Normal swallowing

Motor disorders of swallowing

Achalasia

Treating Achalasia

Glossary of Medical Terms

Links

The oesophagus is a long muscular tube measuring 25cms, which connects the back of the throat to the stomach. Food is propelled through the oesophagus by a co-ordinated series of contractions of the oesophageal muscle. These are called peristalsis. The oesophagus has nerve input from two sets of nerves which emerge from the central nervous system:

• the sympathetic nervous system,
• the vagus nerve carrying parasympathetic supply

In addition the gut wall has an intrinsic nervous system (the myenteric plexus). The degree of contraction or relaxation of any part of the oesophagus is due to a complex interplay between these various nervous inputs.

2. Normal swallowing.

   The muscular coat of the oesophagus has two layers. The inner layer is circular and the outer layer is longitudinal. When a person swallows a peristaltic event is triggered. It starts with the longitudinal muscles of the oesophagus contracting in sequence to shorten the oesophagus. A ring like contraction of the circular muscles then sweeps along the oesophagus to propel the bolus of food into the stomach.    BACK TO TOP

    

3. Disorders of oesophageal motor function.

Oesophageal motility disorders comprise any condition whose symptoms, especially difficulty in swallowing (dysphagia) and chest pain, are suspected of being oesophageal in origin. These disorders are classically diagnosed by oesophageal manometry studies, which assess

• the pressure in the lower oesophageal sphincter and the degree of relaxation of the lower oesophageal sphincter.
• the presence of peristalsis (a co-ordinated propulsion of food or fluid) in the oesophageal body and the characteristics of the contraction waves including high or low amplitude, duration, repetitive nature, and the presence of either non transmitted or partly transmitted waves.

Most assessments concentrate on the distal (lower) two thirds of the oesophagus. Normal values on manometry studies have been calculated through the study of large healthy populations ¹.

Other tests which can be useful in making the diagnosis include barium swallow and gastroscopy.

Abnormalities in the motility of the muscle of the oesophagus can lead to symptoms of chest pain and dysphagia (difficulty swallowing). The classification for most disorders of oesophageal motor function is imprecise. Achalasia has a defined and identifiable pathological series of changes associated with it but other motor disorders do not. Chest pain can be associated with any disease of motility of the oesophagus. Patients may initially present to a doctor with what is thought to be angina of cardiac origin.

In addition, a significant proportion of patients with gastro-oesophageal reflux disease may suffer with ‘atypical’ chest pain which presents as angina. It is well recognised that these patients often restrict their lifestyle believing they have heart disease ². These patients often respond to proton pump inhibitor drugs which profoundly suppress production of acid in the stomach.

A problematic feature of patients with oesophageal dysmotility syndromes is that there is an inconsistent association between oesophageal symptoms (such as chest pain), degree of dysmotility and psychological symptoms. In a study of 113 patients with various types of oesophageal dysmotility disorders, those with achalasia and diffuse oesophageal spasm had normal psychometric profiles. In contrast, those with other dysmotility disorders had increased psychological abnormalities including depression. Interestingly, in the entire cohort of patients, the presence of chest pain was closely associated with the presence of psychometric abnormalities ³.

4.    Achalasia.

Achalasia (Latin a= absence, chalus = relaxation) is a disease of unknown cause, which is characterised by an absence of peristalsis in the smooth muscle oesophagus and failed or incomplete relaxation of the lower oesophageal sphincter. A variant of achalasia, called vigorous achalasia, shows the same abnormalities in the lower oesophageal sphincter but vigorous contractions within the oesophageal body ⁴. Achalasia is a particular type of oesophageal dysmotility.

Achalasia is uncommon but not rare and has a prevalence of 10 cases per 100,000 population ⁵. It becomes increasingly common with increasing age ⁶. It is due to degeneration of nerve cells within the myenteric plexus (the nerves within the wall of the oesophagus) ⁷.

