Twenty-four-hour esophageal pH monitoring: the most useful test for evaluating noncardiac chest pain

Diagnosis and Management of Functional Chest Pain in the Rome IV Era

Functional chest pain accounts for about a third of the patients with noncardiac chest pain. It is a very common functional esophageal disorder that remains even today a management challenge to the practicing physician. Based on the definition offered by the Rome IV criteria, diagnosis of functional chest pain requires a negative workup of noncardiac chest pain patients that includes, proton pump inhibitor test or empirical proton pump inhibitor trial, endoscopy with esophageal mucosal biopsies, reflux testing, and esophageal manometry. The mainstay of treatment are neuromodulators that are primarily composed of anti-depressants. Alternative medicine and psychological interventions may be provided alone or in combination with other therapeutic modalities.

The Mexican consensus on non-cardiac chest pain

INTRODUCTION

Non-cardiac chest pain is defined as a clinical syndrome characterized by retrosternal pain similar to that of angina pectoris, but of non-cardiac origin and produced by esophageal, musculoskeletal, pulmonary, or psychiatric diseases.

AIM

To present a consensus review based on evidence regarding the definition, epidemiology, pathophysiology, and diagnosis of non-cardiac chest pain, as well as the therapeutic options for those patients.

METHODS

Three general coordinators carried out a literature review of all articles published in English and Spanish on the theme and formulated 38 initial statements, dividing them into 3 main categories: (i)definitions, epidemiology, and pathophysiology; (ii)diagnosis, and (iii)treatment. The statements underwent 3rounds of voting, utilizing the Delphi system. The final statements were those that reached >75% agreement, and they were rated utilizing the GRADE system.

RESULTS AND CONCLUSIONS

The final consensus included 29 statements. All patients presenting with chest pain should initially be evaluated by a cardiologist. The most common cause of non-cardiac chest pain is gastroesophageal reflux disease. If there are no alarm symptoms, the initial approach should be a therapeutic trial with a proton pump inhibitor for 2-4weeks. If dysphagia or alarm symptoms are present, endoscopy is recommended. High-resolution manometry is the best method for ruling out spastic motor disorders and achalasia and pH monitoring aids in demonstrating abnormal esophageal acid exposure. Treatment should be directed at the pathophysiologic mechanism. It can include proton pump inhibitors, neuromodulators and/or smooth muscle relaxants, psychologic intervention and/or cognitive therapy, and occasionally surgery or endoscopic therapy.

Treatment of esophageal (noncardiac) chest pain: an expert review

BACKGROUND & AIMS

Chest pain is a common and frightening symptom. Once cardiac disease has been excluded, an esophageal source is most likely. Pathophysiologically, gastroesophageal reflux disease, esophageal dysmotility, esophageal hypersensitivity, and anxiety disorders have been implicated. However, treatment remains a challenge. Here we examined the efficacy and safety of various commonly used modalities for treatment of esophageal (noncardiac) chest pain (ECP) and provided evidence-based recommendations.

METHODS

We reviewed the English language literature for drug trials evaluating treatment of ECP in PubMed, Cochrane, and MEDLINE databases from 1968-2012. Standard forms were used to abstract data regarding study design, duration, outcome measures and adverse events, and study quality.

RESULTS

Thirty-five studies comprising various treatments were included and grouped under 5 broad categories. Patient inclusion criteria were extremely variable, and studies were generally small with methodological concerns. There was good evidence to support the use of omeprazole and fair evidence for lansoprazole, rabeprazole, theophylline, sertraline, trazodone, venlafaxine, imipramine, and cognitive behavioral therapy. There was poor evidence for nifedipine, diltiazem, paroxetine, biofeedback therapy, ranitidine, nitrates, botulinum toxin, esophageal myotomy, and hypnotherapy.

CONCLUSIONS

Ideally, treatment of ECP should be aimed at correcting the underlying mechanism(s) and relieving symptoms. Proton pump inhibitors, antidepressants, theophylline, and cognitive behavioral therapy appear to be useful for the treatment of ECP. However, there is urgent and unmet need for effective treatments and for rigorous, randomized controlled trials.

