Overview
Definition:
Thoracoscopic esophageal myotomy is a minimally invasive surgical procedure performed to treat achalasia by cutting the thickened muscle layers of the lower esophageal sphincter (LES) and distal esophagus
It aims to relieve dysphagia and regurgitation by reducing the obstruction caused by the LES
This technique utilizes laparoscopic instruments inserted through small incisions in the chest.
Epidemiology:
Achalasia is a rare esophageal motility disorder with an estimated incidence of 1 in 100,000 people
It affects men and women equally, typically presenting in the third to fifth decades of life
There is no clear geographical predisposition, but genetic factors may play a role
Long-standing achalasia has a small but increased risk of esophageal carcinoma.
Clinical Significance:
Achalasia significantly impacts quality of life due to progressive dysphagia, regurgitation, chest pain, and weight loss
Effective management, including thoracoscopic myotomy, can restore normal swallowing function, prevent malnutrition, reduce complications like aspiration pneumonia, and improve overall patient well-being
It is a cornerstone treatment for moderate to severe achalasia and is preferred over dilation or medical management for long-term symptom control.
Clinical Presentation
Symptoms:
Hallmark symptom is progressive dysphagia, initially for solids, then for liquids
Postprandial regurgitation of undigested food
Substernal chest pain, often mistaken for cardiac pain
Heartburn, which may be atypical due to impaired esophageal clearance
Unintentional weight loss
Nocturnal cough and recurrent aspiration, leading to pneumonia
Halitosis
Feeling of food stuck in the throat.
Signs:
Generally, physical examination may be unremarkable in early stages
Cachexia may be present in advanced cases with significant weight loss
Auscultation may reveal absent or diminished bowel sounds if there is a large esophageal bolus
Palpation may reveal epigastric tenderness
Vital signs are usually stable unless complications like aspiration pneumonia are present.
Diagnostic Criteria:
Diagnosis is primarily based on a combination of clinical symptoms and objective investigations
Chicago classification of esophageal motility disorders is used to classify achalasia subtypes based on high-resolution manometry (HRM)
Key diagnostic features include impaired LES relaxation, absence of peristalsis in the esophageal body, and elevated LES pressure
Extended esophageal dilation and a "bird beak" or "sigmoid" appearance on barium swallow are suggestive.
Diagnostic Approach
History Taking:
Detailed history of dysphagia progression (solids vs
liquids, duration, severity)
Characterization of chest pain (location, duration, triggers, relief)
Nature and frequency of regurgitation
Associated symptoms like weight loss, cough, heartburn, or voice changes
Previous investigations or treatments for dysphagia
Family history of gastrointestinal disorders
Red flags include rapid onset of dysphagia, significant weight loss, bleeding, and a history suggestive of malignancy.
Physical Examination:
General assessment for nutritional status and signs of dehydration
Careful examination of the abdomen for any masses or tenderness
Respiratory examination to detect signs of aspiration pneumonia (rales, decreased breath sounds)
Examination of the oropharynx for any abnormalities
Cardiovascular examination to rule out cardiac causes of chest pain.
Investigations:
Barium swallow: reveals dilated esophagus, tapering at the LES ("bird beak" or "sigmoid" appearance), delayed emptying
Esophageal manometry: Gold standard for diagnosis, demonstrating elevated LES pressure, incomplete LES relaxation, and absent esophageal peristalsis
High-resolution manometry (HRM) with 3-D pressure topography allows classification of achalasia subtypes
Esophagogastroduodenoscopy (EGD): to rule out other causes of dysphagia, such as strictures, malignancy, eosinophilic esophagitis
may reveal retained food material and a tight LES
Esophageal manometry confirms the diagnosis and guides surgical approach
CT scan of chest and abdomen: to rule out extrinsic compression and assess for malignancy, especially in older patients or those with rapid weight loss.
Differential Diagnosis:
Peptic stricture: typically history of GERD, solid dysphagia predominantly, normal peristalsis
Esophageal malignancy: rapid onset dysphagia, significant weight loss, associated anemia, may have palpable mass
Diffuse esophageal spasm: intermittent chest pain, intermittent dysphagia, normal LES relaxation and peristalsis on manometry
Scleroderma: history of Raynaud's phenomenon, skin changes, absent peristalsis, but LES relaxation is usually preserved
Eosinophilic esophagitis: usually associated with allergies, dysphagia for solids, may show eosinophilic infiltration on biopsy
Pseudoachalasia: secondary to malignancy at the GE junction, typically older age group, rapid onset, weight loss, abnormal LES relaxation due to tumor infiltration.
Management
Initial Management:
Dietary modifications: soft, pureed foods, avoiding trigger foods
Avoiding eating close to bedtime
Head elevation during sleep
Hydration with liquids
Weight maintenance monitoring
Nutritional support if significant weight loss is present.
Medical Management:
Pharmacological treatment is generally for palliative relief or as a bridge to more definitive treatment
Calcium channel blockers (e.g., Nifedipine 10-20 mg sublingually or orally 30 mins before meals): reduce LES pressure but often provide suboptimal and temporary relief
Nitrates (e.g., Isosorbide dinitrate 5-10 mg sublingually): similar mechanism and limitations to calcium channel blockers
Botulinum toxin injection into the LES: effective for temporary relief (6-12 months) but has limitations in patients who may later require surgery due to potential fibrosis, especially for older or high-risk patients.
