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

Risk of recurrence after discontinuing anticoagulation in patients with COVID-19- associated venous thromboembolism: a prospective multicentre cohort study

Background

The clinical relevance of recurrent venous thromboembolism (VTE) after discontinuing anticoagulation in patients with COVID-19-associated VTE remains uncertain. We estimated the incidence rates and mortality of VTE recurrences developing after discontinuing anticoagulation in patients with COVID-19-associated VTE.

Methods

A prospective, multicenter, non-interventional study was conducted between March 25, 2020, and July 26, 2023, including patients who had discontinued anticoagulation after at least 3 months of therapy. All patients from the registry were analyzed during the study period to verify inclusion criteria. Patients with superficial vein thrombosis, those who did not receive at least 3 months of anticoagulant therapy, and those who were followed for less than 15 days after discontinuing anticoagulation were excluded. Outcomes were: 1) Incidence rates of symptomatic VTE recurrences, and 2) fatal PE. The rate of VTE recurrences was defined as the number of patients with recurrent VTE divided by the patient-years at risk of recurrent VTE during the period when anticoagulation was discontinued.

Findings

Among 1106 patients with COVID-19-associated VTE (age 62.3 ± 14.4 years; 62.9% male) followed-up for 12.5 months (p25-75, 6.3-20.1) after discontinuing anticoagulation, there were 38 VTE recurrences (3.5%, 95% confidence interval [CI]: 2.5-4.7%), with a rate of 3.1 per 100 patient-years (95% CI: 2.2-4.2). No patient died of recurrent PE (0%, 95% CI: 0-7.6%). Subgroup analyses showed that patients with diagnosis in 2021-2022 (vs. 2020) (Hazard ratio [HR] 2.86; 95% CI 1.45-5.68) or those with isolated deep vein thrombosis (vs. pulmonary embolism) (HR 2.31; 95% CI 1.19-4.49) had significantly higher rates of VTE recurrences.

Interpretation

In patients with COVID-19-associated VTE who discontinued anticoagulation after at least 3 months of treatment, the incidence rate of recurrent VTE and the case-fatality rate was low. Therefore, it conceivable that long-term anticoagulation may not be required for many patients with COVID-19-associated VTE, although further research is needed to confirm these findings.

Funding

Sanofi and Rovi, Sanofi Spain.

Congenital Bleeding Disorders and COVID-19-A Systematic Literature Review

Hypercoagulability is a prominent feature of coronavirus disease 2019 (COVID-19) and can lead to fatal consequences. Although the impact of COVID-19 on several disorders is well-established, its effect on congenital bleeding disorders (CBDs) is not well-documented. To address this ambiguity, a systematic review was conducted on the available studies to determine the impact of COVID-19 and vaccination aimed to prevent COVID-19 on patients with CBDs. We performed a systematic literature review using relevant keywords and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol. We conducted our search on the PubMed, Scopus, and Web of Science databases until July 2023. Out of 31 included studies, 12 case series covering 770 patients with CBD and COVID-19 were further analyzed. The majority of the patients had hemophilia A (n = 352, ∼46%) or hemophilia B (n = 74, ∼10%), while the remaining patients had von Willebrand disease (n = 43, 5.6%) or rare bleeding disorders (n = 27, 3.5%). A total of 25 deaths (3.2%) and 22 intensive care unit admissions (2.8%) were recorded. Bleeding complications were reported in the majority of the 12 case series (n = 7, 58.3%) and in most of the case reports (n = 8, ∼57%), while thrombotic complications were only reported in two studies (16.6%). The mortality rate ranged from 0% in five studies (41.6%) to 5.7% and the rate of hospitalization ranged from 0 to 40%. Bleeding complications were reported in a range of 0 to 81%, while the thrombotic complication rate in one study was 6.9%. The mortality rate varied from 0 to 5.7%, and the hospitalization rate ranged from 0 to 40%. Bleeding complications were reported in a range of 0 to 81%, while the rate of thrombotic complications in one study was 6.9%. Vaccination was reported in five case series, which included 821 patients with CBDs with the majority having hemophilia A (n = 479; 67.2%) and hemophilia B (n = 85; ∼12%). The most frequently reported side effects were myalgia (6.5%), flu-like symptoms (4.8%), fever (4.7%), and headache (4%). COVID-19 in patients with CBDs appears to provoke thrombotic complications and bleeding events more frequently, as well as a higher rate of hospitalization, which may be partially due to the increased risk of bleeding events. Although it seems that patients with CBD have lower mortality rates, further studies are necessary to fully understand this, especially considering comorbidities and low number of available studies.

