Scientific and Standardization Committee communication: Clinical guidance on the diagnosis, prevention, and treatment of venous thromboembolism in hospitalized patients with COVID-19

COVID-19 and thrombosis: From bench to bedside

Coronavirus disease of 2019 (COVID-19) is the respiratory viral infection caused by the coronavirus SARS-CoV2 (Severe Acute Respiratory Syndrome Coronavirus 2). Despite being a respiratory illness, COVID-19 is found to increase the risk of venous and arterial thromboembolic events. Indeed, the link between COVID-19 and thrombosis is attracting attention from the broad scientific community. In this review we will analyze the current available knowledge of the association between COVID-19 and thrombosis. We will highlight mechanisms at both molecular and cellular levels that may explain this association. In addition, the article will review the antithrombotic properties of agents currently utilized or being studied in COVID-19 management. Finally, we will discuss current professional association guidance on prevention and treatment of thromboembolism associated with COVID-19.

Prognostic value of labs ordered on patients hospitalized with COVID-19

Background: Hospitalists at our institution have taken on most non-intensive care unit (ICU) coronavirus disease 2019 (COVID-19) care. Based on sparse research, our institution developed a protocol for ordering labs for this patient population, including routine admission labs in addition to eight COVID-19-specific daily labs. The study goal is to determine if COVID-19-specific admission labs have any prognostic value beyond that provided by routine admission labs and vitals, and costs of labs with no prognostic value.Methods: We retrospectively reviewed adult patients admitted with COVID-19 from 3/2020 to 7/2020. Outcomes were mortality, ICU stay, and length of hospitalization. Multivariable logistic and linear regression were used to determine if COVID-19-specific admission labs have any prognostic value beyond that provided by vitals and routine admission labs. COVID-19-specific labs were d-Dimer, fibrinogen, ferritin, LDH, CK, pro-BNP, troponin, and CRP. Multivariable models included all routine admission labs and vitals. COVID-19-specific admission labs were included in the multivariable models if the p-value was <0.05 in the univariable analysis.Results: 331 patients met study criteria, inpatient mortality was 13.0%, 52.4% of patients required ICU stays and the average length of hospitalization was 8.9 days. COVID-19-specific labs showed no additional prognostic value for mortality. CRP, LDH, and d-Dimer provided additional prognostic information for ICU stay. CRP≥100 mg/dL and LDH≥900 U/L were associated with increased length of hospitalization.Conclusion: Only 3 of 8 admission COVID-19-specific labs recommended by our institution's protocol had additional prognostic value beyond that provided by routine labs and vitals. The total cost of non-prognostic COVID-19-specific labs during the study period was $75,874.

Systematic review and meta-analysis of the prevalence of venous thromboembolic events in novel coronavirus disease-2019 patients

Background

Emerging clinical evidence has shown that patients with the novel coronavirus disease-2019 (COVID-19) have complications that include venous thromboembolism (VTE), consisting of deep vein thrombosis (DVT) and pulmonary embolism (PE). The prevalence of VTE in patients hospitalized with COVID-19 is unclear.

Methods

Eligible studies on COVID-19 were collected from PubMed, Web of Science, and Embase. Patient characteristics and information were extracted for three categories of patients: consecutive, ICU, and non-ICU group. All PEs and DVTs were diagnosed by computed tomographic pulmonary arteriography and duplex ultrasound examination, respectively. A subgroup analysis of testing strategies in ICU and non-ICU patients for PE and DVT was also performed.

Results

Forty clinical studies involving 7966 patients hospitalized with COVID-19 were included. Pooled VTE prevalence was 13% in consecutive patients (95% confidence interval [CI], 0.05-0.24; I² = 97%), 7% in non-ICU patients (95% CI, 0.01-0.18; I² = 93%), and 31% in ICU patients (95% CI, 0.22-0.42; I² = 91%). ICU patients had the highest prevalence of PE among the three groups (17% [95% CI, 0.12-0.23] vs 8% in consecutive patients [95% CI, 0.04-0.13], 4% in non-ICU patients [95% CI, 0.01-0.08]). ICU patients also had the highest DVT prevalence (25% [95% CI, 0.14-0.37] vs 7% in consecutive patients [95% CI, 0.03-0.14], and 7% in non-ICU [95% CI, 0.02-0.14]). The subgroup analysis showed a three-fold improvement in the PE and DVT detection rates in both ICU and non-ICU patients with COVID-19 when the screening test for VTE was applied. In the settings of screening tests for VTE, ICU patients have a significantly higher prevalence of PE (37% vs 10%; P < .0001) and DVT (40% vs 12%; P = .0065) compared with non-ICU patients.

Conclusions

VTE is common in patients hospitalized with COVID-19, especially among ICU patients. Screening tests for PE and DVT may significantly improve detection rates in both ICU and non-ICU patients with COVID-19 than tests based on clinical suspicion.

Revisiting One of the Dreaded Outcomes of the Current Pandemic: Pulmonary Embolism in COVID-19

Pulmonary embolism (PE) is a commonly encountered clinical entity in patients with coronavirus disease 2019 (COVID-19). Up to 1/3 of patients have been found to have PE in the setting of COVID-19. Given the novelty of the virus causing this pandemic, it has not been easy to address diagnostic and management issues in PE. Ongoing research and publications of the scientific literature have helped in dealing with COVID-19 lately and this applies to PE as well. In this article, we attempt to succinctly yet comprehensively discuss PE in patients with COVID-19 with a review of the prevailing literature.

COVID-19, Antiphospholipid Antibodies, and Catastrophic Antiphospholipid Syndrome: A Possible Association?

