Pulmonary Vascular Manifestations of COVID-19 Pneumonia

Abstract

Purpose: To investigate pulmonary vascular abnormalities at CT pulmonary angiography (CT-PE) in patients with coronavirus disease 2019 (COVID-19) pneumonia.

Materials and methods: In this retrospective study, 48 patients with reverse-transcription polymerase chain reaction-confirmed COVID-19 infection who had undergone CT-PE between March 23 and April 6, 2020, in a 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-PE 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 intensive care unit, 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%) 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. At 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.Supplemental material is available for this article.© RSNA, 2020.

Figure 1:

Images in a 69-year-old man hospitalized for fever, weakness, and chills, found to have coronavirus disease 2019. CT pulmonary angiogram was obtained on day 4 of admission for acute intermittent tachycardia, desaturation, and new complaint of shortness of breath. The study was negative for pulmonary emboli. A, Contrast-enhanced CT pulmonary angiogram of the upper lungs at lung windows shows a region of peripheral ground-glass opacity and consolidation in the right upper lobe (arrowheads); the subsegmental vessels within the opacities are dilated, and the right upper lobe vessels proximal to the opacity are also dilated (arrows). B, Pulmonary blood volume (PBV) image at the same level shows a large peripheral perfusion defect corresponding to the distribution of right upper lobe opacity, with a surrounding halo of increased perfusion (arrows). There is also heterogeneous perfusion of the left upper lobe. C, CT image of the lower lungs in the same patient shows peripheral ground-glass opacities and consolidation in the lower lobes, middle lobe, and lingula with a somewhat round or wedge-shaped appearance (arrowheads). D, PBV image shows perfusion defects corresponding to the areas of opacity in C, with surrounding halos of increased perfusion (arrows).

Figure 2:

Images in a 45-year-old man who presented with cough and fever, requiring supplemental oxygen via nasal cannula, and was found to have coronavirus disease 2019. On day 5 of admission, patient underwent CT pulmonary angiography for acute shortness of breath, tachypnea, and an elevated d-dimer level. A, Contrast-enhanced CT pulmonary angiogram of the upper lungs shows multiple ground-glass opacities and consolidation with a peripheral predominance; several perilobular bands of consolidation suggest an organizing lung injury pattern (arrowheads). Subsegmental vessels supplying regions of opacity are dilated (arrows). B, Corresponding iodine map image shows increased perfusion of some areas of opacity (arrows). C, Axial CT image as part of the same examination shows additional peripheral ground-glass opacities and consolidation in the lower lungs, with enlarged vessels within and supplying regions of lung with opacity (arrows), while vessels in the anterior lungs are smaller in caliber with relatively lower regional attenuation of the anterior lungs. D, Corresponding iodine map image shows increased perfusion to the posterior lower lobes in general, decreased perfusion of the anterior lungs (long arrows), and small perfusion defects corresponding to posterior areas of opacity seen in C (short arrows).

Figure 3:

A, B, Images in a 41-year-old man who presented to the emergency department with acute shortness of breath and underwent CT pulmonary angiography for concern for pulmonary embolism. Patient tested positive for coronavirus disease 2019 infection. A, Peripheral ground-glass opacities are present in the posterior upper lobes (arrowheads); regional dilatation of vessels is noted in adjacent upper lobes. B, Pulmonary blood volume image at the same level shows peripheral perfusion defects corresponding to the opacities, with surrounding halos of increased perfusion (arrows). C, D, Images in a 57-year-old woman who presented with 7 days of fever, malaise, chills, cough, and increasing shortness of breath. On day 3 of admission, patient developed increasing oxygen requirement and elevated d-dimer level. C, CT scan of the upper lungs at lung windows shows ground-glass opacities in the central and peripheral upper lungs bilaterally, with regional low attenuation of a portion of the right upper lobe and superior segment of the right lower lobe (arrowheads). Vessels within the low attenuation region are diminutive in a regional pattern, while vessels in the areas of ground-glass opacity are dilated (arrows). D, Corresponding iodine map image shows regional decreased perfusion to the right lung (white arrowheads) and increased perfusion to the areas of ground-glass opacity, while there is also heterogeneous perfusion of the left upper lobe.

Figure 4:

A, B, Images in a 47-year-old woman with a history of metastatic breast cancer who initially presented with nausea, vomiting, and low-grade fever and tested positive for coronavirus disease 2019 (COVID-19) infection. Patient underwent CT pulmonary angiography (CT-PE) on day 4 of admission for acute intermittent tachycardia, lethargy, and new oxygen requirement. A, Axial CT image with lung windows through the left lower lobe at time of presentation shows abnormally dilated distal subsegmental vessels in the subpleural lung touching the pleural surface (arrowheads). B, Image at the same level of CT in the same patient 11 days prior shows normal vessel sizes and appearances, with a normal appearance of the subpleural lung. C, D, Images in a 64-year-old man who presented with acute onset of fatigue, headache, cough, fever, and shortness of breath and tested positive for COVID-19. On day 12 of admission, patient developed increasing oxygen requirement and CT-PE was performed. C, Axial CT image with lung windows through the right lower lung shows peripheral regional ground-glass opacity in the right lower lobe, with dilated segmental and subsegmental vessels supplying the region of opacified lung (arrows) and smaller diameters of vessels in unaffected lung. D, Image at the same level of a CT scan in the same patient approximately 3 months prior shows normal appearance of vessels.

Figure 5:

A, Image in an 84-year-old woman with a history of breast cancer who presented to the emergency department for fever, weakness, altered mental status, acute shortness of breath, and chest pain, for which CT pulmonary angiogram was obtained. Axial CT image shows dilated, nontapering, tortuous vessels in the posterior right lower lobe (arrowheads), some of which extend to the pleural surface. B, CT scan in the same patient shown at the same level 5 months prior shows normal vessels. C, Image in a 27-year-old woman who presented to the emergency department with acute shortness of breath and dyspnea on exertion. Patient was subsequently found to be coronavirus disease 2019–positive and had worsening tachypnea. Axial CT image through the lower lobes shows multiple dilated tortuous vessels within the lower lobes, with extension to the pleural surfaces (arrowheads).