An eco-friendly and cost-effective HPTLC method for quantification of COVID-19 antiviral drug and co-administered medications in spiked human plasma

The coronavirus-2 has led to a global pandemic of COVID-19 with an outbreak of severe acute respiratory syndrome leading to worldwide quarantine measures and a rise in death rates. The objective of this study is to propose a green, sensitive, and selective densitometric method to simultaneously quantify remdesivir (REM) in the presence of the co-administered drug linezolid (LNZ) and rivaroxaban (RIV) in spiked human plasma. TLC silica gel aluminum plates 60 F254 were used as the stationary phase, and the mobile phase was composed of dichloromethane (DCM): acetone (8.5:1.5, v/v) with densitometric detection at 254 nm. Well-resolved peaks have been observed with retardation factors (Rf) of 0.23, 0.53, and 0.72 for REM, LNZ, and RIV, respectively. A validation study was conducted according to ICH Q2 (R1) Guidelines. The method was rectilinear over the concentration ranges of 0.2-5.5 μg/band, 0.2-4.5 μg/band and 0.1-3.0 μg/band for REM, LNZ and RIV, respectively. The sensitivities of REM, LIN, and RIV were outstanding, with quantitation limits of 128.8, 50.5, and 55.8 ng/band, respectively. The approach has shown outstanding recoveries ranging from 98.3 to 101.2% when applied to pharmaceutical formulations and spiked human plasma. The method's greenness was assessed using Analytical Eco-scale, GAPI, and AGREE metrics.

Deregulated expression of autophagy genes; PIK3C3 and RAB7A in COVID-19 patients

BACKGROUND

The role of autophagy in coronaviruses infection and replication has a lot of debate. Autophagy involves the catalytic breakdown of intracellular components to be subsequently recycled by the lysosome. The aim of the study was to evaluate autophagy genes; PIK3C3 and RAB7A expressions in COVID-19 patients, and identify if PIK3C3 and RAB7A can be used as markers for monitoring COVID-19 patients.

METHODS

A case-control study was carried out on 50 patients and 50 healthy controls. Genes expression was performed using quantitative real-time polymerase chain reaction.

RESULTS

Compared to controls, PIK3C3 and RAB7A gene expression levels were significantly lower in patients (p < 0.001) with approximately with 9.4 and 2.3 decreased fold in PIK3C3 and RAB7A respectively. The ROC curve of PIK3C3 and RAB7A expressions showed sensitivity of 84 % and 74 % and specificity of 98 % and 78 % respectively. There was a positive correlation between PIK3C3 expression and WBCs, absolute neutrophil count, interleukin-6, D-dimer, and ALT among patients and between RAB7A expression and WBCs, CRP, IL-6, D-dimer and ALT in patients.

CONCLUSIONS

The study showed reduction of PIK3C3 and RAB7A expressions in COVID-19 patients. However, further studies are recommended to clarify their roles in the disease pathogenies as autophagy genes.

Antithrombotic Use Patterns in COVID-19 Patients from Spain: A Real-World Data Study

Antithrombotics have been widely used to treat and prevent COVID-19-related thrombosis; however, studies on their use at population levels are limited. We aimed to describe antithrombotic use patterns during the pandemic in Spanish primary care and hospital-admitted patients with COVID-19. Methods: A real-world data study was performed. Data were obtained from BIFAP's electronic health records. We investigated the antithrombotic prescriptions made within ±14 days after diagnosis between March 2020 and February 2022, divided their use into prior and new/naive groups, and reported their post-discharge use. Results: We included 882,540 individuals (53.4% women), of whom 78,499 were hospitalized. The median age was 44.7 (IQR 39-59). Antithrombotics were prescribed in 37,183 (4.6%) primary care subjects and 42,041 (53.6%) hospital-admitted patients, of whom 7505 (20.2%) and 20,300 (48.3%), respectively, were naive users. Prior users were older and had more comorbidities than new users. Enoxaparin was the most prescribed antithrombotic in hospitals, with higher prescription rates in new than prior users (2348.2, IQR 2390-3123.1 vs. 1378, IQR 1162-1751.6 prescriptions per 10,000 cases, p = 0.002). In primary care, acetylsalicylic acid was the most used antithrombotic, with higher use rates in prior than in naïve users. Post-discharge use occurred in 6686 (15.9%) subjects (median use = 10 days, IQR 9-30). Conclusions: Our study identified a consensus on prescribing antithrombotics in COVID-19 patients, but with low use rates in hospitals.

Effect of anticoagulation on the incidence of venous thromboembolism, major bleeding, and mortality among hospitalized COVID-19 patients: an updated meta-analysis

Objective

Anticoagulation is crucial for patients hospitalized with coronavirus disease 2019 (COVID-19) due to the high risk of venous thromboembolism (VTE). However, the optimal anticoagulation regimen needs further exploration. Therefore, we evaluated the efficacy and safety of diverse anticoagulation dosage dosages for COVID-19.

