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

Dysregulated thrombospondin 1 and miRNA-29a-3p in severe COVID-19

Although nearly a fifth of symptomatic COVID-19 patients suffers from severe pulmonary inflammation, the mechanism of developing severe illness is not yet fully understood. To identify significantly altered genes in severe COVID-19, we generated messenger RNA and micro-RNA profiling data of peripheral blood mononuclear cells (PBMCs) from five COVID-19 patients (2 severe and 3 mild patients) and three healthy controls (HC). For further evaluation, two publicly available RNA-Seq datasets (GSE157103 and GSE152418) and one single-cell RNA-Seq dataset (GSE174072) were employed. Based on RNA-Seq datasets, thrombospondin 1 (THBS1) and interleukin-17 receptor A (IL17RA) were significantly upregulated in severe COVID-19 patients' blood. From single-cell RNA-sequencing data, IL17RA level is increased in monocytes and neutrophils, whereas THBS1 level is mainly increased in the platelets. Moreover, we identified three differentially expressed microRNAs in severe COVID-19 using micro-RNA sequencings. Intriguingly, hsa-miR-29a-3p significantly downregulated in severe COVID-19 was predicted to bind the 3'-untranslated regions of both IL17RA and THBS1 mRNAs. Further validation analysis of our cohort (8 HC, 7 severe and 8 mild patients) showed that THBS1, but not IL17RA, was significantly upregulated, whereas hsa-miR-29a-3p was downregulated, in PBMCs from severe patients. These findings strongly suggest that dysregulated expression of THBS1, IL17RA, and hsa-miR-29a-3p involves severe COVID-19.

Clinical characteristics analysis of COVID-19 patients from the first significant community outbreak by SARS-CoV-2 variant B.1.1.7 in Taiwan as experienced from a single northern medical center

BACKGROUND/PURPOSE

Clinical characteristics of patients in the first community outbreak of coronavirus disease 2019 (COVID-19) by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant B.1.1.7 in Taiwan have not been characterized.

METHODS

SARS-CoV-2 positive specimens from inpatients between May 7 and June 15 in 2021were screen for SARS-CoV-2 B.1.1.7 lineage by VirSNiP assay. Clinical characteristics were reviewed and compared with those from Feb 1 to April 30, 2020 and from Jan 1 to March 31, 2022.

RESULTS

One hundred forty-one inpatients from May 7 to June 15, 2021 infected with SARS-CoV-2 B.1.1.7 lineage were included. The major presenting symptoms were fever (88.7%) and cough (59.6%). Incidence of relevant complications including pulmonary embolism, simultaneous infections with bacteria, virus, and fungi were 0.7%, 12.8%, 13.5%, and 2.1%, respectively. Old age, high Charlson comorbidity index, short of breath, and initial critical illness were independently associated with 28-day mortality (all p < 0.05). In comparison to COVID-19 inpatients from Feb 1 to April 30, 2020, patients from the outbreak by SARS-CoV-2 B.1.1.7 lineage were older, more severe in disease condition, higher mortality but less obvious initial presenting symptoms. After implementation of nationwide vaccination campaign in the next half year of 2021, COVID-19 inpatients from Jan 1 to March 31 in 2022 indicated less severe diseases than those infected with SARS-CoV-2 B.1.1.7 lineage.

CONCLUSION

COVID-19 inpatients by SARS-CoV-2 variant B.1.1.7 with old age, multiple comorbidities, and more severe disease conditions were associated with increased mortality. Vaccination for this vulnerable populations may be helpful.

COVID-19 and Thrombosis: Clinical Aspects

In coronavirus disease 2019 (COVID-19), thrombus formation is related to the pathogenesis of acute respiratory distress syndrome (ARDS) and the progression of clinical symptoms. Severe damage to vascular endothelial cells and the associated cytokine storm after SARS-CoV-2 infection cause thrombogenesis and contribute to the development of more severe and unique thromboses compared to other infectious diseases. Thromboses occur more often in critically ill patients. In addition to pulmonary thromboembolism (PE) and deep vein thrombosis, acute myocardial infarction, peripheral arterial thrombosis, and aortic thrombosis have also been reported. In PE, thrombi develop in both pulmonary arteries and alveolar capillaries. These, together with intraalveolar fibrin deposition, interfere with effective gaseous exchange in the lungs and exacerbate the clinical symptoms of ARDS in patients with COVID-19. Pharmacological thromboprophylaxis is recommended for all hospitalized patients to prevent both thrombosis and aggravation of ARDS, and other organ failures. Although the pediatric population is mostly asymptomatic or develops mild disease after SARS-CoV-2 infection, a new inflammatory disorder affecting the cardiovascular system, multisystem inflammatory syndrome in children (MIS-C), has been reported. Similar to Kawasaki disease, acute myocarditis, coronary vasculitis, and aneurysms are typically seen in MISC, although these two are now considered distinct entities. A similar acute myocarditis is also observed in young male adults, in which a hyperinflammatory state after SARS-CoV-2 infection seems to be involved. Several side effects following vaccination against COVID-19 have been reported, including vaccine-induced immune thrombotic thrombocytopenia and acute myocarditis. Although these could be serious and life-threatening, the cases are very rare, thus, the benefits of immunization still outweigh the risks.

Fibrinogen, Fibrin, and Fibrin Degradation Products in COVID-19

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is the highly pathogenic and highly transmissible human coronavirus that is the causative agent for the worldwide COVID-19 pandemic. COVID-19 manifests predominantly as a respiratory illness with symptoms consistent with viral pneumonia, but other organ systems (e.g., kidney, heart, brain) can also become perturbed in COVID-19 patients. Accumulating data suggest that significant activation of the hemostatic system is a common pathological manifestation of SARS-CoV-2 infection. The clotting protein fibrinogen is one of the most abundant plasma proteins. Following activation of coagulation, the central coagulation protease thrombin converts fibrinogen to fibrin monomers, which selfassemble to form a matrix, the primary structural component of the blood clot. Severe COVID-19 is associated with a profound perturbation of circulating fibrinogen, intra- and extravascular fibrin deposition and persistence, and fibrin degradation. Current findings suggest high levels of fibrinogen and the fibrin degradation product D-dimer are biomarkers of poor prognosis in COVID-19. Moreover, emerging studies with in vitro and animal models indicate fibrin(ogen) as an active player in COVID-19 pathogenesis. Here, we review the current literature regarding fibrin(ogen) and COVID-19, including possible pathogenic mechanisms and treatment strategies centered on clotting and fibrin(ogen) function.

Pathophysiological mechanisms of thrombosis in acute and long COVID-19

COVID-19 patients have a high incidence of thrombosis, and thromboembolic complications are associated with severe COVID-19 and high mortality. COVID-19 disease is associated with a hyper-inflammatory response (cytokine storm) mediated by the immune system. However, the role of the inflammatory response in thrombosis remains incompletely understood. In this review, we investigate the crosstalk between inflammation and thrombosis in the context of COVID-19, focusing on the contributions of inflammation to the pathogenesis of thrombosis, and propose combined use of anti-inflammatory and anticoagulant therapeutics. Under inflammatory conditions, the interactions between neutrophils and platelets, platelet activation, monocyte tissue factor expression, microparticle release, and phosphatidylserine (PS) externalization as well as complement activation are collectively involved in immune-thrombosis. Inflammation results in the activation and apoptosis of blood cells, leading to microparticle release and PS externalization on blood cells and microparticles, which significantly enhances the catalytic efficiency of the tenase and prothrombinase complexes, and promotes thrombin-mediated fibrin generation and local blood clot formation. Given the risk of thrombosis in the COVID-19, the importance of antithrombotic therapies has been generally recognized, but certain deficiencies and treatment gaps in remain. Antiplatelet drugs are not in combination with anticoagulant treatments, thus fail to dampen platelet procoagulant activity. Current treatments also do not propose an optimal time for anticoagulation. The efficacy of anticoagulant treatments depends on the time of therapy initiation. The best time for antithrombotic therapy is as early as possible after diagnosis, ideally in the early stage of the disease. We also elaborate on the possible mechanisms of long COVID thromboembolic complications, including persistent inflammation, endothelial injury and dysfunction, and coagulation abnormalities. The above-mentioned contents provide therapeutic strategies for COVID-19 patients and further improve patient outcomes.

