Advances in Management of the Stroke Etiology One-Percenters.

PURPOSE OF REVIEW: Uncommon causes of stroke merit specific attention; when clinicians have less common etiologies of stoke in mind, the diagnosis may come more easily. This is key, as optimal management will in many cases differs significantly from "standard" care. RECENT FINDINGS: Randomized controlled trials (RCT) on the best medical therapy in the treatment of cervical artery dissection (CeAD) have demonstrated low rates of ischemia with both antiplatelet and vitamin K antagonism. RCT evidence supports the use of anticoagulation with vitamin K antagonism in "high-risk" patients with antiphospholipid antibody syndrome (APLAS), and there is new evidence supporting the utilization of direct oral anticoagulation in malignancy-associated thrombosis. Migraine with aura has been more conclusively linked not only with increased risk of ischemic and hemorrhagic stroke, but also with cardiovascular mortality. Recent literature has surprisingly not provided support the utilization of L-arginine in the treatment of patients with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS); however, there is evidence at this time that support use of enzyme replacement in patients with Fabry disease. Additional triggers for reversible cerebral vasoconstriction syndrome (RCVS) have been identified, such as capsaicin. Imaging of cerebral blood vessel walls utilizing contrast-enhanced MRA is an emerging modality that may ultimately prove to be very useful in the evaluation of patients with uncommon causes of stroke. A plethora of associations between cerebrovascular disease and COVID-19 have been described. Where pertinent, authors provide additional tips and guidance. Less commonly encountered conditions with updates in diagnosis, and management along with clinical tips are reviewed.

Intravenous thrombolysis for acute ischemic stroke during two COVID-19 outbreaks in China: Wuhan pandemic and Beijing pandemic.

INTRODUCTION: The COVID-19 pandemic has had an impact on the emergency department (ED). Door-to-needle time (DNT) could be prolonged for intravenous thrombolysis (IVT) treatment. We aimed to investigate the impact of two COVID-19 pandemics on the workflow of IVT in our neurovascular ED. METHOD: We performed a retrospective analysis of patients who received IVT treatment in the neurovascular ED of Beijing Tiantan Hospital, Beijing, from January 20, 2020, to October 30, 2020, covering two COVID-19 pandemics in China. The time-based performances of IVT treatment including onset-to-arrival time, arrival-to-CT time, CT-to-needle time, door-to-needle time, and onset-to-needle time were recorded. Data on clinical characteristics and imaging information were also collected. RESULTS: Four hundred forty patients that received IVT were enrolled in this study. The number of patients admitted to our neurovascular ED began to decrease in December 2019 and was the lowest in April 2020 (n = 95). Longer DNT (Wuhan pandemic: 49.00 [35.00, 64.00] min; Beijing pandemic: 55.00 [45.50, 77.00] min) interval delays were observed during the two pandemics (p = .016). More patients admitted during the two pandemics had an 'unknown' subtype (Wuhan pandemic: 21.8%; Beijing pandemic: 31.4%. p = .008). The percentage of the cardiac embolism subtype was higher during the Wuhan pandemic (20.0%) than during other periods. The median admission NIHSS score increased during the Wuhan pandemic and the Beijing pandemic (8.00 [4.00, 12.00], 7.00 [4.50, 14.00], respectively, p < .001). CONCLUSION: The number of patients who received IVT decreased during the Wuhan pandemic. Higher admission NIHSS scores and prolonged DNT intervals were also observed during the Wuhan pandemic and the Beijing pandemic.

Antithrombotic therapy in the management of hospitalised patients with COVID-19.

Hospitalised patients with coronavirus disease 2019 (COVID-19) are at a significantly higher risk of having thromboembolic events while in hospital and in the immediate post-hospital discharge period. Based on early data from observational studies, multiple high quality randomised controlled trials have been conducted worldwide to evaluate optimal thromboprophylaxis regimens to reduce thromboembolism and other COVID-19-related adverse outcomes in hospitalised patients. The International Society on Thrombosis and Haemostasis has published evidence-based guideline recommendations using established methodology for the management of antithrombotic therapy of COVID-19 patients, both in-hospital and in the immediate post-hospital discharge period. A good clinical practice statement supplemented these guidelines based on topics for which there was no or limited high-quality evidence. This review summarises the main recommendations of these documents to serve as a quick access tool for hospital doctors to use in their everyday practice when treating COVID-19 patients.

