Thoracic ultrasonography in the follow-up of pulmonary infarct

Pulmonary infarction is an ischaemic necrosis resulting from pulmonary arterial occlusion, occurring in approximately one-third of pulmonary thromboembolism cases. While computed tomography angiography remains the gold standard for diagnosis, its use in follow-up is limited by radiation exposure. Thoracic ultrasonography, a bedside, radiation-free and repeatable modality, may serve as an alternative tool for monitoring pulmonary infarction.

We present a 44-year-old woman who developed sudden dyspnoea and back pain 1 week after venous surgery. Computed tomography angiography confirmed pulmonary thromboembolism, and persistent flank pain was attributed to pulmonary infarction. Thoracic ultrasonography revealed a hypoechoic, pleural-based consolidation in the left hemithorax measuring 19 × 11 mm. The patient was treated with anticoagulation and followed weekly with thoracic ultrasonography. Her symptoms improved, and by the sixth week, the consolidation had completely resolved.

Pulmonary infarction has traditionally been associated with poor outcomes in older patients with comorbidities; however, it may also occur in young, otherwise healthy individuals. The clinical significance of pulmonary infarction remains uncertain, although some studies suggest potential associations with delayed recovery and functional impairment. Thoracic ultrasonography demonstrates good sensitivity and specificity in detecting pulmonary infarction and offers several advantages over computed tomography angiography for follow-up, including safety, accessibility and repeatability. Evidence suggests that infarct resolution typically occurs within 6 to 12 weeks, a period during which thoracic ultrasonography may be effectively utilised to monitor lesion regression.

This case highlights the role of thoracic ultrasonography in the follow-up of pulmonary infarction. Although limited to peripheral, pleura-based lesions, thoracic ultrasonography represents a safe, practical and repeatable imaging modality for monitoring pulmonary infarction resolution and may reduce the need for repeated computed tomography angiography in clinical practice.