In a 45-year-old man with prior rib surgery and intermittent chest pain, should we inform his primary care physician about the incidental significant left pleural effusion seen on the nuclear stress test, or can we manage it within our service?

Management of Incidental Pleural Effusion Found on Nuclear Stress Test

You should immediately inform the patient's primary care physician about this significant left pleural effusion and coordinate care, as this incidental finding requires systematic diagnostic workup that extends beyond cardiology's scope and may indicate serious underlying pathology requiring urgent evaluation. 1

Why PCP Notification is Essential

Pleural effusions have over 60 recognized causes including malignancy, infection, pulmonary embolism, and systemic diseases—many of which fall outside cardiology's primary domain and require comprehensive evaluation. 1 The differential diagnosis is wide enough that a systematic, multidisciplinary approach is necessary to avoid missing life-threatening conditions. 1

Key Clinical Context

• This patient has concerning features: 45-year-old with prior rib surgery (potential for post-traumatic complications, empyema, or malignancy), intermittent chest pain, and now a "significant" effusion. 1
• The chest pain may be pleuritic rather than cardiac, which occurs in approximately 75% of patients with pulmonary embolism and pleural effusion—a diagnosis that could be missed if focused solely on cardiac evaluation. 1
• Drug-induced effusions are increasingly common (especially with tyrosine kinase inhibitors), requiring detailed medication history review. 1

Immediate Next Steps

Thoracic ultrasound should be performed immediately to assess effusion size, character, and safety for diagnostic thoracentesis, and to look for pleural nodularity suggesting malignancy. 1, 2

Diagnostic thoracentesis is indicated for all new, unexplained pleural effusions using a 21G needle, sending fluid for: 1

• Protein and LDH (to distinguish transudate vs. exudate)
• pH, cell count with differential
• Gram stain, culture (in blood culture bottles to increase yield), and AFB stain
• Cytology

Critical Pitfall to Avoid

Do not assume this is a simple transudate without sampling the fluid. While bilateral effusions in the setting of heart failure may not require aspiration, a unilateral effusion—especially in a patient with prior thoracic surgery and chest pain—demands investigation. 1 Only 60% of malignant effusions are diagnosed on initial cytology, and empyema can develop rapidly if infection is present. 1

Why Cardiology Alone Cannot Manage This

The British Thoracic Society guidelines explicitly recommend referral to a chest physician when pleural fluid analysis and clinical features do not provide a clear diagnosis. 1 The workup may require:

• Contrast-enhanced CT thorax (best performed with fluid present to visualize pleura)
• Pleural biopsy (ultrasound/CT-guided, closed, or thoracoscopic)
• Specialized testing based on initial fluid analysis
• Treatment ranging from antibiotics for empyema to pleurodesis for malignancy

1

Coordination of Care

Notify the PCP immediately with specific findings: 1

• Document the size and laterality of the effusion
• Provide copies of the nuclear stress test images
• Communicate the need for urgent thoracentesis (within 24-48 hours)
• Ensure follow-up is arranged within 72 hours regardless of initial findings

The PCP should coordinate: 1

• Urgent pulmonology referral if fluid analysis is non-diagnostic
• Evaluation for systemic causes (heart failure, cirrhosis, renal disease)
• Review of occupational history including asbestos exposure
• Complete medication review for drug-induced effusion

This collaborative approach ensures nothing is missed while the cardiac evaluation continues, optimizing both diagnostic accuracy and patient safety. 1, 3