Care of the Seriously Ill Patient with SARS-CoV-2

In late 2019, SARS-CoV-2 caused the greatest global health crisis in a century, impacting all aspects of society. As the COVID-19 pandemic evolved throughout 2020 and 2021, multiple variants emerged, contributing to multiple surges in cases of COVID-19 worldwide. In 2021, highly effective vaccines became available, although the pandemic continues into 2022. There has been tremendous expansion of basic, translational, and clinical knowledge about SARS-CoV-2 and COVID-19 since the pandemic's onset. Treatment options have been rapidly explored, attempting to repurpose preexisting medications in tandem with development and evaluation of novel agents. Care of the seriously ill patient is examined.

Inflammatory and Hemostatic Markers in COVID-19 Patients with Arterial Thrombosis Are Significantly Lower at Hospital Admission than in COVID-19 Patients without Thrombosis

Patients with Coronavirus disease 2019 (COVID-19) are at increased risk of venous thromboembolism (VTE); however, data on arterial thromboembolism (ATE) is still limited. We report a case series of thromboembolic events (TE) in 290 COVID-19 patients admitted between October and December 2020 to a Portuguese hospital. Admission levels of various laboratory parameters were evaluated and compared between COVID-19 patients with (TE) and without thrombotic events (non-TE). The overall incidence of isolated ATE was 5.52%, isolated VTE was 2.41% and multiple mixed events was 0.7%. A total of 68% events were detected upon admission to the hospital with 76% corresponding to ATE. Admissions to the Intensive Care Unit were higher in patients with TE, when comparing with the non-TE group (44% vs. 27.2%; p = 0.003). Patients with ATE presented significantly lower levels of CRP (p = 0.007), ferritin (p = 0.045), LDH (p = 0.037), fibrinogen (p = 0.010) and higher monocyte counts (p = 0.033) comparatively to the non-TE patients. These results point to an early occurrence of TE and an increased incidence of ATE over VTE. The less prominent inflammation markers in patients with TE and the early presence of TE in patients with otherwise no reason for hospitalization, may suggest a direct role of SARS-CoV-2 in the thrombotic process.

Managing Covid-19 in patients with heart failure: current status and future prospects

INTRODUCTION

COVID-19 may contribute to decompensation of previously stable chronic HF or cause a de-novo heart failure, which may come from the hyperinflammatory response and subsequent increase in metabolic demand.

AREAS COVERED

Two independent investigators searched MEDLINE (via PubMed), Europe PMC, and ScienceDirect databases with the following search terms: COVID-19, heart failure, COVID-19 drugs, heart failure drugs, and device therapy. All of the included full-text articles were rigorously evaluated by both authors in case there was disagreement about whether research should be included or not. In total, 157 studies were included and underwent extensive reading by the authors.

EXPERT OPINION

The World Health Organization (WHO) and the National Institute of Health (NIH) have published COVID-19 drug recommendations, although recommendations for HF-specific drug choices in COVID-19 are still lacking. We hope that this review can answer the void of comprehensive research data regarding the management options of HF in the COVID-19 condition so that clinicians can at least choose a more beneficial therapy or avoid combination therapies that have a high burden of side effects on HF; thus, morbidity and mortality in COVID-19 patients with HF may be reduced.

The current status of thrombosis and anticoagulation therapy in patients with COVID-19 in Japan: From the CLOT-COVID study

BACKGROUND

Data on thrombosis and current real-world management strategies for anticoagulation therapy are scarce but important for understanding current issues and unmet needs of an optimal management of patients with coronavirus disease 2019 (COVID-19).

METHOD

The CLOT-COVID Study (thrombosis and antiCoaguLatiOn Therapy in patients with COVID-19 in Japan Study: UMIN000045800) was a retrospective, multicenter cohort study enrolling consecutive hospitalized patients with COVID-19 among 16 centers in Japan from April 2021 to September 2021, and we tried to capture the status of the patients in the fourth and fifth waves of the COVID-19 infections in Japan. We enrolled consecutive hospitalized patients who were diagnosed with COVID-19 and had a positive polymerase chain reaction test obtained from the hospital databases.

RESULTS

Among 2894 patients with COVID-19, 1245 (43%) received pharmacological thromboprophylaxis. The proportion of pharmacological thromboprophylaxis increased according to the severity of the COVID-19 in 9.8% with mild COVID-19, 61% with moderate COVID-19, and 97% with severe COVID-19. The types and doses of anticoagulants varied widely across the participating centers. During the hospitalization, 38 patients (1.3%) and 126 (4.4%) underwent ultrasound examinations for the lower extremities and contrast-enhanced computed tomography examinations, respectively, and 55 (1.9%) developed thrombosis, mostly venous thromboembolism (71%). The incidence of thrombosis increased according to the severity of the COVID-19 in 0.2% with mild COVID-19, 1.4% with moderate COVID-19, and 9.5% with severe COVID-19. Major bleeding occurred in 57 patients (2.0%) and 158 (5.5%) died, and 81% of them were due to respiratory failure from COVID-19 pneumonia.

CONCLUSIONS

In the present large-scale observational study, pharmacological thromboprophylaxis for hospitalized patients with COVID-19 was common especially in patients with severe COVID-19, and management strategies varied widely across the participating centers. The overall incidence of thrombosis was substantially low with an increased incidence according to the severity of the COVID-19.

ISTH guidelines for antithrombotic treatment in COVID-19

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

Approach to Thromboprophylaxis for Prevention of Venous Thromboembolism in COVID-19: Global Updates and Clinical Insights from India

Venous thromboembolism (VTE) frequently occurs in patients with coronavirus disease-19 (COVID-19) and is associated with increased mortality. Several global guidelines recommended prophylactic-intensity anticoagulation rather than intermediate-intensity or therapeutic-intensity anticoagulation for patients with COVID-19-related acute or critical illness without suspected or confirmed VTE. Even though standard doses of thromboprophylaxis are received, many cases of thrombotic complications are reported; hence, appropriate and adequate thromboprophylaxis is critical for the prevention of VTE in COVID-19. In spite of an increased prevalence of VTE in Indian patients, sufficient data on patient characteristics, diagnosis, and therapeutic approach for VTE in COVID is lacking. In this article, we review the available global literature (search conducted up to 31 May 2021) and provide clinical insights into our approach towards managing VTE in patients with COVID-19. Furthermore, in this review, we summarize the incidence and risk factors for VTE with emphasis on the thromboprophylaxis approach in hospitalized patients and special populations with COVID-19 and assess clinical implications in the Indian context.

Use of low molecular weight heparin and hemoglobin fall in COVID-19 patients: A STROBE-compliant study

In patients with coronavirus disease 2019 (COVID-19), anticoagulation was suggested as a mitigating strategy. However, little research has been conducted on the adverse consequences of anticoagulant medication. This study aimed to investigate the adverse effect of low molecular weight heparin (LMWH) on hemoglobin fall in COVID-19 treatment. The electronic medical records of COVID-19 patients with pneumonia were collected (including clinical characteristics, vaccination status, complete blood count, coagulation profile, inflammatory cytokines, serum biochemical indicators, and computerized tomography imaging score). Whether they received LMWH, patients were divided into the LMWH group and the control group. Count data were represented as frequency distribution, and a 2-tailed test was used to compare the 2 groups. Spearman rank correlation was used to evaluate the interrelation between changes in hemoglobin and LMWH. The confounding factors were excluded by logistic regression analysis. A total of 179 COVID-19 pneumonia patients were enrolled (81 in the LMWH group and 98 in the control group). The change in hemoglobin was -6.0g/L (IQR -10.8 to 1.0) in the LMWH group and -2.0g/L (IQR -7.0 to 4.0) in the control group (P < .001, between-group difference, -5.0 g/L; 95% confidence interval, -7.0 to -3.0, calculated with the use of the Mann-Whitney U test and the Hodges-Lehmann estimate of confidence intervals for pseudo-medians). The results of multivariate regression analysis showed that after adjusting for confounding factors, LMWH use was not associated with a decrease in hemoglobin (P > .05). In nonsevere COVID-19 patients with pneumonia, the preventive use of LMWH did not lower hemoglobin.