Since the 2019 novel coronavirus (COVID-19) was first detected in December 2019, research on the complications and fatality of this virus has hastened. Initially, case reports drew an association between COVID-19 and abnormal coagulation parameters. Subsequently, cross-sectional studies found a high prevalence of thrombosis among ICU and non-ICU COVID-19 patients. For that reason, certain studies tried to explain the pathogenic mechanisms of thrombosis, one of which was the emergence of anti-phospholipid antibodies (aPL). Although aPL have been found positive in very few patients, their association with thrombotic events stays debatable. Given the thrombotic manifestations of COVID-19 and the potential role of aPL, the catastrophic form of APS (CAPS) might be a major fatal phenomenon. However, to date, there has been no clear association of CAPS to COVID-19. Moreover, since infections, including viral respiratory similar to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are considered main etiologies for CAPS, it could be possible that SARS-CoV-2 can induce CAPS although no evidence is currently found. High quality studies are needed to develop a clear idea on the pathogenic role of aPL in the progression of thrombosis in COVID-19 patients, and how such patients could be fit into a thromboprophylaxis plan.

How to screen and diagnose deep venous thrombosis (DVT) in patients hospitalized for or suspected of COVID-19 infection, outside the intensive care units

INTRODUCTION

The Coronavirus disease-2019 outbreak (COVID-19) has been declared a pandemic by the World Health Organization. Studies report both a severe inflammatory syndrome and a procoagulant state in severe COVID-19 cases, with an increase of venous thromboembolism, including pulmonary embolism (PE) and deep vein thrombosis (DVT). In this context, we discuss the use of doppler ultrasonography (DUS) in the screening and diagnosis of DVT in ambulatory and hospitalized patients with, or suspected of having, COVID-19, outside the intensive care unit (ICU).

MATERIAL AND METHODS

Non-systematic review of the literature.

RESULTS

In patients hospitalized for or suspected of COVID-19 infection with the presence of either (a) DVT clinical symptoms, (b) a strong DVT clinical probability (Wells score>2) or (c) elevated D-dimer levels without DVT clinical symptoms and without PE on lung CT angio-scan, DVT should be investigated with DUS. In the presence of PE diagnosed clinically and/or radiologically, additional systematic DVT screening using DUS is not recommended during the COVID-19 pandemic. The use of 4-points compression DUS for DVT screen and diagnosis is the most appropriate method in this context.

DISCUSSION

Systematic DUS for DVT screening in asymptomatic COVID patients is not recommended unless the patient is in the ICU. This would increase the risk of unnecessarily exposing medical staff to SARS-CoV-2 and monopolizing limited resources during this period.

Guidance for the Management of Patients with Vascular Disease or Cardiovascular Risk Factors and COVID-19: Position Paper from VAS-European Independent Foundation in Angiology/Vascular Medicine

COVID-19 is also manifested with hypercoagulability, pulmonary intravascular coagulation, microangiopathy, and venous thromboembolism (VTE) or arterial thrombosis. Predisposing risk factors to severe COVID-19 are male sex, underlying cardiovascular disease, or cardiovascular risk factors including noncontrolled diabetes mellitus or arterial hypertension, obesity, and advanced age. The VAS-European Independent Foundation in Angiology/Vascular Medicine draws attention to patients with vascular disease (VD) and presents an integral strategy for the management of patients with VD or cardiovascular risk factors (VD-CVR) and COVID-19. VAS recommends (1) a COVID-19-oriented primary health care network for patients with VD-CVR for identification of patients with VD-CVR in the community and patients' education for disease symptoms, use of eHealth technology, adherence to the antithrombotic and vascular regulating treatments, and (2) close medical follow-up for efficacious control of VD progression and prompt application of physical and social distancing measures in case of new epidemic waves. For patients with VD-CVR who receive home treatment for COVID-19, VAS recommends assessment for (1) disease worsening risk and prioritized hospitalization of those at high risk and (2) VTE risk assessment and thromboprophylaxis with rivaroxaban, betrixaban, or low-molecular-weight heparin (LMWH) for those at high risk. For hospitalized patients with VD-CVR and COVID-19, VAS recommends (1) routine thromboprophylaxis with weight-adjusted intermediate doses of LMWH (unless contraindication); (2) LMWH as the drug of choice over unfractionated heparin or direct oral anticoagulants for the treatment of VTE or hypercoagulability; (3) careful evaluation of the risk for disease worsening and prompt application of targeted antiviral or convalescence treatments; (4) monitoring of D-dimer for optimization of the antithrombotic treatment; and (5) evaluation of the risk of VTE before hospital discharge using the IMPROVE-D-dimer score and prolonged post-discharge thromboprophylaxis with rivaroxaban, betrixaban, or LMWH.

Are children with SARS-CoV-2 infection at high risk for thrombosis? Viscoelastic testing and coagulation profiles in a case series of pediatric patients

The coagulopathy of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is well documented in adults, with increases in D-dimer and prothrombin time found to be strong predictors of mortality, and anticoagulation shown to decrease this mortality. Viscoelastic parameters such as elevations in maximum clot firmness (MCF) on rotational thromboelastometry (ROTEM) have correlated with a hypercoagulable state in adults with SARS-CoV-2. We report our experience in children infected with SARS-CoV-2, with noted elevations in D-dimer and MCF on ROTEM (indicating hypercoagulability). Exploration of viscoelastic testing to provide additional laboratory-based evidence for pediatric-specific risk assessment for thromboprophylaxis in SARS-CoV-2 is warranted.

Coronavirus Disease 2019-Associated Thrombosis and Coagulopathy: Review of the Pathophysiological Characteristics and Implications for Antithrombotic Management

Coronavirus disease 2019 (COVID‐19) is an infectious disease caused by severe acute respiratory syndrome coronavirus‐2, which has posed a significant threat to global health. Although the infection is frequently asymptomatic or associated with mild symptoms, in a small proportion of patients it can produce an intense inflammatory and prothrombotic state that can lead to acute respiratory distress syndrome, multiple organ failure, and death. Angiotensin‐converting enzyme 2, highly expressed in the respiratory system, has been identified as a functional receptor for severe acute respiratory syndrome coronavirus‐2. Notably, angiotensin‐converting enzyme 2 is also expressed in the cardiovascular system, and there are multiple cardiovascular implications of COVID‐19. Cardiovascular risk factors and cardiovascular disease have been associated with severe manifestations and poor prognosis in patients with COVID‐19. More important, patients with COVID‐19 may have thrombotic and coagulation abnormalities, promoting a hypercoagulable state and resulting in an increased rate of thrombotic and thromboembolic events. This review will describe the pathophysiological characteristics of the cardiovascular involvement following infection by severe acute respiratory syndrome coronavirus‐2, with a focus on thrombotic and thromboembolic manifestations and implications for antithrombotic management.