Methods

An updated meta-analysis was performed to assess the effect of thromboprophylaxis (standard, intermediate, and therapeutic dose) on the incidence of VTE, mortality and major bleeding among COVID-19 patients. Literature was searched via PubMed, EMBASE, Web of Science, and China National Knowledge Infrastructure (CNKI) database. The odds ratio (OR) and 95% confidence interval (CI) were calculated for effect estimates.

Results

Nineteen studies involving 25,289 participants without VTE history were included. The mean age of patients was 59.3 years old. About 50.96% were admitted to the intensive care unit. In the pooled analysis, both therapeutic-dose and intermediate-dose anticoagulation did not have a significant advantage in reducing VTE risk over standard dosage (OR = 1.09, 95% CI: 0.58-2.02, and OR = 0.89, 95% CI: 0.70-1.12, respectively). Similarly, all-cause mortality was not further decreased in either therapeutic-dose group (OR = 1.12, 95% CI: 0.75-1.67) or intermediate-dose group (OR = 1.34, 95% CI: 0.83-2.17). While the major bleeding risk was significantly elevated in the therapeutic-dose group (OR = 2.59, 95%CI: 1.87-3.57) as compared with the standard-dose regimen. Compared with intermediate dosage, therapeutic anticoagulation did not reduce consequent VTE risk (OR = 0.85, 95% CI: 0.52-1.38) and all-cause mortality (OR = 0.84, 95% CI: 0.60-1.17), but significantly increased major bleeding rate (OR = 2.42, 95% CI: 1.58-3.70). In subgroup analysis of patients older than 65 years, therapeutic anticoagulation significantly lowered the incidence of VTE in comparation comparison with standard thromboprophylaxis, however, at the cost of elevated risk of major bleeding.

Conclusion

Our results indicated that for most hospitalized patients with COVID-19, standard-dose prophylactic anticoagulation might be the optimal choice. For elderly patients at low risk of bleeding, therapeutic-dose anticoagulation could further reduce VTE risk and should be considered especially when there were other strong risk factors of VTE during hospital stay.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO, identifier, CRD42023388429.

Time Course of the Interaction Between Oral Short-Term Ritonavir Therapy with Three Factor Xa Inhibitors and the Activity of CYP2D6, CYP2C19, and CYP3A4 in Healthy Volunteers

BACKGROUND

We investigated the effect of a 5-day low-dose ritonavir therapy, as it is used in the treatment of COVID-19 with nirmatrelvir/ritonavir, on the pharmacokinetics of three factor Xa inhibitors (FXaI). Concurrently, the time course of the activities of the cytochromes P450 (CYP) 3A4, 2C19, and 2D6 was assessed.

METHODS

In an open-label, fixed sequence clinical trial, the effect and duration of a 5-day oral ritonavir (100 mg twice daily) treatment on the pharmacokinetics of three oral microdosed FXaI (rivaroxaban 25 µg, apixaban 25 µg, and edoxaban 50 µg) and microdosed probe drugs (midazolam 25 µg, yohimbine 50 µg, and omeprazole 100 µg) was evaluated in eight healthy volunteers. The plasma concentrations of all drugs were quantified using validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods and pharmacokinetics were analysed using non-compartmental analyses.

RESULTS

Ritonavir increased the exposure of apixaban, edoxaban, and rivaroxaban, but to a different extent the observed area under the plasma concentration-time curve (geometric mean ratio 1.29, 1.46, and 1.87, respectively). A strong CYP3A4 inhibition (geometric mean ratio > 10), a moderate CYP2C19 induction 2 days after ritonavir (0.64), and no alteration of CYP2D6 were observed. A CYP3A4 recovery half-life of 2.3 days was determined.

CONCLUSION

This trial with three microdosed FXaI suggests that at most the rivaroxaban dose should be reduced during short-term ritonavir, and only in patients receiving high maintenance doses. Thorough time series analyses demonstrated differential effects on three different drug-metabolising enzymes over time with immediate profound inhibition of CYP3A4 and only slow recovery after discontinuation.

CLINICAL TRIAL REGISTRATION

EudraCT number: 2021-006643-39.

