Switch from oral anticoagulants to parenteral heparin in SARS-CoV-2 hospitalized patients

The 2023 Belgian clinical guidance on anticoagulation management in hospitalized and ambulatory COVID-19 patients

COVID-19 is associated with an increased risk for thrombotic complications. The trials investigating the optimal thromboprophylactic dose are performed in challenging times and seemingly produce conflicting evidence. The burdensome circumstances, divergent endpoints, and different analytical approaches hamper comparison and extrapolation of available evidence. Most importantly, clinicians should provide thromboprophylaxis in hospitalized COVID-19 patients while (re)assessing bleeding and thrombotic risk frequently. The COVID-19 Thromboprophylaxis Working Group of the BSTH updated its guidance document. It aims to summarize the available evidence critically and to guide clinicians in providing the best possible thromboprophylaxis.

Contemporary outcomes of long-term anticoagulation in COVID-19 patients: a regression matched sensitivity analysis of the national inpatient sample

BACKGROUND

The role of oral anticoagulation during the COVID-19 pandemic has been debated widely. We studied the clinical outcomes of COVID-19 hospitalizations in patients who were on long-term anticoagulation.

RESEARCH DESIGN AND METHODS

The Nationwide Inpatient Sample (NIS) database from 2020 was queried to identify COVID-19 patients with and without long-term anticoagulation. Multivariate regression analysis was used to calculate the adjusted odds ratio (aOR) of in-hospital outcomes.

RESULTS

Of 1,060,925 primary COVID-19 hospitalizations, 102,560 (9.6%) were on long-term anticoagulation. On adjusted analysis, COVID-19 patients on anticoagulation had significantly lower odds of in-hospital mortality (aOR 0.61, 95% CI 0.58-0.64, P < 0.001), acute myocardial infarction (aOR 0.72, 95% CI 0.63-0.83, P < 0.001), stroke (aOR 0.79, 95% CI 0.66-0.95, P < 0.013), ICU admissions, (aOR 0.53, 95% CI 0.49-0.57, P < 0.001) and higher odds of acute pulmonary embolism (aOR 1.47, 95% CI 1.34-1.61, P < 0.001), acute deep vein thrombosis (aOR 1.17, 95% CI 1.05-1.31, P = 0.005) compared to COVID-19 patients who were not on anticoagulation.

CONCLUSIONS

Compared to COVID-19 patients not on long-term anticoagulation, we observed lower in-hospital mortality, stroke and acute myocardial infarction in COVID-19 patients on long-term anticoagulation. Prospective studies are needed for optimal anticoagulation strategies in hospitalized patients.

Impact of atrial fibrillation and anticoagulation on the risk of death, thromboembolic disease and bleeding in patients with COVID-19: the ACO-VID Registry

OBJECTIVE

To describe the clinical profile, risk of complications and impact of anticoagulation in COVID-19 hospitalized patients, according to the presence of atrial fibrillation (AF).

METHODS

Multicenter, retrospective, and observational study that consecutively included patients >55 years admitted with COVID-19 from March to October 2020. In AF patients, anticoagulation was chosen based on clinicians' judgment. Patients were followed-up for 90 days.

RESULTS

A total of 646 patients were included, of whom 75.2% had AF. Overall, mean age was 75 ± 9.1 years and 62.4% were male. Patients with AF were older and had more comorbidities. The most common anticoagulants used during hospitalization in patients with AF were edoxaban (47.9%), low molecular weight heparin (27.0%), and dabigatran (11.7%) and among patients without AF, these numbers were 0%, 93.8% and 0%. Overall, during the study period (68 ± 3 days), 15.2% of patients died, 8.2% of patients presented a major bleeding and 0.9% had a stroke/systemic embolism. During hospitalization, patients with AF had a higher risk of major bleeding (11.3% vs 0.7%; p < .01), COVID-19-related deaths (18.0% vs 4.5%; p = .02), and all-cause deaths (20.6% vs 5.6%; p = .02). Age (HR 1.5; 95% CI 1.0-2.3) and elevated transaminases (HR 3.5; 95% CI 2.0-6.1) were independently associated with all-cause mortality. AF was independently associated with major bleeding (HR 2.2; 95% CI 1.1-5.3).

CONCLUSIONS

Among patients hospitalized with COVID-19, patients with AF were older, had more comorbidities and had a higher risk of major bleeding. Age and elevated transaminases during hospitalization, but not AF nor anticoagulant treatment increased the risk of all-cause death.

[Sustainable anticoagulation in COVID-19: Review of severity prediction and clinical reasoning]

OBJECTIVE

To identify the procoagulant phenomenon in SARS-CoV-2 patients and propose sustainable therapeutic guidance for low-income countries.

METHODS

A systematic review was conducted. It identified 5 observational studies from a scrutiny from 78 results. 712 patients were examined and the results were grouped according to mortality and severity. The comparison of the groups was interpreted using descriptive statistics.

RESULTS

D-dimer values were significantly associated with greater severity and mortality. Prothrombin was associated in some observations with higher mortality, but in terms of severity it was inconclusive.

CONCLUSION

COVID-19 disease has significant procoagulant activity and its timely treatment can alter the prognosis. The explored evidence supports sustainable methods. More evidence is needed to improve management. An early systematic approach to patients with sustainable therapeutic measures tailored to the health system is recommended.

Impact of New Onset Atrial Fibrillation in Hospitalized Patients with COVID-19. Results of the "ACO-VID" Registry

OBJECTIVE

To assess the impact of new-onset atrial fibrillation (AF) on patients hospitalized with coronavirus disease 2019 (COVID-19).

METHODS

Multicenter and retrospective study that included subjects >55 years hospitalized with COVID-19 from March to October 2020 in Spanish hospitals. Patients were divided into 3 groups (no AF, new-onset AF, and preexisting AF) and followed-up to 90 days.

RESULTS

A total of 668 patients were included, of whom 162 (24.3%) had no AF, 107 (16.0%) new-onset AF and 399 (59.7%) preexisting AF. Compared to patients without AF, those patients with new-onset AF were older and had more comorbidities, but without differences with preexisting AF. During hospitalization, in the univariate analysis, compared to patients without AF, major bleeding and cardiovascular mortality were more frequent in patients with new-onset AF (10.3% vs 0.6%; P < .001; 2.8% vs 0.6%; P = .025, respectively), with a trend toward more stroke (1.9% vs 0%; P = .085). Outcomes were similar between AF groups, but the length of stay was greater in preexisting AF patients. Among patients with new-onset AF taking reduced doses of anticoagulant treatment was associated with higher risks of stroke and major bleeding.

CONCLUSIONS

In COVID-19 hospitalized patients, new-onset AF may be associated with worse outcomes, but influenced by the dose of anticoagulants.

The pharmacology of anticoagulant drug treatment options in COVID-19 patients: reviewing real-world evidence in clinical practice

INTRODUCTION

The optimal anticoagulation strategy for venous thromboembolism (VTE) prevention among COVID-19 patients, hospitalized or in the community setting, is still challenging and largely based on real-world evidence.

