Late acute pulmonary embolism after mild Coronavirus Disease 2019 (COVID-19): a case series

Abstract

In late 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged as the cause of a cluster of pneumonia cases in China, and the corresponding disease was designated as Coronavirus Disease 2019 (COVID-19), spreading quickly around the world resulting in a pandemic. COVID-19 is associated with a set of coagulation abnormalities that increase the risk of thromboembolic events, especially in patients with severe/critical disease. We describe a series of five cases of mild COVID-19, treated in an outpatient clinic, which, after an apparent clinical improvement, developed acute pulmonary embolism (APE) between the third and the fourth week after the onset of symptoms, when they are mostly related to acute illness disappearance. Thromboembolic events are also a potential complication of mild COVID-19 and can manifest later in the disease course. This finding raises discussion about the prevention of thromboembolic events in selected group of patients with mild COVID-19.

Figure 1. CT pulmonary angiography findings of patients with mild COVID-19 complicated with acute pulmonary embolism. In patient 1, filling defects (arrow) are observed in the arterial branches for the lingula and the lower left lobe (1a and 1b) on the CT pulmonary angiography. Filling failure (arrow) in the subsegmental arterial branch to the right lower lobe was revealed by patient 2’s CT pulmonary angiography (1c and 1d). A non-occlusive filling defect (arrow) was observed in the right and left descending pulmonary arteries as well as its segmental and subsegmental branches on the CT pulmonary angiography of patient 3 (1e and 1f). In case of patient 4, the CT pulmonary angiography showed filling failure (arrow) of segmental branches of the pulmonary artery located in the right lower lobe, as well as in the left pulmonary artery extending to the upper and lingual lobar artery, and in some segmental branches of the left lower lobe (1g and 1h). Patient 5’s CT pulmonary angiography (1i and 1j) showed filling failure (arrow) of left and right lobar arteries, as well as its segmental and subsegmental branches.