Pulmonary Vascular Manifestations of COVID-19 Pneumonia

Lang, Min; Som, Avik; Carey, Denston; Reid, Nicholas; Mendoza, Dexter P.; Flores, Efren J.; Li, Matthew D.; Shepard, Jo-Anne O.; Little, Brent P.

BACKGROUND: Parenchymal findings in COVID-19 pneumonia on computed tomography (CT) have been well characterized. However, the role of pulmonary vascular pathology in COVID-19 pneumonia is still not well understood. PURPOSE: To investigate pulmonary vascular abnormalities on CT pulmonary angiography in patients with COVID-19 pneumonia. MATERIALS AND METHODS: In this retrospective study, 48 patients with RT-PCR confirmed COVID-19 infection who had undergone CT pulmonary angiography between 3/22/20 and 4/5/20 in our large urban health care system were included. Patient demographics and clinical data were collected through the electronic medical record system. Twenty-five patients underwent dual energy CT (DECT) as part of the standard CT pulmonary angiogram protocol at a subset of the hospitals. Two thoracic radiologists independently assessed all studies. Disagreement in assessment was resolved by consensus discussion with a third thoracic radiologist. RESULTS: Of the 48 patients, 45 patients required admission, with 18 admitted to the ICU, and 13 requiring intubation. Seven patients (15%) were found to have pulmonary emboli. Dilated vessels were seen in 41 cases (85%), with 38 (78%) and 27 (55%) of cases demonstrating vessel enlargement within and outside of lung opacities, respectively. Dilated distal vessels extending to the pleura and fissures were seen in 40 cases (82%) and 30 cases (61%), respectively. On DECT, mosaic perfusion pattern was observed in 24 cases (96%), regional hyperemia overlapping with areas of pulmonary opacities or immediately surrounding the opacities were seen in 13 cases (52%), opacities associated with corresponding oligemia were seen in 24 cases (96%), and hyperemic halo was seen in 9 cases (36%). CONCLUSION: Pulmonary vascular abnormalities such as vessel enlargement and regional mosaic perfusion patterns are common in COVID-19 pneumonia. Perfusion abnormalities are also frequently observed at DECT in COVID-19 pneumonia and may suggest an underlying vascular process.