What are the stages of achalasia and their respective treatments?

Achalasia Stages and Treatment

Achalasia is classified into three distinct subtypes (Types I, II, and III) based on high-resolution manometry findings, with Type II having the best treatment response, Type I intermediate, and Type III requiring specialized management with extended myotomy. 1

Classification of Achalasia Subtypes

The three subtypes are defined by esophageal body pressurization patterns on high-resolution manometry (HRM):

• Type I (Classic/Decompensated): Characterized by absent contractility and minimal esophageal pressurization, representing a decompensated, dilated esophagus 1

• Type II (Compression): Features pan-esophageal pressurization with swallows, presumed to be the precursor stage to Type I, and represents the most common presenting subtype 1

• Type III (Spastic/Vigorous): Associated with premature spastic contractions capable of luminal obliteration, previously termed "vigorous achalasia," with obstructive physiology extending throughout the distal esophagus 1

Important Caveat on Disease Progression

It remains unclear whether these subtypes represent sequential stages of disease progression or distinct phenotypic presentations of the same underlying disorder. 1 The British Society of Gastroenterology explicitly states this uncertainty, noting Type II is "presumed" to precede Type I, but definitive evidence is lacking.

Treatment Response by Subtype

Type II Achalasia (Best Prognosis)

• Responds best to all treatment modalities including botulinum toxin, pneumatic dilation, laparoscopic Heller myotomy (LHM), and per-oral endoscopic myotomy (POEM) 1
• Treatment options include pneumatic dilation, LHM, or POEM based on shared decision-making, local expertise, and patient preferences 1

Type I Achalasia (Intermediate Response)

• Shows similar response rates to Type II in most studies, though one retrospective analysis found no difference in outcomes between Type I and Type II after cardiomyotomy 1
• Treatment decisions should be based on local expertise, therapeutic availability, and patient choice rather than subtype alone 1
• Same treatment options as Type II: pneumatic dilation, LHM, or POEM 1

Type III Achalasia (Poorest Response)

• Consistently demonstrates the poorest response to standard LES-directed therapies across all treatment modalities 1
• POEM should be considered the preferred treatment for Type III achalasia because it allows unlimited proximal extension of the myotomy to address spastic esophageal body contractions 1
• Meta-analysis shows 92% response rate (95% CI: 84%-96%) with POEM in Type III achalasia, with myotomy length averaging 17.2 cm 1
• The extended myotomy addresses the obstructive physiology that extends beyond the LES into the distal esophageal body 1

Treatment Algorithm

For Types I and II:

1. Pneumatic dilation (PD), laparoscopic Heller myotomy (LHM), or POEM are all effective first-line options 1
2. Decision should incorporate patient characteristics (age, comorbidities, sigmoid esophagus, hiatus hernia), patient preferences, and local expertise 1
3. There is insufficient evidence to recommend specific therapies based on subtype distinction between Type I and Type II 1

For Type III:

1. POEM is the preferred treatment when expertise is available 1
2. Myotomy length should be tailored to the proximal extent of spastic contractions, guided by HRM findings, endoscopic ultrasound showing esophageal wall thickening, or intraoperative functional luminal imaging probe 1
3. Requires 20-40 procedures to achieve competence; should only be performed in high-volume centers 1

Critical Management Considerations

End-Stage Disease

• Patients with severe esophageal dilation and sigmoid deformation can be treated with POEM, though one report suggests doubling of adverse events in sigmoid esophagus 1
• Limited data comparing POEM to LHM as initial therapy in end-stage disease 1

Post-Treatment Reflux Risk

• All patients undergoing POEM should be counseled about high risk of reflux esophagitis requiring potential indefinite proton pump inhibitor therapy and/or surveillance endoscopy 1

Common Pitfall

The most critical error is treating Type III achalasia with standard LES-only directed therapy (short myotomy or pneumatic dilation), which consistently yields poor outcomes because it fails to address the spastic esophageal body component 1.