Ischemic Stroke Due to Heparin-induced Thrombocytopenia during Severe COVID-19 Infection

A 53-year-old woman with severe coronavirus disease 2019 (COVID-19) pneumonia was admitted and treated with intravenous unfractionated heparin for thromboprophylaxis under general anesthesia with mechanical ventilation. She developed right hemiparesis after hospitalization due to a large hemorrhagic infarction. Her platelet count decreased from 243,000/μL at administration to 121,000/μL. Anti-platelet factor 4-heparin antibody testing was positive according to a latex immunoturbidimetric assay. She was therefore diagnosed with heparin-induced thrombocytopenia. We immediately stopped the heparin and started argatroban; the platelet count recovered, and thrombosis did not relapse. Physicians should consider heparin-induced thrombocytopenia as a cause of ischemic stroke in patients with COVID-19 infection.

American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19: January 2022 update on the use of therapeutic-intensity anticoagulation in acutely ill patients

BACKGROUND

COVID-19-related acute illness is associated with an increased risk of venous thromboembolism (VTE).

OBJECTIVE

These evidence-based guidelines from the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in making decisions about the use of anticoagulation in patients with COVID-19.

METHODS

ASH formed a multidisciplinary guideline panel that included patient representatives and applied strategies to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process and performed systematic evidence reviews (through November 2021). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess evidence and make recommendations, which were subject to public comment. This is an update to guidelines published in February 2021 as part of the living phase of these guidelines.

RESULTS

The panel made one additional recommendation. The panel issued a conditional recommendation in favor of therapeutic-intensity over prophylactic-intensity anticoagulation in patients with COVID-19-related acute illness who do not have suspected or confirmed VTE. The panel emphasized the need for an individualized assessment of risk of thrombosis and bleeding. The panel also noted that heparin (unfractionated or low molecular weight) may be preferred because of a preponderance of evidence with this class of anticoagulants.

CONCLUSION

This conditional recommendation was based on very low certainty in the evidence, underscoring the need for additional, high-quality, randomized controlled trials comparing different intensities of anticoagulation in patients with COVID-19-related acute illness.

American Society of Hematology living guidelines on the use of anticoagulation for thromboprophylaxis for patients with COVID-19: March 2022 update on the use of anticoagulation in critically ill patients

BACKGROUND

COVID-19-related critical illness is associated with an increased risk of venous thromboembolism (VTE).

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in decisions about the use of anticoagulation for patients with COVID-19.

METHODS

ASH formed a multidisciplinary guideline panel, including 3 patient representatives, and applied strategies to minimize potential bias from conflicts of interest. The McMaster University Grading of Recommendations Assessment, Development and Evaluation (GRADE) Centre supported the guideline development process, including performing systematic evidence reviews (up to January 2022). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the GRADE approach to assess evidence and make recommendations, which were subject to public comment. This is an update to guidelines published in February 2021 and May 2021 as part of the living phase of these guidelines.

RESULTS

The panel made 1 additional recommendation: a conditional recommendation for the use of prophylactic-intensity over therapeutic-intensity anticoagulation for patients with COVID-19-related critical illness who do not have suspected or confirmed VTE. The panel emphasized the need for an individualized assessment of thrombotic and bleeding risk.

CONCLUSIONS

This conditional recommendation was based on very low certainty in the evidence, underscoring the need for additional, high-quality, randomized controlled trials comparing different intensities of anticoagulation for patients with COVID-19-related critical illness.

C-reactive protein, immunothrombosis and venous thromboembolism

C-reactive protein (CRP) is a member of the highly conserved pentraxin superfamily of proteins and is often used in clinical practice as a marker of infection and inflammation. There is now increasing evidence that CRP is not only a marker of inflammation, but also that destabilized isoforms of CRP possess pro-inflammatory and pro-thrombotic properties. CRP circulates as a functionally inert pentameric form (pCRP), which relaxes its conformation to pCRP* after binding to phosphocholine-enriched membranes and then dissociates to monomeric CRP (mCRP). with the latter two being destabilized isoforms possessing highly pro-inflammatory features. pCRP* and mCRP have significant biological effects in regulating many of the aspects central to pathogenesis of atherothrombosis and venous thromboembolism (VTE), by directly activating platelets and triggering the classical complement pathway. Importantly, it is now well appreciated that VTE is a consequence of thromboinflammation. Accordingly, acute VTE is known to be associated with classical inflammatory responses and elevations of CRP, and indeed VTE risk is elevated in conditions associated with inflammation, such as inflammatory bowel disease, COVID-19 and sepsis. Although the clinical data regarding the utility of CRP as a biomarker in predicting VTE remains modest, and in some cases conflicting, the clinical utility of CRP appears to be improved in subsets of the population such as in predicting VTE recurrence, in cancer-associated thrombosis and in those with COVID-19. Therefore, given the known biological function of CRP in amplifying inflammation and tissue damage, this raises the prospect that CRP may play a role in promoting VTE formation in the context of concurrent inflammation. However, further investigation is required to unravel whether CRP plays a direct role in the pathogenesis of VTE, the utility of which will be in developing novel prophylactic or therapeutic strategies to target thromboinflammation.

Venous Thromboembolic Disease in COVID-19, Pathophysiology, Therapy and Prophylaxis

For over two years, the world has been facing the epidemiological and health challenge of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Growing problems are also complications after the development of COVID-19 in the form of post and long- COVID syndromes, posing a challenge for the medical community, both for clinicians and the scientific world. SARS-CoV-2 infection is associated with an increased risk of cardiovascular complications, especially thromboembolic complications, which are associated with both thrombosis of small and very small vessels due to immunothrombosis, and the development of venous thromboembolism. Low molecular wight heparin (LMHW) are the basic agents used in the prevention and treatment of thromboembolic complications in COVID-19. There is still a great deal of controversy regarding both the prevention and treatment of thromboembolic complications, including the prophylaxis dose or the optimal duration of anticoagulant treatment in patients with an episode of venous thromboembolism.

Strategies for Cardio-Oncology Care During the COVID-19 Pandemic

Purpose of review

The COVID-19 pandemic has disrupted healthcare and has disproportionately affected the marginalized populations. Patients with cancer and cardiovascular disease (cardio-oncology population) are uniquely affected. In this review, we explore the current data on COVID-19 vulnerability and outcomes in these patients and discuss strategies for cardio-oncology care with a focus on healthcare innovation, health equity, and inclusion.

Recent findings

The growing evidence suggest increased morbidity and mortality from COVID-19 in patients with comorbid cancer and cardiovascular disease. Additionally, de novo cardiovascular complications such as myocarditis, myocardial infarction, arrhythmia, heart failure, and thromboembolic events have increasingly emerged, possibly due to an accentuated host immune response and cytokine release syndrome.

Summary

Patient-centric policies are helpful for cardio-oncology surveillance like remote monitoring, increased use of biomarker-based surveillance, imaging modalities like CT scan, and point-of-care ultrasound to minimize the exposure for high-risk patients. Abundant prior experience in cancer therapy scaffolded the repurposed use of corticosteroids, IL-6 inhibitors, and Janus kinase inhibitors in the treatment of COVID-19 infection. COVID-19 vaccine timing and dose frequency present a challenge due to overlapping toxicities and immune cell depletion in patients receiving cancer therapies. The SARS-CoV-2 pandemic laid bare social and ethnic disparities in healthcare but also steered in innovation to combat problems of patient outreach, particularly with virtual care. In the recovery phase, the backlog in cardio-oncology care, interplay of cancer therapy-related side effects, and long COVID-19 syndrome are crucial issues to address.

