Lesson by SARS-CoV-2 disease (COVID-19): whole-body CT angiography detection of "relevant" and "other/incidental" systemic vascular findings

Abstract

Objectives: Increasing evidence suggests that SARS-CoV-2 infection may lead to severe and multi-site vascular involvement. Our study aimed at assessing the frequency of vascular and extravascular events' distribution in a retrospective cohort of 42 COVID-19 patients.

Methods: Patients were evaluated by whole-body CT angiography between March 16 and April 30, 2020. Twenty-three out of the 42 patients evaluated were admitted to the intensive care unit (ICU). Vascular and extravascular findings were categorized into "relevant" or "other/incidental," first referring to the need for immediate patient care and management. Student T-test, Mann-Whitney U test, or Fisher exact test was used to compare study groups, where appropriate.

Results: Relevant vascular events were recorded in 71.4% of cases (n = 30). Pulmonary embolism was the most frequent in both ICU and non-ICU cases (56.5% vs. 10.5%, p = 0.002). Ischemic infarctions at several sites such as the gut, spleen, liver, brain, and kidney were detected (n = 20), with multi-site involvement in some cases. Systemic venous thrombosis occurred in 30.9% of cases compared to 7.1% of systemic arterial events, the first being significantly higher in ICU patients (p = 0.002). Among incidental findings, small-sized splanchnic arterial aneurysms were reported in 21.4% of the study population, with no significant differences in ICU and non-ICU patients.

Conclusions: Vascular involvement is not negligible in COVID-19 and should be carefully investigated as it may significantly affect disease behavior and prognosis.

Key points: • Relevant vascular events were recorded in 71.4% of the study population, with pulmonary embolism being the most frequent event in ICU and non-ICU cases. • Apart from the lung, other organs such as the gut, spleen, liver, brain, and kidneys were involved with episodes of ischemic infarction. Systemic venous and arterial thrombosis occurred in 30.9% and 7.1% of cases, respectively, with venous events being significantly higher in ICU patients (p = 0.002). • Among incidental findings, small-sized splanchnic arterial aneurysms were reported in 21.4% of the whole population.

Keywords: COVID-19; CT angiography; Embolism; Infarction; Thrombosis.

Fig. 1

Axial thin-section baseline unenhanced lung CT scan in a 33-year-old patient who presented with fever and cough, ultimately requiring ICU admission due to significant worsening of respiratory failure. Diffuse bilateral confluent and patchy ground-glass and consolidative pulmonary opacities are evident from the lung apices (a, b) to the bases (c, d), with a total severity score of 20/24 (see text)

Fig. 2

WB-CTA in a 33-year-old patient (same case of Fig. 1) showing the presence of extensive embolic obstruction of the right (a) and left (b, multi-planar reconstruction) main branch of the pulmonary artery (a and b, respectively). Dilatation of the bronchial arteries is also appreciable (b, MPR reconstruction). This finding was likely suggestive of unrecognized subclinical recurrent or chronic PE (unremarkable clinical history, no previous CT imaging available). However, no indirect features compatible with chronic thromboembolic pulmonary hypertension, like deviation of the interventricular septum and mosaic perfusion, were detected, as respectively shown in panels c (axial section on the heart chambers) and d (min-IP coronal view of the lungs)

Fig. 3

WB-CTA showing an extensive thrombotic filling defect within the aortic arch (a) and bilateral kidney infarction (b) in a 57-year-old no-ICU patient with acute chest pain and sudden onset of discoloration of the upper limbs. Thrombosis of the distal inferior cava and iliac veins (c) along with the concomitance of left iliac artery partial thrombotic occlusion in a 68-year-old ICU patient with acute onset of lower limb edema

Fig. 4

Multi-site active bleeding in a 63-year-old ICU patient with sudden onset of dyspnea along with severe acute anemia. Arrows show contrast medium extravasation in the left carotid space (a), in the left rectus abdominis muscle (b), in the left psoas muscle and homolateral perirenal/posterior pararenal space (c), and the right iliac extra-peritoneal space (d)