Esophageal spasm: a common cause of spontaneous precordial pain

Fifty-eight consecutive patients were investigated for spontaneous chest pain without symptoms of effort angina, previous myocardial infarction or other signs of cardiac disease, to determine the incidence of oesophageal spasm. The character of the chest pain, its context and the results of resting ECGs were analysed. An ECG recorded during chest pain was available in 23 cases and exercise stress testing was performed in 43 cases. Coronary angiography was carried out in all patients. The coronary arteries were normal or showed little change in 44 patients. Further investigations were ordered: oesophageal manometry (42 cases), echocardiography 44 cases) and ergometrine provocation tests (44 cases). The patients were then divided into 4 groups: 23 patients (40 p. 100) with coronary artery disease; either atheroma (14 cases) or spasm (9 cases); 8 patients (13,5 p. 100) with non-coronary cardiac pathology (myocardial hypertrophy or mitral valve prolapse); 15 patients (26 p. 100) with oesophageal spasm alone; 12 patients (20,5 p. 100) with no obvious organic disease. Often simulating spontaneous angina, clinically and electrocardiographically, oesophageal spasm may sometimes be distinguished (6 out of 15 cases) by the finding of painful dysphagia on swallowing ice-cold liquid. The condition is confirmed by oesophageal manometry which shows abnormalities of oesophageal contraction. In addition, 13 out of 15 patients in our series had hypotonia of the gastro-oesophageal sphincter. Dyskinetic phenomena and this hypotonia should be taken into consideration in the treatment of this condition.     

Early increase of lower oesophageal sphincter pressure after band ligation of oesophageal varices in cirrhotics: an intriguing phenomenon

AIM: We conducted a prospective, randomized comparison of endoscopic variceal ligation, sclerotherapy and metoclopramide injection in order to evaluate their early effect on lower oesophageal sphincter pressure. METHODS: Twenty-six patients with established cirrhosis and an episode of variceal bleeding controlled by one session of endoscopic therapy were randomized to undergo an oesophageal manometry. The patients' lower oesophageal sphincter pressure was evaluated, prior to and immediately after a single session of ligation (n = 10), a single session of sclerotherapy (n = 8) or a bolus injection of 20 mg metoclopramide hydrochloride (n = 8). RESULTS: Ligation produced a higher early increase in lower oesophageal sphincter pressure (from 12.3 +/- 2.3 to 27.8 +/- 3.0 mmHg) as compared with sclerotherapy (from 13.6 +/- 2.5 to 22.4 +/- 4.5 mmHg) or metoclopramide injection (from 14.6 +/- 3.2 to 22.5 +/- 2.9 mmHg); (P = 0.0001). CONCLUSION: Our data indicate that ligation of oesophageal varices produces an early increase in lower oesophageal sphincter pressure in cirrhotic patients.     

Mechanisms of acid reflux associated with cigarette smoking.

Studies were done to evaluate the lower oesophageal sphincter function of chronic smokers compared with non-smokers and to ascertain the acute effects of smoking on the sphincter and the occurrence of acid reflux. All subjects (non-smokers, asymptomatic cigarette smokers, and smokers with oesophagitis) were studied postprandially with a lower oesophageal sphincter sleeve assembly, distal oesophageal pH electrode, and submental electromyographic electrodes. The two groups of cigarette smokers then smoked three cigarettes in succession before being recorded for an additional hour. As a group, the cigarette smokers had significantly lower lower oesophageal sphincter pressure compared with non-smokers but the sphincter was not further compromised by acutely smoking cigarettes. Cigarette smoking did, however, acutely increase the rate at which acid reflux events occurred. The mechanisms of acid reflux during cigarette smoking were mainly dependent upon the coexistence of diminished lower oesophageal sphincter pressure. Fewer than half of reflux events occurred by transient lower oesophageal sphincter relaxations. The majority of acid reflux occurred with coughing or deep inspiration during which abrupt increases in intra-abdominal pressure overpowered a feeble sphincter. We conclude that cigarette smoking probably exacerbates reflux disease by directly provoking acid reflux and perhaps by a long lasting reduction of lower oesophageal sphincter pressure.     