The clinical manifestations of achalasia are various. Symptoms are often present for several years before the patient comes to medical attention ⁸. The major symptoms include dysphagia to both solids and liquids, regurgitation, heartburn, weight loss and foul breath. Chest pain is often a major feature in the complex of symptoms. It is often precipitated by eating, can waken the patient at night and may be so severe as to cause decreased food intake and weight loss. If chest pain persists, the presence of the variant vigorous achalasia may be more likely ⁹. In an eighteen-year prospective study of 101 consecutive patients with the diagnosis of new achalasia, 64 reported chest pain ¹⁰. Neither manometric nor radiological findings predicted the occurrence of this retrosternal pain. Patients with chest pain however were significantly younger than those without and they had a shorter duration of symptoms. Treatment with dilatation or surgical myotomy effectively diminished dysphagia but had little effect on the occurrence of retrosternal chest pain ¹⁰. Over a course of a several years however chest pain diminished in most patients and disappeared in the minority of them. This has been interpreted by some people as being due to a decrease in visceral sensitivity (sensitivity to internal stimuli) with increasing age ¹¹.

Weight loss is common in achalasia, but with better diagnostic tests over the past few years leading to earlier diagnosis, patients may have a completely normal weight. Treatment may reverse the weight loss or prevent it entirely.

The degeneration of the nerves causing achalasia cannot be corrected. Treatment is therefore directed at palliating symptoms and preventing complications. This is mainly accomplished by reducing the lower oesophageal sphincter pressure because peristalsis rarely returns with therapy. This can be done with drugs, forceful dilatation and surgical myotomy.

No drugs give long term improvement. Those tried include nitrates, theophylline, calcium channel blockers, particularly nifedipine and botulinum toxin.

Forceful dilatation to a diameter of 30 mm is needed to tear the muscle in the lower oesophageal sphincter and achieve long lasting reduction of sphincter pressure in these patients. Studies suggest resolution of dysphagia in 32-98% of patients with younger patients and those with a shorter duration of symptoms doing less well than older patients ^12-15. If initial success is achieved, only small numbers will need repeat dilatation at a later stage.

Surgical myotomy is associated with good functional improvement in 65-92% of patients ^16;17. Gastroesophageal reflux may occur after surgery in anything up to 52% of patients ¹⁸.

LINKS

You might find the following web sites useful
www.digestive-disorders.co.uk

1. Clouse RE,.Staiano.A. Manometric patterns using esophageal body and lower sphincter characteristics: findings in 1013 patients. Dig Dis Sci 1992;37:289-96.
2. Shrestha S,.Pasricha PJ. Update on noncardiac chest pain. Dig Dis 2000;18:138-46.

3. Song CW, Lee SJ, Jeen YT, Chun HJ, Um SH, Kim CD et al. Inconsistent association of esophageal symptoms, psychometric abnormalities and dysmotility. Am J Gastroenterol 2001;96:2312-6.

4. Textbook of Gastroenterology. Michigan USA: Lipincott Williams and Wilkins, 1999.

5. Mayberry, J. F. and Atkinson, M. Variations in the prevalence of achalasia in Great Briain and Ireland: An epidemiological study based on hospital admissions. Q J Med 237, 67-74. 1987.

6. Mayberry, J. F. and Atkinson, M. Studies of incidence and prevalence of achalasia in the Nottingham area. Q J Med 56, 451-456. 1985.

7. Cassella, R. R., Brown Jr, A. L., Sayre, G. P., and Ellis Jr, F. Achalasia of the esophagus: pathologic and etiologic considerations. Ann Surg 1964; 160: 474-484.

8. Kahrilas PJ. Esophageal motility disorders: current concepts of pathogenesis and treatment. Can J Gastroenterol 2000;3:221-31.

9. Bondi, J. L., Godwin, D. H., and Garrett, J. M. "Vigorous" achalasia. Its clinical interpretation and significance. Am J Gastroenterol 1972; 58, 145-155.

10. Eckardt VF, Stauf B, Bernhard G. Chest pain in achalasia: patient characteristics and clinical course. Gastroenterology 1999;116:1300-4.

11. Nylander DL, Aithal GP, Tanner AR, Dellipiani AW, Dwarakanath DA. Chest pain in achalasia is an age-dependent phenomenon. Gastroenterology 1999;117:1259-.

12. Vantrappen, C. and Janssens, J. To dilate or to operate? That is the question. Gut 1983; 24, 1013-1019.

13. Sanderson, D. R., Ellis Jr, F., and Olsen, A. M. Achalasia of the esophagus: results of therapy by dilation, 1950-1967. Chest 1970; 58: 116-121.