Racial and ethnic differences in pharmacotherapy to prevent coronary artery disease and thrombotic events.

Awareness of racial/ethnic disparities represents a key challenge for healthcare systems that attempt to provide effective healthcare and to reduce existing inequalities in the use of and adherence to guideline-recommended cardiovascular drugs to improve clinical outcomes for cardiovascular disease (CVD). In this review, we describe important racial/ethnic differences between and within ethnic groups in the prevalence, risk factors, haemostatic factors, anti-inflammatory and endothelial markers, recurrence, and outcomes of CVD. We discuss important differences in the selection, doses, and response [efficacy and adverse drug reactions (ADRs)] in ethnically diverse patients treated with antithrombotics or lipid-lowering drugs. Differences in drug response are mainly related to racial/ethnic differences in the frequency of polymorphisms in genes encoding drug-metabolizing enzymes (DMEs) and drug transporters. These polymorphisms markedly influence the pharmacokinetics, dose requirements, and safety of warfarin, clopidogrel, and statins. This review aims to support a better understanding of the genetic differences between and among populations to identify patients who may experience an ADR or a lack of drug response, thus optimizing therapy and improving outcomes. The greater the understanding of the differences in the genetic variants of DMEs and transporters that determine the differences in the exposure, efficacy, and safety of cardiovascular drugs between races/ethnicities, the greater the probability that personalized medicine will become a reality.

Antiphospholipid syndrome, antiphospholipid antibodies, and stroke.

Antiphospholipid syndrome (APS) is a prothrombotic autoimmune disease with heterogeneous clinicopathological manifestations and is a well-established cause of acute ischemic stroke (AIS) and transient ischemic attack (TIA), particularly in younger patients. There is growing recognition of a wider spectrum of APS-associated cerebrovascular lesions, including white matter hyperintensities, cortical atrophy, and infarcts, which may have clinically important neurocognitive sequalae. Diagnosis of APS-associated AIS/TIA requires expert review of clinical and laboratory information. Management poses challenges, given the potential for substantial morbidity and recurrent thrombosis, additional risk conferred by conventional cardiovascular risk factors, and limited evidence base regarding optimal antithrombotic therapy for secondary prevention. In this review, we summarize key features of APS-associated cerebrovascular disorders, with focus on clinical and laboratory aspects of diagnostic evaluation. The current status of prognostic markers is considered. We review the evidence base for antithrombotic treatment in APS-associated stroke and discuss uncertainties, including the optimal intensity of anticoagulation and efficacy of direct oral anticoagulants. Clinical practice recommendations are provided, covering antithrombotic treatment, supportive management, and options for anticoagulant-refractory cases, and we highlight the benefits of adopting a considered, multidisciplinary team approach.

The effect of antithrombotic treatment on mortality in patients with acute infection: A meta-analysis of randomized clinical trials.

BACKGROUND AND AIMS: Acute infections cause relevant activation of innate immunity and inflammatory cascade. An excessive response against pathogens has been proved to trigger the pathophysiological process of thrombo-inflammation. Nevertheless, an association between the use of antithrombotic agents and the outcome of critically ill patients with infectious diseases is lacking. The aim of this meta-analysis is to determine the impact of antithrombotic treatment on survival of patients with acute infective disease. METHODS: MEDLINE, Embase, Cinahl, Web of Science and Cochrane Central Register of Controlled Trials (CENTRAL) databases were systematically searched from inception to March 2021. We included randomized controlled trials (RCTs) that evaluated any antithrombotic agent in patients with infectious diseases other than COVID-19. Two authors independently performed study selection, data extraction and risk of bias evaluation. The primary outcome was all-cause mortality. Summary estimates for mortality were calculated using the inverse-variance random-effects method. RESULTS: A total of 16,588 patients participating in 18 RCTs were included, of whom 2141 died. Four trials evaluated therapeutic-dose anticoagulation, 1 trial prophylactic-dose anticoagulation, 4 trials aspirin, and 9 trials other antithrombotic agents. Overall, the use of antithrombotic agents was not associated with all-cause mortality (relative risk 0.96; 95% confidence interval, 0.90-1.03). CONCLUSIONS: The use of antithrombotics is not associated with all-cause mortality in patients with infectious disease other than COVID-19. Complex pathophysiological interplays between inflammatory and thrombotic pathways may explain these results and need further investigation. REGISTRATION: PROSPERO, CRD42021241182.