COVID-19 and Long-COVID Thrombosis: From Clinical and Basic Science to Therapeutics

Coronavirus infectious disease-19 (COVID-19) is a pandemic characterized by serious lung disease and thrombotic events in the venous and circulation trees, which represent a harmful clinical sign of poor outcome. Thrombotic events are more frequent in patients with severe disease requiring intensive care units and are associated with platelet and clotting activation. However, after resolution of acute infection, patients may still have clinical sequelae, the so-called long-COVID-19, including thrombotic events again in the venous and arterial circulation. The mechanisms accounting for thrombosis in acute and long COVID-19 have not been fully clarified; interactions of COVID-19 with angiotensin converting enzyme 2 or toll-like receptor family or infection-induced cytokine storm have been suggested to be implicated in endothelial cells, leucocytes, and platelets to elicit clotting activation in acute as well in chronic phase of the disease. In acute COVID-19, prophylactic or full doses of anticoagulants exert beneficial effects even if the dosage choice is still under investigation; however, a residual risk still remains suggesting a need for a more appropriate therapeutic approach. In long COVID-19 preliminary data provided useful information in terms of antiplatelet treatment but definition of candidates for thrombotic prophylaxis is still undefined.

Thrombosis and Bleeding Risk Scores Are Strongly Associated with Mortality in Hospitalized Patients with COVID-19: A Multicenter Cohort Study

Background: Internationally established guidelines mention pharmacological prophylaxis for all hospitalized COVID-19 patients. However, there are concerns regarding the efficacy and safety of anticoagulants. This study investigated the associations between thrombosis/bleeding risk scores and clinical outcomes. Methods: We conducted a retrospective review of adult patients admitted to two hospitals between 2021 and 2022. We analyzed clinical data, laboratory results, low molecular weight heparin (LMWH) use, thrombosis, bleeding, and 30-day survival. Results: Of the 160 patients, 69.4% were female, and the median age was 59 years. The rates of thrombotic complications and mortality were 12.5% and 36.3%, respectively. LMWH prophylaxis was administered to 73 of the patients (45.6%). The patients with high Padua prediction scores (PPS) and high IMPROVEVTE scores had a significantly higher risk of venous thromboembolism (VTE) compared to those with low scores (30.8% vs. 9.0%, p = 0.006 and 25.6% vs. 7.7%, p = 0.006). Similarly, elevated IMPROVEVTE and IMPROVEBRS scores were associated with increased mortality (hazard ratios of 7.49 and 6.27, respectively; p < 0.001). Interestingly, LMWH use was not associated with a decreased incidence of VTE when stratified by risk groups. Conclusions: this study suggests that COVID-19 patients with high thrombosis and bleeding risk scores have a higher mortality rate.

The Burden of Cardiovascular Disease in the Post-COVID Era

In 2019, before the COVID-19 pandemic, cardiovascular disease (CVD) was the leading cause of death. Since 2020, the pandemic has had far-reaching effects on the landscape of health care including CVD prevention and management. Recent decreases in life expectancy in the United States could potentially be explained by issues related to disruptions in CVD prevention and control of CVD risk factors from the COVID-19 pandemic. This article reviews the effects of the SARS-CoV-2 virus and the accompanying pandemic on CVD risk factor prevention and management in the United States. Potential solutions are also proposed for these patients.

Improving Venous Thromboembolism Prophylaxis Through Service Integration, Policy Enhancement, and Health Informatics

Introduction

Venous thromboembolism (VTE) prevention and management are susceptible issues that require specific rules to sustain and oversee their functioning, as preventing VTE is a vital patient safety priority. This paper aims to investigate and provide recommendations for VTE assessment and reassessment through policy enhancement and development.

Methods

We reviewed different papers and policies to propose recommendations and theme analysis for policy modifications and enhancements to improve VTE prophylaxis and management.

Results

Recommendations were set to enhance the overall work of VTE prophylaxis, where the current VTE protocols and policies must ensure high levels of patient safety and satisfaction. The recommendations included working through a well-organized multidisciplinary team and staff engagement to support and enhance VTE's work. Nurses', pharmacists', and physical therapists' involvement in setting up the plan and prevention is the way to share the knowledge and paradigm of experience to standardize the management. Promoting policies regarding VTE prophylaxis assessment and reassessment using electronic modules as a part of the digital health process was proposed. A deep understanding of the underlying issues and the incorporation of generic policy recommendations were set.

Conclusion

This article presents recommendations for stakeholders, social media platforms, and healthcare practitioners to enhance VTE prophylaxis and management.

Comparison of clinical characteristics, hospital treatment and outcomes in all four waves of Covid-19 patients at RTEH Muzaffargarh, Pakistan

Background and Objective

The coronavirus pandemic followed a succession of COVID-19 waves globally, and had a varying pattern of frequency of cases and disease spectrum as each wave came with its distinct viral characteristics. The objective of this study was to compare clinical characteristics, treatments and outcomes of patients admitted with severe COVID -19 pneumonia in all four waves at Recep Tayyip Erdogan Hospital (RTEH).

