In situ pulmonary arterial thrombosis is a distinct entity from pulmonary embolism, arising de novo due to endothelial dysfunction and inflammation in conditions such as COVID-19 and trauma.
In situ pulmonary arterial thrombosis is increasingly recognized as a distinct pathophysiological entity from embolic pulmonary embolism, with important implications for clinical management.
Filling defects identified in the pulmonary arterial tree are commonly presumed to represent an embolic phenomenon originating from thrombi formed in remote veins, particularly lower-extremity deep venous thrombosis (DVT). However, accumulating evidence supports an underappreciated cause for pulmonary arterial thrombosis (PAT), namely, de novo thrombogenesis-whereby thrombosis arises within the pulmonary arteries in the absence of DVT. Although historically underrecognized, in situ PAT has become of heightened importance with the emergence of SARS-CoV-2 infection. In situ PAT is attributed to endothelial dysfunction, systemic inflammation, and acute lung injury and has been described in a range of conditions including COVID-19, trauma, acute chest syndrome in sickle cell disease, pulmonary infections, and severe pulmonary arterial hypertension. The distinction between pulmonary embolism and in situ PAT may have important implications regarding management decisions and clinical outcomes. In this review, we summarize the pathophysiology, imaging appearances, and management of in situ PAT in various clinical situations. This understanding will promote optimal tailored treatment strategies for this increasingly recognized entity.
Baranga et al. (Wed,) conducted a review in In situ pulmonary arterial thrombosis. In situ pulmonary arterial thrombosis is a distinct entity from pulmonary embolism, arising de novo due to endothelial dysfunction and inflammation in conditions such as COVID-19 and trauma.