Comprehensive collection of COVID-19 related prosthetic valve failure: a systematic review.

Since the beginning of the SARS-CoV-2 (COVID-19) pandemic, correlation of venous thromboembolism (VTE) and COVID-19 infection has been well established. Increased inflammatory response in the setting of COVID-19 infection is associated with VTE and hypercoagulability. Venous and arterial thrombotic events in COVID-19 infection have been well documented; however, few cases have been reported involving cardiac valve prostheses. In this review, we present a total of eight cases involving COVID-19-related prosthetic valve thrombosis (PVT), as identified in a systematic review. These eight cases describe valve position (mitral versus aortic) and prosthesis type (bioprosthetic versus mechanical), and all cases demonstrate incidents of PVT associated with simultaneous or recent COVID-19 infection. None of these eight cases display obvious non-adherence to anticoagulation; five of the cases occurred greater than three years after the most recent valve replacement. Our review offers insights into PVT in COVID-19 infected patients including an indication for increased monitoring in the peri-infectious period. We explore valve thrombosis as a mechanism for prosthetic valve failure. We describe potential differences in antithrombotic strategies that may offer added antithrombotic protection during COVID-19 infection. With the growing population of valve replacement patients and recurring COVID-19 infection surges, it is imperative to explore relationships between COVID-19 and PVT.

Assessing the safety of continued perioperative antithrombotic therapy in endoscopic airway surgery for laryngotracheal stenosis.

PURPOSE: Given the increasing utilization of endoscopic surgery, particularly for airway stenosis management in the era of COVID-19 due to prolonged intubation, it is important to examine whether continuing antithrombotic therapy perioperatively influences bleeding complications. We examined the impact of perioperative antithrombotic use on postoperative bleeding complications following endoscopic airway surgery for laryngotracheal stenosis. MATERIALS AND METHODS: Retrospective study from January 2016 to December 2021 of cases of patients ≥18 years who underwent endoscopic airway surgery for posterior glottic, subglottic, and tracheal stenosis at a single institution. Cases were excluded if they were an open airway surgery. The primary outcome was the occurrence of postoperative bleeding complications across cases of patients naive to and on baseline antithrombotic therapy, and those with preoperative continuation versus cessation of antithrombotic therapy. RESULTS: 258 cases across 96 patients met inclusion criteria. Of these 258 cases, 43.4 % (n = 112) were performed for patients on baseline antithrombotic therapy and 56.6 % (n = 146) for those not on antithrombotic therapy. Likelihood of perioperative continuation of apixaban was 0.052 (odds ratio, 95 % Confidence Interval: 0.002-0.330, p < 0.001). Likelihood of perioperative continuation of aspirin was 9.87 (odds ratio, 95 % Confidence Interval: 2.32-43.0, p < 0.001). Two instances of postoperative bleeding were found: both in patients who were on aspirin without perioperative cessation for COVID-related coagulopathy. CONCLUSIONS: Our findings suggest that perioperative continuation of aspirin is relatively safe in the setting of endoscopic surgery for airway stenosis management. Prospective investigations to increase understanding of perioperative antithrombotics for COVID-related coagulopathy are warranted.

3-Arylidene-2-oxindoles as GSK3ß inhibitors and anti-thrombotic agents.

Development of novel agents that prevent thrombotic events is an urgent task considering increasing incidence of cardiovascular diseases and coagulopathies that accompany cancer and COVID-19. Enzymatic assay identified novel GSK3ß inhibitors in a series of 3-arylidene-2-oxindole derivatives. Considering the putative role of GSK3ß in platelet activation, the most active compounds were evaluated for antiplatelet activity and antithrombotic activity. It was found that GSK3ß inhibition by 2-oxindoles correlates with inhibition of platelet activation only for compounds 1b and 5a. Albeit, in vitro antiplatelet activity matched well with in vivo anti-thrombosis activity. The most active GSK3ß inhibitor 5a exceeds antiplatelet activity of acetylsalicylic acid in vitro by 10.3 times and antithrombotic activity in vivo by 18.7 times (ED50 7.3 mg/kg). These results support the promising role of GSK3ß inhibitors for development of novel antithrombotic agents.

In-Hospital Delays for Acute Stroke Treatment Delivery During the COVID-19 Pandemic.