Methods

A cross sectional retrospective study was conducted at the COVID unit of Recep Tayyip Erdogan Hospital (RTEH), Muzaffargarh, from April 2020 to December 2021. Retrospective data was taken from Electronic Medical Records of patients of Covid pneumonia and divided into four groups according to four waves of Covid pandemic. The main objective was to compare disease spectrum, treatments and outcomes of patients admitted with severe COVID-19 pneumonia in all four waves at RTEH. Demographic characteristics, inflammatory markers such as C reactive protein (CRP), serum lactate dehydrogenase (LDH), serum ferratin and absolute lymphocyte counts, mortality, length of hospital and ICU stay and event of mechanical ventilation were compared between groups. The Kolmogorov-Smirnov test was applied to check the normality. P-value <0.05 was considered significance.

Results

Of a total of 903 patients with covid pneumonia, 521(57.7%) were males and 382 (42.3%) females. Their mean age was 55.56±15.06 years. The mean length of stay (LOS) at the hospital was higher in first wave and least in fourth wave, 9.06±6.46 days and 6.56±5.34 days, respectively, (p<0.010). In first wave, LOS was generally >10 days with 21 (22.6%) while 33(26.8%) patients were shifted to ICU in first and second waves, respectively. Whereas, 35(8.2%) patients shifted to ICU in fourth wave (p<0.010). The use of mechanical ventilation was most common in first and second wave, 14 (15.1%) and 18 (14.6%), respectively. Mortality rate was highest in the third wave, 102 (38.9%, p<0.010) compared to the rest of the waves.

Conclusion

Comparison of COVID-19 pneumonia patients across pandemic waves has revealed dynamic trends in patient outcomes. The initial waves had higher ICU admissions and mortality rate, suggesting a need for improved early response and resource allocation. Continuous adaptability in healthcare strategies was paramount for enhancing patient care during the ever-changing pandemic landscape.

Pharmacogenomic Considerations for Anticoagulant Prescription in Patients with Hereditary Haemorrhagic Telangiectasia

Hereditary haemorrhagic telangiectasia (HHT) is a vascular dysplasia that commonly results in bleeding but with frequent indications for therapeutic anticoagulation. Our aims were to advance the understanding of drug-specific intolerance and evaluate if there was an indication for pharmacogenomic testing. Genes encoding proteins involved in the absorption, distribution, metabolism, and excretion of warfarin, heparin, and direct oral anticoagulants (DOACs) apixaban, rivaroxaban, edoxaban, and dabigatran were identified and examined. Linkage disequilibrium with HHT genes was excluded, before variants within these genes were examined following whole genome sequencing of general and HHT populations. The 44 genes identified included 5/17 actionable pharmacogenes with guidelines. The 76,156 participants in the Genome Aggregation Database v3.1.2 had 28,446 variants, including 9668 missense substitutions and 1076 predicted loss-of-function (frameshift, nonsense, and consensus splice site) variants, i.e., approximately 1 in 7.9 individuals had a missense substitution, and 1 in 71 had a loss-of-function variant. Focusing on the 17 genes relevant to usually preferred DOACs, similar variant profiles were identified in HHT patients. With HHT patients at particular risk of haemorrhage when undergoing anticoagulant treatment, we explore how pre-emptive pharmacogenomic testing, alongside HHT gene testing, may prove beneficial in reducing the risk of bleeding and conclude that HHT patients are well placed to be at the vanguard of personalised prescribing.

Venous thromboembolism prophylaxis practices for patients with sickle cell disease prior to and during the COVID-19 pandemic

Patients with sickle cell disease (SCD) are predisposed to a hypercoagulable state due to alterations in the coagulation system. Despite concern for the development of venous thromboembolism (VTE) in this population, there are no standardized guidelines for routine thromboprophylaxis. The objective of this study was to assess thromboprophylaxis practices of adult and pediatric treaters of SCD before and during the coronavirus disease of 2019 (COVID-19) pandemic. A cross-sectional electronic survey was distributed to pediatric and adult hematology oncology practitioners through seven SCD-specific interest groups between May 29, 2020, and July 13, 2020. Of 93 total responses, 14% ( N  = 13) reported they only treat patients more than 21 years old; 38.7% ( N  = 36) only treat patients 0-21 years old and 47.3% ( N  = 44) reported they treat both. Our study showed that before the COVID-19 pandemic, 96% of adult practitioners would recommend pharmacologic thromboprophylaxis, mechanical thromboprophylaxis or both for hospitalized adults with thromboprophylaxis, but only 76% of pediatric treaters would recommend any thromboprophylaxis in hospitalized children ( P  < 0.0001), with 24% of pediatric treaters choosing no thromboprophylaxis at all. During the COVID-19 pandemic, pharmacologic thromboprophylaxis specifically was recommended for adults by 94% of treaters and for pediatric patients by 76% of treaters. These findings suggest that despite the lack of evidence-based thromboprophylaxis guidelines in adults and children with thromboprophylaxis, subspecialty treaters routinely provide pharmacologic thromboprophylaxis in their adult patients and will modify their practice in pediatric patients who are considered at a high risk for VTE.

