Pulmonary Artery Filling Defects: Beyond Pulmonary Embolism

Pulmonary embolism is the most frequent cause of pulmonary artery filling defects seen on computed tomography pulmonary angiography, but clinicians should be aware that spurious filling defects may occur. Here, Kermellly et al presents a CT pulmonary angiography of a 60-year-old man with severe emphysema in whom endoscopic lung volume reduction coil treatment was performed in 2013. In Jan 2018, a chest CT angiography was performed to exclude pulmonary embolism. Bilateral filling defects of the central pulmonary arteries were seen, leading to a clinical suspicion of pulmonary embolism. However, repeating the chest CT angiography with subsequent vascular phase led to the disappearance of the pulmonary artery defects, compatible with systemic-pulmonary shunting. They suspect that this situation originated from bronchial artery neovascularization after coil-induced inflammation and scarring processes.