Acid peptic diseases: pharmacological approach to treatment

Acid peptic disorders are the result of distinctive, but overlapping pathogenic mechanisms leading to either excessive acid secretion or diminished mucosal defense. They are common entities present in daily clinical practice that, owing to their chronicity, represent a significant cost to healthcare. Key elements in the success of controlling these entities have been the development of potent and safe drugs based on physiological targets. The histamine-2 receptor antagonists revolutionized the treatment of acid peptic disorders owing to their safety and efficacy profile. The proton-pump inhibitors (PPIs) represent a further therapeutic advance due to more potent inhibition of acid secretion. Ample data from clinical trials and observational experience have confirmed the utility of these agents in the treatment of acid peptic diseases, with differential efficacy and safety characteristics between and within drug classes. Paradigms in their speed and duration of action have underscored the need for new chemical entities that, from a single dose, would provide reliable duration of acid control, particularly at night. Moreover, PPIs reduce, but do not eliminate, the risk of ulcers in patients taking NSAIDs, reflecting untargeted physiopathologic pathways and a breach in the ability to sustain an intragastric pH of more than 4. This review provides an assessment of the current understanding of the physiology of acid production, a discussion of medications targeting gastric acid production and a review of efficacy in specific acid peptic diseases, as well as current challenges and future directions in the treatment of acid-mediated diseases.

Proton pump inhibitor treatment of patients with gastroesophageal reflux-related chronic cough: A comparison between two different daily doses of lansoprazole

AIM: To compare two different daily doses of lansoprazole given for 12 weeks and to assess the role of gastrointestinal (GI) investigations as criteria for selecting patients.

METHODS: Out of 45 patients referred for unexplained chronic persistent cough, 36 had at least one of the GI investigations (endoscopy, 24-h esophageal pH-metry and a 4-week trial of proton pump inhibitor (PPI) therapy) positive and were randomly assigned to receive either 30 mg lansoprazole o.d. or 30 mg lansoprazole b.i.d. for 12 weeks. Symptoms were evaluated at baseline (visit 1) after the PPI test (visit 2) and after the 12-week lansoprazole treatment period (visit 3).

RESULTS: Thirty-five patients completed the study protocol. Twenty-one patients (60.0%) reported complete relief from their cough with no difference between the two treatment groups (58.8% and 61.1% had no cough in 30 mg lansoprazole and 60 mg lansoprazole groups, respectively). More than 80% of the patients who had complete relief from their cough at the end of the treatment showed a positive response to the PPI test.

CONCLUSION: Twelve weeks of lansoprazole treatment even at a standard daily dose, is effective in patients with chronic persistent cough. A positive response to an initial PPI test seems to be the best criterion for selecting patients who respond to therapy.

Chest pain from gastroesophageal reflux disease in patients with coronary artery disease

Management of patients with coronary artery disease is a major challenge for physicians, patients, and the healthcare system. Chest pain experienced by patients with coronary disease can be of noncardiac origin, and symptoms frequently related to gastroesophageal etiologies. The distal esophagus and the heart share a common afferent nerve supply, suggesting that location and radiation of perceived pain may be identical. In addition, there is substantial overlap between the prevalence of coronary disease and gastroesophageal reflux disease. Many physicians, including cardiologists, prescribe acid-reducing therapy to coronary patients. However, no prospective, randomized studies to date have evaluated the potential benefit of such treatments to prevent chest pain symptoms for these patients. We review the studies on noncardiac chest pain demonstrating reflux in patients with and without coronary disease. Also, the association of reflux with exertional chest pain and cardiac syndrome X is discussed. A rationale is presented for prevention of noncardiac chest pain in coronary patients, and the potential role of acid-suppressive therapy in managing these patients is discussed.

[Role of esophageal provocative tests in the investigation of patients with chest pain of undetermined origin]

BACKGROUND

Traditional methods employed in esophageal investigation of patients with chest pain of undetermined origin includes upper endoscopy, esophageal manometry and pH monitoring. These methods many times disclose abnormalities that can only be enrolled as the possible cause of chest pain. Provocative tests can reproduce pain in the laboratory, establishing its esophageal origin.

OBJECTIVES

Determine the positivity of acid perfusion test, edrophonium and balloon distension in patients with chest pain of undetermined origin and compare with results of traditional exams, establishing the gain for the diagnosis of esophageal pain.