Large-vessel thrombotic stroke despite concurrent therapeutic anticoagulation in COVID-19-positive patient

The current COVID-19 pandemic caused by the novel SARS-CoV-2 virus is now recognized to be associated with a coagulopathy that can result in arterial and venous thromboses. In this report, we describe a case of large-vessel cerebrovascular thrombus in a therapeutically anticoagulated 89-year-old male admitted with COVID-19 infection. Despite clinical improvement following COVID-19 pneumonitis, symptoms of an acute left-sided total anterior circulation stroke rapidly developed 10 days after initial COVID-19 symptom onset. Computed tomography angiography imaging confirmed acute large-vessel thrombus in the terminal segment of the internal carotid artery resulting in acute right middle cerebral artery territory infarction. Thromboembolic events in the context of COVID-19 infection have recently been described in critically unwell patients. However, to the best of our knowledge, this is one of the first cases of large-vessel thrombus in a patient with COVID-19 infection receiving concurrent therapeutic anticoagulation.

Breakthrough venous thromboembolic events in five patients with COVID-19 on direct oral anticoagulants

What is known and objective

Coronavirus disease 2019 (COVID‐19) is associated with increased risk of venous thromboembolism (VTE). Guidance for VTE prophylaxis continues to evolve, including addressing direct oral anticoagulants (DOACs) continued upon hospitalization.

Case summaries

We present 5 patients hospitalized for COVID‐19 while on DOACs. Four patients had atrial fibrillation and had a previous VTE. Four patients developed acute VTE and one developed stroke‐like symptoms. Monitoring D‐dimer assisted with the detection of VTE. Three patients died, and two were discharged alive.

What is new and conclusion

Therapeutic failure with DOACs appears to be commonplace in COVID‐19. Further research is needed to determine whether there is an underlying cause to this association.

Venous Thromboembolism in Hospitalized COVID-19 Patients

BACKGROUND

Venous thromboembolism (VTE) is increasingly reported in seriously ill patients with COVID-19 infection. Incidence of VTE has been reported before and results varied widely in study cohorts.

AREA OF UNCERTAINTY

Incidence of major VTE (segmental pulmonary embolism and above and proximal deep vein thrombosis) which is a contributor to mortality and morbidity is not known. Also, data is unclear on the optimal anticoagulation regimen to prevent VTE.

DATA SOURCES

Multiple databases including PubMed were searched until May 12, 2020, to include studies reporting VTE in hospitalized COVID-19 adult patients. MOOSE guidelines were followed in selection, and 11 studies were included. We conducted a systematic review and meta-analysis to quantitatively assess the VTE burden in hospitalized COVID-19 patients and potential benefits of therapeutic dosing of anticoagulation compared with prophylaxis dosing for VTE prevention.

THERAPEUTIC ADVANCES

Many societies and experts recommend routine prophylactic anticoagulation with heparin for VTE prevention in hospitalized COVID-19 patients. In this meta-analysis, the pooled rate of major VTE was 12.5% in hospitalized patients and 17.2% in intensive care unit patients. When therapeutic anticoagulation dosing was compared with prophylactic anticoagulation, the pooled odds ratio of VTE was 0.33 (95% confidence interval 0.14-0.75; P = 0.008, I = 0%) suggesting statistical significance with therapeutic dosing of anticoagulation for primary prevention of VTE in all hospitalized patients. However, this should be interpreted with caution as the bleeding events and safety profile could not be ascertained because of lack of adequate information. We recommend applying this finding to hospitalized COVID 19 patients only after carefully weighing individual bleeding risks and benefits.

CONCLUSION

Major VTE events, especially pulmonary embolism, seem to be high in COVID-19 patients admitted to the intensive care unit. Therapeutic anticoagulation dosing seems to significantly benefit the odds of preventing any VTE when compared with prophylactic dosing in all hospitalized patients.

Antithrombotic prophylaxis in children and adolescents' patients with SARS-CoV-2 (COVID-19) infection: A practical guidance for clinicians

Severe coronavirus disease 2019 (COVID-19) is often associated with features of the hypercoagulable state which can manifest as venous thromboembolism (VTE) and/or microthrombosis. Given the high risk of VTE in critically ill COVID-19 patients, appropriate VTE prophylaxis seems to be an important part of managing these patients. Although many protocols regarding venous thromboembolism (VTE) prophylaxis or therapeutic (full-dose) anticoagulation have been conducted worldwide, primarily in hospitalised adult patients, details on paediatric patients, if included, are limited or incomplete. The current evidence suggests that anticoagulation therapy with low molecular weight heparins (LMWH) appears to be associated with better prognosis in patients with moderate to severe COVID-19 induced coagulopathies or elevated D-dimer levels. Our recommendations are intended to offer guidance for anticoagulation prophylaxis and treatment in COVID-19 children and adolescent patients and not intend to supersede the clinician’s judgment. We are also conscious that several clinical questions deserve further studies and clarifications because this area is rapidly evolving. (www.actabiomedica.it)

Anticoagulation in COVID - 19: An Update

The novel coronavirus disease, 2019 (COVID – 19) evolved as an unprecedented pandemic. The severe acute respiratory syndrome-corona virus-2 (SARS-CoV-2) infection has been associated with significantly deranged coagulation parameters and increased incidence of thrombotic events. Deranged coagulation parameters, such as D-dimers and fibrin degradation products, can indicate a poor prognosis, and their measurement will help stratify the patients according to the disease severity, need of intensive care unit admission, and prediction of the clinical course. Gaps in understanding the natural history of the disease cause difficulties in tailoring therapies and optimizing the management of patients. Lack of specific treatment further complicates this situation. While thrombotic events can cause significant morbidity and mortality in patients, a focused approach to the prevention and treatment of venous thromboembolism (VTE) can, to a great extent, decrease the disease burden caused by thrombotic diseases. Pharmacological prophylactic anticoagulants and mechanical therapies such as pneumatic compression devices can help prevent venous thromboembolism and other thrombotic events. Thrombotic events due to COVID-19, their prevention and management, are the focus of this paper, with the prospect of providing insights into this relatively unexplored area.

