What causes gastrointestinal symptoms in patients with double aortic arch?

Gastrointestinal Symptoms in Double Aortic Arch

Gastrointestinal symptoms in double aortic arch occur due to direct mechanical compression of the esophagus by the vascular ring that encircles both the trachea and esophagus. 1 This anatomical compression leads to symptoms such as dysphagia, choking with feeds, and vomiting.

Pathophysiology of Gastrointestinal Symptoms

Double aortic arch (DAA) is a congenital vascular anomaly where both the right and left aortic arches persist, forming a complete vascular ring that encircles and compresses both the trachea and esophagus. This condition:

• Represents about 50-60% of all vascular rings 1
• Can be right-dominant (most common, ~72%), left-dominant, or co-dominant 2
• Creates direct mechanical compression on the esophagus, leading to:
  • Dysphagia (difficulty swallowing)
  • Choking episodes, especially during feeding
  • Vomiting
  • Feeding problems and failure to thrive in infants 3

Clinical Presentation

The gastrointestinal manifestations typically present as:

• Choking during feeding (most common GI symptom) 2
• Dysphagia, which can be severe in adults with undiagnosed DAA 4
• Feeding difficulties in infants 3
• Failure to thrive due to inadequate nutrition 3

It's important to note that while 40% of patients present with gastrointestinal symptoms, respiratory symptoms are more common (91%), including stridor (77%) 2. The combination of both respiratory and gastrointestinal symptoms should raise suspicion for a vascular ring.

Diagnostic Approach

When gastrointestinal symptoms suggest possible DAA:

1. Barium esophagram: Shows characteristic posterior indentation of the esophagus 3, 5
2. Cardiac Magnetic Resonance (CMR): Provides comprehensive assessment of the vascular ring and its relationship to the trachea and esophagus 1
3. CT angiography: Alternative to CMR, especially useful in adults 3
4. Bronchoscopy: May reveal pulsatile compression of the trachea 1

CMR is particularly valuable as it provides detailed imaging of both the vascular structures and the airway, allowing for conclusive diagnosis and therapeutic planning 1.

Management

For patients with symptomatic double aortic arch causing gastrointestinal symptoms:

• Surgical division of the non-dominant arch is the definitive treatment 4, 2, 3
• Surgery is typically performed through a left thoracotomy approach 5
• The procedure involves:
  • Identifying the smaller/non-dominant arch
  • Ligating and dividing the compressive segment
  • Division of the ligamentum arteriosum 4

Outcomes and Prognosis

Following surgical repair:

• Mortality is very low (approximately 4% at 5 years) 2
• Complete symptomatic improvement occurs in most patients (76%) 5
• Partial improvement occurs in some (21%) 5
• Gastrointestinal symptoms typically resolve more completely than respiratory symptoms 2
• Persistent gastrointestinal symptoms are rare (6%) compared to respiratory symptoms (54%) 2

Important Considerations and Pitfalls

• Delayed diagnosis: Despite typical symptoms from early childhood, diagnosis may be missed until adulthood 3
• Complications of prolonged intubation: In infants requiring ventilatory support, prolonged endotracheal and nasogastric intubation can lead to iatrogenic esophageal-aortic erosion 6
• Associated anomalies: Cardiac anomalies may be present in 18% of cases 2
• Persistent tracheomalacia: May require additional interventions even after vascular ring division 2

Early diagnosis and surgical intervention are crucial to prevent long-term complications and improve outcomes in patients with double aortic arch presenting with gastrointestinal symptoms.