Achalasia Cardia Classification and Treatment

Classification System

The Chicago Classification system defines achalasia subtypes based on esophageal body pressurization patterns in patients with impaired lower esophageal sphincter (LES) relaxation and absent peristalsis 2, 3, 6
Type I Achalasia is characterized by minimal or negligible pressurization within the esophageal body, representing a decompensated, dilated esophagus that has progressed to end-stage disease 2, 3, 4, 6
Type II Achalasia is characterized by panesophageal pressurization with uniform simultaneous pressurization bands spanning from upper to lower sphincter, demonstrating the best treatment response across all therapeutic modalities 1, 2, 3, 5, 6
Type III Achalasia is characterized by premature (spastic) contractions, consistently demonstrating the poorest response to standard LES-directed therapies, requiring specialized management with extended myotomy (POEM preferred) 2, 3, 4, 5, 6

The American Gastroenterological Association recommends treatment decisions based on Chicago Classification subtype, with Type II responding best to all therapies, Type I showing intermediate response, and Type III requiring POEM with extended myotomy when expertise is available 5, 6
Treatment success rates vary by subtype: Type II achalasia has success rates of 71% with botulinum toxin, 90-91% with pneumatic dilation, and 100% with Heller myotomy, while Type III achalasia has success rates of only 29-33% across all treatment modalities 5, 6
The European Society of Gastrointestinal Endoscopy suggests that POEM in EGJ outflow obstruction has long-term success rates of 80-85%, somewhat lower compared to classic achalasia subtypes 7

The Chicago Classification recognizes EGJ outflow obstruction as a fourth entity that can mimic achalasia, requiring intensive clinical evaluation (endoscopic ultrasound, computed tomography, timed barium esophagram) to clarify etiology before considering permanent interventions 1, 2, 3, 7
The American College of Gastroenterology recommends careful diagnosis and classification of achalasia subtypes to guide treatment decisions and improve patient outcomes 4, 5, 6