Recent case-series of small size implied a pathophysiological association between coronavirus disease 2019 (COVID-19) and severe large-vessel acute ischemic stroke. Given that severe strokes are typically associated with poor prognosis and can be very efficiently treated with recanalization techniques, confirmation of this putative association is urgently warranted in a large representative patient cohort to alert stroke clinicians, and inform pre- and in-hospital acute stroke patient pathways. We pooled all consecutive patients hospitalized with laboratory-confirmed COVID-19 and acute ischemic stroke in 28 sites from 16 countries. To assess whether stroke severity and outcomes (assessed at discharge or at the latest assessment for those patients still hospitalized) in patients with acute ischemic stroke are different between patients with COVID-19 and non-COVID-19, we performed 1:1 propensity score matching analyses of our COVID-19 patients with non-COVID-19 patients registered in the Acute Stroke Registry and Analysis of Lausanne Registry between 2003 and 2019. Between January 27, 2020, and May 19, 2020, 174 patients (median age 71.2 years; 37.9% females) with COVID-19 and acute ischemic stroke were hospitalized (median of 12 patients per site). The median National Institutes of Health Stroke Scale was 10 (interquartile range [IQR], 4–18). In the 1:1 matched sample of 336 patients with COVID-19 and non-COVID-19, the median National Institutes of Health Stroke Scale was higher in patients with COVID-19 (10 [IQR, 4–18] versus 6 [IQR, 3–14]), P =0.03; (odds ratio, 1.69 [95% CI, 1.08–2.65] for higher National Institutes of Health Stroke Scale score). There were 48 (27.6%) deaths, of which 22 were attributed to COVID-19 and 26 to stroke. Among 96 survivors with available information about disability status, 49 (51%) had severe disability at discharge. In the propensity score-matched population (n=330), patients with COVID-19 had higher risk for severe disability (median mRS 4 [IQR, 2–6] versus 2 [IQR, 1–4], P <0.001) and death (odds ratio, 4.3 [95% CI, 2.22–8.30]) compared with patients without COVID-19. Our findings suggest that COVID-19 associated ischemic strokes are more severe with worse functional outcome and higher mortality than non-COVID-19 ischemic strokes.

The antimicrobial functions of neutrophils are facilitated by a defensive armamentarium of proteins stored in granules, and by the formation of neutrophil extracellular traps (NETs). However, the toxic nature of these structures poses a threat to highly vascularized tissues, such as the lungs. Here, we identified a cell-intrinsic program that modified the neutrophil proteome in the circulation and caused the progressive loss of granule content and reduction of the NET-forming capacity. This program was driven by the receptor CXCR2 and by regulators of circadian cycles. As a consequence, lungs were protected from inflammatory injury at times of day or in mouse mutants in which granule content was low. Changes in the proteome, granule content and NET formation also occurred in human neutrophils, and correlated with the incidence and severity of respiratory distress in pneumonia patients. Our findings unveil a 'disarming' strategy of neutrophils that depletes protein stores to reduce the magnitude of inflammation.

Background and Purpose— Recanalization of the occluded artery is a primary goal in stroke treatment. Unfortunately, endovascular treatment is not always available, and tPA (tissue-type plasminogen activator) therapy is limited by its narrow therapeutic window; importantly, the rate of early arterial recanalization after tPA administration is low, especially for platelet-rich thrombi. The mechanisms for this tPA resistance are not well known. Since neutrophil extracellular traps (NETs) have been implicated in this setting, our aim was to study whether NET pharmacological modulation can reverse tPA resistance and the role of TLR4 (Toll-like receptor 4), previously related to NET formation, in thrombosis. Methods— To this goal, we have used a mouse photothrombotic stroke model, which produces a fibrin-free thrombus composed primarily of aggregated platelets and thrombi obtained from human stroke patients. Results— Our results demonstrate that (1) administration of DNase-I, which promotes NETs lysis, but not of tPA, recanalizes the occluded vessel improving photothrombotic stroke outcome; (2) a preventive treatment with Cl-amidine, impeding NET formation, completely precludes thrombotic occlusion; (3) platelet TLR4 mediates NET formation after photothrombotic stroke; and (4) ex vivo fresh platelet-rich thrombi from ischemic stroke patients are effectively lysed by DNase-I. Conclusions— Hence, our data open new avenues for recanalization of platelet-rich thrombi after stroke, especially to overcome tPA resistance.