RESULTS

Forty patients with chest pain of undetermined origin (normal coronary angiography), 80% female, mean age of 54.7 years were submitted to traditional exams and provocative tests. Upper endoscopy disclosed erosive esophagitis in two (5%) and peptic ulcer in one (2.5%), esophageal manometry was abnormal in 60%. pH monitoring was abnormal in 14 (35%) with a positive symptom index in 7. Chest pain was considered of proved esophageal origin by traditional exams in 7 (17.5%) patients with a positive symptom index and of probable esophageal origin in 19 (47.5%) being 8 with gastroesophageal reflux disease and 11 abnormal esophageal motility. In 14 (35%) an esophageal origin could not be demonstrated. The acid perfusion test was positive in 10 (25%), edrophonium test in 8 (20%) and balloon distension test in 15 (37.5%) and at least one provocative test was positive in 23 (57.5%) patients. The introduction of provocative tests allowed the diagnosis of proved esophageal pain in 12 of 19 (63.1%) patients with probable esophageal pain and in 6 of 14 (42.8%) with normal or inconclusive traditional exams what represented a diagnostic gain of 45% (18/40). Two patients had negative provocative tests and a positive symptom index, making a total of 25 (62.5%) patients with proved esophageal pain.

Functional chest pain: nociception and visceral hyperalgesia

Functional chest pain is a common, yet poorly understood entity. The focus of this review is to explore the evolving research and clinical approaches with a particular emphasis on the sensory or afferent neuronal dysfunction of the esophagus as a key player in the manifestation of this pain syndrome. Although once regarded as a psychologic or esophageal motility disorder, recent advances have shown that many of these patients have visceral hyperalgesia. Whether visceral hypersensitivity is a central or peripheral perturbation of the gut-brain axis remains debatable. Response to empirical therapy with high-dose proton pump inhibitors, upper endoscopy, or prolonged recording of esophageal pH may identify gastroesophageal reflux disease as a source of chest pain. Esophageal balloon distension study can serve as a useful test for identifying hypersensitivity. Newer techniques, including functional magnetic resonance imaging, magnetoencephalogram, and cortical evoked potentials, are being investigated. High doses of proton pump inhibitors and low doses of tricyclic antidepressants or trazadone remain the mainstay of therapy, although several new approaches including theophylline have been shown to be beneficial.

Attitudes and referral patterns of primary care physicians when evaluating subjects with noncardiac chest pain--a national survey

Noncardiac chest pain (NCCP) may affect up to 23% of the U.S. population. The clinical approach and referral patterns of primary care physicians (PCPs) when evaluating NCCP subjects are unknown. We aimed to determine the preferences of diagnostic tests, referral patterns, and treatment plans of NCCP patients by PCPs. PCPs were randomly selected from the American Medical Association national membership list. A 24-item questionnaire was mailed, which focused on demographic information, characteristics of practice, preferences of diagnostic tests, referral patterns, and treatment plans. Two hundred five (40%) PCPs returned the questionnaire (mean age, 49; 77% males; practice type--community-based, 40.5%; hospital-based, 10.7%; and combined, 47.3%; physician type--internists, 46.3%; family physicians, 44.4%; general practitioners, 4.9%; and others, 2.9%). The mean number of NCCP patients seen in the past 6 months was 108 (6.4% of total patients) and 79.5% were treated primarily by PCPs. The three most common diagnostic tests used were empirical proton pump inhibitor (PPI) trial (45.6%), chest radiograph (39.9%), and upper endoscopy (18.7%). Most PCPs reported that they are either comfortable (44.6%) or very comfortable (21.2%) in diagnosing NCCP. The three most commonly used therapeutic modalities for NCCP were PPIs (37.8%), lifestyle modification (33.7%), and H2 blockers (12.4%). Of those NCCP patients referred to a subspecialist, most ended up in gastroenterology (75.6%), followed by cardiology (7.8%) and pulmonary (1.6%) clinics. We conclude that most PCP's diagnose and treat NCCP patients without referring them to a gastroenterologist. However, diagnostic and treatment strategies may not follow the current understanding and knowledge of the disorder.

