart. All subjects followed the same diet regimen: a standardized breakfast, strict liquid lunch, and no restriction for composition and quantity of dinner. The characteristics of contraction events (amplitude, duration, velocity, slope, area under curve) and their propagation types (peristaltic, simultaneous, segmental, retrograde) were analyzed and compared to supine and interprandial periods. The contraction characteristics and the propagation pattern were identical for the three types of meals. In comparison with the interprandial and supine periods, the three types of meals showed higher percent peristaltic contractions and smaller percent simultaneous contractions. The individual contraction characteristics were, however, not significantly different. Higher percentages of simultaneous, retrograde, and segmental contractions were found during the supine period than either the perprandial or interprandial periods. This study indicates that characteristics of esophageal contractions and propagation pattern are similar for meals of different composition and quantity. In comparison with interprandial and supine periods, the meals are always characterized predominantly by peristaltic contractions. Thus, standardization of meals during prolonged ambulatory pressure monitoring is not required.

Ambulatory esophageal monitoring in noncardiac chest pain

The esophageal origin of angina-like noncardiac chest pain can be identified with certainty only when spontaneous chest pain episodes are associated with gastroesophageal reflux, abnormal esophageal motility, or both. Since noncardiac chest pain typically occurs infrequently, prolonged monitoring is required to establish such an association. Ambulatory esophageal monitoring offers the additional advantages of studying the patient in everyday life and avoiding hospital admission. Although the amplification and storage of 24-hour signals in a portable recorder no longer poses technical problems, the complexity of the analysis of the recorded signals should not be underestimated. For noncardiac chest pain, the most relevant part of the analysis is the association between chest pain episodes and the recorded esophageal signals. To determine whether contraction amplitude or duration during chest pain episodes is abnormal, their measurements are compared with baseline values from the same patient. Fully automated analysis by computer is feasible and, since it avoids observer bias, preferable. The yield of 24-hour monitoring in noncardiac chest pain reported by different groups of investigators varies considerably. Motor abnormalities have been identified as the cause of chest pain in 4.5-18% of patients studied, and reflux in 4.5-25%. In addition, some patients had both dysmotility- and reflux-related pain episodes. As expected, the yield of the technique is higher in patients with frequent pain episodes. In patients who do not experience pain during 24-hour monitoring, the technique cannot provide a firm diagnosis of pain of esophageal origin. Recently, a much higher yield of 24-hour monitoring was reported in patients with noncardiac chest pain admitted to a coronary-care unit. A total of 76% of these patients were found to have either reflux- or dysmotility-related chest pain. Despite its relatively low yield, the addition of esophageal pressure monitoring to ambulatory pH monitoring is worthwhile and probably also cost-effective in patients with frequent episodes of unexplained chest pain.

Therapy of noncardiac chest pain: is there a role for surgery?

Esophageal distention, motor abnormalities, or exposure of the esophageal mucosa to acidic gastric juice can cause chest pain indistinguishable from that of myocardial ischemia in patients with and without coronary artery disease. In these situations the exact cause of the symptom needs to be established prior to any surgical therapy. An antireflux procedure relieves chest pain in patients with increased esophageal acid exposure more reliably than medical therapy. The best results are obtained in patients in whom a direct correlation of the symptom with reflux episodes can be documented on 24-hour esophageal pH monitoring. Ambulatory 24-hour esophageal motility monitoring shows that esophageal motor disorders are a less frequent cause of noncardiac chest pain than suggested by standard manometry or provocation tests. Furthermore, chest pain episodes in patients with esophageal motor abnormalities are not associated with single contractions of excessively high amplitude or duration. Rather, the symptom appears to be triggered by an increased frequency of simultaneous, multipeaked, and repetitive motor activity. In appropriately selected patients with chest pain and dysphagia secondary to an esophageal motor abnormality, a long esophageal myotomy eliminates the ability of the esophagus to produce these contractions, reduces or eliminates dysphagia, and decreases the frequency and severity of chest pain episodes.

