Achalasia Type 2

Achalasia type II is the manometric subtype with impaired lower oesophageal sphincter relaxation, absent peristalsis and panoesophageal pressurisation in at least 20% of swallows.

Chicago classification: integrated relaxation pressure over 15 mmHg, 100% failed peristalsis, panoesophageal pressurisation (over 30 mmHg) in 20% or more of swallows.

Represents the most common subtype (about 50 to 60%) and has the best prognosis, with response to all treatments, in particular pneumatic dilation and POEM.

Mechanism: early disease with preserved longitudinal muscle contraction compressing a non dilated oesophagus.

May progress to type I with oesophageal dilatation if untreated.

Complications are as for achalasia: aspiration, weight loss, squamous cell carcinoma.

• Dysphagia for solids and liquids, regurgitation, chest pain in 40% (less than type III), weight loss, nocturnal cough.

• Oesophagus usually less dilated at presentation.

Differential: pseudoachalasia, eosinophilic oesophagitis, scleroderma, Chagas disease.

• High resolution manometry: panoesophageal pressurisation with raised integrated relaxation pressure.
• Barium oesophagram: bird beak with a column of barium retention, minimal dilatation.
• Upper endoscopy with biopsy to exclude mimics; endoscopic ultrasound for pseudoachalasia suspicion.
• Timed barium oesophagram (column height after 1 and 5 minutes) to quantify emptying.
• EndoFLIP: reduced distensibility index at the lower oesophageal sphincter.

• All main therapies are effective (success 90 to 100% in type II).
• Pneumatic dilation (graded 30, 35, then 40 mm) with excellent response in type II (about 90% at 1 year, 60 to 70% at 5 years).
• Peroral endoscopic myotomy: success over 95% at 2 years; post procedure reflux and need for PPI.
• Laparoscopic Heller myotomy with partial fundoplication: success 90 to 95%.
• Botulinum toxin 100 units for frail patients (short term).
• Medical therapy (nifedipine, nitrates) as a bridge.
• PPI after POEM; surveillance of reflux oesophagitis, Barrett oesophagus.
• Repeat treatment if recurrent symptoms (Eckardt score over 3), with timed barium oesophagram.
• Squamous cell carcinoma surveillance debated.