AREAS COVERED

We analyzed real-world data regarding the safety and effectiveness of anticoagulant treatment, both parenteral and oral, for VTE prevention or atrial fibrillation (AF)/VTE treatment among COVID-19 patients.

EXPERT OPINION

The efficacy of low-molecular-weight heparin (LMWH) doses for VTE prevention correlates with COVID-19 disease status. LMWH prophylactic dose may be useful in COVID-19 patients at the early stage of the disease. LMWH intermediate or therapeutic dose is recommended in COVID-19 patients with an advanced stage of the disease. COVID-19 patients on VKAs therapy for atrial fibrillation (AF) and VTE should switch to NOACs in the community setting or LMWH in the hospital setting. No definitive data on de-novo starting of NOACs or VKAs therapy for VTE prevention in COVID-19 outpatients are available. In patients at high risk discharged after hospitalization due to COVID-19, thromboprophylaxis with NOACs may be considered.

The role of platelets, neutrophils and endothelium in COVID-19 infection

INTRODUCTION

COVID-19 is associated to an increased risk of thrombosis, as a result of a complex process that involves the activation of vascular and circulating cells, the release of soluble inflammatory and thrombotic mediators and blood clotting activation.

AREAS COVERED

This article reviews the pathophysiological role of platelets, neutrophils and the endothelium, and of their interactions, in the thrombotic complications of COVID-19 patients, and the current and future therapeutic approaches targeting these cell types.

EXPERT OPINION

Virus-induced platelet, neutrophil and endothelial cell changes are crucial triggers of the thrombotic complications and of the adverse evolution of COVID-19. Both the direct interaction with the virus and the associated cytokine storm concur to trigger cell activation in a classical thromboinflammatory vicious circle. Although heparin has proven to be an effective prophylactic and therapeutic weapon for the prevention and treatment of COVID-19-associated thrombosis, it acts downstream of the cascade of events triggered by SARS-CoV-2. The identification of specific molecular targets interrupting the thromboinflammatory cascade upstream, and more specifically acting either on the interaction of SARS-CoV-2 with blood and vascular cells or on the specific signalling mechanisms associated with their COVID-19-associated activation, might theoretically offer greater protection with potentially lesser side effects.

Melatonin effect on platelets and coagulation: Implications for a prophylactic indication in COVID-19

Severe COVID-19 is associated with the dynamic changes in coagulation parameters. Coagulopathy is considered as a major extra-pulmonary risk factor for severity and mortality of COVID-19; patients with elevated levels of coagulation biomarkers have poorer in-hospital outcomes. Oxidative stress, alterations in the activity of cytochrome P450 enzymes, development of the cytokine storm and inflammation, endothelial dysfunction, angiotensin-converting enzyme 2 (ACE2) enzyme malfunction and renin–angiotensin system (RAS) imbalance are among other mechanisms suggested to be involved in the coagulopathy induced by severe acute respiratory syndrome coronavirus (SARS-CoV-2). The activity and function of coagulation factors are reported to have a circadian component. Melatonin, a multipotential neurohormone secreted by the pineal gland exclusively at night, regulates the cytokine system and the coagulation cascade in infections such as those caused by coronaviruses. Herein, we review the mechanisms and beneficial effects of melatonin against coagulopathy induced by SARS-CoV-2 infection.

Pathophysiology and Management of Hypercoagulation in Infectious Diseases

Numerous systemic infections may have hypercoagulation as one of the complications, which may range from asymptomatic presentation of elevation of biochemical markers of coagulation such as that of fibrin and thrombin generation, to a much severe, symptomatic, life-threatening, disseminated intravascular coagulation (DIC), which results in the formation of thrombi in the microvasculature of various organs. This phenomenon contributes to increase in morbidity and mortality in various infectious diseases. The current review discusses various mechanisms of hypercoagulation during infections such as tissue factor activation, endothelial cell activation, inhibition of physiological anticoagulant pathways, and fibrinolysis inhibition. The review also discusses pathophysiological changes in the coagulation system and its management in the recent pandemic of COVID-19. The article also discusses role of various parenteral and oral anticoagulants in the management of infectious diseases. The review provides clinical data on various anticoagulants used during hospitalization and extended prophylaxis for the management of venous thromboembolism in various infections.

Methodology Because this is a review of published literature and no humans or animals were involved, ethical committee approval was not required and patient consent was not required.

Assessment of the Level of Protein C in Hospitalized Iraqi Patients with COVID-19 and its Correlation with Hematological and Inflammatory Markers

BACKGROUND: COVID-19 coagulopathy manifests by elevation of certain marker of active coagulation as fibrinogen and this increment associated with increased markers of inflammations. AIM: To measure protein C (PC) level in hospitalized patients with COVID-19 and to find a possible correlation with hematological and inflammatory markers. PATIENTS AND METHODS: Seventy-five hospitalized Iraqi adult patients with COVID-19 were included in a descriptive cross-sectional research. PC, D-dimer, and erythrocyte sedimentation rate (ESR) blood samples were collected, and further information was received from patient’s records. Statistical analysis was conducted using SPSS version 23 and Microsoft Office Excel 2019. RESULTS: Mean age of 75 patients included in the study was 60.13 ± 14.65 years. Sixty-two (62.7%) of patients exhibited neutrophilia, whereas 41 had lymphopenia (54.7%). High ratio of neutrophil/lymphocyte (N/L) was seen in 66 (88.0%), eosinopenia was seen in 46 (61.3%), high lactate dehydrogenase level was seen 68 (90.7%), serum ferritin was high in 66 (88.0%), and high level of C-reactive protein was seen in 68 (90.7%), increased ESR was seen in 69 (92.0%) and high level of D-dimer was seen in 56 (74.7%), while low level of PC was seen in 12 (16.0%) patients. PC had significant negative correlation with prothrombin and partial thromboplastin time but no significant correlation with hematological and inflammatory parameters. CONCLUSION: COVID-19 coagulopathy is common in majority of patients which include significant changes in WBCs counts, inflammatory markers, PC, and D-dimer levels. Such changes may have a great impact on morbidity and mortality and thus need to be monitored throughout treatment and convalescence.

SARS-CoV-2 induced coagulopathy and potential role of anticoagulation: Scoping review of literature

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can vary on a spectrum of asymptomatic disease to rarer manifestations like hypercoagulability especially among elderly patients admitted in the intensive care unit (ICU) and those with preexisting comorbidities. The exact mechanism behind this phenomenon is still unclear, however studies have shown an association with elevated cytokines and severe inflammatory response which encompasses this disease. Hypercoagulability can be limited to the lungs, or present as systemic manifestations of arterial and venous thrombosis leading to mortal outcomes. Thus, careful evaluation of risk factors should be performed by physicians and treatment with anticoagulants should be modified accordingly. All Coronavirus Disease 2019 (COVID-19) in-patients should receive thromboprophylactic therapy, with increased dosages administered to patients with increased disease severity or those with a high risk. D-dimer levels and sepsis-induced coagulopathy (SIC) score aid in identifying high risk patients and predicting outcome. This article highlights the pathophysiology behind hypercoagulability, its clinical associations and discusses therapeutic modalities to combat this fatal consequence of SARS-CoV-2.