Monitoring of upper oesophageal sphincter pressure in children.

In children technical limitations of upper oesophageal sphincter manometry have restricted investigation to the pull through technique under sedation. In this study we have used an adapted sleeve manometric technique for upper oesophageal sphincter monitoring in unsedated children and determined the influence of the state of arousal on upper oesophageal sphincter pressure. Twenty six children aged 3 to 42 months (median 17.5 months), who were referred for evaluation of oesophageal motor function, were studied with dual sleeve manometric assemblies which monitored upper and lower oesophageal sphincter pressures simultaneously. Pharyngeal, oesophageal body, and gastric pressures were also monitored with seven perfused side holes. Recordings were made for four hours after a meal and were technically successful in 24 children. The child's state of arousal was scored every 12th minute as follows: (A) resting, eyes closed, (B) resting, eyes open, (C) moving but comfortable, (D) restless and uncomfortable, (E) crying. In 67% of the 12 minute samples the children showed good adaptation to the procedure (arousal states A to C). There was a highly significant difference in upper oesophageal sphincter pressure between each of the arousal states (p less than 0.0001), being lowest in category A at (mean (SD) 18.1 (10.3) mmHg and highest in category D 55.7 (13.2) mm Hg. Abrupt changes in the state of arousal were associated with equally abrupt changes in upper oesophageal sphincter pressure. The state of arousal of unsedated children has an important influence on upper oesophageal sphincter pressure. It is essential that this factor is controlled for in any studies of upper oesophageal sphincter tone in children. The sleeve technique is capable of monitoring upper oesophageal sphincter motility for prolonged periods in unsedated children.     

Motor activity of the distal oesophagus and gastrooesophageal reflux.

The relationship between intraoesophageal pH value and motor activity of the lower oesophageal body and sphincter was investigated by simultaneous evaluation of intraluminal pressure and pH in 13 patients complaining of heartburn and regurgitation. One hundred and thirty one episodes of gastro-oesophageal reflux were recorded. One hundred and eighteen (90.1%) were preceded by a swallow (one to 12 seconds), 13 reflux episodes (9.9%) were not preceded by a swallow. Gastro-oesophageal refluxes preceded by swallow were accompanied by an equal number of normal and abnormal primary peristaltic sequences and, while recording at level of the lower oesophageal sphincter, occurred during inhibition of the sphincter. Frequency of abnormal primary peristalsis increased (p less than 0.01) during periods of low intraluminal pH (less than 5.0). An increase of at least 0.5 U in intraluminal pH occurred with 45.2% of normal primary peristalsis, 29.3% of abnormal primary peristalsis, 4.3% of secondary peristalsis, 3.5% of non-peristaltic contractions. The results of this study indicate that in patients with symptoms of reflux oesophagitis, gastro-oesophageal reflux appears to be related to swallow-induced lower oesophageal sphincter inhibition and not related to abnormal motor activity of the distal oesophageal body where an increased frequency of abnormal primary peristalsis appears to occur during low intraluminal pH and primary peristalsis appears to be the most important mechanism of oesophageal clearing.     

Is there a biochemical basis for lower oesophageal sphincter (LOS) resting pressure?

Myosin plays a fundamental role in the contraction of muscle cells. Some structural differences of this protein are related to the different physical properties of muscle--that is, speed of shortening. The typical myosin protein has a molecular weight of 460 000 daltons and is made up of six subunits: two heavy chains (200 000 daltons each) and two pairs of light chains (LC) weighting 15 000-25 000 daltons each (LC1 and LC2). Myosin was extracted from six specimens of human oesophagus in order to find out whether any biochemical differences exist between the oesophageal body and the lower oesophageal sphincter, to account for their different properties. Myosin was examined by two dimensional gel electrophoresis. Peptide mapping of myosin heavy chains was obtained by carrying out enzymatic digestion during the electrophoretic run. A quantitative difference between LC1 of the oesophageal body and the lower oesophageal sphincter was found in the circular fibres, thereby suggesting that two populations of muscle fibres exist in the inner coat of the oesophagus. The presence of more than one type of myosin strongly implies functional differentiation of the two specialised zones.     