14. Olsen, A. M., Harrington, S. W., Moersch, H. J., and Anderson, H. A. The treatment of cardiospasm: analysis of a twelve year experience. J Thorac Cardiovasc Surg 1951; 22: 164-173.

15. Fellow, I. W., Ogilvie, A. L., and Atkinson, M. Pneumatic diilatation in achalasia. Gut 1983; 24 1020-1027.

16. Okike, N., Paynes, W. S., Neufeld, N. T., Bernatz, P. E., Pairolero, P. C., and Sanderson, D. R. Esophagomyotomy versus forceful dilation for achalasia of the esophagus: results in 899 patients. Ann Thorac Surg 1979; 28: 119-125.

17. Csendes, A., Braghetto, I., Mascaro, J., and Henriquez, A. Late subjective and objective evaluation of the results of esophagomyotomy in 100 patients with achalasia of the esophagus. Surgery 1988; 104: 469-475.

18. Jara, F. M., Toledo-Pereya, L. H., Lewis, J. H., and Muligan, D. J. Long-term results of esophagomyotomy for achalasia of esophagus. Arch Surg 1979; 114: 935-936..

A condition characterised by lack of normal relaxation of the valve at the lower end of the gullet, which should occur during swallowing

Chest pain caused by lack of blood to the heart. This caharacterisically occurs during exertion

An Xray examination using barium to assess the swallowing function

Relating to the heart

Abnormal contraction of the muscular wall of the esophagus causing pain and dysphagia, often in response to regurgitation of acid gastric contents.

A drug used for treating angina, high blood pressure and oesophageal dysmotility syndromes that works by interfering with calcium flow in and out of cells

Difficulty swallowing

Use of specially designed endoscope which allows ultrasound images to be generated from within the gastrointestinal tract. This test gives very high resolution pictures of the anatomy of the gut

Visual examination of interior sections of the body by introduction of an instrument (an endoscope) through the mouth; examples include esophagoscopy, gastroscopy, bronchoscopy. When used unualified, it is often taken to mean gastroscopy

Reating to the stomach

The junction between the oesophagus and stomach

A syndrome due to structural or functional incompetence of the lower oesophageal sphincter, which permits retrograde flow of acidic gastric juice into the oesophagus.

Visual examination of oesophagus, stomach and duodenum by introduction of an instrument (an endoscope) through the mouth

A drug used for angina and sometimes for oesopahgeal dysmotility syndromes

Deficient blood supply to any part of the body

Deficient blood supply to the muscles of the heart which can be associated with pain and death of heart muscle (commonly called a heart attack)

A longer acting drug in the same class as glyceryl trinitrate

Musculature of the gastroesophageal junction that is continuously (tonically) active except during swallowing.

Measurement of the pressure of gases or fluids by means of a manometer.

A plexus of nerve fibers and autonomic cell bodies lying in the muscular coat of the esophagus, stomach, and intestines

Surgical division of a muscle

Group of drugs including isosorbide and glyceryl trinitrate

Pain on swallowing

Abnormal function of the oesophagus in which the normal muscle contractions are altered

Relating to the gullet - swalloing tube that passes between the throat and stomach

A drug that suppresses acid secretion in the stomach, of the proton pump inhibitor class

Pertaining to a division of the autonomic (independent - self governing) nervous system. These nerves cannot be controlled at will

The movement of the intestine or other tubular structure, characterised by waves of alternate circular contraction and relaxation of the tube by which the contents are propelled onward

Potent drugs for suppressing acid secretion in the stomach. They interact with the proton pump mechanism that creates acid in the wall of the stomach

A condition which has the manometric features of achalasia but is due to another cause such as a tumour

The science of mental testing

The study of diagnosis of disease using X-rays and other allied imaging techniques

Pain behind the sternum (breast bone)

Behind the sternum (breast bone)

Pain beneath the sternum (breast bone)

Pertaining to a division of the autonomic (independent - self governing) nervous system. These nerves cannot be controlled at will

The middle part of the spine, behind the chest

Production of a visible image from the use of high frequency sound waves. Echoes of reflected sound are used to buyild up an electgronic image of the various structures of the body

The 10th cranial nerve, which exits from the base of the skull and supplies nerve fibres widely througout the thorasx (chest) and abdomen

A variant of achalasia in which vigorous contractions of the oesopahgeal body are present

Sensitivity to stimuli inside the organs of the body