Patients' Plasma Activity of Heparin, low-Molecular-Weight Heparin or no Anticoagulants on Urine Based DOAC Test Strips

DOAC Dipstick determines specifically the presence and absence of direct oral anticoagulants (DOACs) from patients’ urine samples and handmade test strips performed as well as the commercial version. To compare plasma activity (chromogenic substrate assays) from plasma samples with results from urine samples (DOAC test strips) of patients treated with heparin, low-molecular weight heparin (LMWH) and without anticoagulation. Plasma anti-factor Xa (aXa) activity was determined by Coamatic chromogenic substrate assay and compared to the presence of anticoagulants in urine by DOAC test strips. Patients were treated for least 5 days and samples were taken 4 hrs after administration in comparison to no treatment with an anticoagulant (n = 42). A total of 100 patients were included treated with heparin (n = 29), LMWH nadroparin (n = 29) or no anticoagulants (n = 42). Plasma aXa levels of patients treated with heparin (2 × 7.500 IU daily subcutaneously, 12 male, age 67.4 ± 11.5 years) were 0,18 IU/ml ± 0,15 IU/ml (mean, standard deviation), with LMWH (1 × 3000 IU daily subcutaneously, 15 male, age 64.2 ± 14.1 years) 0,17 IU/ml ± 0,16 IU/l, and with no anticoagulants (28 male, age 64.2 ± 15.6 years) 0,02 IU/ml ± 0.01 IU/ml. All factor Xa and thrombin inhibitor pad results of test strips were negative. We conclude that DOAC Dipstick has a high probability of not detecting heparin and LMWH in patients on treatment as well as in urine samples of patients not treated with an anticoagulant.

Chronic Oral Anticoagulation Therapy and Prognosis of Patients Admitted to Hospital for COVID-19: Insights from the HOPE COVID-19 Registry

BACKGROUND

Most evidence regarding anticoagulation and COVID-19 refers to the hospitalization setting, but the role of oral anticoagulation (OAC) before hospital admission has not been well explored. We compared clinical outcomes and short-term prognosis between patients with and without prior OAC therapy who were hospitalized for COVID-19.

METHODS

Analysis of the whole cohort of the HOPE COVID-19 Registry which included patients discharged (deceased or alive) after hospital admission for COVID-19 in 9 countries. All-cause mortality was the primary endpoint. Study outcomes were compared after adjusting variables using propensity score matching (PSM) analyses.

RESULTS

7698 patients were suitable for the present analysis (675 (8.8%) on OAC at admission: 427 (5.6%) on VKAs and 248 (3.2%) on DOACs). After PSM, 1276 patients were analyzed (638 with OAC; 638 without OAC), without significant differences regarding the risk of thromboembolic events (OR 1.11, 95% CI 0.59-2.08). The risk of clinically relevant bleeding (OR 3.04, 95% CI 1.92-4.83), as well as the risk of mortality (HR 1.22, 95% CI 1.01-1.47; log-rank p value = 0.041), was significantly increased in previous OAC users. Amongst patients on prior OAC only, there were no differences in the risk of clinically relevant bleeding, thromboembolic events, or mortality when comparing previous VKA or DOAC users, after PSM.

CONCLUSION

Hospitalized COVID-19 patients on prior OAC therapy had a higher risk of mortality and worse clinical outcomes compared to patients without prior OAC therapy, even after adjusting for comorbidities using a PSM. There were no differences in clinical outcomes in patients previously taking VKAs or DOACs. This trial is registered with NCT04334291/EUPAS34399.

COVID-19 and Venous Thromboembolism: From Pathological Mechanisms to Clinical Management

Coronavirus disease 2019 (COVID-19), which is becoming a global pandemic, is caused by SARS-CoV-2 infection. In COVID-19, thrombotic events occur frequently, mainly venous thromboembolism (VTE), which is closely related to disease severity and clinical prognosis. Compared with historical controls, the occurrence of VTE in hospitalized and critical COVID-19 patients is incredibly high. However, the pathophysiology of thrombosis and the best strategies for thrombosis prevention in COVID-19 remain unclear, thus needing further exploration. Virchow’s triad elements have been proposed as important risk factors for thrombotic diseases. Therefore, the three factors outlined by Virchow can also be applied to the formation of venous thrombosis in the COVID-19 setting. A thorough understanding of the complex interactions in these processes is important in the search for effective treatments for COVID-19. In this work, we focus on the pathological mechanisms of VTE in COVID-19 from the aspects of endothelial dysfunction, hypercoagulability, abnormal blood flow. We also discuss the treatment of VTE as well as the ongoing clinical trials of heparin anticoagulant therapy. In addition, according to the pathophysiological mechanism of COVID-19-associated thrombosis, we extended the range of antithrombotic drugs including antiplatelet drugs, antifibrinolytic drugs, and anti-inflammatory drugs, hoping to find effective drug therapy and improve the prognosis of VTE in COVID-19 patients.

Pulmonary embolism in patients with COVID-19 pneumonia on adequate oral anticoagulation

Thrombotic complications are common in patients with severe COVID-19 pneumonia with important consequences on the diagnostic and therapeutic management. We report a consecutive series of five patients on long-term oral anticoagulation therapy who presented to our hospital for severe COVID-19 pneumonia associated with segmental acute pulmonary embolism despite adherence to therapy and with an adequate anticoagulant range at the time of the event. Four patients were receiving a direct oral anticoagulant (two with edoxaban, one with rivaroxaban and one with apixaban) and one patient a vitamin K antagonist. No significant thrombotic risk factors, active cancer, or detectable venous thromboembolism were present. In all cases, elevated d-dimer and fibrinogen levels with a parallel rise in markers of inflammation were documented. The combination of these findings seems to support the hypothesis that considers the local vascular damage determined by severe viral infection as the main trigger of thrombi detected in the lungs, rather than emboli from peripheral veins.

PICO Questions and DELPHI Methodology for the Management of Venous Thromboembolism Associated with COVID-19

Patients with coronavirus disease 2019 (COVID-19) have a higher risk of venous thromboembolic disease (VTE) than patients with other infectious or inflammatory diseases, both as macrothrombosis (pulmonar embolism and deep vein thrombosis) or microthrombosis. However, the use of anticoagulation in this scenario remains controversial. This is a project that used DELPHI methodology to answer PICO questions related to anticoagulation in patients with COVID-19. The objective was to reach a consensus among multidisciplinary VTE experts providing answers to those PICO questions. Seven PICO questions regarding patients with COVID-19 responded with a broad consensus: 1. It is recommended to avoid pharmacological thromboprophylaxis in most COVID-19 patients not requiring hospital admission; 2. In most hospitalized patients for COVID-19 who are receiving oral anticoagulants before admission, it is recommended to replace them by low molecular weight heparin (LMWH) at therapeutic doses; 3. Thromboprophylaxis with LMWH at standard doses is suggested for COVID-19 patients admitted to a conventional hospital ward; 4. Standard-doses thromboprophylaxis with LMWH is recommended for COVID-19 patients requiring admission to Intensive Care Unit; 5. It is recommended not to determine D-Dimer levels routinely in COVID-19 hospitalized patients to select those in whom VTE should be suspected, or as a part of the diagnostic algorithm to rule out or confirm a VTE event; 6. It is recommended to discontinue pharmacological thromboprophylaxis at discharge in most patients hospitalized for COVID-19; 7. It is recommended to withdraw anticoagulant treatment after 3 months in most patients with a VTE event associated with COVID-19. The combination of PICO questions and DELPHI methodology provides a consensus on different recommendations for anticoagulation management in patients with COVID-19.

