What is the appropriate diagnosis and management for an adult or elderly patient with a history of respiratory issues or significant environmental exposures, presenting with expanded lungs, apical thickening, and prominent vasculature?

Differential Diagnosis and Management of Expanded Lungs with Apical Thickening and Prominent Vasculature

The radiographic findings of expanded lungs with apical thickening and prominent vasculature most likely represent chronic obstructive pulmonary disease (COPD) with secondary pulmonary hypertension, though asbestos-related pleural disease and chronic thromboembolic pulmonary hypertension must be excluded based on exposure history and additional imaging.

Primary Diagnostic Considerations

COPD with Pulmonary Hypertension

• Expanded lungs (hyperinflation) combined with prominent vasculature strongly suggests COPD complicated by pulmonary hypertension, which develops in patients with chronic lung disease and significantly increases mortality risk 1
• The prominent vasculature indicates enlarged central pulmonary arteries (≥29 mm diameter) and increased pulmonary artery-to-ascending aorta ratio (≥1.0), which are CT findings that raise suspicion for pulmonary hypertension 2
• A segmental artery-to-bronchus ratio >1:1 in three or four lobes has high specificity for pulmonary hypertension 2
• Pulmonary hypertension in chronic lung disease results from vascular remodeling with medial hypertrophy, intimal fibrosis, and vascular ablation due to loss of small pulmonary vessels 2, 1, 3

Asbestos-Related Disease

• Apical thickening specifically raises concern for asbestos exposure, as apical pleural thickening is a recognized manifestation of asbestos-related pleural disease 2
• Asbestos causes pleural plaques and diffuse pleural thickening through collagen deposition in the subpleural space, which may subsequently calcify 2
• The combination of pleural thickening with parenchymal changes (expanded lungs) could represent coexisting asbestosis and chronic airway obstruction, as asbestos exposure is associated with obstructive physiologic abnormalities 2
• A detailed occupational history is essential: shipyard work, insulation work, construction, or other high-risk occupations from the 1950s-1980s 2

Chronic Thromboembolic Pulmonary Hypertension (CTEPH)

• CTEPH presents with prominent vasculature due to enlarged central pulmonary arteries and must be distinguished from other forms of pulmonary hypertension 2, 4
• Ventilation/perfusion (V/Q) scanning is the mandatory screening test to exclude CTEPH, showing multiple segmental perfusion defects if present 2, 4
• CT pulmonary angiography alone may miss CTEPH diagnosis, making V/Q scanning essential in the diagnostic algorithm 2, 4

Diagnostic Algorithm

Initial Imaging Assessment

• High-resolution CT with contrast is the first-line comprehensive imaging study to evaluate lung parenchyma, vasculature, and pleural abnormalities 2
• CT should assess for:
  • Emphysema or interstitial lung disease patterns 2
  • Pulmonary artery diameter and PA:aorta ratio 2
  • Pleural plaques, calcifications, or diffuse thickening 2
  • Mosaic perfusion pattern suggesting CTEPH 2

Functional Assessment

• Echocardiography is recommended for non-invasive assessment of pulmonary hypertension in patients with lung disease, evaluating right ventricular size, function, and estimated pulmonary artery pressures 2
• Pulmonary function tests will demonstrate obstructive pattern (reduced FEV1/FVC ratio) in COPD or restrictive pattern in asbestosis 2

Definitive Diagnosis

• Right heart catheterization is required only if therapeutic consequences are expected (e.g., lung transplantation evaluation, enrollment in clinical trials, or if alternative diagnoses like pulmonary arterial hypertension are suspected) 2
• Right heart catheterization is NOT routinely recommended for suspected pulmonary hypertension in lung disease unless specific treatment decisions depend on hemodynamic confirmation 2
• V/Q scanning must be performed before catheterization to exclude CTEPH, as this changes management entirely 2, 4

Management Approach

Optimize Underlying Lung Disease

• The optimal treatment of the underlying lung disease, including long-term oxygen therapy in patients with chronic hypoxemia, is the cornerstone of management for pulmonary hypertension due to lung diseases 2
• Oxygen therapy is reasonable for hypoxemic patients with oxygen saturations <92%, especially with associated respiratory disease 2

Pulmonary Hypertension-Specific Therapy

• Drugs approved for pulmonary arterial hypertension are NOT recommended in patients with pulmonary hypertension due to lung diseases, as most have shown no benefit or harmful effects 2, 1
• The exception is inhaled treprostinil, which improves exercise capacity in patients with interstitial lung disease and pulmonary hypertension 1
• Referral to a pulmonary hypertension expert center should be considered for patients with signs of severe pulmonary hypertension or severe right ventricular failure for individual-based treatment decisions 2

Asbestos-Related Disease Management

• If asbestos exposure is confirmed, no specific treatment exists for pleural thickening beyond symptomatic management 2
• Surveillance for mesothelioma is critical, as diffuse pleural thickening must be distinguished from progressive mesothelioma 2
• Decortication may be beneficial in severe cases of diffuse pleural thickening causing restrictive physiology 2

Critical Pitfalls to Avoid

• Do not assume prominent vasculature alone indicates pulmonary arterial hypertension requiring PAH-specific medications—this is Group 3 pulmonary hypertension (lung disease-associated), which does not respond to and may be harmed by PAH therapies 2, 1
• Do not skip V/Q scanning if pulmonary hypertension is confirmed—missing CTEPH means missing the only potentially curable form of pulmonary hypertension through pulmonary endarterectomy 2, 4
• Do not overlook occupational history—apical thickening without clear alternative explanation mandates detailed asbestos exposure assessment 2
• Do not perform right heart catheterization routinely in lung disease patients with suspected pulmonary hypertension unless it will change management 2