Sex and gender differences in community-acquired pneumonia

Awareness of the influence of sex ands gender on the natural history of several diseases is increasing. Community-acquired pneumonia (CAP) is the most common acute respiratory disease, and it is associated with both morbidity and mortality across all age groups. Although a role for sex- and gender-based differences in the development and associated complications of CAP has been postulated, there is currently high uncertainty on the actual contribution of these factors in the epidemiology and clinical course of CAP. More evidence has been produced on the topic during the last decades, and sex- and gender-based differences have also been extensively studied in COVID-19 patients since the beginning of the SARS-CoV-2 pandemic. This review aims to provide an extensive outlook of the role of sex and gender in the epidemiology, pathogenesis, treatment, and outcomes of patients with CAP, and on the future research scenarios, with also a specific focus on COVID-19.

COVID-19 and antiphospholipid antibodies

Antiphospholipid syndrome and the coagulopathy of COVID-19 share many pathophysiologic features, including endotheliopathy, hypercoagulability, and activation of platelets, complement pathways, and neutrophil extracellular traps, all acting in concert via a model of immunothrombosis. Antiphospholipid antibody production in COVID-19 is common, with 50% of COVID-19 patients being positive for lupus anticoagulant in some studies, and with non-Sapporo criteria antiphospholipid antibodies being prevalent as well. The biological significance of antiphospholipid antibodies in COVID-19 is uncertain, as such antibodies are usually transient, and studies examining clinical outcomes in COVID-19 patients with and without antiphospholipid antibodies have yielded conflicting results. In this review, we explore the biology of antiphospholipid antibodies in COVID-19 and other infections and discuss mechanisms of thrombogenesis in antiphospholipid syndrome and parallels with COVID-19 coagulopathy. In addition, we review the existing literature on safety of COVID-19 vaccination in patients with antiphospholipid antibodies and antiphospholipid syndrome.

Cerebral Venous Sinus Thrombosis Associated With Coronavirus Disease 2019: Case Report and Review of the Literature

INTRODUCTION

Coronavirus disease 2019 (COVID-19) is associated with significant risk of acute thrombosis. We present a case report of a patient with cerebral venous sinus thrombosis (CVST) associated with COVID-19 and performed a literature review of CVST associated with COVID-19 cases.

CASE REPORT

A 38-year-old woman was admitted with severe headache and acute altered mental status a week after confirmed diagnosis of COVID-19. Magnetic resonance imaging brain showed diffuse venous sinus thrombosis involving the superficial and deep veins, and diffuse edema of bilateral thalami, basal ganglia and hippocampi because of venous infarction. Her neurological exam improved with anticoagulation (AC) and was subsequently discharged home. We identified 43 patients presenting with CVST associated with COVID-19 infection. 56% were male with mean age of 51.8±18.2 years old. The mean time of CVST diagnosis was 15.6±23.7 days after onset of COVID-19 symptoms. Most patients (87%) had thrombosis of multiple dural sinuses and parenchymal changes (79%). Almost 40% had deep cerebral venous system thrombosis. Laboratory findings revealed elevated mean D-dimer level (7.14/mL±12.23 mg/L) and mean fibrinogen level (4.71±1.93 g/L). Less than half of patients had prior thrombotic risk factors. Seventeen patients (52%) had good outcomes (mRS <=2). The mortality rate was 39% (13 patients).

CONCLUSION

CVST should be in the differential diagnosis when patients present with acute neurological symptoms in this COVID pandemic. The mortality rate of CVST associated with COVID-19 can be very high, therefore, early diagnosis and prompt treatment are crucial to the outcomes of these patients.

Increased Susceptibility for Thromboembolic Events versus High Bleeding Risk Associated with COVID-19

The infection with the SARS-CoV-2 virus is associated with numerous systemic involvements. Besides the severe respiratory injuries and cardiovascular complications, it became obvious early on that this disease carries an increased risk of thromboembolic events, but a higher propensity for bleedings as well. We researched the medical literature over significant PubMed published articles debating on the prevalence, category of patients, the moment of occurrence, and evolution of venous thromboembolism (VTE), but also of venous and arterial “in situ” thrombosis (AT), and hemorrhagic events as well. Most researchers agree on an increased prevalence of thromboembolic events, ranging between 25 and 31% for VTE, depending on the analyzed population. For AT and hemorrhagic complications lower rates were reported, namely, about 2–3%, respectively, between 4.8 and 8%, occurring mostly in older patients, suffering from moderate/severe forms of COVID-19, with associated comorbidities. It is important to mention that patients suffering from hemorrhages frequently received thromboprophylaxis with anticoagulant drugs. As a consequence of thromboembolic and hemorrhagic complications which are both important negative prognostic factors, the evolution of patients infected with the SARS-CoV-2 virus is aggravated, determining an augmented morbidity and mortality of this population.

Thromboembolic events in deceased patients with proven SARS-CoV-2 infection: Frequency, characteristics and risk factors

BACKGROUND

Infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) results in respiratory syndromes but also in vascular complications such as thromboembolism (TE). In this regard, immunothrombosis, resulting from inflammation in SARS-CoV-2 infected tissues, has been described. Data on TE in COVID-19 are mainly based on clinical observational and/or incomplete autopsy studies. The true burden of TE and the relevance of genetic predisposition, however, have not been resolved.

OBJECTIVES

Here, we report on a consecutive cohort of 100 fully autopsied patients deceased by SARS-CoV-2 infections during the first wave of the pandemic (March to April 2020). We investigated the localization of TE, potential clinical risk factors, and the prothrombotic gene mutations, factor V Leiden and prothrombin G20210A, in postmortem blood or tissue samples.

RESULTS

TE was found in 43/100 autopsies. 93 % of TE events were venous occlusions, with 23 patients having pulmonary thromboembolism (PT) with or without lower-extremity deep vein thrombosis. Of these, 70 % showed PT restricted to (sub)segmental arteries, consistent with in situ immunothrombosis. Patients with TE had a significantly higher BMI and died more frequently at an intensive care unit. Hereditary thrombophilia factors were not associated with TE.

CONCLUSIONS

Our autopsy results show that a significant proportion of SARS-CoV-2 infected patients suffer from TE, affecting predominantly the venous system. Orthotopic peripheral PT was the most frequent finding. Hereditary thrombophilia appears not to be a determinant for TE in COVID-19. However, obesity and the need for intensive care increase the risk of TE in these patients.

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.

Thrombotic and bleeding complications in patients with chronic lymphocytic leukemia and severe COVID-19: a study of ERIC, the European Research Initiative on CLL

Background

Patients with chronic lymphocytic leukemia (CLL) may be more susceptible to COVID-19 related poor outcomes, including thrombosis and death, due to the advanced age, the presence of comorbidities, and the disease and treatment-related immune deficiency. The aim of this study was to assess the risk of thrombosis and bleeding in patients with CLL affected by severe COVID-19.

Methods

This is a retrospective multicenter study conducted by ERIC, the European Research Initiative on CLL, including patients from 79 centers across 22 countries. Data collection was conducted between April and May 2021. The COVID-19 diagnosis was confirmed by the real-time polymerase chain reaction (RT-PCR) assay for SARS-CoV-2 on nasal or pharyngeal swabs. Severe cases of COVID-19 were defined by hospitalization and the need of oxygen or admission into ICU. Development and type of thrombotic events, presence and severity of bleeding complications were reported during treatment for COVID-19. Bleeding events were classified using ISTH definition. STROBE recommendations were used in order to enhance reporting.

