Significant symptoms are more often due to the coexisting motor disorder than to the diverticulum itself
T.P.J. Hennessy (Dublin)
In the majority of reported series, more than 50 p. cent of epiphrenic diverticula are associated with a motility disorder and in Debas'  study 62 p. cent of patients demonstrated a specific motor disturbance and a further 15 p. cent had esophageal motor incoordination. The most frequently encountered specific motor disorders are a hypertonic lower esophageal sphincter, diffuse esophageal spasm or achalasia. Between 10 and 15 p. cent of patients have a normal motor pattern and most of these have a hiatus hernia. Hypertrophic circular muscle is regularly present in the lower esophagus distal to the diverticulum. Esophagitis and stricture may accompany the hiatus hernia. Manometric evaluation is an essential part of the investigation of these patients and 24 hour pH assessment must be carried out to assess the degree of gastroesophageal reflux.
Most epiphrenic diverticula are pulsion in type with mucosal and submucosal layers and few, if any, muscular fibers, implying an underlying motility disorder. A congenital type has also been described . The existence of a complete muscular wall is regarded as indicating a congenital origin and a diverticulum containing ectopic pancreatic tissue in its wall was regarded as congenital by Baar and d'Abreu . A familial incidence involving a father and two of his children with multiple diverticula has also been described .
Pulsion diverticula are induced by high intra-luminal pressures such as occur in diffuse esophageal spasm. Higher than normal intra-luminal pressures may be recorded in the resting state in patients with achalasia, and very high pressures may be generated after eating (figure /). In patients with gastro-esophageal reflux it has been suggested that the reflux induces muscular spasm in the esophagus and that the consequent generation of high intra-luminal pressure is responsible for the appearance of the diverticulum. Whether an area of muscular weakness in the esophageal wall is a necessary adjunct is not known.
Figure 1. 2 channel recording of ambulatory manometry during eating showing elevation of the baseline.
Epiphrenic diverticula have a globular appearance with a wide fundus and a narrow neck and are likely to retain food debris and secretions because of this. Nevertheless, approximately one third of patients with epiphrenic diverticula are asymptomatic. Most large diverticula, however, give rise to a variety of symptoms.
The symptoms most frequently associated with epiphrenic diverticula are retro-sternal pain, dysphagia and regurgitation. Anorexia and weight loss may also occur and halitosis may be an obvious symptom. Any or all of these symptoms may be found in association with esophageal motor disorders. Severe retrosternal pain is particularly associated with dysmotility, and Debas  noted that all patients in his series with a primary motor disorder complained of chest pain. Diffuse
esophageal spasm and vigorous achalasia are most likely to give rise to significant chest pain. Severe pain is seldom a feature of diverticula alone. Dysphagia, weight loss and regurgitation are common symptoms of achalasia and halitosis due to the retention of partially decomposed food in the esophagus may also be present. A combination of dysphagia, weight loss and severe substernal pain is more characteristic of diffuse esophageal spasm and is not usually accompanied by regurgitation or halitosis. Similar symptoms may occur in the presence of a hypertonic lower esophageal sphincter.
Retrosternal pain, dysphagia and regurgitation accompany gastroesophageal reflux. However, if a diverticulum is large enough to compress and displace the esophagus it may, even in the absence of a motility disorder, reproduce most of these symptoms with dysphagia, regurgitation, weight loss and halitosis. Aspiration into the bronchial tree may give rise to fits of coughing and dyspnoea particularly at night time when the patient is recumbent and asleep and may ultimately lead to pneumonia, lung abscess and bronchiectasis. Such respiratory problems may be due to a large diverticulum causing esophageal obstruction or to a motor disorder, most likely achalasia.
Although anaemia may occur with achalasia this is usually nutritional in type and haematemesis if it occurs is either due to ulceration in the diverticulum or a carcinoma which has developed in the diverticulum or in association with achalasia.
Although many epiphrenic diverticula are asymptomatic and require no treatment it is of the utmost importance to identify accurately the associated pathology when symptoms are severe enough to warrant surgery. If significant reflux is present anti-reflux surgery should accompany excision of the diverticulum. In the presence of a primary motor disorder a long myotomy should be added to the diverticulectomy. There is some risk of fistula formation or persistent symptoms if the myotomy is omitted .
In summary, symptoms accompanying epiphrenic diverticula are more often due to the coexisting motor disorder than the diverticulum per se. Much less frequently they are due to an associated hiatus hernia with gastroesophageal reflux and this may be due to the reflux or a secondary motor disorder. Rarely symptoms are due to retention of contents and esophageal obstruction in a large dependent diverticulum.