Diagnosis and treatment of coagulopathy using thromboelastography with platelet mapping is associated with decreased risk of pulmonary failure in COVID-19 patients

INTRODUCTION

Treatment of coronavirus disease 2019 (COVID-19) patients may require antithrombotic and/or anti-inflammatory medications. We hypothesized that individualized anticoagulant (AC) management, based on diagnosis of coagulopathy using thromboelastography with platelet mapping (TEG-PM), would decrease the frequency of pulmonary failure (PF) requiring mechanical ventilation (MV), mitigate thrombotic and hemorrhagic events, and, in-turn, reduce mortality.

METHODS

Hospital-admitted COVID-19 patients, age 18 or older, with escalating oxygen requirements were included. Prospective and supplemental retrospective chart reviews were conducted during a 2-month period. Patients were stratified into two groups based on clinician-administered AC treatment: TEG-PM guided vs. non-TEG guided.

RESULTS

Highly-elevated inflammatory markers (D-dimer, C-reactive protein, ferritin) were associated with poor prognosis but did not distinguish coagulopathic from noncoagulopathic patients. TEG-guided AC treatment was used in 145 patients vs. 227 treated without TEG-PM guidance. When managed by TEG-PM, patients had decreased frequency of PF requiring MV (45/145 [31%] vs. 152/227 [66.9%], P  < 0.0001), fewer thrombotic events (2[1.4%] vs. 39[17.2%], P  = 0.0019) and fewer hemorrhagic events (6[4.1%] vs. 24[10.7%], P  = 0.0240), and had markedly reduced mortality (43[29.7%] vs. 142[62.6%], P  < 0.0001). Platelet hyperactivity, indicating the need for antiplatelet medications, was identified in 75% of TEG-PM patients. When adjusted for confounders, empiric, indiscriminate AC treatment (not guided by TEG-PM) was shown to be an associated risk factor for PF requiring MV, while TEG-PM guided management was associated with a protective effect (odds ratio = 0.18, 95% confidence interval 0.08-0.4).

CONCLUSIONS

Following COVID-19 diagnosis, AC therapies based on diagnosis of coagulopathy using TEG-PM were associated with significantly less respiratory decompensation, fewer thrombotic and hemorrhagic complications, and improved likelihood of survival.

Longitudinal analysis of chest Q-SPECT/CT in patients with severe COVID-19

INTRODUCTION

Patients with COVID-19 have an increased risk for microvascular lung thrombosis. In order to evaluate the type and prevalence of perfusion defects, we performed a longitudinal analysis of combined perfusion single-photon emission and low-dose computed tomography (Q-SPECT/CT scan) in patients with COVID-19 pneumonia.

METHODS

Consecutive patients with severe COVID-19 (B.1.1.7 variant SARS-CoV-2) and respiratory insufficiency underwent chest Q-SPECT/CT during hospitalization, and 3 months after discharge. At follow-up (FU), Q-SPECT/CT were analyzed and compared with pulmonary function tests (PFT), blood analysis (CRP, D-dimers, ferritin), modified Medical Research Council (mMRC) dyspnea scale, and high-resolution CT scans (HRCT). Patients with one or more segmental perfusion defects outside the area of inflammation (PDOI) were treated with anticoagulation until FU.

RESULTS

At baseline, PDOI were found in 50 of 105 patients (47.6 %). At FU, Q-SPECT/CT scans had improved significantly (p < 0.001) and PDOI were recorded in 14 of 77 (18.2 %) patients. There was a significant correlation between mMRC score and the number of segmental perfusion defects (r = 0.511, p < 0.001), and a weaker correlation with DLCO (r = -0.333, p = 0.002) and KCO (r = -0.373, p = 0.001) at FU. Neither corticosteroid therapy nor HRCT results showed an influence on Q-SPECT/CT changes (p = 0.94, p = 0.74). CRP, D-Dimers and ferritin improved but did not show any association with the FU Q-SPECT/CT results (p = 0.08).

CONCLUSION

Segmental mismatched perfusion defects are common in severe COVID-19 and are correlated with the degree of dyspnea. Longitudinal analyses of Q-SPECT/CT scans in severe COVID-19 may help understand possible mechanisms of long COVID and prolonged dyspnea.