Irritable esophagus

An esophageal origin of noncardiac chest pain is generally accepted if prolonged pH and pressure recordings show that the pain episodes correlate in time with acid reflux, esophageal motor abnormalities, or a combination of both, or if provocative testing (acid perfusion, edrophonium, balloon distention) is positive. Many patients with noncardiac chest pain of esophageal origin are said to have an irritable esophagus. Irritable esophagus has been defined in two ways. Some researchers suggest it is actually a lowered esophageal pain threshold, based on the finding that such patients feel chest pain at lower balloon volumes than controls during intraesophageal balloon distention; they are said to be hypersensitive to balloon distention. Hypersensitivity to an esophageal stimulus is generally found in patients with noncardiac chest pain of esophageal origin, and hypersensitivity to a single stimulus is one criterion for a diagnosis. Our group defines irritable esophagus as a condition in which several different stimuli result in the same type of chest pain. Accordingly, we have grouped patients with esophageal chest pain into three categories: (a) patients with an acid-sensitive esophagus, in whom spontaneous pain episodes can be related to acid reflux (with or without accompanying motor disorders), and/or the acid perfusion test is positive; (b) patients with a mechano-sensitive esophagus, in whom the spontaneous pain episodes can be related to motility disturbances (without reflux), and/or the edrophonium test or balloon distention test is positive; (c) patients with an irritable esophagus, in whom some spontaneous pain episodes are related to reflux, while others are related to abnormal motility (without reflux). The last group includes patients whose spontaneous chest pain is related to reflux, with a positive motility tests; whose pain is related to abnormal motility, with a positive reflux test; and patients with positive tests for both reflux and abnormal motility. Seven studies examined a total of 281 noncardiac chest pain patients using prolonged pH and pressure recordings and provocative tests. An acid-sensitive, a mechano-sensitive, or an irritable esophagus was found in 20%, 14%, and 24% of patients, respectively.

Spectrum of esophageal disorders in children with chest pain

The charts of 83 children with chest pain who underwent esophageal manometry followed by esophagogastroscopy were reviewed. Forty-seven (57%) had normal esophageal histology and normal motility (group I). Esophagitis and normal motility were demonstrated in 15 children (group II), normal esophageal histology and esophageal dysmotility in 13 (group III), and both esophagitis and abnormal motility in 8 (group IV). Diffuse esophageal spasm and achalasia were the most common motility disorders identified (in seven and four patients, respectively). The presence and duration of symptoms, the age, and the gender were not different among the four patient groups. After six months of H2-receptor blockade, 12 of 15 group II patients were asymptomatic, whereas a significantly smaller percentage (five of 18) of patients with abnormal esophageal motility responded to esophageal dilation or treatment with calcium channel blockade, H2-receptor antagonist, and/or prokinetic agents (P less than 0.01). These data suggest that the evaluation of children with chest pain should include esophageal motility testing and esophagoscopy, even in the absence of other gastrointestinal-associated symptoms, and that while treatment of esophagitis results in resolution of symptoms, motility disorders were relatively refractory to therapy.

Acute noncardiac chest pain in a coronary care unit. Evaluation by 24-hour pressure and pH recording of the esophagus

Twenty-four-hour recording of esophageal pressure and pH was performed successfully in 41 patients admitted to the coronary care unit of a general hospital who had an episode of acute, prolonged retrosternal chest pain and who were initially suspected of suffering from coronary artery disease (severe angina pectoris, myocardial infarction), but in whom the pain was subsequently shown not to be of cardiac origin. The recordings were analyzed with fully automated techniques. A pain episode was considered to be related to abnormal esophageal motility when contraction amplitudes or durations in the pain episode exceeded the patient's upper limit of normal (97.5th percentile) or when the proportion of abnormal propagated contractions (simultaneous, nontransmitted) in the pain episode was significantly increased (chi 2 test). Thirty patients (73%) had one or more pain episodes (in total 63 pain episodes) during the 24-hour recording. Forty-three percent of the pain episodes was related to abnormal motility and 30% to reflux, and 27% was not related to esophageal function disturbance. Using the criterium that the symptom index had to be greater than or equal to 75%, it was found that the pain was related to reflux in 13 patients (43%) and to motor abnormalities in 10 patients (33%). It is concluded that in the majority of patients acutely admitted with noncardiac chest pain, esophageal motor abnormalities and reflux can be shown to be the likely cause of the symptoms.