Registry of Arterial and Venous Thromboembolic Complications in Patients With COVID-19

Background

Cardiovascular complications, including myocardial infarction, ischemic stroke, and pulmonary embolism, represent an important source of adverse outcomes in coronavirus disease-2019 (COVID-19).

Objectives

To assess the frequency of arterial and venous thromboembolic disease, risk factors, prevention and management patterns, and outcomes in patients with COVID-19, the authors designed a multicenter, observational cohort study.

Methods

We analyzed a retrospective cohort of 1,114 patients with COVID-19 diagnosed through our Mass General Brigham integrated health network. The total cohort was analyzed by site of care: intensive care (n = 170); hospitalized nonintensive care (n = 229); and outpatient (n = 715). The primary study outcome was a composite of adjudicated major arterial or venous thromboembolism.

Results

Patients with COVID-19 were 22.3% Hispanic/Latinx and 44.2% non-White. Cardiovascular risk factors of hypertension (35.8%), hyperlipidemia (28.6%), and diabetes (18.0%) were common. Prophylactic anticoagulation was prescribed in 89.4% of patients with COVID-19 in the intensive care cohort and 84.7% of those in the hospitalized nonintensive care setting. Frequencies of major arterial or venous thromboembolism, major cardiovascular adverse events, and symptomatic venous thromboembolism were highest in the intensive care cohort (35.3%, 45.9%, and 27.0 %, respectively) followed by the hospitalized nonintensive care cohort (2.6%, 6.1%, and 2.2%, respectively) and the outpatient cohort (0% for all).

Conclusions

Major arterial or venous thromboembolism, major adverse cardiovascular events, and symptomatic venous thromboembolism occurred with high frequency in patients with COVID-19, especially in the intensive care setting, despite a high utilization rate of thromboprophylaxis.

Coagulopathy, Venous Thromboembolism, and Anticoagulation in Patients with COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has led to a worldwide pandemic, and patients with the infection are referred to as having COVID‐19. Although COVID‐19 is commonly considered a respiratory disease, there is clearly a thrombotic potential that was not expected. The pathophysiology of the disease and subsequent coagulopathy produce an inflammatory, hypercoagulable, and hypofibrinolytic state. Several observational studies have demonstrated surprisingly high rates of venous thromboembolism (VTE) in both general ward and intensive care patients with COVID‐19. Many of these observational studies demonstrate high rates of VTE despite patients being on standard, or even higher intensity, pharmacologic VTE prophylaxis. Fibrinolytic therapy has also been used in patients with acute respiratory distress syndrome. Unfortunately, high quality randomized controlled trials are lacking. A literature search was performed to provide the most up‐to‐date information on the pathophysiology, coagulopathy, risk of VTE, and prevention and treatment of VTE in patients with COVID‐19. These topics are reviewed in detail, along with practical issues of anticoagulant selection and duration. Although many international organizations have produced guidelines or consensus statements, they do not all cover the same issues regarding anticoagulant therapy for patients with COVID‐19, and they do not all agree. These statements and the most recent literature are combined into a list of clinical considerations that clinicians can use for the prevention and treatment of VTE in patients with COVID‐19.

Thrombosis and Coagulopathy in COVID-19

Since December 2019, an outbreak of coronavirus disease 2019 (COVID-19) which initially occurred in the city of Wuhan, located in China's Hubei province, spread around the world and on March 11, 2020, the World Health Organization declared the new Coronavirus disease 2019 (COVID-19) as a pandemic. The presence of comorbidities (eg, cardiovascular disease, obesity), Sepsis Induced Coagulopathy score >4, elevation of D-dimer (>6 times the normal value), C-reactive protein, troponins and other disseminated intravascular coagulation markers; is associated to a worse prognosis in hospitalized patients with severe COVD-19, reaching a hospital mortality of 42%. Initial anticoagulant treatment with low molecular weight heparin has been shown to reduce mortality by 48% at 7 days and 37% at 28 days and achieve a significant improvement in the arterial oxygen pressure/inspired fraction of O2 (PaO2/FiO2) by mitigating the formation of microthrombi and associated pulmonary coagulopathy.

Anticoagulant interventions in hospitalized patients with COVID-19: A scoping review of randomized controlled trials and call for international collaboration

INTRODUCTION

Coronavirus disease (COVID-19) is associated with a high incidence of thrombosis and mortality despite standard anticoagulant thromboprophylaxis. There is equipoise regarding the optimal dose of anticoagulant intervention in hospitalized patients with COVID-19 and consequently, immediate answers from high-quality randomized trials are needed.

METHODS

The World Health Organization's International Clinical Trials Registry Platform was searched on June 17, 2020 for randomized controlled trials comparing increased dose to standard dose anticoagulant interventions in hospitalized COVID-19 patients. Two authors independently screened the full records for eligibility and extracted data in duplicate.

RESULTS

A total of 20 trials were included in the review. All trials are open label, 5 trials use an adaptive design, 1 trial uses a factorial design, 2 trials combine multi-arm parallel group and factorial designs in flexible platform trials, and at least 15 trials have multiple study sites. With individual target sample sizes ranging from 30 to 3000 participants, the pooled sample size of all included trials is 12 568 participants. Two trials include only intensive care unit patients, and 10 trials base patient eligibility on elevated D-dimer levels. Therapeutic intensity anticoagulation is evaluated in 14 trials. All-cause mortality is part of the primary outcome in 14 trials.