Sensory testing of the esophagus

Originally, sensory testing of the esophagus included the acid perfusion test and the edrophonium test, which were developed to assess patients with non-cardiac chest pain. In the last 2 decades interest in functional esophageal disorders has increased and thus further understanding of the underlying mechanisms of esophageal pain required development of new sensory testing techniques. Balloon distension using a computerized electronic device, electrical stimulation and impedance planimetry have generated important information about esophageal sensory thresholds for pain in different disease states. Intraluminal ultrasonography has been used to determine the physiologic changes of the muscle wall of the esophagus during perception of typical esophageal symptoms. Central evaluation of patients undergoing esophageal stimulation has recently been introduced to assess cerebral activation in different esophageal disorders. However, many studies using esophageal sensory testing are afflicted with significant design flaws, making interpretation of the results very difficult. This is primarily due to lack of recognition of factors that can modulate esophageal sensation.

The effect of an empirical trial of high-dose lansoprazole on symptom response of patients with non-cardiac chest pain--a randomized, double-blind, placebo-controlled, crossover trial

BACKGROUND

Empirical trial with high-dose omeprazole has been shown to be a sensitive tool for diagnosing patients with gastro-oesophageal reflux disease-related non-cardiac chest pain.

AIM

To determine the clinical value of an empirical trial of high-dose lansoprazole in detecting patients with gastro-oesophageal reflux disease-related non-cardiac chest pain.

METHODS

Patients who were referred by a cardiologist after a comprehensive evaluation, with at least three episodes per week of unexplained chest pain as the predominant symptom, were enrolled into the study. Oesophageal mucosal disease was determined by upper endoscopy followed by 24-h oesophageal pH monitoring to assess acid exposure. Patients were then randomized to either placebo or lansoprazole 60 mg am and 30 mg pm for 7 days. After a washout period of 1 week, patients crossed over to the other arm of the study for an additional 7 days. Patients completed a daily diary assessing severity and frequency of chest pain as the predominant symptom throughout the baseline treatment and washout periods. The lansoprazole empirical trial was considered diagnostic if chest pain score improved > or =50% than baseline.

RESULTS

Of the 40 patients with non-cardiac chest pain that were enrolled, 18 (45%) had erosive oesophagitis and/or abnormal pH test (gastro-oesophageal reflux disease-positive) and 22 (55%) had both tests negative (gastro-oesophageal reflux disease-negative). Of the gastro-oesophageal reflux disease-positive patients, 14 (78%) had significantly higher symptom improvement on lansoprazole than on placebo (22%) (P = 0.0143). Of the gastro-oesophageal reflux disease-negative group, two (9.1%) markedly improved on the medication and eight (36.3%) on placebo (P = 0.75). The sensitivity and specificity of the lansoprazole empirical trial was 78 and 80%, respectively. By day 2, 12 (85.7%) of the gastro-oesophageal reflux disease-related non-cardiac chest pain responders had either complete or almost complete symptom resolution.

CONCLUSIONS

The lansoprazole empirical trial is highly sensitive and specific for diagnosing gastro-oesophageal reflux disease-related non-cardiac chest pain patients. The trial enables diagnosing most of the responders within the first 2 days and thus a shorter duration of therapy may be considered in a subset of non-cardiac chest pain patients.

Gastroesophageal reflux disease (GERD) and chest pain. Results of laparoscopic antireflux surgery

BACKGROUND

Laparoscopic fundoplication cures heartburn and regurgitation in patients with gastroesophageal reflux disease (GERD) but its effect on the chest pain that is also experienced by some patients is less clear. Confusion stems from the fact that it is difficult to determine preoperatively whether the chest pain is actually caused by the reflux. Therefore, we designed a study in patients with GERD and chest pain that would assess the value of pH monitoring in establishing a correlation between the symptom and the disease, the predictive value of pH monitoring on the results of surgical treatment, and the outcome of laparoscopic fundoplication on chest pain in patients with GERD.

METHODS

Of 487 patients who underwent laparoscopic fundoplication for GERD at our institution between October 1992 and July 2000, 165 (34%) complained of chest pain in addition to heartburn and regurgitation. Their symptoms had been present for an average of 118 months. The pH monitoring tracings were analyzed for a correlation between episodes of reflux and chest pain. The mean length of follow-up was 13 months.

