COVID-19 patients are “hypercoagulable and at an increased risk for stroke”


The association between COVID-19 and the increased incidence of stroke continues to grow. Situated within the pandemic’s epicentre, Kurt Yaeger and J Mocco, neurosurgeons at Mount Sinai Health System (New York, USA), discuss the unprecedented volume of stroke patients they have received over the last month. Speaking to NeuroNews, they speculate that many of these large-vessel strokes are a result of coronavirus-induced blood clotting.

J Mocco new york
J Mocco

The novel coronavirus (SARS-CoV-2) and its associated disease, COVID-19, has taken over New York City. Since the first reported cases at the beginning of March, we have witnessed exponential spread with case numbers exceeding 220,000 and related deaths of more than 12,0001. By 20th March, Governor Andrew Cuomo ordered nonessential businesses to be closed and for employees to quarantine at home. Concurrently, health systems across the city have diverted an enormous amount of resources to the care of critically ill patients with respiratory and other systemic complications of COVID-19. During this surge, we have seen a significant increase in the ischaemic stroke burden within our NYC health system, with a high incidence of COVID-19 positive patients.

Early reports from Wuhan China described COVID-19 as a proinflammatory and prothrombotic disease, with an increased risk of pulmonary embolism, deep vein thrombosis, and ischaemic stroke2-3. This led the American Stroke Association to release emergency guidance regarding stroke care in US stroke centres during this pandemic4. Such recommendations included: limiting care of stroke patients to essential personnel only, wearing personal protective equipment (PPE) with all patient interactions, and triaging only the most critical stroke patients to the intensive care units (ICUs). Remote telestroke options were also emphasised in order to maintain social distance between possibly infected patients and healthcare workers.

We would highlight that stroke is not only a late sequalae of COVID-19, but that emergent large vessel occlusion (ELVO) can be an early stage or even a presenting symptom. In less than a month, we triaged 45 patients throughout our health system with ELVO, substantially greater than our expected institutional volume. Of these patients, half tested positive for COVID-19. These patients also tended to be younger than typical ELVO patients. Furthermore, we noted an association with the number of ELVO presenting in a given borough with the prevalence of COVID-19 in that borough. Queens, for example, had the highest incidence of both ELVO and COVID-19 during this period.

Kurt Yaeger

While the time period is too short to draw definitive conclusions, our observations support the hypothesis that COVID-19 patients are hypercoagulable and at an increased risk for stroke. Fortunately, approximately half of the ELVO patients were candidates for endovascular reperfusion. Additionally, our rate of successful reperfusion in these patients remains consistent with pre-COVID data. By taking enhanced precautions, we have been able to ensure the continued safety of the thrombectomy team. This has been accomplished by maintaining a COVID-19 specific angiography suite, limiting personnel in the procedural room, and constant use of full airborne PPE for every case.

Despite increased infection risks, massive systemic changes to the healthcare environment, and higher rates of stroke in New York City during this period, we have observed that timely thrombectomy for ELVO patients appears to be safe, effective, and technically feasible. While we hope this crisis to be transitory, NYC may be a harbinger for other large cities.

J Mocco is a neurosurgeon at Mount Sinai Health System, New York, USA, where Kurt Yaeger is a resident of neurosurgery and a fellow of neuroendovascular surgery.


  2. Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, et al. Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus-Infected Pneumonia in Wuhan, China. JAMA. 2020
  3. Guo W, Li M, Dong Y, Zhou H, Zhang Z, Tian C, et al. Diabetes is a risk factor for the progression and prognosis of COVID-19. Metab. Res. Rev. 2020;e3319.
  4. Temporary Emergency Guidance to US Stroke Centers During the COVID-19 Pandemic. 2020



Please enter your comment!
Please enter your name here