Current trends in the management of achalasia

Despite the recent advances in the understanding of the pathophysiology of achalasia, aetiology remains obscure and this primary oesophageal motor disorder is still considered "idiopathic" in nature. As a consequence, the therapeutic approach remains palliative. Since there is little or no chance of improving the motor abnormalities of the oesophageal body, treatment of achalasia is aimed at symptomatic relief of functional lower oesophageal sphincter obstruction. Pharmacologic treatment induces only a limited and brief improvement. It may be used to treat early cases of achalasia without significant oesophageal dilatation and to manage patients exhibiting some but not all the characteristics of achalasia (e.g. transitional forms). In any event, drug therapy should be seen as a short-term measure and be considered as an alternative only in patients unfit to undergo pneumatic dilatation or surgery. Pneumatic dilatation and surgical myotomy (now increasingly carried out through a minimally invasive approach) remain, therefore, the two main approaches which guarantee long-lasting symptomatic relief. Unfortunately, both pneumatic dilatation and Heller cardiomyotomy are only palliative as neither reliably reverses oesophageal aperistalsis not corrects the incomplete postdeglutition relaxation of the lower oesophageal sphincter. They do, however, improve symptoms by lowering lower oesophageal sphincter pressure thus enhancing oesophageal emptying by gravity. Recently a third approach, consisting in perendoscopic injection of botulinum toxin into the lower oesophageal sphincter is gaining acceptance. Indeed, more endoscopists are finding this kind of treatment attractive because it does not carry the risk of perforation that can occur with pneumatic dilatation. However, since symptomatic improvement with botulinum toxin only lasts a few months, either repeated injections are required or the patient must be switched to other therapy. There may be, however, subsets of patients for whom BoTox injection is the preferred approach. They probably include elderly patients or patients with multiple medical problems who are poor candidates for more invasive procedures as well as those unwilling to have either surgery or pneumatic dilatation. Future approaches to achalasia may markedly change from the suggested algorithm depending on the long-term efficacy and safety as well as cost analysis of BoTox injection and of minimally invasive surgery.     

Effect of stress on oesophageal motor function in normal subjects and in patients with the irritable bowel syndrome.

Stress can modulate the motor function of the stomach, small bowel, and colon in healthy subjects, and of the small bowel and colon in patients with the irritable bowel syndrome (IBS). The effect of stress on oesophageal motility in eight healthy subjects and in eight IBS patients was studied, using two pressure transducers positioned just above the lower oesophageal sphincter and 5 cm proximally. Stressors were: a video arcade game, delayed audio feedback, and hand immersion in cold water. Each stress period was followed by five swallows of water. Frequency and amplitude of oesophageal contractions and the number of simultaneous and multipeaked contractions were manually counted for each stress period and compared to the preceding rest period. Frequency of contractions (per minute) tended to decrease during stress periods, but achieved significance only with the video arcade game in the control group (2.0 (0.6) v 1.2 (0.4); p less than 0.01). No other trend was evident in either control or IBS patients. No abnormalities of oesophageal body function were recorded in IBS patients either in basal conditions, or under stress. Unlike the more complex motor programmes elsewhere in the gut, the preprogrammed nature of oesophageal peristalsis is not modulated by stress.     

Evidence for the 'paradox' association between hypertensive lower esophageal sphincter and gastroesophageal reflux disease

There are several studies suggesting the paradoxical simultaneous presence of hypertensive lower oesophageal sphincter and gastroesophageal reflux disease. We present a case of a 22-year-old male patient who was examined in our outpatient clinic with oesophageal food bolus impaction during a meal, severe chest pain and drooling. Manometry revealed a hypertensive lower esophageal sphincter pressure (resting pressure 35 mmHg) and pHmetry revealed a DeMeester score > 14.72 (43.27). Six months after therapy with lansoprazole, manometry revealed a normal lower oesophageal sphincter (resting pressure 14 mmHg) and the DeMeester score was < 14.72 (5.89). The patient is now asymptomatic. This report is the only published case which exhibits the normalization of lower oesophageal pressure 6 months after gastroesophageal reflux disease management with lansoprazole, thus proving and establishing the above 'paradox'.     