RESULTS

Among the 165 patients with chest pain, the relationship between pain and reflux during pH monitoring was as follows: 39 patients (group A) experienced no chest pain during the study; in 28 patients (group B), chest pain correlated with reflux in <40% of instances; in 98 patients (group C), chest pain correlated with reflux in ?40% of instances. Chest pain improved postoperatively in 65% of group A patients, 79% of group B patients, and 96% of group C patients (group C vs A and B: p <0.05). Heartburn and regurgitation resolved or improved in 97% and 95% of patients, respectively.

CONCLUSIONS

These data show that pH monitoring helped to identify a relationship between chest pain and reflux; and when the two coincided, the chest pain was relieved by antireflux surgery.

Upper gastrointestinal evaluation of Chinese patients with non-cardiac chest pain

AIMS

To test the usefulness of upper gastrointestinal investigations and quality of life assessment in Chinese patients with non-cardiac chest pain.

METHODS

Seventy-eight consecutive patients with non-cardiac chest pain underwent upper endoscopy. Eight patients had upper gastrointestinal pathology (10%). The remaining 70 patients received acid perfusion test, oesophageal manometry and 24-h ambulatory oesophageal pH (n=65)/manometry (n=61), and the results were compared with those of healthy controls (n=20). Symptoms and quality of life (SF-36) were assessed by standard validated questionnaire.

RESULTS

Significant acid reflux symptoms were present in five (5/70, 7%) patients. Abnormal 24-h oesophageal pH, indicating gastro-oesophageal reflux, was found in 19 (19/65, 29%) patients. The percentage of simultaneous contractions was higher and the percentage peristalsis was lower in patients with non-cardiac chest pain when compared with normal subjects by 24-h ambulatory manometry. Patients with non-cardiac chest pain had a lower SF-36 score when compared to controls.

CONCLUSIONS

Typical acid reflux symptoms are uncommon in Chinese patients with non-cardiac chest pain, but abnormal 24-h pH results, indicating gastro-oesophageal reflux, were found in 29% of patients. Ineffective contractions were more frequently found in patients with non-cardiac chest pain by 24-h ambulatory manometry, which may have a bearing on the impaired quality of life in such patients. Upper gastrointestinal investigations are useful for the evaluation of Chinese patients with non-cardiac chest pain.

Gastroesophageal reflux: the features in elderly patients

AIM: To compare the features of gastroesophageal reflux disease between elderly and younger patients.

METHODS: Twenty-four hour pH-monitoring and endoscopy were per formed for the 66 elderly patients with typical gastroesophageal reflux symptoms, and the results were compared with 112 symptomatic younger patients.

RESULTS: The results of 24-h pH-monitoring and endoscopy showe d that the elderly patients had pathological reflux and reflux esophagitis more frequently than the younger patients. Percentage time with pH < 4 in elderly patients with reflux esophagitis was 32.5% in 24 h, as compared with 12.9% in the younger patients with reflux esophagitis (P < 0.05). The elderly patients with reflux esophagitis have longer periods of acid reflux in both upright and supine positions than the younger patients. Endoscopy showed that 20.8% of elderly patients had grade III/IV esophagitis, whereas only 3.4% of younger patients had grade III/IV esophagitis (P < 0.002). Percentages of grades I/II esophagitis in the two groups were 12.5% and 26.5%, respectively (P < 0.002).

CONCLUSION: Elderly patients, as compared with younger patients, have more severe gastroesophageal reflux and esophageal lesions. The incompetence of lower esophageal sphincter and the presence of hiatal hernia may be important factors leading to the difference in incidence and severity of reflux esophagitis between elderly and younger patients.

The cost-effectiveness of the omeprazole test in patients with noncardiac chest pain

PURPOSE

Recent evidence suggests that an empiric trial of omeprazole (the "omeprazole test") is sensitive and specific for diagnosing gastroesophageal reflux disease (GERD) as the cause of noncardiac chest pain. Our objective was to examine the clinical, economic, and policy implications of alternative diagnostic strategies for patients with noncardiac chest pain.

