Oesophageal ischaemia in motility disorders associated with chest pain

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.

Temporal and spectral properties of esophageal mucosal blood perfusion: a comparison between normal subjects and nutcracker esophagus patients

BACKGROUND

The mechanism of esophageal pain in patients with nutcracker esophagus (NE) and other esophageal motor disorders is not known. Our recent study shows that baseline esophageal mucosal perfusion, measured by laser Doppler perfusion monitoring, is lower in NE patients compared to controls. The goal of our current study was to perform a more detailed analysis of esophageal mucosal blood perfusion (EMBP) waveform of NE patients and controls to determine the optimal EMBP biomarkers that combined with suitable statistical learning models produce robust discrimination between the two groups.

METHODS

Laser Doppler recordings of 10 normal subjects (mean age 43 ± 15 years, 8 males) and 10 patients (mean age 47 ± 5.5 years., 8 males) with NE were analyzed. Time and frequency domain features were extracted from the first twenty-minute recordings of the EMBP waveforms, statistically ranked according to four independent evaluation criterions, and analyzed using two statistical learning models, namely, logistic regression (LR) and support vector machines (SVM).

KEY RESULTS

The top three ranked predictors between the two groups were the 0.5 and 0.75 perfusion quantile values followed by the surface of the EMBP power spectrum in the frequency domain. ROC curve ranking produced a cross-validated AUC (area under the curve) of 0.93 for SVM and 0.90 for LR.

CONCLUSIONS & INFERENCES

We show that as a group NE patients have lower perfusion values compared to controls, however, there is an overlap between the two groups, suggesting that not all NE patients suffer from low mucosal perfusion levels.

Low esophageal mucosal blood flow in patients with nutcracker esophagus

Nutcracker esophagus (NE) is characterized by high-amplitude peristaltic esophageal contractions, and these patients often present with symptoms of "angina-like" or noncardiac chest pain. Tissue ischemia is a known cause of visceral pain, and the goal of our present study was to determine whether esophageal wall blood perfusion (EWBP) is reduced in patients with NE. Fourteen normal subjects (mean age 51 yr, 11 men) and 12 patients (mean age 53 yr, 9 men) with NE and noncardiac chest pain were investigated. The EWBP was measured continuously using a custom-designed laser Doppler probe tethered to a Bravo capsule, which anchored it to the esophageal wall. The baseline EWBP in normal subjects was 651 ± 27 perfusion units. In patients with NE, the baseline EWBP was significantly lower than in the normal subjects (451 ± 32 perfusion units). The EWBP decreased after injection of edrophonium (which increases muscle contractions) and increased following sublingual nitroglycerin administration (which relaxes muscle) in normal subjects, as well as in NE patients. Spontaneous pain events during the recording period were often associated with drops in the EWBP. We propose that low EWBP leads to hypoxia of the esophageal tissue, which may be a mechanism of esophageal pain in patients with NE.

Esophageal wall blood perfusion during contraction and transient lower esophageal sphincter relaxation in humans

We recently reported that esophageal contraction reduces esophageal wall perfusion in an animal study. Our aim was to determine esophageal wall blood perfusion (EWBP) during esophageal contraction and transient lower esophageal sphincter relaxations (TLESRs) in humans. We studied 12 healthy volunteers. A custom-designed laser Doppler probe was anchored to the esophageal wall, 4-6 cm above the LES, by use of the Bravo pH system so that the laser light beam stay directed toward the esophageal mucosa. A high-resolution manometry equipped with impedance electrodes recorded esophageal pressures and reflux events. Synchronized pressure, impedance, pH, and EWBP recordings were obtained during dry and wet swallows and following a meal. Stable recordings of laser Doppler EWBP were only recorded when the laser Doppler probe was firmly anchored to the esophageal wall. Esophageal contractions induced by dry and wet swallows resulted in 46 ± 9% and 60 ± 10% reduction in the EWBP, respectively (compared to baseline). Reduction in EWBP was directly related to the amplitude (curvilinear fit) and duration of esophageal contraction. Atropine reduced the esophageal contraction amplitude and decreased the EWBP reduction associated with esophageal contraction. TLESRs were also associated with reduction in the EWBP, albeit of smaller amplitude (29 ± 3%) but longer duration (19 ± 2 s) compared with swallow-induced esophageal contractions. We report 1) an innovative technique to record EWBP for extended time periods in humans and 2) contraction of circular and longitudinal muscle during peristalsis and selective longitudinal muscle contraction during TLESR causes reduction in the EWBP; 3) using our innovative technique, future studies may determine whether esophageal wall ischemia is the cause of esophageal pain/heartburn.

