II. Epidemiology
- Rare condition with Incidence <5% of cases presenting to specialty centers
- More common in older adults than younger patients
III. Pathophysiology
- Chronic progressive degenerative disorder often with delayed diagnosis
- Delayed diagnosis results in esophageal dilitation, resulting in cases refractory to surgical management
- Chronic esophageal Smooth Muscle denervation
- Deficient distal esophagus Cholinergic innervation due to loss of myenteric plexus (Auerbach's plexus)
- Decreased tissue nitric oxide
- Inhibitory Neuron loss
- Results
- Loss of normal esophageal peristalsis
- Lower Esophageal Sphincter (LES) dysfunction, preventing LES relaxation
- LES Incoordinate contraction
- LES tonic contractions
- Constriction of LES in response to Swallowing
IV. Types
- Achalasia Type 1 (Classic Achalasia)
- No contractility or peristalsis
- Lower esophageal sphincter fails to relax (all Achalasia types)
- Responds to Laparoscopic Heller Myotomy
- Achalasia Type 2 (with esophageal compression)
- No normal peristalsis (but some pressurizations)
- Lower esophageal sphincter fails to relax (all Achalasia types)
- Responds to all treatment options
- Achalasia Type 3 (Spastic Achalasia)
- No normal peristalsis
- Spastic contractions in distal Esophagus (>20% of swallows)
- Lower esophageal sphincter fails to relax (all Achalasia types)
- Responds poorly to treatment
V. Symptoms
- Dysphagia
- Chest Pain
- Regurgitation of food, Saliva, esophageal secretions
- Weight loss
VI. Diagnostics
- Upper Endoscopy Achalasia findings
- Food retained in Esophagus
- Increased resistance across esophagogastric junction
- High-Resolution Esophageal Manometry
- Required for Achalasia diagnosis
- Performed with Nasogastric Tube with closely positioned pressure sensors measure intraluminal pressure
- Esophageal pressures are measured as the patient swallows various foods and liquids
- Lower esophageal sphincter pressure is also measured before Swallowing and during relaxation
- Upper GI (Barium Esophagram)
- Proximal esophageal dilatation
- Beadlike or "bird beak" narrowing of distal segment at LES
- Spasm of lower esophageal sphincter
VII. Differential Diagnosis
VIII. Management
- See Esophageal Dysmotility for general measures
- Myotomy (definitive therapy)
- Pneumatic dilation (by endoscopy)
- Disrupts lower esophageal sphincter
- Not as effective or longlasting as myotomy (dilation may need to be repeated)
- Onabotulinumtoxin A
- Endoscopic injection into lower esophageal sphincter
- Unknown efficacy, but may be used in patients at too high risk for surgery