Heparin and Its Derivatives: Challenges and Advances in Therapeutic Biomolecules

Heparin has been extensively studied as a safe medicine and biomolecule over the past few decades. Heparin derivatives, including low-molecular-weight heparins (LMWH) and heparin pentasaccharide, are effective anticoagulants currently used in clinical settings. They have also been studied as functional biomolecules or biomaterials for various therapeutic uses to treat diseases. Heparin, which has a similar molecular structure to heparan sulfate, can be used as a remarkable biomedicine due to its uniquely high safety and biocompatibility. In particular, it has recently drawn attention for use in drug-delivery systems, biomaterial-based tissue engineering, nanoformulations, and new drug-development systems through molecular formulas. A variety of new heparin-based biomolecules and conjugates have been developed in recent years and are currently being evaluated for use in clinical applications. This article reviews heparin derivatives recently studied in the field of drug development for the treatment of various diseases.

Vitamin K in COVID-19—Potential Anti-COVID-19 Properties of Fermented Milk Fortified with Bee Honey as a Natural Source of Vitamin K and Probiotics

Vitamin K deficiency is evident in severe and fatal COVID-19 patients. It is associated with the cytokine storm, thrombotic complications, multiple organ damage, and high mortality, suggesting a key role of vitamin K in the pathology of COVID-19. To support this view, we summarized findings reported from machine learning studies, molecular simulation, and human studies on the association between vitamin K and SARS-CoV-2. We also investigated the literature for the association between vitamin K antagonists (VKA) and the prognosis of COVID-19. In addition, we speculated that fermented milk fortified with bee honey as a natural source of vitamin K and probiotics may protect against COVID-19 and its severity. The results reported by several studies emphasize vitamin K deficiency in COVID-19 and related complications. However, the literature on the role of VKA and other oral anticoagulants in COVID-19 is controversial: some studies report reductions in (intensive care unit admission, mechanical ventilation, and mortality), others report no effect on mortality, while some studies report higher mortality among patients on chronic oral anticoagulants, including VKA. Supplementing fermented milk with honey increases milk peptides, bacterial vitamin K production, and compounds that act as potent antioxidants: phenols, sulforaphane, and metabolites of lactobacilli. Lactobacilli are probiotic bacteria that are suggested to interfere with various aspects of COVID-19 infection ranging from receptor binding to metabolic pathways involved in disease prognosis. Thus, fermented milk that contains natural honey may be a dietary manipulation capable of correcting nutritional and immune deficiencies that predispose to and aggravate COVID-19. Empirical studies are warranted to investigate the benefits of these compounds.

Catastrophic Thromboembolic Syndrome During the COVID-19 Pandemic

Since March 2020, the SARS-CoV-2 virus known to cause COVID-19 has presented in many ways and it seems to affect almost all organ systems. One of its detrimental effects is on the coagulation system. Disruption of the coagulation pathway or hypercoagulability has been reported extensively in many articles and studies. It seems there is no specific pattern or location of the coagulopathy. The coagulopathy can present as part of the respiratory disease process or as an isolated phenomenon. Many articles had reported that the thrombus can be a venous thromboembolic phenomenon such as deep venous thrombosis (DVT), portal vein thrombosis, pulmonary embolism (PE), or as arterial thrombosis, for instance, coronary artery thrombosis, cerebrovascular thromboembolic disease (i.e., stroke), or an aortic thrombus. One of the disastrous presentations is what is called “catastrophic thrombosis syndrome.” This syndrome is characterized by multiple thromboses that take place in different parts of the vascular system at different parts of the body at the same time. In many studies, D-dimer levels have been shown to predict the risk of increased thromboembolism in SARS-CoV-2. However, an appropriate anticoagulation agent, dosage, and duration are yet to be determined. We are presenting an interesting case of a female who suffered catastrophic thrombosis syndrome despite being on prophylactic anticoagulation. She presented with leg pain and was found to have extensive multiple thrombi starting from the ascending/descending aorta and extending to the distal peroneal arteries.

COVID-19-related coagulopathy: A review of pathophysiology and pharmaceutical management

December 2019 will never be forgotten in the history of medicine when an outbreak of pneumonia of unknown etiology in Wuhan, China sooner or later prompted the World Health Organization to issue a public health warning emergency. This is not the first nor will it be the last time that a member of β-coronaviruses (CoVs) is waging a full-scale war against human health. Notwithstanding the fact that pneumonia is the primary symptom of the novel coronavirus (2019nCoV; designated as SARS-CoV-2), the emergence of severe disease mainly due to the injury of nonpulmonary organs at the shadow of coagulopathy leaves no choice, in some cases, rather than a dreadful death. Multiple casual factors such as inflammation, endothelial dysfunction, platelet and complement activation, renin-angiotensin-aldosterone system derangement, and hypoxemia play a major role in the pathogenesis of coagulopathy in coronavirus disease 2019 (COVID-19) patients. Due to the undeniable role of coagulation dysfunction in the initiation of several complications, assessment of coagulation parameters and the platelet count would be beneficial in early diagnosis and also timely prediction of disease severity. Although low-molecular-weight heparin is considered as the first-line of treatment in COVID-19-associated coagulopathy, several possible therapeutic options have also been proposed for better management of the disease. In conclusion, this review would help us to gain insight into the pathogenesis, clinical manifestation, and laboratory findings associated with COVID-19 coagulopathy and would summarize management strategies to alleviate coagulopathy-related complications.

Protecting older patients with cardiovascular diseases from COVID-19 complications using current medications

PURPOSE

In the pathogenesis of severe COVID-19 complications, derangements of renin-angiotensin-aldosterone system (RAAS), vascular endothelial dysfunction leading to inflammation and coagulopathy, and arrhythmias play an important role. Therefore, it is worth considering the use of currently available drugs to protect COVID-19 patients with cardiovascular diseases.

METHODS

We review the current experience of conventional cardiovascular drugs [angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers, anticoagulants, acetosalicylic acid, antiarrhythmic drugs, statins] as well as some other drug classes (antidiabetic drugs, vitamin D and NSAIDs) frequently used by older patients with cardiovascular diseases. Data were sought from clinical databases for COVID-19 and appropriate key words. Conclusions and recommendations are based on a consensus among all authors.

RESULTS

Several cardiovascular drugs have a potential to protect patients with COVID-19, although evidence is largely based on retrospective, observational studies. Despite propensity score adjustments used in many analyses observational studies are not equivalent to randomised controlled trials (RCTs). Ongoing RCTs include treatment with antithrombotics, pulmonary vasodilators, RAAS-related drugs, and colchicine. RCTs in the acute phase of COVID-19 may not, however, recognise the benefits of long term anti-atherogenic therapies, such as statins.