Functional aspects of distal oesophageal spasm: the role of onset velocity and contraction amplitude on bolus transit

BACKGROUND

Distal oesophageal spasm is a rare and under-investigated motility abnormality. Recent studies indicate effective bolus transit in varying percentages of distal oesophageal spasm patients.

AIM

Explore functional aspects including contraction onset velocity and contraction amplitude cut-off values for simultaneous contractions to predict complete bolus transit.

METHODS

We re-examined data from 107 impedance-manometry recordings with a diagnosis of distal oesophageal spasm. Receiver operating characteristic analysis was conducted, regarding effects of onset velocity on bolus transit taking into account distal oesophageal amplitude and correcting for intra-individual repeated measures.

RESULTS

Mean area under the receiver operating characteristic curve for saline and viscous swallows were 0.84±0.05 and 0.84±0.04, respectively. Velocity criteria of >30 cm/s when distal oesophageal amplitude>100 mmHg and 8 cm/s when distal oesophageal amplitude<100 mmHg for saline and 32cm/s when distal oesophageal amplitude>100 mmHg and >7 cm/s when distal oesophageal amplitude<100 mmHg for viscous had a sensitivity of 75% and specificity of 80% to identify complete bolus transit. Using these criteria, final diagnosis changed in 44.9% of patients. Abnormal bolus transit was observed in 50.9% of newly diagnosed distal oesophageal spasm patients versus 7.5% of patients classified as normal. Distal oesophageal spasm patients with distal oesophageal amplitude>100 mmHg suffered twice as often from chest pain than those with distal oesophageal amplitude<100 mmHg.

CONCLUSION

The proposed velocity cut-offs for diagnosing distal oesophageal spasm improve the ability to identify patients with spasm and abnormal bolus transit.

Noncardiac chest pain: diagnostic evaluation

Noncardiac chest pain (NCCP) is a common and challenging clinical problem. It is estimated that more than 70 million Americans (23% of the population) suffer from this condition yearly. Patients with NCCP represent a diagnostic dilemma. Their chest pain is often indistinguishable from cardiac pain leading to extensive and expensive evaluations. Once coronary artery disease and other cardiac and pulmonary sources of chest pain are excluded, patients are frequently referred to gastroenterologists to look primarily for esophageal sources of pain. A variety of diagnostic tests are available to the practicing clinician to identify the origin of pain, including ambulatory pH testing, esophageal motility, upper endoscopy, provocative testing and even therapeutic trials.

Effect of esophageal contraction on esophageal wall blood perfusion

Myocardial blood flow occurs during the diastolic phase of the cardiac cycle, because myocardial contraction during the systolic phase impedes myocardial perfusion. Using laser Doppler perfusion technique, we studied the effect of esophageal contraction on the esophageal wall perfusion. Studies were conducted in rats. A laser Doppler probe was anchored to the esophageal wall, and wall perfusion was studied under various experimental conditions. Increase and decrease in the systemic blood pressure induced by different pharmacological agents was associated with the increase and decrease in the esophageal wall perfusion, respectively. Esophageal contractions induced by electrical stimulation of the vagus nerve and electrical stimulation of the muscle directly resulted in a reduction in the esophageal wall perfusion, in a dose-dependent fashion. Esophageal wall perfusion could be monitored by placing the Doppler probe on the esophageal mucosa or on the outside of the esophageal wall. Esophageal contraction impedes entry of blood into the esophageal wall. Future studies may investigate if ischemia of the esophageal wall induced by sustained esophageal contractions/esophageal spasm is the cause of esophageal pain symptoms in humans.