Surgical Management:
Surgical indications: Moderate to severe achalasia with significant dysphagia, regurgitation, and weight loss not adequately controlled by medical therapy or dilation
Patients with achalasia subtypes I and II on HRM often have excellent results with myotomy
Thoracoscopic esophageal myotomy (Heller myotomy with fundoplication): The preferred approach for most patients
It involves a myotomy of the LES and distal esophagus, typically performed laparoscopically or thoracoscopically
A partial fundoplication (e.g., Dor or Toupet) is usually added to reduce post-myotomy gastroesophageal reflux
Percutaneous endoscopic myotomy (POEM): An alternative endoscopic approach that achieves a myotomy without external incisions, particularly useful in patients with prior abdominal surgery or complex anatomy.
Supportive Care:
Nutritional support: Ensuring adequate caloric and fluid intake
Management of aspiration: Prophylactic antibiotics for aspiration pneumonia, incentive spirometry
Pain management: Adequate analgesia post-operatively
Monitoring for complications: Careful observation for bleeding, perforation, infection, and reflux
Psychological support: Addressing the impact of chronic illness on mental health.
Complications
Early Complications:
Bleeding: Intraoperative or postoperative hemorrhage
Esophageal perforation: Rare but serious complication, may require immediate repair
Pneumothorax: Due to pleural entry during thoracoscopic approach
Mediastinitis: Infection of the mediastinum, a life-threatening complication if perforation occurs
Injury to adjacent organs: Spleen, diaphragm, or vagus nerve injury
Aspiration pneumonia: Postoperative aspiration of retained secretions
Gastric distension: Due to air insufflation during surgery.
Late Complications:
Gastroesophageal reflux disease (GERD): Common after myotomy, especially without adequate fundoplication
Esophagitis: Inflammation of the esophagus due to reflux
Recurrent dysphagia: Due to incomplete myotomy, scarring, or development of new motility disorders
Weight gain: Paradoxically, some patients may gain weight after successful myotomy due to improved eating
Esophageal cancer: Small increased risk of squamous cell carcinoma with long-standing achalasia, surveillance is recommended.
Prevention Strategies:
Meticulous surgical technique by experienced surgeons
Intraoperative intraesophageal methylene blue injection to confirm watertight closure of mucosa if a full-thickness myotomy is performed
Careful dissection to avoid injury to surrounding structures
Appropriate selection of patients for fundoplication
Postoperative education on diet and lifestyle modifications to minimize reflux
Regular follow-up to monitor for symptoms of reflux or recurrence.
Prognosis
Factors Affecting Prognosis:
Disease duration: Longer duration of symptoms may lead to more irreversible esophageal changes
Type of achalasia on manometry: Type III achalasia (spastic) may have a less favorable outcome with myotomy alone
Surgeon's experience: Thoracoscopic myotomy is a technically demanding procedure
Extent of myotomy: Adequate length of myotomy is crucial for symptom relief
Presence and type of fundoplication.
Outcomes:
Thoracoscopic esophageal myotomy offers excellent long-term relief of dysphagia and regurgitation in 70-90% of patients
Significant improvement in quality of life is expected
Resolution of chest pain is variable
However, a small percentage of patients may experience persistent or recurrent symptoms
POEM has shown comparable short-term outcomes to surgical myotomy.
Follow Up:
Regular follow-up appointments are essential, typically every 6-12 months for the first 2-3 years, then annually
Monitoring for symptom recurrence (dysphagia, regurgitation, chest pain), signs of GERD, and weight changes
Endoscopic surveillance is recommended every 2-5 years, especially in patients with long-standing achalasia, to screen for esophageal dysplasia or malignancy.
Key Points
Exam Focus:
Thoracoscopic Heller myotomy is the gold standard surgical treatment for achalasia
Differentiate achalasia from pseudoachalasia and other motility disorders
Recognize the role of high-resolution manometry (HRM) in diagnosis and classification
Understand the indications and contraindications for myotomy and POEM
Complications include perforation, bleeding, and GERD
Long-term follow-up is crucial for early detection of recurrence and cancer.
Clinical Pearls:
Always consider achalasia in patients with progressive dysphagia to both solids and liquids, especially with regurgitation and chest pain
Barium swallow and HRM are key diagnostic tools
A well-executed myotomy should extend sufficiently into the distal esophagus and gastric cardia
The addition of a partial fundoplication is important for symptom control and to mitigate reflux post-myotomy
POEM is an excellent alternative for patients with contraindications to abdominal surgery or significant adhesions.
Common Mistakes:
Misdiagnosing achalasia as GERD or functional dyspepsia
Inadequate length of the myotomy, leading to recurrent symptoms
Performing a full fundoplication after myotomy, which can cause severe dysphagia
Failing to investigate for malignancy in older patients with rapid onset dysphagia
Neglecting long-term follow-up, missing early signs of recurrence or cancer.