COVID-19-Associated Carotid Atherothrombosis and Stroke

Abstract

We present a radiology-pathology case series of 3 patients with coronavirus disease 2019 (COVID-19) with acute ischemic stroke due to fulminant carotid thrombosis overlying mild atherosclerotic plaque and propose a novel stroke mechanism: COVID-associated carotid atherothrombosis.

FIG 1.

CT angiogram of cervical vessels showing thrombosis. Curved planar reformatted CTA neck images demonstrate adherent thrombus in the left mid-common carotid artery (patient 1) (A). The thrombus appears to start from the right carotid bifurcation and extend toward both the internal and external carotid arteries (patient 2) (B), and the left carotid bifurcation shows wedge-shaped intraluminal thrombus (patient 3) (C). Note the relatively minor mineralized and nonmineralized atherosclerotic plaque adjacent to the thrombus in each patient.

FIG 2.

Gross and microscopic pathology. A, Surgical view in patient 2. The blue circle indicates the area to which the thrombus was adherent, and the green circle indicates the area to which the contiguous portion of the thrombus was adherent. Arrows represent the larger portion of thrombus (blue), smaller portion of thrombus (green), and calcified plaque at the external carotid origin (red). B, Microscopic examination of a specimen from patient 2. Hematoxylin-eosin stain shows intimal thickening, plaque formation, and calcification. Higher magnification shows an area of intima with mononuclear inflammatory cells and evolving plaque formation. C, Microscopic examination of a specimen from patient 1. Low-power hematoxylin-eosin stain shows the thrombus adherent to the wall (upper portion is thrombus; lower portion is the wall). Higher-power view of an area of adherent thrombus shows the intima with inflammatory infiltrate as well as some degenerating cellular debris that may indicate apoptosis.