Nutcracker oesophagus: association with chest pain and dysphagia controlling for gastro-oesophageal reflux

BACKGROUND

The association between nutcracker oesophagus, gastro-oesophageal reflux and their symptoms is controversial.

AIM

To evaluate the association of nutcracker oesophagus with chest pain and dysphagia controlling for gastro-oesophageal reflux.

METHODS

From a database of 935 consecutive patients investigated with oesophageal manometry and pH-metry, we selected all patients with nutcracker oesophagus including diffuse and segmental patterns. Patients with normal oesophageal peristalsis served as controls. Symptoms assessment, manometry testing and 24h oesophageal pH monitoring off acid-suppressive medications were performed following a standardized protocol. The associations between nutcracker oesophagus and symptoms were assessed by logistic regression analysis.

RESULTS

Nutcracker oesophagus was found in 60 patients (6.4%), of which 30 had diffuse nutcracker oesophagus and 30 had segmental nutcracker oesophagus. The control group was composed by 656 patients with normal oesophageal peristalsis. Diffuse nutcracker oesophagus was associated with chest pain (odds ratio 4.3; 95% CI 1.9-9.9; P<0.0001) and dysphagia (odds ratio 5.3; 95% CI 2.3-12.2; P<0.0001), whereas segmental nutcracker oesophagus was associated with chest pain (odds ratio 2.8; 95% CI 1.1-6.9; P=0.026), controlling for total oesophageal acid exposure, age, sex and lower oesophageal sphincter (LOS) pressure.

CONCLUSION

This study suggests that both diffuse and segmental nutcracker oesophagus should be regarded as meaningful abnormalities and not mere manometric curiosities.

Non-achalasic motor disorders of the oesophagus

Motor abnormalities of the oesophagus are characterised by a chronic impairment of the neuromuscular structures that co-ordinate oesophageal function. The best-defined entity is achalasia, which is discussed in a separate chapter. Other motor disorders with clinical relevance include diffuse oesophageal spasm, oesophageal dysmotility associated with scleroderma, and ineffective oesophageal motility. These non-achalasic motor disorders have variable prevalence but they could be associated with invalidating symptoms such as dysphagia, chest pain and gastro-oesophageal reflux disease. New oesophageal diagnostic techniques, including high-resolution manometry, high-frequency intraluminal ultrasound and intraluminal impedance, allow (1) better definition of peristalsis and sphincter function, (2) assessment of changes in oesophageal wall thickness, and (3) evaluation of pressure gradients within the oesophagus and across the sphincters that can produce normal or abnormal patterns of bolus transport. This chapter discusses recent advances in physiology, pathophysiology, diagnosis and treatment of non-achalasic oesophageal motor disorders.

A review of the atypical manifestations of gastroesophageal reflux disease

Manifestations of atypical gastroesophageal reflux disease (GORD) are varied, and the presentation of atypical symptoms may occur in the absence of typical symptoms. The most sensitive and specific investigation for GORD is pH monitoring, and its application in atypical disease is utilized throughout this paper as a basis for correlating disease and pathogenesis. The less well-known areas of laryngeal manifestations, particularly chronic hoarseness and globus, are discussed in addition to recent work on orodental manifestations. Well-known areas of cardiac and respiratory manifestations, which include chronic cough and asthma, are also reviewed. Evidence from clinical trials indicates that aggressive anti-reflux therapy in patients with atypical symptoms can be effective. Where appropriate, medical therapy may involve long-term proton pump inhibitor, although further research outlining the roles of other therapies such as surgery is awaited.

Transmural necrosis of the esophagus secondary to acute aortic dissection

A case of transmural ischemic necrosis of the esophagus secondary to aortic dissection is presented. A 66-year-old woman with acute type A aortic dissection underwent total arch replacement with a technique of deep hypothermic arrest and retrograde cerebral perfusion. Postoperatively she had hematemesis, and endoscopic examination revealed circumferential mucosal necrosis and desquamation of the lower esophagus. She died of multiple organ failure on postoperative day 74. Autopsy demonstrated transmural necrosis of the esophagus secondary to ischemia. Ischemia of the esophagus secondary to aortic dissection is extremely rare.