CONCLUSIONS

Most current cardiovascular drugs can be safely continued during COVID-19. Some drug classes may even be protective. Age-specific data are scarce, though, and conditions which are common in older patients (frailty, comorbidities, polypharmacy) must be individually considered for each drug group.

Severe Inflammation, Acute Kidney Injury, and Drug-Drug Interaction: Triple Penalty for Prolonged Elimination of Apixaban in Patients With Coronavirus Disease 2019: A Grand Round

ABSTRACT

In this article, we present a case of apixaban elimination prolonged by 450% in a patient with coronavirus disease 2019 because of multiple conditions, including drug-drug interaction, severe inflammation, and acute kidney injury. Therapeutic drug monitoring was used to explain unusual routine coagulation assays. This grand round highlights the importance of dialog between the clinician and a therapeutic drug monitoring consultant for optimal patient care.

Thromboprophylaxis in COVID-19 - Rationale and considerations

The Corona Virus Disease-2019 (COVID-19) pandemic is associated with a very high incidence of thrombotic complications. The exact mechanisms for this excess risk for clots have not been elucidated although one of the often-quoted pathophysiological entity is immunothrombosis. Recognition of thrombotic complications early on in this pandemic led to an over-explosion of studies which looked at the benefits of anticoagulation to mitigate this risk. In this review, we examine the rationale for thromboprophylaxis in COVID-19 with particular reference to dosing and discuss what may guide the decision-making process to consider anticoagulation. In addition, we explore the rationale for thrombosis prevention measures in special populations including outpatient setting, pregnant females, children, those with high body mass index and those on extracorporeal membrane oxygenation.

Early low-molecular-weight heparin administration is associated with shorter time to SARS-CoV-2 swab negativity

BACKGROUND

Antiviral and immune-modulating properties of low-molecular-weight heparin (LMWH) against Coronaviridae have been reported by in vitro studies, but no in vivo evidence is yet available. We sought to know whether the timing of prophylactic doses of LMWH during the course of COVID-19 may affect the time to SARS-CoV-2 nasal-oropharyngeal swab negativization.

METHODS

Retrospective monocentric cross-sectional study on patients requiring sub-intensive ward admission due to first SARS-CoV-2 infection and undergoing early (EH; within 7 days from COVID-19 signs and symptoms onset) versus delayed prophylactic LMWH (DH; after 7 days). SARS-CoV-2 RNA was measured by reverse transcription real-time PCR according to scheduled time points: first swab after 2 weeks from COVID-19 onset, then at 1-week intervals until negativity.

RESULTS

Time to SARS-CoV-2 swab negativity was shorter in EH (38 patients) compared with DH (55 patients): 22 versus 37 days (P=0.004). The number of confirmative negative swabs in EH was significantly higher compared with DH at week 2 (21.1% versus 3.6%; P=0.017) and 4 (60.0% versus 19.6%; P<0.001). At univariate, EH differed from DH for several disease severity and clinical management parameters. Nevertheless, after accounting for the differences, Cox regression showed early LMWH administration (hazard ratio [HR] 2.91 [1.51, 5.63]; P=0.002) and higher lymphocytes nadir (HR 1.04 [1.01, 1.08]; P=0.020) as predictors of shorter time to swab negativity.

CONCLUSIONS

This potential antiviral and/or immune-modulating activity of LMWH needs further in vivo confirmations by randomized controlled trials.

Novel Compounds Targeting Neuropilin Receptor 1 with Potential To Interfere with SARS-CoV-2 Virus Entry

Neuropilin-1 (NRP-1) is a multifunctional transmembrane receptor for ligands that affect developmental axonal growth and angiogenesis. In addition to a role in cancer, NRP-1 is a reported entry point for several viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of coronavirus disease 2019 (COVID-19). The furin cleavage product of SARS-CoV-2 Spike protein takes advantage of the vascular endothelial growth factor A (VEGF-A) binding site on NRP-1 which accommodates a polybasic stretch ending in a C-terminal arginine. This site has long been a focus of drug discovery efforts for cancer therapeutics. We recently showed that interruption of the VEGF-A/NRP-1 signaling pathway ameliorates neuropathic pain and hypothesize that interference of this pathway by SARS-CoV-2 Spike protein interferes with pain signaling. Here, we report confirmed hits from a small molecule and natural product screen of nearly 0.5 million compounds targeting the VEGF-A binding site on NRP-1. We identified nine chemical series with lead- or drug-like physicochemical properties. Using ELISA, we demonstrate that six compounds disrupt VEGF-A-NRP-1 binding more effectively than EG00229, a known NRP-1 inhibitor. Secondary validation in cells revealed that all tested compounds inhibited VEGF-A triggered VEGFR2 phosphorylation. Further, two compounds displayed robust inhibition of a recombinant vesicular stomatitis virus protein that utilizes the SARS-CoV-2 Spike for entry and fusion. These compounds represent a first step in a renewed effort to develop small molecule inhibitors of the VEGF-A/NRP-1 signaling for the treatment of neuropathic pain and cancer with the added potential of inhibiting SARS-CoV-2 virus entry.

Performance Characteristics of DOAC Dipstick in Determining Direct Oral Anticoagulants in Urine

Testing for direct oral anticoagulants (DOACs) in patient urine may facilitate medical treatment decisions. The aim of this study was to investigate interobserver variability by 2 independent observers compared to laboratory staff in the visual interpretation of factor Xa (DXI) and thrombin inhibitors (DTI) using the DOAC Dipstick test. We also examined whether test pads reacted to other anticoagulants and abnormal urine colors. The colors of the DOAC Dipstick direct factor Xa inhibitor and thrombin inhibitor pads were interpreted with 100% accuracy (95% confidence interval 0.862 to 1.000) for urine samples from persons treated with apixaban (n = 26), rivaroxaban (n = 24), and dabigatran (n = 29) and without anticoagulant therapy (n = 29). The factor Xa and thrombin inhibitor pads did not interact with heparin, nadroparin, fondaparinux, or coumadin. One µg/mL r-Hirudin and 6 µg/mL argatroban interacted with the DTI pad; however, this is unlikely to cause clinical problems because dabigatran is unlikely to be administered together with r-Hirudin and argatroban in clinical circumstances. Abnormal urine color was reliably detected by the urine color pad, so can prevent false interpretation of the DOAC Dipstick pad colors. In conclusion, we have demonstrated that interobserver variability when interpreting the DOAC Dipstick test strip is low and that factor Xa and thrombin inhibitor pads do not react to other anticoagulants such as heparins and coumadin. R-Hirudin and argatroban can be detected by the thrombin inhibitor pad and abnormal urine colors can be detected by the urine color pad to prevent false interpretation of the results in patient urine samples.

