COVID-19-associated ischaemic stroke due to underlying carotid artery thrombosis in a healthy young woman.

SARS-CoV-2 has proven its versatility in host presentations; one such presentation is a hypercoagulable state causing large-vessel thrombosis. We report a case on a previously asymptomatic COVID-19-positive patient presenting with an acute ischaemic stroke and an incidental left internal carotid artery thrombus. The patient's medical, social and family history and hypercoagulability screening excluded any other explanation for the left carotid thrombus or stroke, except for testing positive for the COVID-19. This case explores the known hypercoagulable state associated with COVID-19 and the effect of the virus on the host's immune response. It also questions whether administration of recombinant tissue plasminogen activator (t-PA), according to the American Heart Association guidelines, following a negative head CT for haemorrhagic stroke is safe without prior extended imaging in this patient population. We recommend, in addition to obtaining a non-contrast CT scan of the brain, a CT angiogram or carotid duplex of the neck be obtained routinely in patients with COVID-19 exhibiting stroke symptoms before t-PA administration as the effects may be detrimental. This recommendation will likely prevent fragmentation and embolisation of an undetected carotid thrombus.

Intraluminal carotid thrombosis and acute ischemic stroke associated with COVID-19.

COVID-19 (Coronavirus disease 2019) caused by SARS-CoV-2 has a diverse constellation of neurological manifestations that include encephalopathy, stroke, Guillain-Barré syndrome, myelitis, and encephalitis. Intraluminal carotid thrombi (ILT) are infrequent lesions seen in only 1.6% of patients with acute ischemic stroke. Underlying atherosclerosis is the most common lesion associated with ILT formation. However, with COVID-19, we have encountered ILT in patients without significant atherosclerotic disease. The endothelial inflammation and hypercoagulable state associated with COVID-19 pose a risk of arterial and venous thromboembolism and could have contributed to this presentation although the exact pathophysiology and optimal treatment of ILT in COVID-19 remain elusive. Herein, we present a series of ischemic stroke patients with carotid ILT in the setting of a recent SARS-CoV-2 infection.

Pulmonary venous thrombosis in a patient with COVID-19 infection.

OBJECTIVES: Infection with the SARS-COV2 virus (COVID-19) may be complicated by thrombotic diathesis. This complication often involves the pulmonary microcirculation. While macrovascular thrombotic complications of the lung may include pulmonary artery embolism, pulmonary artery thrombus in situ has also been hypothesized. Pulmonary vein thrombosis has not been described in this context. METHODS/RESULTS: Herein, we provide a case of an otherwise healthy male who developed an ischemic stroke with left internal carotid thrombus. Further imaging revealed pulmonary emboli with propagation through the pulmonary veins into the left atrium. This left atrial thrombus provides a source of atypical "paradoxic arterial embolism". CONCLUSIONS: Thrombotic outcomes in the setting of severe COVID 19 pneumonia may include macrovascular venous thromboembolism, microvascular pulmonary vascular thrombosis and arterial thromboembolism. Pulmonary vein, herein described, provides further mechanistic pathway for potential arterial embolic phenomenon.