DISCUSSION

Several trials evaluate different dose regimens of anticoagulant interventions in hospitalized patients with COVID-19. Because these trials compete for sites and study participants, a collaborative effort is needed to complete trials faster, conduct pooled analyses and bring effective interventions to patients more quickly.

COVID-19 and Venous Thromboembolism Pharmacologic Thromboprophylaxis

BACKGROUND

Coagulopathy has emerged as a hallmark issue of the coronavirus 2019 (COVID-19). Medical facilities are faced with the challenge of developing institutional thromboprophylaxis protocols; however, due to the novelty of the disease, there is a dearth of high-quality, prospective evidence for decision making.

OBSERVATIONS

The US National Institutes of Health along with 4 leading societies in the fields of thrombosis and hemostasis have published guidance based on expert consensus that helps provide a framework for local policy development. While there is agreement in a few areas, there are notable and sometimes considerable differences in recommendations that facilities should discuss when developing local guidance.

CONCLUSIONS

This document aims to streamline and simplify the available guidance so health care providers can readily identify consensus and divergence of COVID-19 thromboprophylaxis recommendations. Additionally, the authors provide and briefly highlight the COVID-19 thromboprophylaxis protocol of the US Department of Veterans Affairs Tennessee Valley Healthcare System in Nashville and Murfreesboro to serve as an example of a guideline-directed approach for order-set development.

COVID-19 coagulopathy in pregnancy: Critical review, preliminary recommendations, and ISTH registry-Communication from the ISTH SSC for Women's Health

BACKGROUND

Novel coronavirus (SARS-CoV-2), which causes COVID-19, has thus far affected more than 15 million individuals, resulting in more than 600 000 deaths worldwide, and the number continues to rise. In a large systematic review and meta-analysis of the literature including 2567 pregnant women, 7% required intensive care admission, with a maternal mortality ~1% and perinatal mortality below 1%. There has been a rapid increase in publications on COVID-19-associated coagulopathy, including disseminated intravascular coagulopathy and venous thromboembolism, in the non-pregnant population, but very few reports of COVID-19 coagulopathy during pregnancy; leaving us with no guidance for care of this specific population.

METHODS

This is a collaborative effort conducted by a group of experts that was reviewed, critiqued, and approved by the International Society on Thrombosis and Haemostasis Subcommittee for Women's Health Issues in Thrombosis and Hemostasis. A structured literature search was conducted, and the quality of current and emerging evidence was evaluated. Based on the published studies in the non-pregnant and pregnant population with a moderate to high risk of bias as assessed by Newcastle-Ottawa scale and acknowledging the absence of data from randomized clinical trials for management of pregnant women infected with SARS-CoV-2, a consensus in support of a guidance document for COVID-19 coagulopathy in pregnancy was identified.

RESULTS AND CONCLUSIONS

Specific hemostatic issues during pregnancy were highlighted, and preliminary recommendations to assist in the care of COVID-19-affected pregnant women with coagulopathy or thrombotic complications were developed. An international registry to gather data to support the management of COVID-19 and associated coagulopathy in pregnancy was established.

Thromboprophylaxis: balancing evidence and experience during the COVID-19 pandemic

A common and potent consideration has recently entered the landscape of the novel coronavirus disease of 2019 (COVID-19): venous thromboembolism (VTE). COVID-19 has been associated to a distinctive related coagulopathy that shows unique characteristics. The research community has risen to the challenges posed by this « evolving COVID-19 coagulopathy » and has made unprecedented efforts to promptly address its distinct characteristics. In such difficult time, both national and international societies of thrombosis and hemostasis released prompt and timely responses to guide recognition and management of COVID-19-related coagulopathy. However, latest guidelines released by the international Society on Thrombosis and Haemostasis (ISTH) on May 27, 2020, followed the American College of Chest Physicians (CHEST) on June 2, 2020 showed some discrepancies regarding thromboprophylaxis use. In this forum article, we would like to offer an updated focus on thromboprophylaxis with current incidence of VTE in ICU and non-ICU patients according to recent published studies; highlight the main differences regarding ISTH and CHEST guidelines; summarize and describe which are the key ongoing RCTs testing different anticoagulation strategies in patients with COVID-19; and finally set a proposal for COVID-19 coagulopathy specific risk factors and dedicated trials.

Venous Thromboembolism in COVID-19

The coronavirus disease 2019 (COVID-19) is our latest pandemic, preceded by the H1N1 swine flu in 2009, which lasted approximately 19 months. One of the special characteristics of COVID-19 is the propensity to cause venous thromboembolism (VTE). Thromboinflammation seems to play a prominent role in the pathogenesis. We will here review some mechanisms in the pathogenesis and discuss some hematological biomarkers, and also whether they serve as useful risk factors for VTE. The role of general risk assessment models for medically ill patients specifically in COVID-19 is appraised. The type of prophylaxis and particularly whether standard or augmented doses of chemoprophylaxis should be used is reviewed based on available evidence. We are also comparing recommendations from 10 different guidance or position/consensus statements. Treatment recommendations for patients with COVID-19 and pulmonary embolism are discussed with current general treatment guidelines as reference. Specifics for patients with COVID-19 are pointed out and the potential role of thrombolytic treatment is explored.

Venous thromboembolism in COVID-19 patients

COVID-19 is a potentially serious respiratory disease caused by the SARS-CoV-2 virus that involves an increased risk of venous thromboembolism (VTE). Its pathophysiology is apparently related to an exacerbated inflammatory process and coagulopathy, verified by an increase in D-dimer, fibrinogen, and fibrin degradation products. Occurrence must be monitored, prevented, and treated according to existing recommendations and guidelines. The increased risk of thrombosis, and the association between this phenomenon and the most severe forms of the disease and death have prompted some groups to propose a more aggressive prophylactic and therapeutic approach. However, the risk-benefit profile of this type of conduct has not been defined and cases must be assessed individually, with a multidisciplinary approach. In this study, we review the main studies and evidence available to date on diagnosis, prophylaxis, and treatment of venous thromboembolism in COVID-19 patients.