Results

A total of 793 patients from 79 centers were included in the study with 593 being hospitalized (74.8%). Among these, 511 were defined as having severe COVID: 162 were admitted to the ICU while 349 received oxygen supplementation outside the ICU. Most patients (90.5%) were receiving thromboprophylaxis. During COVID-19 treatment, 11.1% developed a thromboembolic event, while 5.0% experienced bleeding. Thrombosis developed in 21.6% of patients who were not receiving thromboprophylaxis, in contrast to 10.6% of patients who were on thromboprophylaxis. Bleeding episodes were more frequent in patients receiving intermediate/therapeutic versus prophylactic doses of low-molecular-weight heparin (LWMH) (8.1% vs. 3.8%, respectively) and in elderly. In multivariate analysis, peak D-dimer level and C-reactive protein to albumin ratio were poor prognostic factors for thrombosis occurrence (OR = 1.022, 95%CI 1.007‒1.038 and OR = 1.025, 95%CI 1.001‒1.051, respectively), while thromboprophylaxis use was protective (OR = 0.199, 95%CI 0.061‒0.645). Age and LMWH intermediate/therapeutic dose administration were prognostic factors in multivariate model for bleeding (OR = 1.062, 95%CI 1.017–1.109 and OR = 2.438, 95%CI 1.023–5.813, respectively).

Conclusions

Patients with CLL affected by severe COVID-19 are at a high risk of thrombosis if thromboprophylaxis is not used, but also at increased risk of bleeding under the LMWH intermediate/therapeutic dose administration.

Coagulopathy of Dengue and COVID-19: Clinical Considerations

Thrombocytopenia and platelet dysfunction commonly occur in both dengue and COVID-19 and are related to clinical outcomes. Coagulation and fibrinolytic pathways are activated during an acute dengue infection, and endothelial dysfunction is observed in severe dengue. On the other hand, COVID-19 is characterised by a high prevalence of thrombotic complications, where bleeding is rare and occurs only in advanced stages of critical illness; here thrombin is the central mediator that activates endothelial cells, and elicits a pro-inflammatory reaction followed by platelet aggregation. Serological cross-reactivity may occur between COVID-19 and dengue infection. An important management aspect of COVID-19-induced immunothrombosis associated with thrombocytopenia is anticoagulation with or without aspirin. In contrast, the use of aspirin, nonsteroidal anti-inflammatory drugs and anticoagulants is contraindicated in dengue. Mild to moderate dengue infections are treated with supportive therapy and paracetamol for fever. Severe infection such as dengue haemorrhagic fever and dengue shock syndrome often require escalation to higher levels of support in a critical care facility. The role of therapeutic platelet transfusion is equivocal and should not be routinely used in patients with dengue with thrombocytopaenia and mild bleeding. The use of prophylactic platelet transfusion in dengue fever has strained financial and healthcare systems in endemic areas, together with risks of transfusion-transmitted infections in low- and middle-income countries. There is a clear research gap in the management of dengue with significant bleeding.

Anticoagulation in hospitalized patients with COVID-19

Coronavirus disease-19 (COVID-19) includes a thromboinflammatory syndrome that may manifest with microvascular and macrovascular thrombosis. Patients with COVID-19 have a higher incidence of venous thromboembolism than other hospitalized patients. Three randomized control trials suggesting benefit of therapeutic heparin in hospitalized noncritically ill patients with COVID-19 have led to conditional guideline recommendations for this treatment. By contrast, prophylactic-dose heparin is recommended for critically ill patients. Unprecedented collaboration and rapidly funded research have improved care of hospitalized patients with COVID-19.

Pulmonary embolism in a patient with eltrombopag-treated aplastic anaemia and paroxysmal nocturnal haemoglobinuria clone during COVID-19 pneumonia

Thrombosis in patients with thrombocytopenia has several risk factors, both disease-related and treatment-associated. Recently, COVID-19 infection was recognized as an additional risk factor, further complicating the delicate balance between thrombosis and bleeding in these patients. Here we describe the case of a patient with aplastic anaemia on eltrombopag who developed pulmonary embolism during COVID-19 pneumonia, despite receiving oral anticoagulation with edoxaban. Notably, he was also carrying a large paroxysmal nocturnal haemoglobinuria clone, although without evidence of haemolysis. The presented case recapitulates some of the open questions in thrombotic risk management of cytopenic patients, such as the management of thrombopoietin receptor agonists and the choice of anticoagulation in PNH, while also accounting for the additional thrombotic risk linked to COVID-19.

The prevalence of vascular complications in SARS-CoV-2 infected outpatients

Background

The risk of thromboembolic events is increased for coronavirus disease (COVID)-19 inpatients. For severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected outpatients, only few data are available so far.

Methods

In our prospective single-center study, 461 SARS-CoV-2-infected outpatients were screened for the presence of deep vein thrombosis.

Results

Two outpatients had suffered a deep vein thrombosis. An association with previously known risk factors, such as preexisting thrombosis in the medical history or cardiovascular risk factors, could not be proven.

Conclusion

General thromboprophylaxis in SARS-CoV-2-infected outpatients is still not recommended.

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.

Thromboembolic events in COVID-19 ambulatory patients: An observational study about incidence, and thromboprophylaxis outcomes

Introduction

There are no clear data about the incidence and the prophylactic strategies of arterial and venous thromboembolic events (TE) in COVID-19 ambulatory patients. Thus, we conducted this study to analyze thromboembolic complications in this setting and to assess thromboprophylaxis management and outcomes in the real life.

Patients and methods

This is an observational study including Covid-19 ambulatory patients. We assessed incidence of venous and arterial TE events as well as thromboprophylaxis outcomes and hemorrhagic complications. We defined high risk thrombo-embolic factor according to the Belgian guidelines which are the only guidelines that described thromboprophylaxis in COVID-19 ambulatory patients.

Results

We included 2089 patients with a mean age of 43±16 years. The incidence of 30 days venous and arterial TE complications in our cohort was 1%. Venous thromboembolic complications occurred in 0.8% and arterial thromboembolic complications occurred in 0.3%.We noted at least one high-risk TE factor in 18.5% of patients but thromboprophylaxis was prescribed in 22.5% of the cases, LMWH in 18.1%, and Rivaroxaban in 3.7%. Hemorrhagic events occurred in eight patients (0.3%): five patients showed minor hemorrhagic events and three patients showed major ones (0.14%).

Conclusions

Our study showed that the incidence of thromboembolic complications is very low in COVID-19 ambulatory patients. Paradoxically, there is an over prescription of thrombo-prophylaxis in this population.

Efficacy and safety of heparin full-dose anticoagulation in hospitalized non-critically ill COVID-19 patients: a meta-analysis of multicenter randomized controlled trials

Arterial and venous thrombotic events in COVID-19 cause significant morbidity and mortality among patients. Although international guidelines agree on the need for anticoagulation, it is unclear whether full-dose heparin anticoagulation confers additional benefits over prophylactic-dose anticoagulation. This systematic review and meta-analysis aimed to investigate the efficacy and safety of heparin full-dose anticoagulation in hospitalized non-critically ill COVID-19 patients. We searched Pubmed/Medline, EMBASE, Clinicaltrials.gov, medRxiv.org and Cochrane Central Register of clinical trials dated up to April 2022. Randomized controlled trials (RCTs) comparing full-dose heparin anticoagulation to prophylactic-dose anticoagulation or standard treatment in hospitalized non-critically ill COVID-19 patients were included in our pooled analysis. The primary endpoint was the rate of major thrombotic events and the co-primary endpoint was the rate of major bleeding events. We identified 4 studies, all of them multicenter, randomizing 2926 patients. Major thrombotic events were 23/1524 (1.5%) in full-dose heparin anticoagulation versus 57/1402 (4.0%) in prophylactic-dose [relative risk (RR) 0.39; 95% confidence interval (CI) 0.25–0.62; p˂0.01; I² = 0%]. Clinical relevant bleeding events occurred in 1.7% (26/1524) among patients treated with heparin full anticoagulation dose compared to 1.1% (15/1403) in prophylactic-dose group (RR 1.60; 95% CI 0.85–3.03; p = 0.15; I² = 20%). Mortality was 6.6% (101/1524) versus 8.6% (121/1402) (RR 0.63; 95% CI 0.33–1.19; p = 0.15). In this meta-analysis of high quality multicenter randomized trials, full-dose anticoagulation with heparin was associated with lower rate of major thrombotic events without differences in bleeding risk and mortality in hospitalized non critically ill COVID-19 patients.

