Acute Cerebrovascular Events With COVID-19 Infection

Mandip S. Dhamoon, MD, DrPH; Alison Thaler, MD; Kapil Gururangan, MD; Amit Kohli, MD; Daniella Sisniega, MD; Danielle Wheelwright, RN; Connor Mensching, MS; Johanna T. Fifi, MD; Michael G. Fara, MD, PhD; Nathalie Jette, MD, MSc; Ella Cohen, BS; Priya Dave, BA; Aislyn C. DiRisio, BS; Jonathan Goldstein, BA; Emma M. Loebel, BA; Naomi A. Mayman, BS; Akarsh Sharma, MS, BS; Daniel S. Thomas, BBA; Ruben D. Vega Perez, MPH; Mark R. Weingarten, BA; Huei Hsun Wen, MD, MSCR; Stanley Tuhrim, MD; Laura K. Stein, MD


Stroke. 2021;52(1):48-56. 

In This Article


The data that support the findings of this study are available from the corresponding author upon reasonable request. We performed a retrospective observational study of consecutively admitted patients in the Mount Sinai Health System (MSHS) in New York, NY with discharge diagnosis of acute cerebrovascular events, including ischemic stroke (IS), transient ischemic attack, intracerebral hemorrhage (ICH), subarachnoid hemorrhage, and cerebral venous sinus thrombosis. MSHS serves a large and diverse population across New York City. MSHS comprises one Comprehensive Stroke Center with neurosurgical services and 5 Primary Stroke Centers, 3 of which offer 24/7 acute endovascular therapies and 2 of which also offer neurosurgical services, linked by a robust intrasystem transfer process for patients requiring acute stroke intervention and higher-level medical support. The Comprehensive Stroke Center and endovascular therapy–capable sites also receive referral transfers from several community hospitals throughout New York City and its greater metropolitan area. Of the 175 patients transferred for endovascular therapy evaluation with emergent large vessel occlusion in 2019, 103 underwent intervention, making up just over 47% of total MSHS endovascular therapy volumes.

In this study, we included patients admitted from March 1, 2020 through April 30, 2020. We routinely collect data for quality control purposes on all admitted patients with stroke in our health system as part of the Mount Sinai Stroke Registry, including stroke subtype and discharge disposition as defined below. For the purposes of this study, we expanded the data collection to gather additional data of interest during this study time period, under the approval of the Icahn School of Medicine at Mount Sinai Institutional Review Board, which waived the need for informed consent. In addition, to be able to calculate the proportion of admitted COVID-19 patients with stroke, we used our institutional data warehouse to identify all adult patients with COVID-19 hospitalized between March 1, 2020 and April 30, 2020. Patients were diagnosed with COVID-19 if they had at least one positive result for SARS-CoV-2 by nasopharyngeal swab, tracheal, or bronchial polymerase chain reaction during the hospitalization. In cases where clinical suspicion was high for COVID-19 and the initial test negative, polymerase chain reaction was routinely repeated to confirm clinical suspicion. If a patient had multiple nasopharyngeal polymerase chain reaction tests performed during the hospitalization, the patient was considered positive if at least one sample was positive for SARS-CoV-2 infection during hospitalization. In most cases, neurological assessment for acute stroke presentations was performed before reporting of COVID-19 testing.

All data (including demographic information, baseline comorbidities, baseline medications, medication administration during the hospitalization, all provider notes, all laboratory and diagnostic study results from the care provided during the hospitalization) were recorded systematically by clinically trained data abstractors after review of the entire record of the inpatient hospitalization available in the electronic health record. Standard forms based on modified Behavioral Risk Factor Surveillance System forms[11] were used to capture comorbidities. Trained vascular neurologists validated data entry by reviewing a random sample of patients.

Stroke subtype was categorized into IS, ICH, subarachnoid hemorrhage, transient ischemic attack, or cerebral venous sinus thrombosis. IS was further subtyped by mechanism based on modified TOAST (Trial of ORG 10172 in Acute Stroke Treatment) criteria:[12] small-vessel, large artery atherosclerosis, cardioembolic, cryptogenic, and other known cause. The subtype was determined after review of risk factor profiles, clinical features, and results of diagnostic tests, including computed tomography scan, magnetic resonance imaging, vascular imaging, ECG, echocardiography, and assessment of prothrombotic syndromes as relevant. Cryptogenic subtype was determined after excluding the subtypes of small-vessel, large artery atherosclerosis, cardioembolic, and other known cause. In cases with missing diagnostic information or conflicting stroke mechanisms, data review was performed by at least 2 vascular neurologists for adjudication. Vital signs and laboratory results closest to the time of stroke discovery were recorded, as were acute stroke treatments or interventions. Reperfusion outcomes following mechanical thrombectomy were reported according to scores on the Thrombolysis in Cerebral Infarction scale.

Findings from noncontrast head computed tomography, computed tomography angiogram of the head and neck, brain magnetic resonance imaging, and magnetic resonance angiogram of the head and neck were recorded using standardized forms summarizing reports read by trained attending neuroradiologists. Location of acute infarct or hemorrhage was recorded and stenosis or occlusion of intracranial or extracranial cervical vessels. Other treatments were summarized, including medical treatments related to COVID-19. Of note, at the beginning of the COVID-19 surge in New York City, our health system introduced a COVID-19 anticoagulation algorithm that recommended consideration of treatment-dose anticoagulation for patients with moderate or severe COVID-19. Patients were considered high risk based on oxygen requirement or elevations in D-dimer, creatinine, or C-reactive protein.

In-hospital outcomes were recorded, including neurological worsening (defined as an increase in neurological deficits according to recorded examinations by a neurologist), new IS or ICH (reported on follow up imaging), one of the following medical complications documented by the primary team: deep venous thrombosis, pulmonary embolism, myocardial infarction, intensive care unit admission, cardiac arrhythmia, hemodialysis, mechanical ventilation, tracheostomy, shock requiring vasoactive medications, goals of care decisions, and discharge disposition (home, in-hospital death, transfer to acute rehabilitation, transfer to subacute rehabilitation, discharge to hospice, or transfer to another hospital or inpatient ward).

Statistical Analysis

Using our institutional data warehouse data, we calculated the number of adults admitted to MSHS with COVID-19 and used the total number of patients with stroke from our stroke dataset to calculate the proportion of admitted COVID-19 patients with acute cerebrovascular disease. Using the stroke dataset, we summarized characteristics of consecutively admitted patients with stroke, reporting means and SDs for continuous variables, and frequencies and percentages for categorical variables. We examined demographic variables, medical comorbidities, stroke characteristics, imaging results, laboratory test results (including coagulation, hematologic, inflammatory, and autoimmune markers), in-hospital treatments, and outcomes among patients with stroke, stratifying by COVID-19 status and assessing significant differences in variable distributions between COVID-19-positive and COVID-19-negative using t-tests for continuous variables and χ 2 tests for categorical variables. Finally, using MSHS Stroke Registry data, we performed comparisons of stroke subtype and discharge disposition between the COVID-19 positive group and (1) stroke admissions during the same time period 1 year prior (March 1, 2019 through April 30, 2019) and (2) stroke admissions during 2019 (January 1 through December 31). For this comparison, we defined stroke subtype and discharge disposition based upon available data in the Stroke Registry. Using data from the entire year 2019, we calculated the average daily number of admissions and multiplied by 61 to calculate the expected number of stroke admissions from March 1, 2019 through April 30, 2019. All analyses were performed in SAS version 9.4 using a significance threshold of α=0.05.