Nervous control of distension-induced relaxation of the porcine lower oesophageal sphincter.

The mechanisms involved in the relaxation of the lower oesophageal sphincter induced by distension of the oesophagus and different parts of the stomach, were studied in an anaesthetized porcine model. A computer technique was developed allowing on-line digitizing of lower oesophageal sphincter (sleeve device) and intragastric pressures. Basal sphincter tone was slightly reduced by truncal vagotomy, an effect which seemed to be reversed by sectioning of the vagosympathetic trunks in the neck. Balloon distension of the body of the oesophagus, relaxed the sphincter irrespective of the denervation procedures carried out. Distension of the whole stomach with increasing amounts of air induced a dose-dependent relaxatory lower oesophageal sphincter response, which was also closely associated with the subsequent increases in intragastric pressure. Denervation procedures did not alter this dose-response relationship. The importance of intramural mechanisms was illustrated by the abolition of distension-induced effects in most animals studied after transection of the gastro-oesophageal junction distal to the sphincter. Balloon distension of the antrum elicited a smaller but significant sphincter relaxation, but the mechanisms behind this response seemed to be more complex than after insufflation of air.     

Manometric findings in adult eosinophilic oesophagitis: a study of 12 cases

OBJECTIVE: To describe the manometric findings detected in adult patients with dysphagia that were diagnosed of eosinophilic oesophagitis, and to compare with the cases of eosinophilic infiltration of the oesophagus reported in the literature. PATIENTS AND METHODS: We present 12 adult patients diagnosed as suffering from this disorder in our department in a 1.5-year period, according to histological criteria and discarding any other cause of eosinophilic infiltration of the oesophagus. Stationary oesophageal manometry using a hydropneumocapillary perfusion system was performed in every case. The recommendations of the Spanish Group of Digestive Motility were followed for the interpretation of the results. In seven patients who presented motor disorder in manometric evaluation, treatment with steroid oesophageal lavage using fluticasone propionate was carried out and these patients were subsequently re-evaluated. RESULTS: All patients were young predominantly men, and the first endoscopic examination showed regular concentric stenosis or a 'ring oesophagus'. Six patients had a severe nonspecific oesophageal motor disorder characterized by up to 80% of nontransmitted or very low-amplitude waves in the lower two-thirds of the organ. Three patients presented a manometric disturbance characterized by hyperkinetic peristaltic waves in distal oesophageal third. One patient had an alteration of the oesophageal motor dynamics characterized by 80% of deglutory complexes formed by a primary simultaneous wave in the two lower oesophageal thirds followed by a secondary peristaltic wave in 50% of cases that had a normal duration and amplitude. The remaining two patients had normal oesophageal motility. The upper oesophageal sphincter showed no alterations, and the manometric evaluation of the lower oesophageal sphincter tone proved normal in 10 patients, with slight hypotension in two cases. In seven of the nine patients who presented an oesophageal motor disorder, treatment with steroid oesophageal lavage using fluticasone propionate was administered and a new oesophageal manometry was performed afterwards, in which the motor disorder was clearly improved as soon as dysphagia, endoscopic lesions and histopathologic alteration disappeared. DISCUSSION: In the literature, 61 cases of eosinophilic infiltration of the oesophageal mucosa subjected to oesophageal manometric study had been described, and 60.6% of them showed evidence of different types of manometric alterations, mainly with spastic or hypercontractility characteristics. Although six of our cases showed very deficient peristalsis with very low-amplitude or nontransmitted waves, and in another three high-amplitude peristaltic waves were recorded. Motor disorders improved parallel to the disappearance of the eosinophilic infiltration of the mucosa. These data suggest that motor disorders in eosinophilic oesophagitis are a consequence of eosinophil infiltration of the oesophagus and should be considered in the differential diagnosis of dysphagia. These manometric alterations could be considered as primary nonspecific disorders and included in the 'ineffective oesophageal motility' group.     

Functional relationships between cricopharyngeal sphincter and oesophageal body in response to graded intraluminal distension.