Study registration PROSPERO, review no. CRD42022301874.

Estimating incidence of venous thromboembolism in COVID-19: Methodological considerations

Background

Coagulation abnormalities and coagulopathy are recognized as consequences of severe acute respiratory syndrome coronavirus 2 infection and the resulting coronavirus disease 2019 (COVID-19). Specifically, venous thromboembolism (VTE) has been reported as a frequent complication. By May 27, 2021, at least 93 original studies and 25 meta-analyses investigating VTE incidence in patients with COVID-19 had been published, showing large heterogeneity in reported VTE incidence ranging from 0% to 85%. This large variation complicates interpretation of individual study results as well as comparisons across studies, for example, to investigate changes in incidence over time, compare subgroups, and perform meta-analyses.

Objectives

This study sets out to provide an overview of sources of heterogeneity in VTE incidence studies in patients with COVID-19, illustrated using examples.

Methods

The original studies of three meta-analyses were screened and a list of sources of heterogeneity that may explain observed heterogeneity across studies was composed.

Results

The sources of heterogeneity in VTE incidence were classified as clinical sources and methodologic sources. Clinical sources of heterogeneity include differences between studies regarding patient characteristics that affect baseline VTE risk and protocols used for VTE testing. Methodologic sources of heterogeneity include differences in VTE inclusion types, data quality, and the methods used for data analysis.

Conclusions

To appreciate reported estimates of VTE incidence in patients with COVID-19 in relation to its etiology, prevention, and treatment, researchers should unambiguously report about possible clinical and methodological sources of heterogeneity in those estimates. This article provides suggestions for that.

Association of D-dimer with short-term risk of venous thromboembolism in acutely ill medical patients: A systematic review and meta-analysis

BACKGROUND

D-dimer, a marker of ongoing procoagulant activity, has been widely used for the diagnosis of venous thromboembolism (VTE). The prognostic significance of D-dimer in stratifying VTE risk for acutely ill medical patients has not been well-established.

METHODS

A literature search was performed to collect studies that compared the incidence of short-term VTE between acutely ill medical patients with elevated or nonelevated D-dimer levels. The cutoff of D-dimer was 0.5 μg/mL or otherwise defined by included studies. The study endpoint was any occurrence of VTE (inclusive of deep vein thrombosis [DVT], pulmonary embolism, or VTE-related death) within 90 days of hospital presentation. A meta-analytic approach was employed to estimate the odds ratio (OR) with 95% CI by fitting random-effects models using the generic inverse variance weighted approach.

RESULTS

A total of 10 studies representing 31,119 acutely ill medical patients were included. Compared to those with nonelevated D-dimer levels, patients with elevated D-dimer had approximately threefold greater odds for short-term VTE within 90 days (OR, 3.28; 95% CI, 2.44 to 4.40; p < 0.0001). The association of elevated D-dimer with VTE composite (OR, 3.33; 95% CI, 2.20 to 5.02) and with DVT (OR, 3.26; 95% CI, 2.32 to 4.58) was comparable. The association was significant among patients who presented various acute medical illness (OR, 2.68; 95% CI, 2.01 to 3.58) and those who presented with acute stroke (OR, 3.25; 95% CI, 2.31 to 4.58).

CONCLUSION

Elevation of D-dimer was predictive of the occurrence of VTE within 90 days among acutely ill medical patients. PROSPERO Registration ID: CRD42021264555.

Venous or arterial thrombosis and deaths among COVID-19 cases: a European network cohort study

Background

There are few data on the incidence of thrombosis among COVID-19 cases, with most research concentrated on hospitalised patients. We aimed to estimate the incidence of venous thromboembolism, arterial thromboembolism, and death among COVID-19 cases and to assess the impact of these events on the risks of hospitalisation and death.

Methods

We conducted a distributed network cohort study using primary care records from the Netherlands, Italy, Spain, and the UK, and outpatient specialist records from Germany. The Spanish database was linked to hospital admissions. Participants were followed up from the date of a diagnosis of COVID-19 or positive RT-PCR test for SARS-CoV-2 (index date) for 90 days. The primary study outcomes were venous thromboembolic events, arterial thromboembolic events, and death, all over the 90 days from the index date. We estimated cumulative incidences for the study outcomes. Multistate models were used to calculate adjusted hazard ratios (HRs) for the association between venous thromboembolism or arterial thromboembolism occurrence and risks of hospitalisation or COVID-19 fatality.

Findings

Overall, 909 473 COVID-19 cases and 32 329 patients hospitalised with COVID-19 on or after Sept 1, 2020, were studied. The latest index dates across the databases ranged from Jan 30, 2021, to July 31, 2021. Cumulative 90-day incidence of venous thromboembolism ranged from 0·2% to 0·8% among COVID-19 cases, and up to 4·5% for those hospitalised. For arterial thromboembolism, estimates ranged from 0·1% to 0·8% among COVID-19 cases, increasing to 3·1% among those hospitalised. Case fatality ranged from 1·1% to 2·0% among patients with COVID-19, rising to 14·6% for hospitalised patients. The occurrence of venous thromboembolism in patients with COVID-19 was associated with an increased risk of death (adjusted HRs 4·42 [3·07–6·36] for those not hospitalised and 1·63 [1·39–1·90] for those hospitalised), as was the occurrence of arterial thromboembolism (3·16 [2·65–3·75] and 1·93 [1·57–2·37]).

Interpretation

Risks of venous thromboembolism and arterial thromboembolism were up to 1% among COVID-19 cases, and increased with age, among males, and in those who were hospitalised. Their occurrence was associated with excess mortality, underlying the importance of developing effective treatment strategies that reduce their frequency.

Funding

European Medicines Agency.

Hormonal therapies and venous thrombosis: Considerations for prevention and management

Background

Venous thromboses are well-established complications of hormonal therapy. Thrombosis risk is seen with both hormonal contraceptive agents and with hormone replacement therapy for menopause and gender transition. Over the past several decades, large epidemiological studies have helped better define these risks.

Objectives

To review and discuss the differences in thrombosis risk of the many of hormonal preparations available as well as their interaction with patient-specific factors.

Methods

We conducted a narrative review of the available literature regarding venous thrombosis and hormonal therapies including for contraception, menopausal symptoms, and gender transition.

Results

Thrombosis risk with estrogen-containing compounds increases with increasing systemic dose of estrogen. While progesterone-only-containing products are not associated with thrombosis, when paired with estrogen in combined oral contraceptives, the formulation of progesterone does impact the risk. These components, along with patient-specific factors, may influence the choice of hormonal preparation. For patients who develop thrombosis on hormonal treatment, anticoagulation is protective against future thrombosis. Duration of anticoagulation is dependent on ongoing and future hormone therapy choice. Finally, the optimal management of hormone therapy for individuals diagnosed with prothrombotic illnesses such as COVID-19 remains unclear.

Conclusions

When contemplating hormonal contraception or hormone replacement therapy, clinicians must consider a variety of factors including hormone type, dose, route, personal and family history of thrombosis, and other prothrombotic risk factors to make informed, personalized decisions regarding the risk of venous thrombosis.

Vasculopathy in COVID-19

COVID-19 is a primary respiratory illness that is frequently complicated by systemic involvement of the vasculature. Vascular involvement leads to an array of complications ranging from thrombosis to pulmonary edema secondary to loss of barrier function. This review will address the vasculopathy of COVID-19 with a focus on the role of the endothelium in orchestrating the systemic response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The endothelial receptor systems and molecular pathways activated in the setting of COVID-19 and the consequences of these inflammatory and prothrombotic changes on endothelial cell function will be discussed. The sequelae of COVID-19 vascular involvement at the level of organ systems will also be addressed, with an emphasis on the pulmonary vasculature but with consideration of effects on other vascular beds. The dramatic changes in endothelial phenotypes associated with COVID-19 has enabled the identification of biomarkers that could help guide therapy and predict outcomes. Knowledge of vascular pathogenesis in COVID-19 has also informed therapeutic approaches that may control its systemic sequelae. Because our understanding of vascular response in COVID-19 continues to evolve, we will consider areas of controversy, such as the extent to which SARS-CoV-2 directly infects endothelium and the degree to which vascular responses to SARS-CoV-2 are unique or common to those of other viruses capable of causing severe respiratory disease. This conceptual framework describing how SARS-CoV-2 infection affects endothelial inflammation, prothrombotic transformation, and barrier dysfunction will provide a context for interpreting new information as it arises addressing the vascular complications of COVID-19.