Clinical application of 24-hour ambulatory esophageal pH and pressure monitoring

Recently, 24-h recording of intraesophageal pH and pressure signals in ambulatory subjects has become possible. Several research applications of the technique have emerged, but until now only a few clinical applications have been established, the most important of which is noncardiac chest pain. In the computer analysis of the signals, the patient with noncardiac chest pain is used as his or her own control; motility and pH profiles during pain are compared with asymptomatic base-line values obtained from the same patient. Automated analysis by means of a computer avoids observer bias and saves time. By means of 24-h monitoring, motor abnormalities have been identified as the cause of the chest pain in 4.5% to 18% and reflux in 4.5% to 25% of the patients studied. In addition, patients were identified who have both dysmotility- and reflux-related pain episodes. The yield of 24-h monitoring is highest in patients who have frequent pain episodes. A high yield of 24-h monitoring was found in patients with noncardiac chest pain admitted to a coronary care unit. Seventy-six per cent of these patients were found to have either reflux- of dysmotility-related chest pain. Patients with proven coronary artery disease who do not respond well to adequate treatment frequently have gastroesophageal reflux (39%) or esophageal motor abnormalities (50%) as the cause of their ongoing pain attacks. In these patients, identification of the esophageal cause of the symptoms not only helps the physician to select the optimal treatment but also reduces the patient's need for medical care.

Alkaline reflux oesophagitis

Duodenal and gastric contents do reflux into the oesophagus and acid alone certainly causes oesophageal damage which will be worsened by pepsin. In the patient who has undergone gastrectomy duodenal secretions may also be harmful. There is evidence that when the two mix there may be a toxic synergism, leading to mucosal disruption and intracellular damage to oesophageal cells which produces the clinical picture of reflux oesophagitis, with or without symptoms. Clear evidence of the toxicity of duodenal refluxate in humans is lacking, but the ability to measure bile and acid reflux continuously, together with a method of detecting oesophageal damage at a cellular level should help to solve this long debated problem.

Esophageal motility disorders and chest pain

Motility abnormalities have long been recognized as a possible esophageal cause of chest pain; however, their exact role and prevalence remain largely unknown. Baseline manometry and the various provocative tests may suggest an esophageal origin, but their yield is low. The recent advent of prolonged ambulatory monitoring of intraesophageal pressure and the assessment of psychological factors are contributing to a clearer understanding of this complex problem.

Gastroesophageal reflux disease as a cause of chest pain

Patients with recurrent chest pain free of significant coronary artery disease account for 10% to 30% of patients undergoing coronary angiography. Recent studies suggest that gastroesophageal reflux disease may be very common in these patients. The cause of this chest pain seems to be related primarily to an acid-sensitive mucosa regardless of the presence of esophagitis. Unfortunately, a careful history will not distinguish chest pain arising from a cardiac versus an esophageal source. Therefore, all patients must undergo a thorough cardiac evaluation before assuming that acid reflux is the cause of their complaints. Initial gastroenterology evaluation will usually include upper GI endoscopy or barium studies, possibly with acid perfusion (Bernstein) testing, or both. However, the more sensitive and specific test for acid-related disease is prolonged esophageal pH monitoring. This study quantifies the amount of acid reflux but, more importantly, identifies the relationship between chest pain and acid reflux episodes. Patients should be studied in the outpatient setting with emphasis placed on performing activities that replicate their chest pain. Although we presume that acid-induced chest pain responds as well as heartburn to vigorous antireflux regimens, there are few studies to address this issue. Nevertheless, I have had great success in treating these patients with either high-dose H2 blockers or omeprazole therapy.

Gastroesophageal reflux disease

Gastroesophageal reflux disease, usually manifested by frequent heartburn, occurs in approximately 10% of our adult population. The presence of a hiatal hernia is usually associated with, but does not necessarily cause, LES dysfunction, allowing acid reflux to produce esophageal and aerodigestive symptoms. The mucosa can be extensively damaged and, ultimately, a columnar lining, termed Barrett's esophagus, a premalignant condition, can develop. Treatment with H2-antagonists has been nirvana to some patients, but has proved only partially helpful to others. Adjunctive agents may increase relief and may help heal erosive esophagitis in some patients, but side effects and cost limit their use. Maintenance therapy with full doses is required, as the relapse rate for this chronic condition is high. Omeprazole temporarily heals almost everyone with otherwise resistant GERD, but it is currently used only on a short-term basis unless surgery, eminently successful in well-selected patients, is contraindicated.