Gene variants of coagulation related proteins that interact with SARS-CoV-2

Thrombosis is a recognized complication of Coronavirus disease of 2019 (COVID-19) and is often associated with poor prognosis. There is a well-recognized link between coagulation and inflammation, however, the extent of thrombotic events associated with COVID-19 warrants further investigation. Poly(A) Binding Protein Cytoplasmic 4 (PABPC4), Serine/Cysteine Proteinase Inhibitor Clade G Member 1 (SERPING1) and Vitamin K epOxide Reductase Complex subunit 1 (VKORC1), which are all proteins linked to coagulation, have been shown to interact with SARS proteins. We computationally examined the interaction of these with SARS-CoV-2 proteins and, in the case of VKORC1, we describe its binding to ORF7a in detail. We examined the occurrence of variants of each of these proteins across populations and interrogated their potential contribution to COVID-19 severity. Potential mechanisms, by which some of these variants may contribute to disease, are proposed. Some of these variants are prevalent in minority groups that are disproportionally affected by severe COVID-19. Therefore, we are proposing that further investigation around these variants may lead to better understanding of disease pathogenesis in minority groups and more informed therapeutic approaches.

Hematological Abnormalities in COVID-19: A Narrative Review

COVID-19 is caused by SARS-CoV-2. Although pulmonary manifestations have been identified as the major symptoms, several hematological abnormalities have also been identified. This review summarizes the reported hematological abnormalities (changes in platelet, white blood cell, and hemoglobin, and coagulation/fibrinolytic alterations), explores their patho-mechanisms, and discusses its management. Common hematological abnormalities in COVID-19 are lymphopenia, thrombocytopenia, and elevated D-dimer levels. These alterations are significantly more common/prominent in patients with severe COVID-19 disease, and thus may serve as a possible biomarker for those needing hospitalization and intensive care unit care. Close attention needs to be paid to coagulation abnormalities, and steps should be taken to prevent these occurring or to mitigate their harmful effects. The effect of COVID-19 in patients with hematological abnormalities and recognized hematological drug toxicities of therapies for COVID-19 are also outlined.

Factors associated with survival in older patients affected by COVID-19: A retrospective cohort study

Aim

Mortality is high in Coronavirus disease 2019 patients with pre-existing comorbidities and advanced age. Associated complications have added to the negative prognosis. Nevertheless, many have fully recovered, even among the most fragile. Factors associated with their survival was investigated.

Methods

Retrospective study of patients aged ≥90 years admitted for COVID-19 to the Internal Medicine wards of two hospitals in Lombardy, Italy.

Results

Among 34 patients with SARS-CoV-2 pneumonia, 33 (97.1%) had respiratory failure. Eighteen patients (52.9%) survived and 16 (47.1%) died during hospital stay. Survivors compared to deceased had a significantly longer hospitalization (19 vs. 10 days respectively; p = 0.02), a better PaO2:FiO2 ratio (241 vs. 171 respectively; p = 0.003), higher lymphocyte counts (p = 0.01) and lower serum LDH levels (p < 0.001) at admission. At multivariate analysis only higher PaO2:FiO2 was associated with survival (OR 1.06 [95%CI 1.0–1.03]; p = 0.02). Kaplan-Meier analysis showed a significant difference in event-free survival between patients treated or not with LMWH (p < 0.0001) and between those treated or not with beta-blockers (p = 0.008). Cox regression, performed in the subgroup of patients who received LMWH, did not show significant difference for sex (HR 2.7 [95% CI 0.53–14.3], p = 0.23), CCI (HR 0.7 [95% CI 0.37–1.45], p = 0.38), PaO2:FiO2 ratio (HR 0.98 [95% CI 0.97–1.0], p = 0.07), corticosteroid therapy (HR 0.99 [95% CI 0.22–4.5], p = 0.99) and beta-blocker therapy (HR 2.8 [95% CI 0.56–14,7], p = 0.21).

Conclusions

Despite higher mortality in elderly, treatment with LMWH and betablockers might be associated with better survival. Dedicated studies are required to confirm our result.

Clinical profile and prognosis in patients on oral anticoagulation before admission for COVID-19

BACKGROUND

The coronavirus disease 2019 (COVID-19) shows high morbidity and mortality, particularly in patients with concomitant cardiovascular diseases. Some of these patients are under oral anticoagulation (OAC) at admission, but to date, there are no data on the clinical profile, prognosis and risk factors of such patients during hospitalization for COVID-19.

DESIGN

Subanalysis of the international 'real-world' HOPE COVID-19 registry. All patients with prior OAC at hospital admission for COVID-19 were suitable for the study. All-cause mortality was the primary endpoint.

RESULTS

From 1002 patients included, 110 (60.9% male, median age of 81.5 [IQR 75-87] years, median Short-Form Charlson Comorbidity Index [CCI] of 1 [IQR 1-3]) were on OAC at admission, mainly for atrial fibrillation and venous thromboembolism. After propensity score matching, 67.9% of these patients died during hospitalization, which translated into a significantly higher mortality risk compared to patients without prior OAC (HR 1.53, 95% CI 1.08-2.16). After multivariate Cox regression analysis, respiratory insufficiency during hospitalization (HR 6.02, 95% CI 2.18-16.62), systemic inflammatory response syndrome (SIRS) during hospitalization (HR 2.29, 95% CI 1.34-3.91) and the Short-Form CCI (HR 1.24, 95% CI 1.03-1.49) were the main risk factors for mortality in patients on prior OAC.

CONCLUSIONS

Compared to patients without prior OAC, COVID-19 patients on OAC therapy at hospital admission showed lower survival and higher mortality risk. In these patients on OAC therapy, the prevalence of several comorbidities is high. Respiratory insufficiency and SIRS during hospitalization, as well as higher comorbidity, pointed out those anticoagulated patients with increased mortality risk.

Mejorar la prevención de la trombosis y las complicaciones cardiovasculares durante la pandemia de COVID-19

Las complicaciones cardiovasculares son frecuentes en el paciente con la enfermedad coronavírica de 2019 (COVID-19), y se asocian con una mayor mortalidad. Entre las complicaciones cardiovasculares, destacan el síndrome coronario agudo, el daño miocárdico agudo (elevación de troponinas con coronarias normales), arritmias (principalmente fibrilación auricular y arritmias ventriculares), insuficiencia cardiaca, pericarditis/derrame pericárdico y complicaciones tromboembólicas (tromboembolia arterial y venosa, trombosis microvascular, embolia pulmonar, ictus). Por lo tanto, uno de los objetivos del tratamiento del paciente con COVID-19, sobre todo en sus formas más graves, es la prevención de las complicaciones cardiovasculares y trombóticas, lo que sin duda tendría un impacto positivo en el pronóstico de estos pacientes.

Fuera de este contexto, los resultados provenientes tanto de ensayos clínicos como de estudios en la práctica clínica muestran que el rivaroxabán es eficaz y seguro en todo el espectro de la enfermedad cardiovascular (fibrilación auricular, enfermedad tromboembólica venosa y enfermedad cardiovascular ateroesclerótica), por lo que podría aportar un valor añadido en la prevención de las complicaciones trombóticas y cardiovasculares durante la pandemia de COVID-19.