The effect of edrophonium chloride-induced chest pain on esophageal blood flow and motility

BACKGROUND

It is not known to what extent patients with non-cardiac chest pain have esophageal ischemia or motor dysfunction. The aim of this study was to investigate whether chest pain provoked by intravenous edrophonium chloride could be due to esophageal ischemia or to muscular spasm.

METHODS

Sixteen patients with a history of non-cardiac chest pain took part. Ten patients (32-69 years old) who did not develop chest pain with intravenous edrophonium chloride were compared with six patients (50-71 years old) who did develop edrophonium-provoked chest pain. Esophageal motility was monitored manometrically. Changes in esophageal blood flow, assessed as the rewarming time after esophageal cooling, was measured with a thermistor technique.

RESULTS

The esophageal rewarming time after cooling was the same before and during the edrophonium test in both groups. The esophageal contraction amplitudes and contraction duration were significantly increased only in patients with edrophonium-provoked chest pain.

CONCLUSION

Strong esophageal contractions and not a decreased blood flow in the esophageal wall seem to be the cause of chest pain provoked by intravenous edrophonium chloride.

Computerized thermistor technique for indirect studies of esophageal blood flow

The aim of this study was to elaborate on a computerized microthermistor technique for indirect measurement of esophageal blood flow and to investigate if any changes in circulation could be found in patients who are provoked by esophageal acid perfusion of their acid-sensitive mucosa. A thermistor was mounted in a plastic catheter and placed in the esophagus 11 cm above the lower esophageal sphincter. The signal from the thermistor was transmitted to a personal computer. A 15 degrees C water bolus was injected into the catheter in order to cool the esophageal wall at the catheter side hole 1 cm above the thermistor. The reliability of the thermistor test was examined by repeating it in 29 patients. No statistical difference between the two test occasions was found. Twenty-five patients were provoked with an acid perfusion test, 14 of whom had a positive reaction with heartburn. Patients with a positive acid perfusion test had a shorter rewarming time before as well as after provocation than patients with a negative acid perfusion test. It is concluded that this thermistor technique is well suited for measuring intraluminal rewarming rate as an indirect sign of changes in esophageal blood flow. Furthermore, the results indicate that blood supply of the esophageal wall is increased in patients with a positive acid perfusion test.

Clinical use of ambulatory 24-hour esophageal motility monitoring in patients with primary esophageal motor disorders

The development of miniaturized electronic pressure transducers and portable digital data recorders with large storage capacity has made ambulatory monitoring of esophageal motor function over an entire circadian cycle possible. Broad clinical application of this new technology in a large number of asymptomatic normal volunteers and patients with symptoms suggestive of a primary esophageal motor disorder provides new insights into esophageal motor function under a variety of physiologic conditions in health and disease. These studies suggest that ambulatory esophageal motility monitoring allows for a more precise classification of esophageal motor disorders than standard manometry and can identify abnormal esophageal motor patterns associated with nonobstructive dysphagia or noncardiac chest pain. Ambulatory esophageal motility monitoring performed in combination with pH monitoring is currently the most physiologic way to assess esophageal function and has potential to improve diagnosis and management of patients with esophageal motor disorders. Ambulatory 24-h esophageal motility monitoring should become the gold standard for assessing motor function of the esophageal body.