Thrombosis Management and Challenges in COVID-19 Patients Presenting with Acute Coronary Syndromes

Thrombotic complications in patients with coronavirus disease 2019 (COVID-19) infection have been increasingly recognized, particularly those affecting the cardiovascular system. Patients with COVID-19 infection can suffer from increased coagulopathy as well as myocardial injury. In this review, we discuss these complications with special focus on management challenges in patients with acute coronary disease based on the available evidence from published literature.

The Impact of COVID-19 Disease on Platelets and Coagulation

Coronavirus disease 2019 (COVID-19) causes a spectrum of disease; some patients develop a severe proinflammatory state which can be associated with a unique coagulopathy and procoagulant endothelial phenotype. Initially, COVID-19 infection produces a prominent elevation of fibrinogen and D-dimer/fibrin(ogen) degradation products. This is associated with systemic hypercoagulability and frequent venous thromboembolic events. The degree of D-dimer elevation positively correlates with mortality in COVID-19 patients. COVID-19 also leads to arterial thrombotic events (including strokes and ischemic limbs) as well as microvascular thrombotic disorders (as frequently documented at autopsy in the pulmonary vascular beds). COVID-19 patients often have mild thrombocytopenia and appear to have increased platelet consumption, together with a corresponding increase in platelet production. Disseminated intravascular coagulopathy (DIC) and severe bleeding events are uncommon in COVID-19 patients. Here, we review the current state of knowledge of COVID-19 and hemostasis.

Elevated eosinophil count is related with lower anti-factor Xa activity in COVID-19 patients

Despite prophylactic anticoagulant treatments, thrombotic complications may develop in patients with coronavirus disease 2019 (COVID-19). This study aimed to evaluate the factors influencing anti-factor Xa activity in COVID-19 patients receiving low molecular weight heparin (LMWH). We prospectively evaluated 80 COVID-19 patients, diagnosed using polymerase chain reaction test, who were admitted to our clinic and administered LMWH; LMWH (enoxaparin) was applied according to the weight, D-dimer levels, and clinical condition of patients. Anti-factor Xa activity in blood, drawn 4 h after the 3rd dose of LMWH, was measured and an activity of < 0.2 IU/mL was considered subprophylactic. Patients were followed up clinically, and anti-factor Xa activity was re-examined before discharge. Groups 1 and 2 included 13 and 67 patients with subprophylactic (mean ± SD: 0.18 ± 0.06) and prophylactic (mean ± SD: 0.43 ± 0.23) anti-factor Xa activity, respectively. The proportion of eosinophils in patients was significantly higher in group 1 than in group 2 (mean ± SD; 2.96 ± 2.55 vs 0.90 ± 1.28; p = 0.001). At the time of discharge, the eosinophilic proportion of patients was significantly higher (eosinophil %, mean ± SD; 3.06 ± 1.49 vs 2.07 ± 1.92; p = 0.001), but the activated partial thromboplastin time was significantly lower (22.34 ± 1.38 vs 24.38 ± 3.58; p = 0.01) in group 1 than in group 2. Of 14 patients with eosinophil content > 4%, 6 were in group 1 ((6/13) 46.2%), while 8 were in group 2 ((8/63) 11.9%); (p = 0.009), and all had a D-dimer level < 1 μg/mL (p = 0.03). ROC analysis for the presence of anticoagulation at subprophylactic level revealed an area under curve of 0.79 (95% CI: 0.64-0.93); p = 0.001). In conclusion; Elevated eosinophil count is related to lower anti-factor Xa activity in patients with COVID-19 receiving LMWH. The clinical significance of the subprophylactic anti-factor Xa activity should be studied in COVID-19 patients (NCT04507282).

Postdischarge venous thromboembolism following hospital admission with COVID-19

The association of severe coronavirus disease 2019 (COVID-19) with an increased risk of venous thromboembolism (VTE) has resulted in specific guidelines for its prevention and management. The VTE risk appears highest in those with critical care admission. The need for postdischarge thromboprophylaxis remains controversial, which is reflected in conflicting expert guideline recommendations. Our local protocol provides thromboprophylaxis to COVID-19 patients during admission only. We report postdischarge VTE data from an ongoing quality improvement program incorporating root-cause analysis of hospital-associated VTE (HA-VTE). Following 1877 hospital discharges associated with COVID-19, 9 episodes of HA-VTE were diagnosed within 42 days, giving a postdischarge rate of 4.8 per 1000 discharges. Over 2019, following 18 159 discharges associated with a medical admission; there were 56 episodes of HA-VTE within 42 days (3.1 per 1000 discharges). The odds ratio for postdischarge HA-VTE associated with COVID-19 compared with 2019 was 1.6 (95% confidence interval, 0.77-3.1). COVID-19 hospitalization does not appear to increase the risk of postdischarge HA-VTE compared with hospitalization with other acute medical illness. Given that the risk-benefit ratio of postdischarge thromboprophylaxis remains uncertain, randomized controlled trials to evaluate the role of continuing thromboprophylaxis in COVID-19 patients following hospital discharge are required.