Hypercoagulopathy in Severe COVID-19: Implications for Acute Care

COVID-19 was first described in late 2019 and has since developed into a pandemic affecting more than 21 million people worldwide. Of particular relevance for acute care is the occurrence of COVID-19-associated coagulopathy (CAC), which is characterised by hypercoagulability, immunothrombosis and venous thromboembolism, and contributes to hypoxia in a significant proportion of patients. This review describes diagnosis and treatment of CAC in the emergency department and in intensive care. We summarise the pathological mechanisms and common complications of CAC such as pulmonary thrombosis and venous thromboembolic events and discuss current strategies for thromboprophylaxis and therapeutic anti-coagulation in the acute care setting.

The Complex Management of Atrial Fibrillation and Cancer in the COVID-19 Era: Drug Interactions, Thromboembolic Risk, and Proarrhythmia

PURPOSE OF REVIEW

Cardiotoxicity by anticancer agents has emerged as a multifaceted issue and is expected to affect both mortality and morbidity. This review summarizes clinical challenges in the management of oncological patients requiring anticoagulants for atrial fibrillation (AF) also considering the current outbreak of the COVID-19 (coronavirus disease 2019) pandemic, since this infection can add challenges to the management of both conditions. Specifically, the aims are manyfold: (1) describe the evolving use of direct oral anticoagulants (DOACs) in AF patients with cancer; (2) critically appraise the risk of clinically important drug-drug interactions (DDIs) between DOACs and oral targeted anticancer agents; (3) address expected DDIs between DOACs and candidate anti-COVID drugs, with implications on management of the underlying thrombotic risk; and (4) characterize the proarrhythmic liability in cardio-oncology in the setting of COVID-19, focusing on QT prolongation.

RECENT FINDINGS

AF in cardio-oncology poses diagnostic and management challenges, also due to the number of anticancer drugs recently associated with AF onset/worsening. Oral targeted drugs can potentially interact with DOACs, with increased bleeding risk mainly due to pharmacokinetic DDIs. Moreover, the vast majority of oral anticancer agents cause QT prolongation with direct and indirect mechanisms, potentially resulting in the occurrence of torsade de pointes, especially in susceptible patients with COVID-19 receiving additional drugs with QT liability. Oncologists and cardiologists must be aware of the increased bleeding risk and arrhythmic susceptibility of patients with AF and cancer due to DDIs. High-risk individuals with COVID-19 should be prioritized to target preventive strategies, including optimal antithrombotic management, medication review, and stringent monitoring.

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.

Repurposing Known Drugs as Covalent and Non-covalent Inhibitors of the SARS-CoV-2 Papain-Like Protease

In the absence of an approved vaccine, developing effective severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antivirals is essential to tackle the current pandemic health crisis due to the coronavirus disease 2019 (COVID-19) spread. As any traditional drug discovery program is a time-consuming and costly process requiring more than one decade to be completed, in silico repurposing of existing drugs is the preferred way for rapidly selecting promising clinical candidates. We present a virtual screening campaign to identify covalent and non-covalent inhibitors of the SARS-CoV-2 papain-like protease (PLpro) showing potential multitarget activities (i.e., a desirable polypharmacology profile) for the COVID-19 treatment. A dataset including 688 phase III and 1,702 phase IV clinical trial drugs was downloaded from ChEMBL (version 27.1) and docked to the recently released crystal structure of PLpro in complex with a covalently bound peptide inhibitor. The obtained results were analyzed by combining protein-ligand interaction fingerprint similarities, conventional docking scores, and MM-GBSA-binding free energies and allowed the identification of some interesting candidates for further in vitro testing. To the best of our knowledge, this study represents the first attempt to repurpose drugs for a covalent inhibition of PLpro and could pave the way for new therapeutic strategies against COVID-19.

Prevalence of asymptomatic deep vein thrombosis in patients hospitalized with SARS-CoV-2 pneumonia: a cross-sectional study

The association between coronavirus disease 2019 (COVID-19) pneumonia and venous thrombotic disorders is still unclear. We assessed the association between COVID-19 infection-related pneumonia and proximal deep-vein thrombosis (DVT) in a cohort of patients admitted to our hospital during the European outbreak in the front line of Cremona, Lombardy. In a single-center cross-sectional study, all patients hospitalized for more than 5 days in Internal Medicine Department with confirmed COVID-19 pneumonia received 2-point compressive ultrasound assessment (CUS) of the leg vein system during a single day. Ninety-four percent of patients received enoxaparin as standard pharmacological prophylaxis for venous thromboembolism. The presence of DVT was defined as incompressibility of popliteal or common femoral vein. Out of 121 patients with COVID-19 pneumonia (mean age 71.8, 66.3% males) hospitalized on March 31st, 70 stayed in hospital for over 5 days and 66 of them underwent CUS of deep venous system of the legs. The presence of asymptomatic DVT was found in 9 patients (13.6%). No symptomatic DVT was found. Patients with DVT showed mean age = 75.7 years, mean D-dimer levels = 4.02 ng/ml and all of them received enoxaparin for thromboprophylaxis, except one. Computed tomography pulmonary angiogram confirmed pulmonary embolism in five patients. One every seven patients with COVID-19-related pneumonia, hospitalized for more than 5 days, had asymptomatic proximal DVT and half of them had confirmed PE despite standard pharmacological thromboprophylaxis. This observational study suggests the need of an active surveillance through CUS in patients hospitalized with acute SARS-COV-2 and underline the need of a more intense thromboprophylaxis.

Inflammation and thrombosis in patients with COVID-19: A prothrombotic and inflammatory disease caused by SARS coronavirus-2

Coronavirus disease 2019 (COVID-19) caused by “Severe Acute Respiratory Syndrome Coronavirus-2” (SARS-CoV-2) infection emerged in Wuhan, a city of China, and spread to the entire planet in early 2020. The virus enters the respiratory tract cells and other tissues via ACE2 receptors. Approximately 20% of infected subjects develop severe or critical disease. A cytokine storm leads to over inflammation and thrombotic events. The most common clinical presentation in COVID-19 is pneumonia, typically characterized by bilateral, peripheral, and patchy infiltrations in the lungs. However multi-systemic involvement including peripheral thromboembolic skin lesions, central nervous, gastrointestinal, circulatory, and urinary systems are reported. The disease has a higher mortality compared to other viral agents causing pneumonia and unfortunately, no approved specific therapy, nor vaccine has yet been discovered. Several clinical trials are ongoing with hydroxychloroquine, remdesivir, favipiravir, and low molecular weight heparins. This comprehensive review aimed to summarize coagulation abnormalities reported in COVID-19, discuss the thrombosis, and inflammation-driven background of the disease, emphasize the impact of thrombotic and inflammatory processes on the progression and prognosis of COVID-19, and to provide evidence-based therapeutic guidance, especially from antithrombotic and anti-inflammatory perspectives.