The gastroenterologist's approach to dysphagia

In the gastroenterological diagnostic armamentarium, dysphagia is considered as an important symptom for diseases of the esophagus. Concerning the history of illness, symptoms such as retrosternal pain and heartburn are often associated with gastroesophageal reflux disease. Morphological changes of the mucosa can be diagnosed by flexible endoscopy and radiographic examinations. Investigation with 24-h pH monitoring, manometry, and pharmacological tests is necessary for the diagnosis of functional disorders. Additionally, dysphagia can be associated with multiple internal diseases, including muscular diseases such as dermatomyositis, progressive systemic sclerosis, as well as lupus erythematosus. Difficulties in swallowing associated with hypo- and hyperthyroidism can also be interpreted as muscular lesions. Metabolic disorders such as alcoholism, and diabetes mellitus can be the cause of dysphagia. Increasing importance in the differential diagnosis of dysphagia is attached to infections of the upper GI tract. Especially in immunocompromised patients, infections of Candida albicans, mycobacterias, herpes, varicella zoster, and cytomegaloviruses can produce dysphagia and odynophagia. The differential diagnosis of the "angina-like chest pain" has to differentiate between cardiac disease and a noncardiac genesis. Therefore, besides the cardiac diagnostic investigation, endoscopy, radiography, and manometry are often indicated.

Long-term follow-up of patients initially diagnosed with syndrome X

The clinical course of 30 patients (27 women and 3 men) diagnosed with syndrome X (angina pectoris, positive exercise test and normal coronary arteries) was evaluated during 5-year follow up. Patients were divided at the control examination into 2 groups according to the median value of the heart rate/blood pressure product variation from rest to the first stage of a modified Bruce protocol, as follows: group 1 < or = 1,050 (n = 15) and group 2 > 1,050 mm Hg x beats/min (n = 15). All patients were followed at 6-month intervals during a mean follow-up of 60 +/- 8 months. During follow-up, chest pain was unchanged in 20 patients, decreased in severity and frequency in 9 (7 in group 1, and 2 in group 2), and disappeared in 1 in group 2; 3 patients in group 1 had prolonged episodes of anginal chest pain (> 30 minutes) that needed hospitalization. In group 2, 7 patients developed systemic hypertension, 4 had a progression of exercise-induced left bundle branch block to constant left bundle branch block, and 4 continued to develop rate-dependent block during exercise, but at a reduced heart rate. In the latter 8 patients, left ventricular ejection fraction at rest during follow-up decreased significantly from 61 +/- 6% to 51 +/- 8% (p < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Indications, technique, and clinical use of ambulatory 24-hour esophageal motility monitoring in a surgical practice

The development of miniaturized electronic pressure transducers and portable digital data recorders with large storage capacity has made ambulatory monitoring of esophageal motor function over an entire circadian cycle possible. The broad clinical application of this new technology in a large number of asymptomatic normal volunteers and patients with primary esophageal motor disorders or gastroesophageal reflux disease provides new insights into esophageal motor function in health and disease under a variety of physiologic conditions. In normal volunteers and symptomatic patients, esophageal motor activity increases with both the state of consciousness and eating activity, i.e., from sleep to awake to meal periods. In the normal situation there is a higher prevalence of nonperistaltic esophageal contractions than appreciated on stationary manometry. Compared with standard manometry, ambulatory esophageal manometry provides a more than 100-fold larger database for the classification and quantitation of abnormal esophageal motor function and leads to a change in the diagnosis in a substantial portion of patients with symptoms suggestive of a primary esophageal motor disorder. In patients with nonobstructive dysphagia, the circadian esophageal motility pattern is characterized by an inability to organize the motor activity into peristaltic contractions during meal periods. In patients with noncardiac chest pain, ambulatory motility monitoring can document a direct correlation of abnormal esophageal motor activity with the symptom and shows that the abnormal motor activity immediately preceding the pain episodes is characterized by an increased frequency of simultaneous, double- and triple-peaked, high-amplitude, and long-duration contractions. A long esophageal myotomy can abolish the ability of the esophagus to produce this abnormal motor pattern. In patients with gastroesophageal reflux disease, ambulatory motility monitoring shows that the contractility of the esophageal body deteriorates with increasing severity of esophageal mucosal injury, compromising the clearance function of the esophageal body. These data suggest that ambulatory esophageal motility monitoring allows for a more precise classification of esophageal motor disorders than standard manometry and can identify abnormal esophageal motor pattern associated with nonobstructive dysphagia, noncardiac chest pain, or gastroesophageal reflux. Ambulatory esophageal manometry therefore should replace standard manometry in the assessment of esophageal body function and has potential to improve the diagnosis and management of patients with esophageal motor abnormalities. The combination of ambulatory 24-hour esophageal manometry with esophageal and gastric pH monitoring is currently the most physiologic way to assess patients with functional foregut disorders.