METHODS

Decision analysis was used to evaluate the clinical and economic outcomes of two diagnostic strategies that begin with the omeprazole test (60 mg daily for 7 days) followed sequentially by invasive testing utilizing endoscopy, ambulatory 24-hour esophageal pH monitoring, and esophageal manometry as necessary, compared with two traditional strategies involving sequential invasive diagnostic tests. Cost estimates were based on Medicare reimbursement and the Red Book of average wholesale drug prices. Probability estimates were derived from a systematic review of the medical literature.

RESULTS

The average cost per patient for the four diagnostic strategies varied from $1,859 to $2,313. Strategies utilizing the initial omeprazole test resulted in 84% of patients being symptom free at 1 year, compared with 73% to 74% for the strategies that began with invasive tests. The strategy of the omeprazole test, followed if necessary by ambulatory pH monitoring, then manometry, and then endoscopy, was both most effective and least expensive. It led to an 11% improvement in diagnostic accuracy and a 43% reduction in the use of invasive diagnostic tests, thus yielding an average cost savings of $454 per patient, compared with the strategy of beginning with endoscopy, then pH monitoring, and then manometry.

CONCLUSIONS

Among patients with noncardiac chest pain, diagnostic strategies that begin with the omeprazole test result in reduced costs, improved diagnostic certainty, and a greater proportion of symptom-free patients at 1 year than do traditional strategies that begin with invasive diagnostic tests.

Five-year audit of ambulatory 24-hour esophageal pH-manometry in clinical practice

BACKGROUND

Esophageal function testing was developed to aid diagnosis in patients with negative endoscopy. Although combined 24-h esophageal pH-manometry is now commercially available, its routine clinical effectiveness has not yet been studied.

METHODS

From 1992 to 1996 we evaluated 303 consecutive patients who were first-time referrals to our unit for 24-h esophageal pH-manometry. The referral indications were gastroesophageal reflux disease, 47.2%; dysphagia, 18.5%; non-cardiac chest pain, 14.9%; connective tissue disease, 13.2%; and symptomatic patients after antireflux surgery, 6.3%.

RESULTS

Overall, esophageal function testing altered the diagnosis of 44% of the patients, confirmed it in 38%, and specifically changed the management of 66%. The final clinical 'diagnosis' was reflux disease, 54% (32% with non-specific esophageal motility disorder); connective tissue disease, 9.9%; achalasia, 9.6%; other specific esophageal motility disorders, 3.3%; non-specific esophageal motility disorders, 6.9%; and normal, 16.2%. The cost per testing was estimated to be US$305 and per change in management US$465.

CONCLUSION

Combined 24-h pH-manometry has been shown to be a useful and cost-effective test for the management of selected patients in whom the primary investigation was insufficient.

The impact of gastroesophageal reflux disease on health-related quality of life

BACKGROUND

Gastroesophageal reflux disease (GERD) affects health-related quality of life.

METHODS

We enrolled 533 adults with a history of heartburn symptoms for at least 6 months of moderate to severe heartburn in 4 of the 7 days before study entry. Patients were treated with ranitidine 150 mg twice a day for 6 weeks and Gelusil antacid tablets as needed. We measured physician-rated symptoms and the Medical Outcomes Study short-form 36 (SF-36) Health Survey at baseline and after 6 weeks of treatment. Baseline results were compared with normative data for the US population and for patients with selected chronic diseases. Treatment response was defined as no episode of moderate to severe heartburn for 7 days. Statistical significance was set at P <0.001.

RESULTS

GERD patients reported significantly worse scores on all 8 SF-36 scales, physical function and well-being, and emotional well-being compared with the general population. Patients with GERD reported worse emotional well-being than patients with diabetes or hypertension. Treatment responders demonstrated significantly less pain and better physical function, social function, vitality, and emotional well-being compared with nonresponders.

CONCLUSIONS

Patients with GERD experience decrements in health-related quality of life compared with the general population. The impact of GERD is most striking on measures of pain, mental health, and social function. Successful treatment for GERD results in improvements in health-related quality of life.

