What is a sigmoid esophagus?

Sigmoid Esophagus: Definition and Management

Sigmoid esophagus is an advanced stage of achalasia characterized by significant esophageal dilation, tortuosity, and rotation, where the esophagus takes on an S-shaped or sigmoid appearance due to long-standing obstruction at the lower esophageal sphincter. 1

Anatomical Characteristics

• Significantly dilated esophageal lumen
• Tortuous, swerved, and rotated esophagus forming an S-shape
• Classified into subtypes:
  • S1: moderate sigmoid-shaped dilation
  • S2: severe sigmoid-shaped dilation with greater tortuosity 1

Pathophysiology

Sigmoid esophagus represents the end-stage manifestation of achalasia, developing after prolonged:

• Impaired lower esophageal sphincter (LES) relaxation
• Absent esophageal peristalsis
• Progressive esophageal dilation due to food and fluid retention
• Esophageal elongation and tortuosity over time 2

Clinical Presentation

Patients with sigmoid esophagus typically present with:

• Severe, long-standing dysphagia
• Regurgitation of undigested food
• Weight loss and malnutrition
• Respiratory symptoms (aspiration, pneumonia)
• Chest pain
• Food retention in the dilated esophagus 3

Diagnosis

Diagnosis relies on:

1. Barium Esophagram:

   • Shows dilated, tortuous, S-shaped esophagus
   • Classic "bird's beak" appearance at the gastroesophageal junction

2. Esophagogastroduodenoscopy (EGD):

   • Reveals dilated, tortuous esophagus
   • Often contains retained food and secretions
   • Difficulty advancing the scope through the lower esophageal sphincter 3

3. High-Resolution Manometry:

   • Confirms achalasia subtype
   • Shows elevated LES pressure
   • Absent peristalsis 2

Treatment Options

Treatment of sigmoid esophagus is challenging and should be tailored based on:

• Severity of symptoms
• Degree of esophageal dilation and tortuosity
• Patient's overall health status
• Previous interventions

1. Endoscopic Approaches

• Peroral Endoscopic Myotomy (POEM):

  • Long-term success rate of 96.8% in sigmoid esophagus
  • Allows for longer myotomy extending into the distal esophagus
  • Particularly beneficial for type III achalasia with sigmoid deformation
  • Morphological changes may make tunneling more challenging but don't prevent successful outcomes 1

• Endoscopic Balloon Dilation:

  • May be difficult or impossible due to tortuosity
  • Specialized endoscopic dilators have been developed for tortuous esophagus
  • Generally less effective as a standalone treatment for sigmoid esophagus 4

2. Surgical Approaches

• Laparoscopic Heller Myotomy with Dor Fundoplication:

  • First-line surgical approach for many cases
  • Can provide satisfactory symptom improvement
  • Less invasive than esophagectomy 2, 3

• Esophagectomy:

  • Reserved for severe cases or failed previous interventions
  • Laparoscopic transhiatal approach is feasible with specialized expertise
  • Considered when the esophagus is severely dilated and dysfunctional
  • Higher morbidity but definitive treatment 5

Treatment Algorithm

1. Initial Assessment:

   • Determine achalasia subtype (I, II, or III)
   • Assess degree of sigmoid deformation (S1 or S2)
   • Evaluate patient's surgical risk

2. First-line Treatment:

   • For most patients: POEM or laparoscopic Heller myotomy with Dor fundoplication
   • POEM is preferred for type III achalasia with sigmoid esophagus 1

3. For Treatment Failures or Severe Cases:

   • Consider esophagectomy when:
     • Previous myotomy has failed
     • Extreme dilation prevents effective myotomy
     • Severe malnutrition and inability to maintain nutrition
     • End-stage disease with complete esophageal dysfunction 5

Prognosis and Outcomes

• POEM has shown excellent 2-year outcomes with symptom relief in over 96% of cases 1
• Laparoscopic Heller myotomy with Dor fundoplication can provide satisfactory results in selected patients 3
• Approximately 10% of post-myotomy patients will have symptom recurrence, and 5% may require reoperation 5
• Clinical reflux complications occur in about 25.8% of patients after POEM for sigmoid-type achalasia 1

Pitfalls and Caveats

• Sigmoid esophagus makes endoscopic and surgical procedures technically challenging
• Adhesions and fibrosis at the hiatal area increase surgical difficulty
• Accurate preoperative assessment of esophageal shape and location is critical
• These procedures should be performed at specialized centers with expertise in managing complex esophageal disorders 5
• Long-term follow-up is essential to monitor for symptom recurrence and reflux complications