BACKGROUND: We investigated the impact of regionally imposed social and healthcare restrictions due to coronavirus disease 2019 (COVID-19) to the time metrics in the management of acute ischemic stroke patients admitted at the regional stroke referral site for Central South Ontario, Canada. METHODS: We compared relevant time metrics between patients with acute ischemic stroke receiving intravenous tissue plasminogen activator (tPA) and/or endovascular thrombectomy (EVT) before and after the declared restrictions and state of emergency imposed in our region (March 17, 2020). RESULTS: We identified a significant increase in the median door-to-CT times for patients receiving intravenous tPA (19 min, interquartile range (IQR): 14-27 min vs. 13 min, IQR: 9-17 min, p = 0.008) and/or EVT (20 min, IQR: 15-33 min vs. 11 min, IQR: 5-20 min, p = 0.035) after the start of social and healthcare restrictions in our region compared to the previous 12 months. For patients receiving intravenous tPA treatment, we also found a significant increase (p = 0.005) in the median door-to-needle time (61 min, IQR: 46-72 min vs. 37 min, IQR: 30-50 min). No delays in the time from symptom onset to hospital presentation were uncovered for patients receiving tPA and/or endovascular reperfusion treatments in the first 1.5 months after the establishment of regional and institutional restrictions due to the COVID-19 pandemic. CONCLUSION: We detected an increase in our institutional time to treatment metrics for acute ischemic stroke patients receiving tPA and/or endovascular reperfusion therapies, related to delays from hospital presentation to the acquisition of cranial CT imaging for both tPA- and EVT-treated patients, and an added delay to treatment with tPA.

Délais dans le traitement en milieu hospitalier des AVC aigus dans le contexte de la pandémie de COVID-19. CONTEXTE: Nous nous sommes penchés, dans le contexte de la pandémie de COVID-19, sur l'impact de restrictions régionales imposées dans le domaine social et dans les soins de santé sur les délais de prise en charge de patients victimes d'un AVC aigu. À noter que ces patients ont été admis dans un centre régional de traitement des AVC situé dans le centre-ouest de l'Ontario (Canada). MÉTHODES: Nous avons comparé entre eux les délais de prise en charge de patients ayant bénéficié d'activateurs tissulaires du plasminogène par intraveineuse (tPA) et/ou d'une procédure de thrombectomie endovasculaire (TE) avant et après la mise sur pied de restrictions et l'imposition d'un état d'urgence sanitaire dans notre région (17 mars 2020). RÉSULTATS: Après la mise sur pied de ces restrictions, nous avons identifié, par rapport aux 12 mois précédent, une augmentation notable des délais médians entre l'arrivée à l'hôpital et un examen de tomodensitométrie dans le cas de patients bénéficiant de tPA (19 minutes, EI : 14­27 minutes contre 13 minutes, EI : 9­17 minutes ; p = 0,008) et/ou d'une procédure de TE (20 minutes, EI : 15­33 minutes contre 11 minutes, EI : 5­20 minutes ; p = 0,035). Pour ce qui est des patients bénéficiant de tPA, nous avons également observé une augmentation importante (p = 0,005) des délais médians entre leur arrivée à l'hôpital et l'injection d'un traitement (61 minutes, EI : 46­72 minutes contre 37 minutes, EI : 30­50 minutes). Enfin, dans le premier mois et demi suivant la mise sur pied des restrictions régionales et institutionnelles attribuables à la pandémie de COVID-19, aucun délai supplémentaire entre l'apparition des premiers symptômes d'un AVC et l'arrivée à l'hôpital n'a été remarqué pour des patients bénéficiant de tPA et/ou d'une procédure de TE. CONCLUSION: En somme, nous avons détecté une augmentation de nos délais de traitement dans le cas de patients victimes d'un AVC aigu ayant bénéficié de tPA et/ou d'une procédure de TE. Cela peut être attribué à une augmentation des délais de présentation à l'hôpital mais aussi à des délais dans l'obtention d'images de tomodensitométrie pour des patients traités avec des tPA et une procédure de TE, sans compter des délais accrus pour bénéficier d'un traitement de tPA.

Management, control, and decision making in unexpected recurrent venous thromboembolism in COVID-19: a case report.