Edoxaban and/or colchicine in outpatients with COVID-19: rationale and design of the CONVINCE trial

BACKGROUND

An excessive inflammatory response and a hypercoagulable state are not infrequent in patients with coronavirus disease-2019 (COVID-19) and are associated with adverse clinical outcomes. However, the optimal treatment strategy for COVID-19 patients managed in the out-of-hospital setting is still uncertain.

DESIGN

The CONVINCE (NCT04516941) is an investigator-initiated, open-label, blinded-endpoint, 2 × 2 factorial design randomized trial aimed at assessing two independently tested hypotheses (anticoagulation and anti-inflammatory ones) in COVID-19 patients. Adult symptomatic patients (≥18 years of age) within 7 days from reverse transcription-PCR (RT-PCR) diagnosis of SARS-CoV-2 infection managed at home or in nursery settings were considered for eligibility. Eligible patients fulfilling all inclusion and no exclusion criteria were randomized to edoxaban versus no treatment (anticoagulation hypothesis) and colchicine versus no treatment (anti-inflammatory hypothesis) in a 1 : 1:1 : 1 ratio. The study had two co-primary endpoints (one for each randomization), including the composite of major vascular thrombotic events at 25 ± 3 days for the anticoagulation hypothesis and the composite of SARS-CoV-2 detection rates at 14 ± 3 days by RT-PCR or freedom from death or hospitalizations (anti-inflammatory hypothesis). Study endpoints will be adjudicated by a blinded Clinical Events Committee. With a final sample size of 420 patients, this study projects an 80% power for each of the two primary endpoints appraised separately.

CONCLUSION

The CONVINCE trial aims at determining whether targeting anticoagulation and/or anti-inflammatory pathways may confer benefit in COVID-19 patients managed in the out-of-hospital setting.

TRIAL REGISTRATION

ClinicalTrials.gov number, NCT04516941.

What is the Optimal Treatment Regimen of Low-MolecularWeight Heparin in Coronavirus Disease 2019 Pneumonia?

OBJECTIVE

The optimal anticoagulant treatment regimen in hospitalized coronavirus disease 2019 (COVID-19) patients is uncertain. This study aimed to compare the rates of disease progression and mortality in patients treated with low-molecular-weight heparin (LMWH) according to baseline d-dimer levels and in those who received a fixed-dose regimen irrespective of the d-dimer level.

MATERIAL AND METHODS

This was a retrospective analysis of all patients admitted to a university hospital for COVID-19 pneumonia during a 1-year period. The protocol for d-dimer-driven therapy (on-protocol) was as follows: prophylactic dose when the baseline level is <1000 ng/mL, intermediate dose when the level is between 1000 and 3000 ng/mL, and therapeutic dose when the level is >3000 ng/mL. We compared the progression and mortality rates between the on-protocol and off-protocol treatment groups. The offprotocol group consisted of patients that received a fixed-dose LMWH regimen, which was not in accordance with the defined protocol.

RESULTS

Of 384 patients (mean age 61.5 ± 15.9 years, 216 male), 294 patients with complete data composed the study group, and 174 patients were treated on-protocol and 120 patients were treated off-protocol. The on-protocol group had lower C-reactive protein (CRP), ferritin, lactate dehydrogenase (LDH), and d-dimer levels and higher SpO2/FiO2 levels at admission. Disease progression developed in 45/174 on-protocol patients (25.9%) vs. 53/120 off-protocol patients (44.2%) during the follow-up (P = .001), and mortality was 29 (16.7%) vs. 32 (26.7%), respectively (P = .041). Logistic regression analysis was performed and included age, presence of comorbidities, LMWH regimen, baseline SpO2/FiO2, CRP, and LDH levels as independent variables. The presence of cardiac comorbidity, age, CRP, and LDH levels, but not the LMWH treatment regimen, were associated with both disease progression and mortality.

CONCLUSION

A d-dimer-driven LMWH treatment protocol is not associated with better clinical outcomes in hospitalized COVID-19 patients.

Incidence and Risk Factors Associated with Thromboembolic Events among Patients with COVID-19 Inpatients: A Retrospective Study

Aims and objectives

Despite thromboprophylaxis, some severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) patients develop thrombotic complications with poor prognosis. Our goal is to comprehensively assess the incidence, risk factors, and clinical outcomes associated with thromboembolic events (TE) among adult patients presenting with coronavirus disease-2019 (COVID-19).

Materials and methods

The study was conducted as an observational and retrospective study across COVID-19 patients (n = 207) in a tertiary care hospital in the Middle East and North Africa (MENA) region. Electronic health records were collected from the COVID-19 Database from April 2020 to December 2020 which included clinical history and TE.