Responses of the cricopharyngeal sphincter to graded intraluminal distension were studied in order to determine its response threshold and to define the functional relationship between the sphincter and oesophageal body. Nine normal subjects underwent manometric study using a multilumen tube with an attached inflatable balloon sited 10 cm below the sphincter. Sphincteric and oesophageal motor responses to six graded balloon inflations were recorded in each subject. The sphincter responded to distension with increasing rise in pressure, from a median value of 42.5 mmHg at lowest levels of distension to 95 mmHg at maximal tolerated distension. Non-swallow related contractile activity was stimulated in the oesophageal body proximal to the distension and increased in quantity as inflation progressed. Distal propagation of this secondary activity was progressively inhibited with increasing distension. These interrelated changes thus show the normal upper oesophageal clearance responses to intraluminal distension. It is suggested that their more widespread application, in addition to standard manometric techniques, might provide a more rational evaluation of those patients suspected to have impaired oesophageal clearance, but in whom standard manometry is non-diagnostic.     

Prokinetics and reflux: a promise unfulfilled.

Gastro-oesophageal reflux disease (GORD) has been described as a motility disorder of the upper gastrointestinal tract. Disturbances of lower oesophageal sphincter function, lower oesophageal body motility, oesophageal clearance and gastric emptying are well accepted. Cisapride improves most of these but its clinical benefits have been relatively modest. Some recent studies have indicated that the improvements achieved with cisapride may be less marked than originally thought. Furthermore, the agent has no effect on transient lower oesophageal sphincter relaxations, nor on other important factors influencing gastro-oesophageal junction competence, such as the external sphincter function of the diaphragmatic crus and mechanical influences such as lower oesophageal sphincter length exposed to intra-abdominal pressure changes. More potent, specific and predictable prokinetic agents would be welcome, but are unlikely to be effective as single agents across the range of GORD. There is certainly a need for such agents, including cisapride, as adjuncts to acid suppression in patients who fail to respond to the latter.     

Mechanisms underlying the antireflux action of fundoplication.

The effect of fundoplication on patterns of gastro-oesophageal reflux and the underlying motor mechanisms were investigated in 18 patients with symptomatic reflux. Oesophageal motility and pH were recorded concurrently after a standard meal. Studies were performed preoperatively and from 5 to 27 months after surgery. Fundoplication virtually eliminated reflux in all but three patients. Control of reflux was associated with a 50% fall in the number of transient lower oesophageal sphincter relaxations, a fall in the proportion of transient lower oesophageal sphincter relaxations accompanied by reflux from 47% to 17%, and an increase in the mean residual pressure at the gastro-oesophageal junction during swallow induced lower oesophageal sphincter relaxation from 0.7 mm Hg to 6.0 mm Hg. Basal pressure at the gastro-oesophageal junction rose from 10.9 mm Hg to 14.5 mm Hg, however, there was no correlation between postoperative reflux and basal gastro-oesophageal junction pressure. These findings suggest that the anti-reflux effects of fundoplication result from changes in the mechanical behaviour of the gastro-oesophageal junction that result in incomplete abolition of the high pressure zone during lower oesophageal sphincter relaxation, and reduced triggering of transient lower oesophageal sphincter relaxations.     

24-H pharyngeal pH monitoring in healthy volunteers: a normative study

BACKGROUND: Gastropharyngeal reflux has been associated with disorders of the upper and lower airways. It may be shown by pharyngeal pH-metry, but reports on normality in healthy volunteers are scarce. No definite consensus has been reached considering the upper limit of normality (ULN). The aim of the present study was therefore to quantify the occurrence of pharyngeal acid exposure (pH < 4) in healthy volunteers and, further, to examine its relation to acid exposure of the oesophagus and oesophageal motility and its occurrence in relation to age, sex, and body position. METHODS: Forty healthy volunteers underwent ambulatory 24-h pH-metry, using antimony electrodes positioned 2 cm above the upper oesophageal sphincter and 5 cm above the lower oesophageal sphincter on the basis of manometry. Technical artefacts were excluded before calculation of all results. RESULTS: Gastropharyngeal reflux occurred in most healthy volunteers without any significant relation to age, sex, or body weight. Pharyngeal acid reflux occurred mainly in the upright position. The ULN for pharyngeal acid exposure time was assessed to 0.9% (0.2% after exclusion of mealtimes). The ULN for the number of acid events in the pharynx was 18 (6.1). The corresponding ULNs for the oesophagus were 7% and 84. CONCLUSION: Gastropharyngeal reflux may be effectively monitored by ambulatory pH-metry. The present study provides reference limits, a prerequisite for evaluating the pathophysiologic importance of the phenomenon.     

