Can a thoracic aneurysm cause a chronic cough?

Thoracic Aortic Aneurysm as a Cause of Chronic Cough

Yes, a thoracic aortic aneurysm can cause chronic cough through compression of adjacent structures in the thorax, particularly the trachea and bronchi. 1, 2, 3

Mechanism of Cough in Thoracic Aortic Aneurysm

Thoracic aortic aneurysms can cause cough through several mechanisms:

1. Direct compression of airways: Enlarging aneurysms can directly compress the trachea or main bronchi, triggering the cough reflex 1
2. Compression of the recurrent laryngeal nerve: Particularly with aortic arch aneurysms, leading to vocal cord dysfunction and cough 4
3. Compression of the esophagus: Leading to irritation and stimulation of the esophageal-bronchial cough reflex 1

Clinical Presentation and Warning Signs

When a thoracic aortic aneurysm causes cough, certain features may help identify this uncommon but serious etiology:

• Chronic cough that is persistent and refractory to standard treatments 2, 3
• Associated symptoms that may include:
  • Hoarseness of voice (due to recurrent laryngeal nerve compression) 2, 4
  • Dysphagia (difficulty swallowing) 4
  • Chest, back, or interscapular pain 1
  • Stridor from tracheal compression 1
  • Dyspnea from lung compression 1

Risk Factors to Consider

Patients with the following risk factors should prompt higher suspicion for thoracic aortic aneurysm when presenting with chronic cough:

• History of bicuspid aortic valve 1, 2
• Hypertension 1
• Smoking history 1, 3
• Chronic obstructive pulmonary disease 1
• Previous cardiac surgery, especially aortic valve replacement 2
• Genetic syndromes predisposing to thoracic aortic disease 1
• History of trauma to the chest 5

Diagnostic Approach

For patients with unexplained chronic cough (lasting >8 weeks) 1, especially with risk factors for aortic disease:

1. Chest radiography: May show widened mediastinum or abnormal aortic contour 2
2. CT aortogram/CT angiography: Gold standard for diagnosis, providing detailed information about aneurysm size, location, and relationship to adjacent structures 2, 3
3. Laryngoscopy: May reveal vocal cord dysfunction or paralysis if the recurrent laryngeal nerve is compressed 4

Management Implications

The identification of a thoracic aortic aneurysm as the cause of chronic cough has significant management implications:

• Surgical intervention is typically indicated when symptoms such as cough develop, as this indicates compression of adjacent structures 1, 2, 5
• Resolution of cough typically occurs following successful surgical repair of the aneurysm 2
• Untreated symptomatic thoracic aortic aneurysms carry significant risk of rupture and death 3

Common Pitfalls to Avoid

1. Misattribution to common causes: Chronic cough is frequently attributed to asthma, GERD, or upper airway cough syndrome without consideration of rarer but more serious causes 1, 2
2. Empiric treatment failure: Persistence of cough despite trials of inhaled steroids, proton pump inhibitors, or antihistamines should prompt further investigation 2
3. Overlooking cardiovascular causes: In patients with risk factors for aortic disease, thoracic imaging should be considered even when pulmonary causes seem more likely 3, 6

Early recognition and appropriate management of thoracic aortic aneurysm causing chronic cough is essential to prevent potentially catastrophic outcomes such as rupture or dissection.