Acid perfusion and edrophonium provocation tests in patients with chest pain of undetermined etiology

During the last five years, 672 patients were referred to our esophageal investigation unit; 110 patients (16.3%) of these presented with chest pain of undetermined etiology (CPUE) alone. Since the nature of this pain is intermittent and rarely present during the diagnostic study, acid perfusion and intravenous edrophonium tests were added as provocative tests after baseline esophageal manometry. Following completion of the motility studies, 24-hr pH study was performed to detect gastroesophageal reflux (GER). Twenty-nine patients (26.4%) had positive acid perfusion (APT) test whereas 26 patients (23.6%) had positive edrophonium test (ET). In the group of patients with positive acid perfusion test, 12/29 (41.3%) had GER, 8/29 (27.5%) had both motility disorder and GER, 2/29 (6.8%) had motility disorder, and 7/29 (24.1%) had normal esophageal motility and 24-hr pH studies. In the other group, 13/26 (50%) had motility disorder and 13/26 (50%) had both motility disorder and GER. There were no significant differences between the two tests as far as reproducibility of symptoms was concerned. We conclude that ATP and ET showed the esophageal origin of CPUE in half of our patients and therefore in a substantial percentage of patients the esophageal origin of chest pain will remain very difficult to prove.

Thoracoscopic long oesophageal myotomy for nutcracker oesophagus: initial experience of a new surgical approach

A thoracoscopic technique is described for the execution of long oesophageal myotomy for nutcracker oesophagus causing odynophagia and non-cardiac chest pain. The technique is based on a multipuncture method and a left thoracoscopic approach. It has been performed on three patients with complete symptomatic relief in the short term, although the follow-up period is short (maximum 12 months). No complications were encountered and discharge from hospital occurred by the fifth day after operation.

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.

The effects of peripheral cold exposure on oesophageal motility in patients with autoimmune rheumatic diseases and Raynaud's phenomenon

The effects of peripheral cold exposure on oesophageal motility were studied in 14 patients with autoimmune rheumatic diseases. They were divided into two groups: 9 with and 5 without Raynaud's phenomenon. The statistical comparison of these two groups did not reveal any difference in the way they manometrically reacted during and after the cold exposure. We conclude that the oesophageal dysfunction in Raynaud's phenomenon may not be of neurogenic origin.

Achalasia, diffuse spasm and non-specific motor disorders

Achalasia is the best understood of the motor disorders described in this chapter. The pathogenesis involves loss of intramural neurones, a process that subsequently results in poor lower sphincter relaxation and atony of the oesophageal body. Treatment is appropriately focused on mechanical or pharmacological alleviation of LOS obstruction. In contrast, the pathophysiology of DOS and the non-specific disorders remains poorly understood. Some of the non-specific disorders, such as the vigorous contraction wave abnormalities (including 'nutcracker oesophagus'), appear closely related to DOS. Treatment for patients with these findings has been based on assumptions about mechanisms of symptom production. The non-specific disorders are common in referred patients with oesophageal symptoms, and the importance of these findings deserves further study. We use a method for categorization of these manometric abnormalities which aids understanding of this difficult area and recommend its more widespread use.

Ambulatory 24 hour intraoesophageal pH and pressure recordings v provocation tests in the diagnosis of chest pain of oesophageal origin

Fifty patients with non-cardiac chest pain underwent 24 hour intraoesophageal pH and pressure recording and provocation tests to determine the relative value of both techniques in establishing the oesophageal origin of the chest pain. Twenty six patients (52%) had at least one positive provocation test: the acid perfusion test was positive related in 18 patients (36%), the edrophonium test in 16 patients (32%), the vasopressin test in five patients (10%), and the balloon distension test (performed in only 20 patients) in one (5%). The 24 hour pH and pressure recording correlated spontaneous chest pain attacks with abnormal motility or gastro-oesophageal reflux in 19 patients (38%). Fourteen of these patients also had at least one positive provocation test. Therefore, 24 hour pH and pressure recordings are only slightly better than a set of provocation tests in identifying the oesophagus as the cause of chest pain (10% diagnostic gain). In the case of oesophageal chest pain, however, 24 hour recording appeared to be the only way to identify the nature of the underlying oesophageal abnormality that caused the spontaneous pain attacks--for example, gastro-oesophageal reflux, motility disorders, or irritability of the oesophagus.