BACKGROUND: Coronavirus disease 2019 was spread worldwide, as a pandemic, from December 2019. Venous thromboembolism events can inflict patients with coronavirus disease 2019 during the hospitalization or convalescent period. Therefore, monitoring of these patients, in terms of venous thromboembolism events signs and symptoms, and timely management of antithrombotic agents are of great importance. CASE REPORT: A 45-year-old Iranian man, who is the first author of this case report, was infected by severe acute respiratory syndrome coronavirus 2 and displayed the typical signs and symptoms of coronavirus disease 2019. Although reverse transcription polymerase chain reaction for coronavirus disease 2019, and specific immunoglobulin M and immunoglobulin G against severe acute respiratory syndrome coronavirus 2, were negative at first, chest computed tomography scan showed the characteristic pattern of lung involvement of a coronavirus disease 2019 infection including bilateral and multilobar ground-glass opacities. At that time, there were no signs or symptoms of deep-vein thrombosis or pulmonary thromboembolism, so these were not investigated. About 30 hours after hospital discharge, the patient presented back to the hospital with acute-onset chest pain. We instantly tested his blood for D-dimer, and sent him to take a Doppler sonography of his lower legs and a chest computed tomography angiography in search of pulmonary thromboembolism and deep-vein thrombosis. Although we could confirm pulmonary thromboembolism with computed tomography angiography in our patient, there were no signs or symptoms of venous thromboembolism in his lower legs, and color Doppler sonography of lower limbs was normal. So, the patient was treated with rivaroxaban as an antithrombotic agent. After some days, he was discharged in good condition. About 1 month later, he was referred to our hospital because of left lower limb edema. Although he was under antithrombotic therapy, color Doppler sonography of lower limbs revealed acute deep-vein thrombosis of the left leg. Hence, we decided to shift antithrombotic therapy from rivaroxaban to warfarin, as it is more potent than rivaroxaban in recurrent venous thromboembolism and when taking new oral anticoagulants. Unlike rivaroxaban, which needs no blood test to monitor its efficacy but has a warning for signs and symptoms of bleeding, warfarin therapy must be monitored carefully by regular blood tests for prothrombin time and international normalized ratio to maintain them in the therapeutic range. The patient was informed about the bleeding cautions, and required regular check of prothrombin time and international normalized ratio to maintain them in the proper and advised range of treatment (international normalized ratio therapeutic range 2-3). CONCLUSION: In the case of unexpected recurrent venous thromboembolism in coronavirus disease 2019, especially when patients are taking rivaroxaban or other new oral anticoagulants, such drugs should be substituted by warfarin, with routine follow-up, to maintain the value of prothrombin time and international normalized ratio within the therapeutic range.

Trial of Endovascular Therapy for Acute Ischemic Stroke with Large Infarct.

BACKGROUND: The role of endovascular therapy for acute stroke with a large infarction has not been extensively studied in differing populations. METHODS: We conducted a multicenter, prospective, open-label, randomized trial in China involving patients with acute large-vessel occlusion in the anterior circulation and an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower values indicating larger infarction) or an infarct-core volume of 70 to 100 ml. Patients were randomly assigned in a 1:1 ratio within 24 hours from the time they were last known to be well to undergo endovascular therapy and receive medical management or to receive medical management alone. The primary outcome was the score on the modified Rankin scale at 90 days (scores range from 0 to 6, with higher scores indicating greater disability), and the primary objective was to determine whether a shift in the distribution of the scores on the modified Rankin scale at 90 days had occurred between the two groups. Secondary outcomes included scores of 0 to 2 and 0 to 3 on the modified Rankin scale. The primary safety outcome was symptomatic intracranial hemorrhage within 48 hours after randomization. RESULTS: A total of 456 patients were enrolled; 231 were assigned to the endovascular-therapy group and 225 to the medical-management group. Approximately 28% of the patients in both groups received intravenous thrombolysis. The trial was stopped early owing to the efficacy of endovascular therapy after the second interim analysis. At 90 days, a shift in the distribution of scores on the modified Rankin scale toward better outcomes was observed in favor of endovascular therapy over medical management alone (generalized odds ratio, 1.37; 95% confidence interval, 1.11 to 1.69; P = 0.004). Symptomatic intracranial hemorrhage occurred in 14 of 230 patients (6.1%) in the endovascular-therapy group and in 6 of 225 patients (2.7%) in the medical-management group; any intracranial hemorrhage occurred in 113 (49.1%) and 39 (17.3%), respectively. Results for the secondary outcomes generally supported those of the primary analysis. CONCLUSIONS: In a trial conducted in China, patients with large cerebral infarctions had better outcomes with endovascular therapy administered within 24 hours than with medical management alone but had more intracranial hemorrhages. (Funded by Covidien Healthcare International Trading [Shanghai] and others; ANGEL-ASPECT ClinicalTrials.gov number, NCT04551664.).