Management of Thrombotic Complications in COVID-19: An Update

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV‑2), is now a global pandemic. This virus primarily affects the respiratory tract and causes lung injury characterized by acute respiratory distress syndrome. Although the pathophysiology of COVID-19 is not yet clear, the most widely accepted mechanism is systemic inflammation. A clinically significant effect of the inflammation is coagulopathy. As a result of this effect, patients are found to have a high risk of venous thromboembolism. Studies have reported a high incidence of thrombotic complications in critically ill patients with COVID-19. In this review, we discuss the most updated evidence on the pathophysiology, diagnosis, and treatment of the coagulopathy of COVID-19. Prophylactic anticoagulation is recommended for all in-patients with COVID-19. Those with a higher risk of developing thromboembolic events or who have already developed venous thromboembolism should be treated with therapeutic anticoagulation. We also discuss post-discharge prophylaxis for high-risk patients and some newly proposed treatments for the hypercoagulability that could improve the outcomes of the affected 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.

In silico identification and validation of inhibitors of the interaction between neuropilin receptor 1 and SARS-CoV-2 Spike protein

Neuropilin-1 (NRP-1) is a multifunctional transmembrane receptor for ligands that affect developmental axonal growth and angiogenesis. In addition to a role in cancer, NRP-1 is a reported entry point for several viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of coronavirus disease 2019 (COVID-19). The furin cleavage product of SARS-CoV-2 Spike protein takes advantage of the vascular endothelial growth factor A (VEGF-A) binding site on NRP-1 which accommodates a polybasic stretch ending in a C-terminal arginine. This site has long been a focus of drug discovery efforts for cancer therapeutics. We recently showed that interruption of the VEGF-A/NRP-1 signaling pathway ameliorates neuropathic pain and hypothesize that interference of this pathway by SARS-CoV-2 spike protein interferes with pain signaling. Here, we report hits from a small molecule and natural product screen of nearly 0.5 million compounds targeting the VEGF-A binding site on NRP-1. We identified nine chemical series with lead- or drug-like physico-chemical properties. Using an ELISA, we demonstrate that six compounds disrupt VEGF-A-NRP-1 binding more effectively than EG00229, a known NRP-1 inhibitor. Secondary validation in cells revealed that almost all tested compounds inhibited VEGF-A triggered VEGFR2 phosphorylation. Two compounds displayed robust inhibition of a recombinant vesicular stomatitis virus protein that utilizes the SARS-CoV-2 Spike for entry and fusion. These compounds represent a first step in a renewed effort to develop small molecule inhibitors of the VEGF-A/NRP-1 signaling for the treatment of neuropathic pain and cancer with the added potential of inhibiting SARS-CoV-2 virus entry.

Potential impact on coagulopathy of gene variants of coagulation related proteins that interact with SARS-CoV-2

Thrombosis has been one of the complications of the Coronavirus disease of 2019 (COVID-19), often associated with poor prognosis. There is a well-recognized link between coagulation and inflammation, however, the extent of thrombotic events associated with COVID-19 warrants further investigation. Poly(A) Binding Protein Cytoplasmic 4 (PABPC4), Serine/Cysteine Proteinase Inhibitor Clade G Member 1 (SERPING1) and Vitamin K epOxide Reductase Complex subunit 1 (VKORC1), which are all proteins linked to coagulation, have been shown to interact with SARS proteins. We computationally examined the interaction of these with SARS-CoV-2 proteins and, in the case of VKORC1, we describe its binding to ORF7a in detail. We examined the occurrence of variants of each of these proteins across populations and interrogated their potential contribution to COVID-19 severity. Potential mechanisms by which some of these variants may contribute to disease are proposed. Some of these variants are prevalent in minority groups that are disproportionally affected by severe COVID-19. Therefore, we are proposing that further investigation around these variants may lead to better understanding of disease pathogenesis in minority groups and more informed therapeutic approaches.

Author summary

Increased blood clotting, especially in the lungs, is a common complication of COVID-19. Infectious diseases cause inflammation which in turn can contribute to increased blood clotting. However, the extent of clot formation that is seen in the lungs of COVID-19 patients suggests that there may be a more direct link. We identified three human proteins that are involved indirectly in the blood clotting cascade and have been shown to interact with proteins of SARS virus, which is closely related to the novel coronavirus. We examined computationally the interaction of these human proteins with the viral proteins. We looked for genetic variants of these proteins and examined how these variants are distributed across populations. We investigated whether variants of these genes could impact severity of COVID-19. Further investigation around these variants may provide clues for the pathogenesis of COVID-19 particularly in minority groups.

Dabigatran, the oral anticoagulant of choice at discharge in patients with non-valvular atrial fibrillation and COVID-19 infection: the ANIBAL protocol

Atrial fibrillation is a frequent complication among patients with severe coronavirus disease-2019 (COVID-19) infection. Both direct and indirect mechanisms through COVID-19 have been described to explain this relationship. COVID-19 infection increases the risk of developing both arterial and venous thrombotic complications through systemic coagulation activation, leading to increased mortality. Chronic oral anticoagulation is essential to reduce the thromboembolic risk among AF patients. Switching to low-molecular-weight heparin has been recommended during hospitalization for COVID-19 infection. Of note, at discharge, the prescription of direct oral anticoagulants may offer some advantages over vitamin K antagonists. However, oral anticoagulants should only be prescribed after the consideration of drug-drug interactions with antiviral therapies as well as of the risk of hepatotoxicity, which is common among individuals with severe COVID-19 pneumonia. Not all anticoagulants have the same risk of hepatotoxicity; dabigatran has shown a good efficacy and safety profile and could have a lower risk of hepatotoxicity. Furthermore, its metabolism by cytochrome P450 is absent and it has a specific reversal agent. Therefore, dabigatran may be considered as a first-line choice for oral anticoagulation at discharge after COVID-19 infection. In this review, the available information on the antithrombotic management of AF patients at discharge after COVID-19 infection is updated. In addition, a practical algorithm, considering renal and liver function, which facilitates the anticoagulation choice at discharge is presented.

Coagulation disorders in SARS-CoV-2 infection

A better understanding of the pathogenetic mechanisms triggered by SARS-CoV-2 infection may contribute to a more effective management of patients with COVID-19. Coagulation dysfunction is a key pathogenetic element of this disease as well as a challenge for practitioners. Marked inflammatory process found in severe forms of COVID-19, the complement activation, the cytokine storm, and disruption of the renin-angiotensin-aldosterone system are involved in the onset of thrombotic microangiopathy and large vessel coagulopathy. Virus-induced procoagulant activity occurs at the systemic level. Intravascular microthrombi disrupt vascularization in various tissues and organs, contributing to the occurrence of multiorgan failure and explain the higher morbidity and all-cause mortality of patients. It is estimated that almost 20% of patients with COVID-19 have significant coagulation disorders, and about a quarter of those hospitalized in intensive care units are prone to develop thrombosis events under prophylactic anticoagulant treatment. Some of patients who have been immunized after healing from the SARS-CoV-2 infection have a hypercoagulable state and are prone to develop thrombosis. Hypercoagulability is supported by thrombelastographic analysis: patients have an acceleration of the propagation phase of blood clot formation and higher clot strength. Markers of coagulation dysfunction in SARS-CoV2 are: decreased platelet count, increased INR, presence of fibrin degradation products, and especially higher plasma levels of D-dimers, which predict unfavorable outcome in these patients. Age, pre-existing diseases and associated risk factors, together with careful monitoring of clinical evolution and laboratory parameters allow the choice of the best personalized prophylactic or curative anticoagulant treatment.