Morphologic characteristics and functional significance of focal fibromuscular dysplasia of small coronary arteries

Focal fibromuscular dysplasia of small coronary arteries is not so rare as it is unrecognized. Although sometimes occurring as an isolated abnormality, it more often accompanies a variety of other lesions including inflammation or infiltration. In this review based on personal study of over 1,000 human hearts, the 3 topics include a description of the morphologic characteristics of the lesion, a discussion of its functional consequences affecting coronary flow, and an iteration of theoretical explanations for its development. The typical lesion is focal in distribution, is comprised of both fibrous and smooth muscle elements, and the histologic organization is one of dysplastic array. Included among the subjects discussed in functional consequences are coronary spasm, coronary reserve, chest pain, electrical instability of the heart, and comments on the role of focal fibromuscular dysplasia of small coronary arteries in hypertension, myocardial hypertrophy and heart failure. Theories as to its development include primary faults of smooth muscle or collagen, and focal abnormalities of clotting or neurovascular relation, but it is likely that the cause is multifactorial.

Recent studies of the pathophysiology and diagnosis of esophageal symptoms

The three main symptoms of esophageal disease or disorder are dysphagia, chest pain, and heartburn. Dysphagia in achalasia is mainly due to a non-relaxing lower esophageal sphincter (LES). The mechanism of dysphagia in diffuse esophageal spasm and related motor disorders is related to a combination of several factors including incomplete LES relaxation, failed or weak peristalsis (pressure less than 30 mmHg in the distal esophagus, and orad positive pressure gradient). Meal manometry and balloon distention may prove to be useful provocation tests. Chest pain of esophageal origin may be due to gastroesophageal reflux and esophageal motility disorders; it may also be a manifestation of an irritable esophagus, in which the esophagus is hypersensitive to various stimuli (chemical, mechanical, ischemic). Esophageal provocation tests may suggest the esophageal origin of the pain but do not give information on the nature of the esophageal disorder. Twenty-four-hour pH and pressure measurements may, however, yield this information. Heartburn and acid regurgitations are the most typical symptoms of gastroesophageal reflux. Transient relaxations of the LES are considered to be an important contributory mechanism of reflux. Absent basal LES pressure is another mechanism, which accounts for about one-fourth of the reflux episodes in patients with severe reflux esophagitis. During long-lasting inappropriate relaxations, swallows often produce deglutitive contraction waves that die out in the upper esophagus, suggesting that reflux often occurs during periods of inhibition of both LES tone and peristaltic esophageal activity.

Regional differences in the vascular response of the canine esophagus to vasodilators

The basal blood flow of the proximal and distal body of the esophagus, and that of the lower esophageal sphincter, and the vascular response of these sites to intravenous infusion of nifedipine (1.0 microgram/kg.min) and isoproterenol (0.1 microgram/kg.min) were studied. The basal blood flow of the mucosa plus submucosa, muscularis propria, and the whole wall was significantly higher in the lower esophageal sphincter than in the proximal or the distal body. Intravenous nifedipine caused a similar decrease in vascular tone of the mucosa and the muscularis propria in all sites of the esophagus. Isoproterenol infusion significantly decreased the vascular tone of the mucosa with columnar epithelium (i.e., mucosa overlying the lower esophageal sphincter), but not of the mucosa with squamous epithelium (i.e., mucosa overlying the body). In the muscularis propria the vasodilatory effect of isoproterenol and nifedipine was significant at all sites, but this effect was greater in the striated muscle of the body than in the smooth muscle of the lower esophageal sphincter (p less than 0.05). Thus, not only do different vasodilators have different effects on the vasculature of the esophagus, but also a single agent may have differing effects on the various sites and layers of this organ.