Evaluation of chest pain in the emergency department

The evaluation of chest pain in the emergency setting should be systematic, risk based, and goal driven. An effective program must be able to evaluate all patients with equal thoroughness under the assumption that any patient with chest pain could potentially be having an MI. The initial evaluation is based on the history, a focused physical examination, and the ECG. This information is sufficient to categorize patients into groups at high, moderate, and low risk. Table 14 is a template for a comprehensive chest-pain evaluation program. Patients at high risk need rapid initiation of appropriate therapy: thrombolytics or primary angioplasty for the patients with MIs or aspirin/heparin for the patients with unstable angina. Patients at moderate risk need to have an acute coronary syndrome ruled in or out expediently and additional comorbidities addressed before discharge. Patients at low risk also need to be evaluated, and once the likelihood of an unstable acute coronary syndrome is eliminated, they can be discharged with further evaluation performed as outpatients. Subsequent evaluation should attempt to assign a definitive diagnosis while also addressing issues specific to risk reduction, such as cholesterol lowering and smoking cessation. It is well documented that 4% to 5% of patients with MIs are inadvertently missed during the initial evaluation. This number is surprisingly consistent among many studies using various protocols and suggests that an initial evaluation limited to the history, physical examination, and ECG will fail to identify the small number of these patients who otherwise appear at low risk. The solution is to improve the sensitivity of the evaluation process to identify these patients. It appears that more than simple observation is required, and at the present time, no simple laboratory test can meet this need. However, success has been reported with a number of strategies including emergency imaging with either radionuclides such as sestamibi or echocardiography. Early provocative testing, either stress or pharmaceutic, may also be effective. The added value of these tests is only in their use as part of a systematic protocol for the evaluation of all patients with acute chest pain. The initial evaluation of the patient with chest pain should always consider cardiac ischemia as the cause, even in those with more atypical symptoms in whom a cardiac origin is considered less likely. The explicit goals for the evaluation of acute chest pain should be to reduce the time to treat MIs and to reduce the inadvertent discharge of patients with occult acute coronary syndromes. All physicians should become familiar with appropriate risk stratification of patients with acute chest pain. Systematic strategies must be in place to assure rapid and consistent identification of all patients and the expedient initiation of treatment for those patients with acute coronary syndromes. These strategies should include additional methods of identifying acute coronary syndromes in patients initially appearing as at moderate or low risk to assure that no unstable patients are discharged. All patients should be followed up closely until the cardiovascular evaluation is completed and, when possible, a definitive diagnosis is determined. Finally, this must be done efficiently, cost-effectively, and in a manner that will result in an overall improvement in patient care.

The diagnosis and management of gastroesophageal reflux disease

GERD is a common clinical problem. Generally, its clinical presentation and management are straightforward. Greater awareness of the numerous extraesophageal manifestations of the disease aids patients and physicians in appropriate recognition and treatment. Medical therapy is effective in the majority of cases but often requires long-term medication for acceptable symptom control. A small, but significant proportion of patients presents with or develops complications of GERD, most importantly Barrett's esophagus. Although the logistics of long-term surveillance of persons with Barrett's esophagus is unclear, the association of this metaplastic change with esophageal adenocarcinoma underscores the importance of regular follow-up.

Frequency and site of gastroesophageal reflux in patients with chest symptoms. Studies using proximal and distal pH monitoring

Prolonged ambulatory pH monitoring was performed on 89 patients with previous diagnosis of asthma (27 patients), chronic cough (28 patients), noncardiac chest pain (34 patients), and on 27 healthy control subjects. The extent of gastroesophageal reflux (GER) was determined using a catheter containing two antimony pH electrodes positioned 5 cm and 20 cm above the superior border of the manometrically determined lower esophageal sphincter. Reflux was defined as a drop in pH to < 4 in the distal esophagus. We compared both pH < 4 and pH < 5 as the beginning of reflux episodes for the proximal esophagus. Considering the confidence interval of 95% in healthy control subjects as a normality criterion, we found a prevalence of abnormal distal GER in 44% of asthmatics, 50% of patients with cough, and 53.8% of patients with noncardiac chest pain. Abnormal proximal acid exposure was found in 24% of asthmatics, 10.7% of patients with cough and 44.1% of patients with chest pain. Distal acid exposure was significantly longer than proximal esophageal acid exposure in all patient groups (p < 0.05). There were no differences in the evaluation of proximal GER comparing pH < 4 with pH < 5. The data also indicate a tendency toward upright, rather than supine acid exposure. These results support the use of 24-h pH monitoring in patients with chest complaints and indicate that GER may frequently be involved in the pathogenesis. They do not support the theory that proximal GER is a specific etiologic factor in chronic cough or asthma.