Pharmacology of Heparin and Related Drugs: An Update.

Heparin has been used extensively as an antithrombotic and anticoagulant for close to 100 years. This anticoagulant activity is attributed mainly to the pentasaccharide sequence, which potentiates the inhibitory action of antithrombin, a major inhibitor of the coagulation cascade. More recently it has been elucidated that heparin exhibits anti-inflammatory effect via interference of the formation of neutrophil extracellular traps and this may also contribute to heparin's antithrombotic activity. This illustrates that heparin interacts with a broad range of biomolecules, exerting both anticoagulant and nonanticoagulant actions. Since our previous review, there has been an increased interest in these nonanticoagulant effects of heparin, with the beneficial role in patients infected with SARS2-coronavirus a highly topical example. This article provides an update on our previous review with more recent developments and observations made for these novel uses of heparin and an overview of the development status of heparin-based drugs. SIGNIFICANCE STATEMENT: This state-of-the-art review covers recent developments in the use of heparin and heparin-like materials as anticoagulant, now including immunothrombosis observations, and as nonanticoagulant including a role in the treatment of SARS-coronavirus and inflammatory conditions.

Comparison of the prophylactic antithrombotic effect of indobufen and warfarin in patients with nephrotic syndrome: a randomized controlled trial.

PURPOSE: The risk of thromboembolic events is elevated in patients with nephrotic syndrome, and warfarin use has been associated with an increased risk of bleeding. Indobufen, a selective cyclooxygenase-1 inhibitor, is currently being evaluated for the prevention of thromboembolic events in nephrotic syndrome. This study aimed to compare the efficacy and safety of indobufen with that of warfarin in patients with nephrotic syndrome. MATERIALS AND METHODS: This multicenter, randomized, three-arm, open-label, parallel controlled trial involved a total of 180 adult patients with nephrotic syndrome from four centers in China. Patients were randomly assigned to receive 100 mg indobufen (bid), 200 mg indobufen (bid), and 3 mg warfarin (qd) daily for 12 weeks. The primary endpoints included thromboembolic and bleeding events, while laboratory results and adverse events constituted secondary endpoints. RESULTS: No thromboembolic events occurred in the high-/low-dose indobufen and warfarin groups. Moreover, the use of a low dose of indobufen significantly reduced the risk of minor bleeding events compared with warfarin use (2% versus 18%, p < .05). Finally, adverse events were more frequent in warfarin-treated patients. CONCLUSIONS: This study found that indobufen therapy provided equivalent effects in preventing thromboembolic events compared with warfarin therapy, while low dose of indobufen was associated with a reduced risk of bleeding events, thus it should be recommended for the prevention of thromboembolic events in clinical practice in patients with nephrotic syndrome. TRIAL REGISTRATION NUMBER: ChiCTR-IPR-17013428.

Early arrival did not ensure the early acquisition of intravenous thrombosis for acute ischemic stroke during the COVID-19 pandemic.

BACKGROUND: Intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) is a time-dependent treatment with a narrow therapeutic time window, in which the time delay could result from the deadline effect. METHODS: One hospital-based cohort was recruited to detect the factors contributing to the deadline effect, where patients with the deadline effect were defined as those who were presented with the onset-to-door time (ODT) in the first 50%, while the door-to-needle time (DNT) was in the last quartile. DNT (in-hospital delay) was further subdivided into several time intervals [door-to-examination time (DET), door-to-imaging time (DIT), door-to-laboratory time (DLT), and decision-making time (DMT) of the patients or their proxies. RESULTS: A total of 186 IVT cases were enrolled, of which 17.2% (32/186) suffered a delay of the deadline effect. The median age was 66 years, and 35.5% were female. Baseline characteristics were similar between the two groups (all p > .05). For the comparisons of the time intervals, DIT (26 versus 15 min, p = .001) was significantly longer in the group with deadline effect, while the differences of DET, DLT, DMT, and ONT did not reach statistical significance (all p > .05). Upon multivariable adjustment in the binary logistic regression model, longer DIT [odds ratio (OR), 1.076; 95% confidence interval (CI), 1.036-1.118; p < .001], and history of coronary heart disease (OR, 3.898; 95%CI, 1.415-10.735; p = .008) were independently associated with deadline effect in the binary logistic regression model, while admitted in the working day (OR, 0.674; 95%CI, 0.096-0.907; p = .033), and having medical insurance (OR, 0.350; 95% CI, 0.132-0.931; p = .035) were negatively associated with the deadline effect. CONCLUSIONS: A speed-safety tradeoff phenomenon from the deadline effect was observed in 17.2% of IVT cases during the COVID-19 pandemic, where longer DIT contributed a lot to this time delay. Patients without medical insurance, or admitted in official holidays were more likely to experience a delay of the deadline effect.