Background and Purpose: The coronavirus disease 2019 (COVID-19) outbreak has added challenges to providing quality acute stroke care due to the reallocation of stroke resources to COVID-19. Case series suggest that patients with COVID-19 have more severe strokes; however, no large series have compared stroke outcomes with contemporary non–COVID-19 patients. Purpose was to analyze the impact of COVID-19 pandemic in stroke care and to evaluate stroke outcomes according to the diagnosis of COVID-19. Methods: Retrospective multicenter cohort study including consecutive acute stroke patients admitted to 7 stroke centers from February 25 to April 25, 2020 (first 2 months of the COVID-19 outbreak in Madrid). The quality of stroke care was measured by the number of admissions, recanalization treatments, and time metrics. The primary outcome was death or dependence at discharge. Results: A total of 550 acute stroke patients were admitted. A significant reduction in the number of admissions and secondary interhospital transfers was found. COVID-19 was confirmed in 105 (19.1%) patients, and a further 19 patients were managed as suspected COVID-19 (3.5%). No differences were found in the rates of reperfusion therapies in ischemic strokes (45.5% non–COVID-19, 35.7% confirmed COVID-19, and 40% suspected COVID-19; P =0.265). However, the COVID-19 group had longer median door-to-puncture time (110 versus 80 minutes), which was associated with the performance of chest computed tomography. Multivariate analysis confirmed poorer outcomes for confirmed or suspected COVID-19 (adjusted odds ratios, 2.05 [95% CI, 1.12–3.76] and 3.56 [95% CI, 1.15–11.05], respectively). Conclusions: This study confirms that patients with COVID-19 have more severe strokes and poorer outcomes despite similar acute management. A well-established stroke care network helps to diminish the impact of such an outbreak in stroke care, reducing secondary transfers and allowing maintenance of reperfusion therapies, with a minor impact on door-to-puncture times, which were longer in patients who underwent chest computed tomography.

PURPOSE: Our aim was to study the association between abnormal findings on chest and brain imaging in patients with coronavirus disease 2019 (COVID-19) and neurologic symptoms. MATERIALS AND METHODS: In this retrospective, international multicenter study, we reviewed the electronic medical records and imaging of hospitalized patients with COVID-19 from March 3, 2020, to June 25, 2020. Our inclusion criteria were patients diagnosed with Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infection with acute neurologic manifestations and available chest CT and brain imaging. The 5 lobes of the lungs were individually scored on a scale of 0-5 (0 corresponded to no involvement and 5 corresponded to .75% involvement). A CT lung severity score was determined as the sum of lung involvement, ranging from 0 (no involvement) to 25 (maximum involvement). RESULTS: A total of 135 patients met the inclusion criteria with 132 brain CT, 36 brain MR imaging, 7 MRA of the head and neck, and 135 chest CT studies. Compared with 86 (64%) patients without acute abnormal findings on neuroimaging, 49 (36%) patients with these findings had a significantly higher mean CT lung severity score (9.9 versus 5.8, P , .001). These patients were more likely to present with ischemic stroke (40 [82%] versus 11 [13%], P , .0001) and were more likely to have either ground-glass opacities or consolidation (46 [94%] versus 73 [84%], P ¼ .01) in the lungs. A threshold of the CT lung severity score of .8 was found to be 74% sensitive and 65% specific for acute abnormal findings on neuroimaging. The neuroimaging hallmarks of these patients were acute ischemic infarct (28%), intracranial hemorrhage (10%) including microhemorrhages (19%), and leukoencephalopathy with and/or without restricted diffusion (11%). The predominant CT chest findings were peripheral ground-glass opacities with or without consolidation. CONCLUSIONS: The CT lung disease severity score may be predictive of acute abnormalities on neuroimaging in patients with COVID-19 with neurologic manifestations. This can be used as a predictive tool in patient management to improve clinical outcome. ABBREVIATIONS: COVID-19 ¼ coronavirus disease 2019; GGOs ¼ ground-glass opacities; PRES ¼ posterior reversible encephalopathy syndrome; SARS-CoV-2 ¼ Severe Acute Respiratory Syndrome coronavirus 2; TIPIC ¼ Transient Perivascular Inflammation of the Carotid artery syndrome S evere Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) began in Wuhan, China, in December 2019 and has rapidly spread around the world to become a pandemic. 1 Extensive studies have described chest and brain imaging characteristics associated with coronavirus disease 2019 (COVID-19). 2-13 The hallmarks of COVID-19 infection on chest imaging