COVID-19 related thrombi in ascending and descending thoracic aorta with peripheral embolization: a case report

Abstract

Background: COVID-19 (severe acute respiratory syndrome coronavirus 2) infected patients have increased risk for thrombotic events, which initially may have been under recognized. The existence of cardiovascular emboli can be directly life threatening when obstructing the blood flow to vital organs such as the brain or other parts of the body. The exact mechanism for this hypercoagulable state in COVID-19 patients yet remains to be elucidated.

Case summary: A 72-year-old man critically ill with COVID-19 was diagnosed with a free-floating and mural thrombus in the thoracic aorta. Subsequent distal embolization to the limbs led to ischaemia and necrosis of the right foot. Treatment with heparin and anticoagulants reduced thrombus load in the ascending and thoracic aorta.

Discussion: One-third of COVID-19 patients show major thrombotic events, mostly pulmonary emboli. The endothelial expression of angiotensin-converting enzyme-2 receptors makes it feasible that in patients with viraemia direct viral-toxicity to the endothelium of also the large arteries results in local thrombus formation. Up to date, prophylactic anticoagulants are recommended in all patients that are hospitalized with COVID-19 infections to prevent venous and arterial thrombotic complications.

Keywords: Anticoagulation; Aortic thrombus; Ascending aorta; COVID-19; Case report; Heparin; SARS-CoV2; Thoracic aorta.

Figure 1

COVID-19 related thrombi in the aorta. (A) Sagittal views of aortic computed tomography angiography displaying a mural thrombus in the aortic arch (left side, indicated by white arrow) and a free-floating thrombus in the distal thoracic aorta (right side, indicated by white arrow). (B) Computed tomography images displaying the situation after 7 days of Heparin treatment. Note: The free-floating thrombus in the thoracic aorta has decreased in size (right side, indicated by transparent arrow), while the thrombus in the arch appears similar in size. White arrow indicates a thrombus. Transparent arrow indicates (partial) thrombus resolution.

Figure 2

Distal embolization in the legs but no other parts of the body. Computed tomography images from other organs and extremities showing (A) absence of thrombi in the upper leg vasculature (transparent arrows), (B) presence of a stop in the right posterior tibial artery (white arrow) but not in the left posterior tibial artery (transparent arrow), (C) no cerebral vascular involvement, (D) adequate perfusion of the renal arteries (transparent arrows), and (E) good blood flow in the mesenteric and femoral arteries (transparent arrows). Transparent arrow indicates perfusion. White arrow indicates a stop.

Figure 3

Distal embolization of the right leg resulted in necrosis of the foot. (A) Image of necrotic digit 1–3 right as observed in the second week post-ICU admission. (B) Image of the necrotic right foot with partial necrosis of also digit 4 as observed in the outpatient setting 10 weeks after initial diagnosis.