Clinical features of thrombosis and bleeding in COVID-19

Infection with the SARS-CoV-2 virus, resulting in COVID-19 disease, has presented a unique scenario associated with high rates of thrombosis. The risk of venous thrombosis is some three- to sixfold higher than for patients admitted to a hospital for other indications, and for patients who have thrombosis, mortality appears to increase. Thrombosis may be a presenting feature of COVID-19. Pulmonary thrombi are the most frequent events, some related to deep vein thrombosis, but also to in situ microvascular and macrovascular thrombosis. Other venous thromboses include catheter- and circuit-associated in patients requiring hemofiltration and extracorporeal membrane oxygenation. Arterial thrombosis is less commonly documented, with 3% of patients in intensive care units having major arterial strokes and up to 9% having myocardial infarction, both of which are most likely multifactorial. Risk factors for thrombosis above those already documented in hospital settings include duration of COVID-19 symptoms before admission to the hospital. Laboratory parameters associated with higher risk of thrombosis include higher D-dimer, low fibrinogen, and low lymphocyte count, with higher factor VIII and von Willebrand factor levels indicative of more severe COVID-19 infection. All patients should receive thromboprophylaxis when admitted with COVID-19 infection, but the dose and length of treatment are still debated. Thrombosis continues to be treated according to standard VTE guidelines, but adjustments may be needed depending on other factors relevant to the patient's admission.

Complement-mediated microvascular injury and thrombosis in the pathogenesis of severe COVID-19: A review

Coronavirus disease 2019 (COVID-19) causes acute microvascular thrombosis in both venous and arterial structures which is highly associated with increased mortality. The mechanisms leading to thromboembolism are still under investigation. Current evidence suggests that excessive complement activation with severe amplification of the inflammatory response (cytokine storm) hastens disease progression and initiates complement-dependent cytotoxic tissue damage with resultant prothrombotic complications. The concept of thromboinflammation, involving overt inflammation and activation of the coagulation cascade causing thrombotic microangiopathy and end-organ damage, has emerged as one of the core components of COVID-19 pathogenesis. The complement system is a major mediator of the innate immune response and inflammation and thus an appealing treatment target. In this review, we discuss the role of complement in the development of thrombotic microangiopathy and summarize the current data on complement inhibitors as COVID-19 therapeutics.

Examining D-dimer and Empiric Anti-coagulation in COVID-19-Related Thrombosis

Objective

Thrombosis is thought to occur frequently in the setting of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We aimed to elucidate the relationship between macro/microvascular thrombosis, D-dimer levels, and empiric anticoagulation in coronavirus disease 2019 (COVID-19).

Methods

This was an exploratory prospective, single-site, observational study. Adult emergency department patients with COVID-19 requiring hospitalization received a point-of-care lower extremity venous duplex ultrasound. The primary endpoint was thromboembolism and associated D-dimer level. Secondary endpoints included rates of micro and macro thrombotic complications as well as empiric anticoagulant use.

Results

Between January 13^th and April 12^th 2021, 52 patients were enrolled. Median D-dimer at presentation was 650 ng/mL (range 250-10,000 ng/mL) among patients with negative duplex studies. During hospitalization, 18 patients underwent 20 additional studies assessing for venous thromboembolism (VTE). These studies yielded one deep vein thrombosis (DVT) diagnosis. Among patients with negative studies median D-dimer was 1,246 ng/mL (range 329-10,000 ng/mL). Two patients experienced microvascular complications. Seven patients were started on empiric full dose anticoagulation.

Conclusion

While VTE remains a major concern amongst patients with COVID-19, the normal D-dimer cut off of >500 ng/mL likely should not be used to initiate further VTE workup. Additionally, moderately elevated D-dimer did not correlate strongly with microvascular complications and may not be relevant in the decision to initiate empiric anticoagulation.

Process- and product-related impurities in the ChAdOx1 nCov-19 vaccine

ChAdOx1 nCov-19 and Ad26.COV2.S are approved vaccines inducing protective immunity against SARS-CoV-2 infection in humans by expressing the Spike protein of SARS-CoV-2. We analyzed protein content and protein composition of ChAdOx1 nCov-19 and Ad26.COV2.S by biochemical methods and by mass spectrometry. Four out of four tested lots of ChAdOx1 nCoV-19 contained significantly higher than expected levels of host cell proteins (HCPs) and of free viral proteins. The most abundant contaminating HCPs belonged to the heat-shock protein and cytoskeletal protein families. The HCP content exceeded the 400 ng specification limit per vaccine dose, as set by the European Medicines Agency (EMA) for this vaccine, by at least 25-fold and the manufacturer’s batch-release data in some of the lots by several hundred-fold. In contrast, three tested lots of the Ad26.COV2.S vaccine contained only very low amounts of HCPs. As shown for Ad26.COV2.S production of clinical grade adenovirus vaccines of high purity is feasible at an industrial scale. Correspondingly, purification procedures of the ChAdOx1 nCov-19 vaccine should be modified to remove protein impurities as good as possible. Our data also indicate that standard quality assays, as they are used in the manufacturing of proteins, have to be adapted for vectored vaccines.

Extended post-discharge thromboprophylaxis in hospitalized COVID-19 patients

INTRODUCTION

Hospitalized COVID-19 patients, particularly those with high risk features, are at risk for venous and arterial thromboembolic events for approximately 30 days or more after hospital discharge. Extended post-hospital discharge thromboprophylaxis has potential to reduce this risk.

AREAS COVERED

Recent cohort, registry, and randomized trial data on the topic of extended post-discharge thromboprophylaxis in COVID-19 inpatients are reviewed, and key patient subgroups at high thrombotic risk are highlighted, with antithrombotic guidelines on the topic discussed.

EXPERT OPINION

COVID-19 inpatients with cardiovascular risk factors, advanced age, intensive care unit stay, or an IMPROVE VTE score of 4 or more or a score of 2 or 3 plus elevated D-dimers (> twice the upper limit of normal) or an IMPROVE-DD VTE score of ≥ 4 are at high thrombotic risk in the post-discharge period. These high risk patient subgroups benefit from extended post-discharge thromboprophylaxis, specifically with rivaroxaban 10mg daily for 35 days. Recent NIH and ISTH guidelines recommend or suggest this approach. Results from other clinical trials are pending.

A comprehensive review of adverse events to drugs used in COVID-19 patients: Recent clinical evidence

BACKGROUND

Since the breakthrough of the pandemic, several drugs have been used to treat COVID-19 patients. This review aims to gather information on adverse events (AE) related to most drugs used in this context.

METHODS

We performed a literature search to find articles that contained information about AE in COVID-19 patients. We analysed and reviewed the most relevant studies in the Medline (via PubMed), Scopus and Web of Science. The most frequent AE identified were grouped in our qualitative analysis by System Organ Class (SOC), the highest level of the MedDRA medical terminology for each of the drugs studied.

RESULTS

The most frequent SOCs among the included drugs are investigations (n = 7 drugs); skin and subcutaneous tissue disorders (n = 5 drugs); and nervous system disorders, infections and infestations, gastrointestinal disorders, hepatobiliary disorders, and metabolism and nutrition disorders (n = 4 drugs). Other SOCs also emerged, such as general disorders and administration site conditions, renal and urinary disorders, vascular disorders and cardiac disorders (n = 3 drugs). Less frequent SOC were eye disorders, respiratory, thoracic and mediastinal disorders, musculoskeletal and connective tissue disorders, and immune system disorders (n = 2 drugs). Psychiatric disorders, and injury, poisoning and procedural complications were also reported (n = 1 drug).

