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. 2022 Nov;43(11):6179-6183.
doi: 10.1007/s10072-022-06307-1. Epub 2022 Aug 3.

Carotid free-floating thrombus during COVID-19 vaccine era: causality or not?

Ludovica Ferraù #  1 , Masina Cotroneo  1 , Cristina Dell'Aera  1 , Fabrizio Giammello #  2   3 , Francesco Grillo  1 , Teresa Brizzi  1 , Antonio Pitrone  4 , Sergio Lucio Vinci  4 , Rosa Fortunata Musolino  1 , Paolino La Spina  1
Affiliations

Carotid free-floating thrombus during COVID-19 vaccine era: causality or not?

Ludovica Ferraù et al. Neurol Sci. 2022 Nov.

Abstract

Carotid free-floating thrombus (FFT) is very rarely diagnosed in patients with acute ischemic stroke. It is a real clinical emergency due to the significant risk of death associated with thromboembolic complications. Herein, we present three patients with ischemic stroke caused by carotid FFT after less than 20 days from administration of mRNA vaccine BNT162b1 (Pfizer/BioNTech) for Severe Acute Respiratory Syndrome-CoronaVirus 2 (SARS-CoV-2). To our knowledge, these are the first cases reporting carotid FTT following SARS-CoV-2 vaccination.

Keywords: Acute ischemic stroke; COVID-19 vaccine; Free-floating thrombus; SARS-CoV-2; mRNA vaccine BNT162b1.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Case n. 1. A, B Brain computed tomography (CT) revealing right occipito-temporal acute ischemic stroke (AIS). C Computed tomography angiography (CTA) showing a free-floating thrombus (FFT) in the right internal carotid artery (ICA) with severe plaque > 80% stenosis, measured with North American Symptomatic Carotid Endarterectomy Trial (NASCET) method (red arrow). D, E Magnetic resonance imaging (MRI) showing stability of infarction in T2-weighted images. F Follow-up CTA demonstrating the complete resolution of FFT in the very same position (red arrow)
Fig. 2
Fig. 2
Case n. 2. A, B MRI showing left fronto-parietal AIS on diffusion-weighted imaging (DWI). C CTA demonstrating hypodense plaque in left common carotid artery (CCA) with a NASCET stenosis of 70% (red arrow). D, E Digital subtraction angiography (DSA) performed after 24 h with carotid artery stenting (CAS) procedure. F Abdomen CTA showing additional FFT in abdominal aorta (red arrow)
See this image and copyright information in PMC

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