Rivaroxaban in Outpatients with Mild or Moderate COVID-19: Rationale and Design of the Study CARE (CARE - Coalition COVID-19 Brazil VIII). / Rivaroxabana em Pacientes Ambulatoriais com COVID-19 Leve ou Moderada: Fundamentação e Desenho do Estudo CARE (CARE ­ Coalition COVID-19 Brazil VIII).

BACKGROUND: Previous studies have demonstrated a high risk of arterial and venous thromboembolic events as a consequence of direct viral damage to endothelial cells by SARS-CoV-2 and a procoagulant milieu due to increased biomarkers, such as D-dimer, fibrinogen, and factor VIII. Although randomized controlled trials of antithrombotic therapies have been conducted in hospitalized patients, few have evaluated the role of thromboprophylaxis in an outpatient setting. OBJECTIVE: To assess whether antithrombotic prophylaxis with rivaroxaban reduces the risk of venous or arterial thrombotic events, invasive ventilatory support, and death in COVID-19 outpatients. METHODS: The COVID Antithrombotic Rivaroxaban Evaluation (CARE) study, a multicenter, randomized, open-label, controlled trial of rivaroxaban 10 mg once daily for 14 days or local standard treatment alone to prevent adverse outcomes, is registered in clinicaltrials.gov (NCT04757857). The inclusion criteria are adults with confirmed or suspected SARS-CoV-2 infection and mild or moderate symptoms without indication for hospitalization, within 7 days of symptom onset, and 1 risk factor for COVID-19 complication (> 65 years, hypertension, diabetes mellitus, asthma, chronic obstructive pulmonary disease or other chronic lung diseases, smoking, immunosuppression, or obesity). The primary composite endpoint, which includes venous thromboembolism, invasive mechanical ventilation, major acute cardiovascular events, and mortality within 30 days of randomization, will be assessed according to the intention-to-treat principle. All patients will provide informed consent. A significance level of 5% will be used for all statistical tests. RESULTS: Major thrombotic and bleeding outcomes, hospitalizations, and deaths will be centrally adjudicated by an independent clinical events committee blinded to the assigned treatment groups. CONCLUSION: The CARE study will provide relevant and contemporary information about the potential role of thromboprophylaxis in outpatients with COVID-19.

FUNDAMENTO: Estudos anteriores revelaram alto risco de eventos tromboembólicos arteriais e venosos como consequência de danos virais diretos do SARS-CoV-2 em células endoteliais e um meio procoagulante devido ao aumento de biomarcadores como o D-dímero, fibrinogênio, fator VIII. Foram realizados ensaios controlados randomizados de terapias antitrombóticas em pacientes internados, no entanto, poucos estudos avaliaram o papel da tromboprofilaxia no ambiente ambulatorial. OBJETIVO: Avaliar se a profilaxia antitrombótica com rivaroxabana reduz o risco de eventos trombóticos venosos ou arteriais, suporte ventilatório invasivo e morte em pacientes ambulatoriais com COVID-19. MÉTODOS: O estudo CARE é um ensaio randomizado, aberto, multicêntrico e controlado por rivaroxabana 10 mg uma vez por dia durante 14 dias ou tratamento local padrão isolado, para a prevenção de resultados adversos, registrado no Clinicaltrials.gov (NCT04757857). Os critérios de inclusão são adultos com infecção confirmada ou suspeita do SARS-CoV-2, com sintomas leves ou moderados, sem indicação de hospitalização, no prazo de 7 dias após o início dos sintomas e um fator de risco de complicação da COVID-19 (>65 anos, hipertensão, diabetes, asma, doença pulmonar obstrutiva crônica ou outras doenças pulmonares crônicas, tabagismo, imunossupressão ou obesidade). O desfecho primário composto inclui tromboembolismo venoso, necessidade de ventilação mecânica invasiva, eventos cardiovasculares agudos maiores e mortalidade no prazo de 30 dias após a randomização, sendo avaliado segundo o princípio da intenção de tratar. Todos os pacientes assinaram termo de consentimento. Foi estabelecido um nível de significância de 5% para todos os testes estatísticos. RESULTADOS: Os principais desfechos trombóticos e hemorrágicos, hospitalizações e mortes serão avaliados centralmente por um comitê de eventos clínicos independente, sob a condição cega para a alocação dos grupos de tratamento. CONCLUSÃO: O estudo CARE fornecerá informação relevante e contemporânea sobre o possível papel da tromboprofilaxia em pacientes ambulatoriais com COVID-19.

