Achalasia Cardia

Achalasia is a primary oesophageal motility disorder characterised by impaired relaxation of the lower oesophageal sphincter and absent normal oesophageal peristalsis.

It results from degeneration of inhibitory neurons within the myenteric plexus. Food and saliva progressively accumulate above a nonrelaxing gastroesophageal junction, eventually producing oesophageal dilatation and tortuosity.

High resolution manometry defines three clinically useful subtypes:

• Type I: absent contractility with minimal pressurisation.
• Type II: absent contractility with panesophageal pressurisation.
• Type III: premature or spastic distal oesophageal contractions.

Type II responds particularly well to all definitive therapies. Type III usually requires a longer myotomy and is particularly suited to peroral endoscopic myotomy.

Progressive dysphagia to both liquids and solids from early in the disease is characteristic.

Other features include regurgitation of undigested food, nocturnal cough, aspiration, chest pain and weight loss.

Patients may adopt manoeuvres such as drinking water, standing or extending the neck to assist oesophageal emptying.

Marked or rapid weight loss, older age at onset or unusually rapid progression should raise concern for pseudoachalasia from malignancy at the gastroesophageal junction.

Upper gastrointestinal endoscopy: excludes mechanical obstruction and malignancy and may demonstrate retained food with a tight gastroesophageal junction.

Timed barium oesophagram: demonstrates impaired emptying and distal tapering with the classical bird beak appearance.

High resolution manometry: diagnostic standard and defines the achalasia subtype.

Patients with suspected pseudoachalasia require additional cross sectional imaging and endoscopic evaluation.

Definitive therapy disrupts the lower oesophageal sphincter. No available treatment restores normal peristalsis.

Pneumatic dilation is performed using graded balloons, commonly beginning with a 30 mm balloon, followed by 35 mm and 40 mm dilation if symptoms persist. Perforation is the major complication and patients require access to surgical rescue.

Laparoscopic Heller myotomy divides the distal oesophageal circular muscle and extends across the gastroesophageal junction onto the proximal stomach. A partial fundoplication, commonly Dor or Toupet, should accompany surgical myotomy because myotomy alone produces substantial postoperative reflux.

Peroral endoscopic myotomy provides similar sphincter disruption without abdominal incisions and allows a substantially longer proximal myotomy. It is especially effective in type III achalasia. The major tradeoff is a higher incidence of postoperative gastroesophageal reflux than Heller myotomy combined with fundoplication.

Type I and II disease can be treated effectively with pneumatic dilation, Heller myotomy or peroral endoscopic myotomy.

Type III disease generally favours peroral endoscopic myotomy or a suitably extended surgical myotomy.

For patients too frail for definitive therapy:

Botulinum toxin 100 units can be injected endoscopically into the lower oesophageal sphincter, typically divided among four quadrants. Benefit is usually temporary and repeated injections may cause fibrosis that complicates subsequent definitive treatment.

Nitrates and calcium channel blockers provide inconsistent short duration relief and are reserved for patients unable to undergo definitive treatment.

Treatment failure or recurrent dysphagia requires reassessment with endoscopy and timed barium imaging. Pneumatic dilation, repeat myotomy or peroral endoscopic myotomy can be used after previous treatment failure.

End stage massively dilated, sigmoid shaped oesophagus with persistent obstruction, recurrent aspiration and failure of appropriate myotomy may ultimately require oesophagectomy.