Control of belching by the lower oesophageal sphincter.

The mechanism that controls venting of gas from the stomach into the oesophagus was studied manometrically in 14 healthy subjects. The stomach was distended abruptly with one litre of carbon dioxide. Gas reflux was characterised by an abrupt increase in basal oesophageal body pressure to intragastric pressure. Reflux of gas from the stomach into the oesophagus occurred during transient lower oesophageal sphincter relaxations that generally had a pattern distinctly different from swallow-induced lower oesophageal sphincter relaxation. Thus, at the onset of an episode of gas reflux lower oesophageal sphincter pressure had relaxed to 3 mmHg, or less, in 96% of instances. After gas loading of the stomach the prevalence of gas reflux was significantly less when the subjects were supine (1.2/10 min) than when they were sitting (6.8/10 min) (p less than 0.001). The lower oesophageal sphincter relaxations associated with most episodes of gas reflux had a distinctive pattern that resembled those of the lower oesophageal sphincter relaxations associated with acid gastro-oesophageal reflux.     

Gender variation in oesophageal motor function: Analysis of 129 healthy individuals

BackgroundOesophageal manometry is the standard for diagnosis of oesophageal motor disorders. Minimal data exist assessing the effect of gender on normal oesophageal manometry values.AimEvaluate the impact of gender on normal oesophageal manometry values.MethodsHealthy volunteers were recruited from the Jacksonville metropolitan area. Exclusion criteria were symptoms suggestive of oesophageal disease, medication use or concurrent illness that could affect oesophageal manometry. All underwent oesophageal manometry using a solid-state system with wet swallows.ResultsSixty-three males and 66 females were enrolled. All completed oesophageal manometry without difficulty. Resting lower oesophageal sphincter pressure, distal oesophageal contraction duration and distal oesophageal body contraction amplitude values were significantly higher in females while distal oesophageal body contraction velocity was significantly lower in females (p < 0.05). No differences were seen in other oesophageal manometry parameters.ConclusionSignificant gender differences exist in normal oesophageal manometry. Gender-specific reference values for oesophageal manometry are needed for accurate diagnosis of oesophageal motility disorders.     

Is ineffective oesophageal motility associated with reflux oesophagitis?

OBJECTIVE: To evaluate the association between ineffective oesophageal motility and reflux oesophagitis controlling for hiatal hernia, hypotensive lower oesophageal sphincter and male sex in patients with gastro-oesophageal reflux disease. METHODS: A total of 387 patients with reflux disease (mean age, 46 years, 42% men) were consecutively selected from a database. All patients underwent upper endoscopy, oesophageal manometry and 24 h oesophageal pH-metry in accordance with a standardized protocol. Reflux disease was confirmed either by endoscopy (oesophagitis grade I-IV according to Savary-Miller) or by pH-metry (increased acid exposure). Hiatal hernia was diagnosed endoscopically, whereas ineffective oesophageal motility and hypotensive lower oesophageal sphincter were characterized during manometry testing. The association between ineffective oesophageal motility and reflux oesophagitis was assessed by logistic regression analysis. RESULTS: A total of 166 patients with oesophagitis (mean age 45 years, 49% men) and 221 without oesophagitis (mean age 46 years, 37% men) were present. Prevalences of ineffective oesophageal motility, hiatal hernia, hypotensive lower oesophageal sphincter and male sex were significantly higher in patients with oesophagitis compared with those without oesophagitis (P<0.05). Ineffective oesophageal motility was independently associated with oesophagitis after multivariate logistic regression analysis (odds ratio=1.68; 95% confidence interval=1.04-2.70). CONCLUSION: Ineffective oesophageal motility is associated with reflux oesophagitis, independently of hiatal hernia, hypotensive lower oesophageal sphincter and male sex.     

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.