Approach to the Patient with COVID-19-Associated Thrombosis: A Case-Based Review

Coronavirus disease 2019 (COVID-19) is a current global pandemic caused by the novel coronavirus SARS-CoV-2. Alongside its potential to cause severe respiratory illness, studies have reported a distinct COVID-19-associated coagulopathy that is characterized by elevated D-dimer levels, hyperfibrinogenemia, mild thrombocytopenia, and slight prolongation of the prothrombin time. Studies have also reported increased rates of thromboembolism in patients with COVID-19, but variations in study methodologies, patient populations, and anticoagulation strategies make it challenging to distill implications for clinical practice. Here, we present a practical review of current literature and uses a case-based format to discuss the diagnostic approach and management of COVID-19-associated coagulopathy. IMPLICATIONS FOR PRACTICE: Coronavirus disease 2019 (COVID-19)-associated coagulopathy is characterized by elevated D-dimer levels, hyperfibrinogenemia, and increased rates of thromboembolism. Current management guidelines are based on limited evidence from retrospective studies that should be interpreted carefully. At this time, all hospitalized patients with suspected or confirmed COVID-19 should receive coagulation test surveillance and standard doses of prophylactic anticoagulation until prospective randomized controlled trials yield definitive information in support of higher prophylactic doses.

Emerging patterns of hypercoagulability associated with critical COVID-19: A review

While the COVID-19 pandemic sweeps the world, much evidence is being gathered regarding its novel pathological mechanisms. It is the authors' clinical experience that patients in the intensive care unit suffering from COVID-19 are extremely pro-coagulable, with venous and arterial thromboembolism frequently observed, and losses of vascular access lines and filtration circuits to thrombosis now commonplace. Here, we explore the evidence for hypercoagulability in this group, presenting evidence of both a localised pulmonary hypercoagulability, and a systemic hypercoagulability resulting in thrombosis distant to the pulmonary vasculature. Furthermore, we discuss the possible risk factors exacerbated by, or selected for in COVID-19. We review the available evidence for use of plasma D-dimer as a prognostic marker, exploring the possibility that it acts as a marker of a COVID-19-associated hypercoagulability. We review the evidence for a pro-coagulant subtype of disseminated intravascular coagulation, discussing its clinical significance. Finally, we discuss the current evidence surrounding treatment of COVID-19 hypercoagulability, including prophylactic and treatment-dose heparin, thrombolytic agents, antiplatelet agents, and direct thrombin inhibitors, among others. We suggest areas in which further investigation is urgently needed to reduce the startling incidence of thrombosis in this group, a complication no doubt contributing to morbidity and mortality.

Current Overview on Hypercoagulability in COVID-19

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has brought many unique pathologies, such as coagulopathy, prompting a desperate need for effective management. COVID-19-associated coagulopathy (CAC) can cause various thromboembolic complications, especially in critically ill patients. The pathogenesis is likely due to endothelial injury, immobilization, and an increase in circulating prothrombotic factors. Data on treatment are limited, although prophylactic anticoagulation is advised in all hospitalized patients. Herein, we have comprehensively reviewed the current literature available on CAC and highlight the pathogenesis, clinical features, and management of CAC.

Risk of venous thromboembolism in patients with COVID-19: A systematic review and meta-analysis

BACKGROUND

Venous thromboembolism (VTE) is frequently observed in patients with coronavirus disease 2019 (COVID-19). However, reported VTE rates differ substantially.

OBJECTIVES

We aimed at evaluating available data and estimating the prevalence of VTE in patients with COVID-19.

METHODS

We conducted a systematic literature search (MEDLINE, EMBASE, World Health Organization COVID-19 database) to identify studies reporting VTE rates in patients with COVID-19. Studies with suspected high risk of bias were excluded from quantitative synthesis. Pooled outcome rates were obtained within a random effects meta-analysis. Subgroup analyses were performed for different settings (intensive care unit [ICU] vs non-ICU hospitalization and screening vs no screening) and the association of d-dimer levels and VTE risk was explored.

RESULTS

Eighty-six studies (33,970 patients) were identified and 66 (28,173 patients, mean age: 62.6 years, 60.1% men, 19.4% ICU patients) were included in quantitative analysis. The overall VTE prevalence estimate was 14.1% (95% confidence interval [CI], 11.6-16.9), 40.3% (95% CI, 27.0-54.3) with ultrasound screening and 9.5% (95% CI, 7.5-11.7) without screening. Subgroup analysis revealed high heterogeneity, with a VTE prevalence of 7.9% (95% CI, 5.1-11.2) in non-ICU and 22.7% (95% CI, 18.1-27.6) in ICU patients. Prevalence of pulmonary embolism (PE) in non-ICU and ICU patients was 3.5% (95% CI, 2.2-5.1) and 13.7% (95% CI, 10.0-17.9). Patients developing VTE had higher d-dimer levels (weighted mean difference, 3.26 µg/mL; 95% CI, 2.76-3.77) than non-VTE patients.

CONCLUSION

VTE occurs in 22.7% of patients with COVID-19 in the ICU, but VTE risk is also increased in non-ICU hospitalized patients. Patients developing VTE had higher d-dimer levels. Studies evaluating thromboprophylaxis strategies in patients with COVID-19 are needed to improve prevention of VTE.

Risk of venous thromboembolism in patients with COVID-19: A systematic review and meta-analysis

Background

Venous thromboembolism (VTE) is frequently observed in patients with coronavirus disease 2019 (COVID-19). However, reported VTE rates differ substantially.

Objectives

We aimed at evaluating available data and estimating the prevalence of VTE in patients with COVID-19.

Methods

We conducted a systematic literature search (MEDLINE, EMBASE, World Health Organization COVID-19 database) to identify studies reporting VTE rates in patients with COVID-19. Studies with suspected high risk of bias were excluded from quantitative synthesis. Pooled outcome rates were obtained within a random effects meta-analysis. Subgroup analyses were performed for different settings (intensive care unit [ICU] vs non-ICU hospitalization and screening vs no screening) and the association of d-dimer levels and VTE risk was explored.