Evaluation of antithrombotic prophylaxis and thrombotic events in children with COVID-19 or MIS-C: A tertiary pediatric center experience.

OBJECTIVES: COVID-19 and multisystem inflammatory syndrome in children (MIS-C) are associated with a risk of hypercoagulability and thrombotic events. We aimed (a) to evaluate the demographic, clinical, and laboratory findings as well as the incidence of thrombotic events of COVID-19 and MIS-C in children and (b) to determine the role of antithrombotic prophylaxis. METHODS: A single-center retrospective study evaluated hospitalized children with COVID-19 or MIS-C. RESULTS: The study group consisted of 690 patients, 596 (86.4%) diagnosed with COVID-19 and 94 (13.6%) diagnosed with MIS-C. Antithrombotic prophylaxis was used for 154 (22.3%) patients: 63 patients (10.6%) in the COVID-19 group and 91 (96.8%) patients in the MIS-C group. Use of antithrombotic prophylaxis was statistically higher in the MIS-C group (p<0.001). Patients who received antithrombotic prophylaxis were of older median age, were more commonly male, and had more frequent underlying diseases than those without prophylaxis (p<0.001, p<0.012, p<0.019, respectively). The most common underlying condition was obesity in patients who received antithrombotic prophylaxis. Thrombosis was observed in one (0.2%) patient in the COVID-19 group with a thrombus in the cephalic vein, two (2.1%) patients in the MIS-C group, with a dural thrombus in one patient and a cardiac thrombus in the other patient. The patients with thrombotic events were previously healthy and had mild disease. CONCLUSION: In our study, thrombotic events were rare compared with previous reports. We used antithrombotic prophylaxis for most children with underlying risk factors; perhaps for this reason, we did not observe thrombotic events in children with underlying risk factors. We suggest that patients diagnosed with COVID-19 or MIS-C be closely monitored for thrombotic events.

ISTH guidelines for antithrombotic treatment in COVID-19.

Antithrombotic agents reduce risk of thromboembolism in severely ill patients. Patients with coronavirus disease 2019 (COVID-19) may realize additional benefits from heparins. Optimal dosing and timing of these treatments and benefits of other antithrombotic agents remain unclear. In October 2021, ISTH assembled an international panel of content experts, patient representatives, and a methodologist to develop recommendations on anticoagulants and antiplatelet agents for patients with COVID-19 in different clinical settings. We used the American College of Cardiology Foundation/American Heart Association methodology to assess level of evidence (LOE) and class of recommendation (COR). Only recommendations with LOE A or B were included. Panelists agreed on 12 recommendations: three for non-hospitalized, five for non-critically ill hospitalized, three for critically ill hospitalized, and one for post-discharge patients. Two recommendations were based on high-quality evidence, the remainder on moderate-quality evidence. Among non-critically ill patients hospitalized for COVID-19, the panel gave a strong recommendation (a) for use of prophylactic dose of low molecular weight heparin or unfractionated heparin (LMWH/UFH) (COR 1); (b) for select patients in this group, use of therapeutic dose LMWH/UFH in preference to prophylactic dose (COR 1); but (c) against the addition of an antiplatelet agent (COR 3). Weak recommendations favored (a) sulodexide in non-hospitalized patients, (b) adding an antiplatelet agent to prophylactic LMWH/UFH in select critically ill, and (c) prophylactic rivaroxaban for select patients after discharge (all COR 2b). Recommendations in this guideline are based on high-/moderate-quality evidence available through March 2022. Focused updates will incorporate future evidence supporting changes to these recommendations.