The symptom-association probability: an improved method for symptom analysis of 24-hour esophageal pH data

BACKGROUND/AIMS

All methods currently used to quantify the temporal relationships between symptoms and episodes of gastroesophageal reflux, as assessed by 24-hour pH monitoring, have major shortcomings. The aim of this study was to develop and validate a simple, all-comprising statistical method to calculate the probability that gastroesophageal reflux episodes and symptoms are associated.

METHODS

The 24-hour pH signal was divided into consecutive 2-minute periods. These periods and the 2-minute periods preceding the onset of symptoms were evaluated for the occurrence of reflux. Fisher's Exact Test was then applied to calculate the probability (P value) that reflux and symptom episodes were unrelated. Finally, the symptom-association probability (SAP) was calculated as (1.0 - P) x 100%. The SAP values found in 184 24-hour esophageal pH tests were compared with the symptom index and the symptom sensitivity index.

RESULTS

Discordance between the SAP and the symptom index was found in 21 patients (11%) and discordance between the SAP and the symptom-sensitivity index in 28 (15%). False-positive and false-negative symptom index values occurred preferentially in patients with small and large numbers of symptom episodes during the test, respectively (P < 0.05).

CONCLUSIONS

The SAP is a single, simple, quantitative measure of the strength of the association between symptoms and reflux episodes that is devoid of the disadvantages inherent to previously used methods.

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.

Chronic cough due to gastroesophageal reflux. Clinical, diagnostic, and pathogenetic aspects

BACKGROUND

Gastroesophageal reflux (GER) is a common cause of chronic cough. Moreover, chronic cough can be the sole presenting manifestation of GER disease (GERD). It has been suggested recently that GER most often causes chronic cough by stimulating the distal esophagus. To gain further diagnostic and pathophysiologic knowledge, we prospectively evaluated a group of patients with chronic cough likely to be due to GER with extensive gastrointestinal and respiratory studies and then observed their response to antireflux therapy.

METHODS

We prospectively characterized 12 subjects whose chronic cough was likely to be due to GER by chest radiographs, barium esophagography, 24-h esophageal pH monitoring (EPM) with probes in the distal and proximal esophagus, esophagoscopy, and bronchoscopy. Then, prior to instituting antireflux therapy, we objectively counted coughs during the distal esophageal infusion of 0.1 N HCl or 0.9 percent saline solution administered in a randomized, double-blind, standardized fashion (ie, Bernstein acid-perfusion test).

RESULTS

Gastroesophageal reflux was determined to cause cough in all subjects based on disappearance of cough with antireflux therapy. It was clinically "silent" in 75 percent. The EPM was the test most frequently abnormal (sensitivity, 92 percent). Distal esophageal data revealed that 10 of 12 subjects had GER-induced coughs (12 +/- 12) while only 7 of 12 had an abnormal esophageal pH conventional parameter (eg, percent time pH < 4). Compared with the distal esophagus, GER to the proximal esophagus occurred (p = 0.017) and induced cough (p = 0.004) less often. Compared with baseline (9.3 +/- 17.6), there were no differences in coughs induced by the infusion of saline solution (9.2 +/- 15.9) or acid (15.1 +/- 26.7); the number of coughs induced by acid was negatively correlated with distal esophageal acid-GER events during EPM (r = -0.64, p = 0.01). Neither bronchoscopy nor chest radiographs were consistent with aspiration.

CONCLUSIONS

There is a clinical profile that prospectively predicts which patients have chronic cough due to GER. The cough was most likely due to stimulation of the distal esophagus, not aspiration. Intraesophageal acid is unlikely to be the sole mediator in gastric juice causing the cough. While EPM is the single most helpful diagnostic test, conventionally utilized diagnostic indices of GERD can be misleadingly normal; observing GER-induced coughs is more frequently helpful.

Gastroesophageal reflux: diagnosis and management

The pathologic potential of chronic esophagitis cannot be overemphasized. Persistent reflux causing cycles of mucosal damage followed by healing may eventually lead to end-stage disease, with development of peptic stricture. The most effective drugs available are those that inhibit acid production. Drugs that will enhance lower esophageal function are still in the future.

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.