Results

Eighty-six studies (33,970 patients) were identified and 66 (28,173 patients, mean age: 62.6 years, 60.1% men, 19.4% ICU patients) were included in quantitative analysis. The overall VTE prevalence estimate was 14.1% (95% confidence interval [CI], 11.6-16.9), 40.3% (95% CI, 27.0-54.3) with ultrasound screening and 9.5% (95% CI, 7.5-11.7) without screening. Subgroup analysis revealed high heterogeneity, with a VTE prevalence of 7.9% (95% CI, 5.1-11.2) in non-ICU and 22.7% (95% CI, 18.1-27.6) in ICU patients. Prevalence of pulmonary embolism (PE) in non-ICU and ICU patients was 3.5% (95% CI, 2.2-5.1) and 13.7% (95% CI, 10.0-17.9). Patients developing VTE had higher d-dimer levels (weighted mean difference, 3.26 µg/mL; 95% CI, 2.76-3.77) than non-VTE patients.

Conclusion

VTE occurs in 22.7% of patients with COVID-19 in the ICU, but VTE risk is also increased in non-ICU hospitalized patients. Patients developing VTE had higher d-dimer levels. Studies evaluating thromboprophylaxis strategies in patients with COVID-19 are needed to improve prevention of VTE.

Neutrophil extracellular traps infiltrate the lung airway, interstitial, and vascular compartments in severe COVID-19

Infection with SARS-CoV-2 is causing a deadly and pandemic disease called coronavirus disease-19 (COVID-19). While SARS-CoV-2-triggered hyperinflammatory tissue-damaging and immunothrombotic responses are thought to be major causes of respiratory failure and death, how they relate to lung immunopathological changes remains unclear. Neutrophil extracellular traps (NETs) can contribute to inflammation-associated lung damage, thrombosis, and fibrosis. However, whether NETs infiltrate particular compartments in severe COVID-19 lungs remains to be clarified. Here we analyzed postmortem lung specimens from four patients who succumbed to COVID-19 and four patients who died from a COVID-19-unrelated cause. We report the presence of NETs in the lungs of each COVID-19 patient. NETs were found in the airway compartment and neutrophil-rich inflammatory areas of the interstitium, while NET-prone primed neutrophils were present in arteriolar microthrombi. Our results support the hypothesis that NETs may represent drivers of severe pulmonary complications of COVID-19 and suggest that NET-targeting approaches could be considered for the treatment of uncontrolled tissue-damaging and thrombotic responses in COVID-19.

Thrombosis and COVID-19: The Potential Role of Nutrition

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for the coronavirus disease (COVID-19), is a contagion that has rapidly spread around the globe. COVID-19 has caused significant loss of life and disrupted global society at a level never before encountered. While the disease was predominantly characterized by respiratory symptoms initially, it became clear that other systems including the cardiovascular and neurological systems were also involved. Several thrombotic complications were reported including venous thrombosis, vasculitis, cardiomyopathy, and stroke. Thrombosis and inflammation are implicated in various non-communicable diseases (NCDs). This is of significant concern as people with pre-existing conditions such as cardiovascular disorders, renal disorders, obesity, metabolic syndrome, and diabetes are at greater risk of severe COVID-19 infection. Consequently, the research surrounding the use of anticoagulants, antiplatelet, and antithrombotic strategies for prophylaxis and treatment of COVID-19 is of critical importance. The adoption of a healthy diet, physical exercise, and lifestyle choices can reduce the risk factors associated with NCDs and the thrombo-inflammatory complications. In this review, these thrombotic complications and potential foods, nutraceuticals, and the antithrombotic constituents within that may prevent the onset of severe thrombotic complications as a result of infection are discussed. While nutrition is not a panacea to tackle COVID-19, it is apparent that a patient's nutritional status may affect patient outcomes. Further intensive research is warranted to reduce to incidence of thrombotic complications.

Intermediate versus standard-dose prophylactic anticoagulation and statin therapy versus placebo in critically-ill patients with COVID-19: Rationale and design of the INSPIRATION/INSPIRATION-S studies

BACKGROUND

Microvascular and macrovascular thrombotic events are among the hallmarks of coronavirus disease 2019 (COVID-19). Furthermore, the exuberant immune response is considered an important driver of pulmonary and extrapulmonary manifestations of COVID-19. The optimal management strategy to prevent thrombosis in critically-ill patients with COVID-19 remains unknown.

METHODS

The Intermediate versus Standard-dose Prophylactic anticoagulation In cRitically-ill pATIents with COVID-19: An opeN label randomized controlled trial (INSPIRATION) and INSPIRATION-statin (INSPIRATION-S) studies test two independent hypotheses within a randomized controlled trial with 2 × 2 factorial design. Hospitalized critically-ill patients with reverse transcription polymerase chain reaction confirmed COVID-19 will be randomized to intermediate-dose versus standard dose prophylactic anticoagulation. The 600 patients undergoing this randomization will be screened and if meeting the eligibility criteria, will undergo an additional double-blind stratified randomization to atorvastatin 20 mg daily versus matching placebo. The primary endpoint, for both hypotheses will be tested for superiority and includes a composite of adjudicated acute arterial thrombosis, venous thromboembolism (VTE), use of extracorporeal membrane oxygenation, or all-cause death within 30 days from enrollment. Key secondary endpoints include all-cause mortality, adjudicated VTE, and ventilator-free days. Key safety endpoints include major bleeding according to the Bleeding Academic Research Consortium definition and severe thrombocytopenia (platelet count <20,000/fL) for the anticoagulation hypothesis. In a prespecified secondary analysis for non-inferiority, the study will test for the non-inferiority of intermediate intensity versus standard dose anticoagulation for major bleeding, considering a non-inferiority margin of 1.8 based on odds ratio. Key safety endpoints for the statin hypothesis include rise in liver enzymes >3 times upper normal limit and clinically-diagnosed myopathy. The primary analyses will be performed in the modified intention-to-treat population. Results will be tested in exploratory analyses across key subgroups and in the intention-to-treat and per-protocol cohorts.

CONCLUSIONS

INSPIRATION and INSPIRATON-S studies will help address clinically-relevant questions for antithrombotic therapy and thromboinflammatory therapy in critically-ill patients with COVID-19.