CONCLUSIONS

Some SOCs seem to be more frequent than others among the COVID-19 drugs included, although neither of the studies included reported causality analysis. For that purpose, further clinical studies with robust methodologies, as randomised controlled trials, should be designed and performed.

Thromboprophylaxis in people hospitalized with COVID-19: Assessing intermediate or standard doses in a retrospective cohort study

Background and Objectives

Current clinical guidelines recommend thromboprophylaxis for adults hospitalized with coronavirus disease 2019 (COVID-19), yet it is unknown whether higher doses of thromboprophylaxis offer benefits beyond standard doses.

Methods

We studied electronic health records from 50 091 adults hospitalized with COVID-19 in the United States between February 2020 and February 2021. We compared standard (enoxaparin 30 or 40 mg/day, fondaparinux 2.5 mg, or heparin 5000 units twice or thrice per day) versus intermediate (enoxaparin 30 or 40 mg twice daily, or up to 1.2 mg/kg of body weight daily, heparin 7500 units thrice per day or heparin 10 000 units twice or thrice per day) thromboprophylaxis. We separately examined risk of escalation to therapeutic anticoagulation, severe disease (first occurrence of high-flow nasal cannula, noninvasive positive pressure ventilation or invasive mechanical ventilation), and death. To summarize risk, we present hazard ratios (HRs) with 95% confidence intervals (CIs) using adjusted time-dependent Cox proportional hazards regression models.

Results

People whose first dose was high intensity were younger, more often obese, and had greater oxygen support requirements. Intermediate dose thromboprophylaxis was associated with increased risk of therapeutic anticoagulation (HR, 3.39; 95% CI, 3.22-3.57), severe disease (HR, 1.22; 95% CI, 1.17-1.28), and death (HR, 1.37; 95% CI, 1.21-1.55). Increased risks associated with intermediate-dose thromboprophylaxis persisted in subgroup and sensitivity analyses varying populations and definitions of exposures, outcomes, and covariates.

Conclusions

Our findings do not support routine use of intermediate-dose thromboprophylaxis to prevent clinical worsening, severe disease, or death among adults hospitalized with COVID-19.

Enoxaparin Thromboprophylaxis in Children Hospitalized for COVID-19: A Phase 2 Trial

BACKGROUND

Evidence regarding the safety and efficacy of anticoagulant thromboprophylaxis among pediatric patients hospitalized for coronavirus disease 2019 (COVID-19) is limited. We sought to evaluate safety, dose-finding, and preliminary efficacy of twice-daily enoxaparin as primary thromboprophylaxis among children hospitalized for symptomatic COVID-19, including primary respiratory infection and multisystem inflammatory syndrome in children (MISC).

METHODS

We performed a phase 2, multicenter, prospective, open-label, single-arm clinical trial of twice-daily enoxaparin (initial dose: 0.5mg/kg per dose; max: 60mg; target anti-Xa activity: 0.20-0.49IU/mL) as primary thromboprophylaxis for children <18 years of age hospitalized for symptomatic COVID-19. Study endpoints included: cumulative incidence of International Society of Thrombosis and Haemostasis-defined clinically relevant bleeding; enoxaparin dose-requirements; and cumulative incidence of venous thromboembolism within 30-days of hospital discharge. Descriptive statistics summarized endpoint estimates that were further evaluated by participant age (±12 years) and clinical presentation.

RESULTS

Forty children were enrolled and 38 met analyses criteria. None experienced clinically relevant bleeding. Median (interquartile range) dose to achieve target anti-Xa levels was 0.5 mg/kg (0.48-0.54). Dose-requirement did not differ by age (0.5 [0.46-0.52] mg/kg for age ≥12 years versus 0.52 [0.49-0.55] mg/kg for age <12 years, P = .51) but was greater for participants with MISC (0.52 [0.5-0.61] mg/kg) as compared with primary COVID-19 (0.48 [0.39-0.51] mg/kg, P = .010). Two children (5.3%) developed central-venous catheter-related venous thromboembolism. No serious adverse events were related to trial intervention.

CONCLUSIONS

Among children hospitalized for COVID-19, thromboprophylaxis with twice-daily enoxaparin appears safe and warrants further investigation to assess efficacy.

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.

Biomarker derived risk scores predict venous thromboembolism and major bleeding among patients with COVID-19

Background

Venous thromboembolism (VTE) risk is increased in patients with COVID-19 infection. Understanding which patients are likely to develop VTE may inform pharmacologic VTE prophylaxis decision making. The hospital-associated venous thromboembolism-Intermountain Risk Score (HA-VTE IMRS) and the hospital-associated major bleeding-Intermountain Risk Score (HA-MB IMRS) are risk scores predictive of VTE and bleeding that were derived from only patient age and data found in the complete blood count (CBC) and basic metabolic panel (BMP).

Objectives

We assessed the HA-VTE IMRS and HA-MB IMRS for predictiveness of 90-day VTE and major bleeding, respectively, among patients diagnosed with COVID-19, and further investigated if adding D-dimer improved these predictions. We also reported 30-day outcomes.

Patients/Methods

We identified 5047 sequential patients with a laboratory confirmed diagnosis of COVID-19 and a CBC and BMP between 2 days before and 7 days following the diagnosis of COVID-19 from March 12, 2020, to February 28, 2021. We calculated the HA-VTE IMRS and the HA-MB IMRS for all patients. We assessed the added predictiveness of D-dimer obtained within 48 hours of the COVID test.

Results

The HA-VTE IMRS yielded a c-statistic of 0.70 for predicting 90-day VTE and adding D-dimer improved the c-statistic to 0.764 with the corollary sensitivity/specificity/positive/negative predictive values of 49.4%/75.7%/6.7%/97.7% and 58.8%/76.2%/10.9%/97.4%, respectively. Among hospitalized and ambulatory patients separately, the HA-VTE IMRS performed similarly. The HA-MB IMRS predictiveness for 90-day major bleeding yielded a c-statistic of 0.64.

Conclusion

The HA-VTE IMRS and HA-MB IMRS predict 90- and 30-day VTE and major bleeding among COVID-19 patients. Adding D-dimer improved the predictiveness of the HA-VTE IMRS for VTE.

Venous and Arterial Thrombosis in Ambulatory and Discharged COVID-19 Patients: A Systematic Review and Meta-analysis

Introduction  Venous and arterial thromboses are frequently observed complications in patients with severe novel coronavirus disease 2019 (COVID-19) infection who require hospital admission. In this study, we evaluate the epidemiology of venous and arterial thrombosis events in ambulatory and postdischarge patients with COVID-19 infection.

Materials and Method  EMBASE and MEDLINE were searched up to July 21, 2021, in addition to other sources. We included studies that assessed the epidemiology of venous and arterial thrombosis events in ambulatory and postdischarge COVID-19 patients.

Results  A total of 16 studies (102,779 patients) were identified. The overall proportion of venous thromboembolic events in all patients, that is, ambulatory and postdischarge, was 0.80% (95% confidence interval [CI]: 0.44–1.28), 0.28% (95% CI: 0.07–0.64), and 1.16% (95% CI: 0.69–1.74), respectively. Arterial events occurred in 0.75% (95% CI: 0.27–1.47) of all patients, 1.45% (95% CI: 1.10–1.86) of postdischarge patients, and 0.23% (95% CI: 0.019–0.66) of ambulatory patients. The pooled incidence rate estimates per 1,000 patient-days for VTE events were 0.06 (95% CI: 0.03–0.08) and 0.12 (95% CI: 0.07–0.19) for outpatients and postdischarge, respectively, whereas for arterial events were 0.10 (95% CI: 0–0.30) and 0.26 (95% CI: 0.16–0.37).

Conclusion  This study found a low risk of venous and arterial thrombi in ambulatory and postdischarge COVID-19 patients, with a higher risk in postdischarge patients compared with ambulatory patients. This suggests that regular universal thromboprophylaxis in these patient populations is probably not necessary.