Results

Fifty-six (27.05%) out of 207 patients (age: 54.42 ± 15.01 years) developed TE despite the anticoagulant therapy. The incidence of venous thromboembolism (VTE) was significantly higher for patients aged >50 years compared to <50 years (73.21% vs 26.79%, p < 0.05). There were no differences in the incidence of VTE between genders (p = 0.561). 165 patients (79.71%) received anticoagulant therapy, yet 48 (29%) developed TE. The most commonly used anticoagulant was low-molecular-weight heparin (LMWH, 47.34%). In spite of efficient treatment and medical management, the majority of patients with TE (45 out of 56 patients, 80.35%) experienced mortality. The comorbidities that significantly increase the risk of TE include hypertension (HTN) and ischemic heart disease (IHD). The laboratory parameters that were associated with an increased risk of VTE include ferritin, lactate dehydrogenase (LDH), and creatinine.

Conclusion

The COVID-19 patients develop thrombotic complications. Future studies should clarify the underlying mechanisms of TE and optimize the antithrombotic regimens in COVID-19 patients.

How to cite this article

Tashkandi WA. Incidence and Risk Factors Associated with Thromboembolic Events among Patients with COVID-19 Inpatients: A Retrospective Study. Indian J Crit Care Med 2023;27(11):830-836.

Endothelium dysfunction and thrombosis in COVID-19 with type 2 diabetes

SARS-CoV-2 can directly or indirectly damage endothelial cells. Endothelial injury, especially phosphatidylserine (PS) exposure on the outer membrane of cells, can more easily promote thrombosis. Type 2 diabetes(T2D) patients were more susceptible to COVID-19, they had more severe symptoms, higher risk of thrombotic complications, and longer duration of post-COVID-19 sequelae. This review provided a detailed overview of the mechanisms underlying endothelial dysfunction in T2D patients with COVID-19 (including long COVID), which may be influenced by hyperglycemia, hypoxia, and pro-inflammatory environments. The mechanisms of thrombosis in T2D patients with COVID-19 are also explored, particularly the effects of increased numbers of PS-exposing particles, blood cells, and endothelial cells on hypercoagulability. Given the high risk of thrombosis in T2D patients with COVID-19, early antithrombotic therapy can both minimize the impact of the disease on patients and maximize the chances of improvement, thereby alleviating patient suffering. We provided detailed guidance on antithrombotic drugs and dosages for mild, moderate, and severe patients, emphasizing that the optimal timing of thromboprophylaxis is a critical factor in influencing prognosis. Considering the potential interactions between antidiabetic, anticoagulant, and antiviral drugs, we proposed practical and comprehensive management recommendations to supplement the incomplete efficacy of vaccines in the diabetic population, reduce the incidence of post-COVID-19 sequelae, and improve patient quality of life.

A neutralizable dimeric anti-thrombin aptamer with potent anticoagulant activity in mice

Heparin-induced thrombocytopenia (HIT) is a complication caused by administration of the anticoagulant heparin. Although the number of patients with HIT has drastically increased because of coronavirus disease 2019 (COVID-19), the currently used thrombin inhibitors for HIT therapy do not have antidotes to arrest the severe bleeding that occurs as a side effect; therefore, establishment of safer treatments for HIT patients is imperative. Here, we devised a potent thrombin inhibitor based on bivalent aptamers with a higher safety profile via combination with the antidote. Using an anti-thrombin DNA aptamer M08s-1 as a promising anticoagulant, its homodimer and heterodimer with TBA29 linked by a conformationally flexible linker or a rigid duplex linker were designed. The dimerized M08s-1-based aptamers had about 100-fold increased binding affinity to human and mouse thrombin compared with the monomer counterparts. Administration of these bivalent aptamers into mice revealed that the anticoagulant activity of the dimers significantly surpassed that of an approved drug for HIT treatment, argatroban. Moreover, adding protamine sulfate as an antidote against the most potent bivalent aptamer completely suppressed the anticoagulant activity of the dimer. Emerging potent and neutralizable anticoagulant aptamers will be promising candidates for HIT treatment with a higher safety profile.

Anticoagulant therapy in COVID-19: A narrative review

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can manifest itself in several ways, including coagulopathy and thrombosis. These complications can be the first and sometimes only manifestations of SARS-CoV-2 infection and can occur early or late in the course of the disease. However, these symptoms are more prevalent in hospitalized patients with venous thromboembolism, particularly those admitted to intensive care units. Moreover, various forms of arterial and venous thrombosis, or micro- or macro-vasculature embolisms, have been reported during the current pandemic. They have led to harmful consequences, such as neurological and cardiac events, nearly all resulting from the hypercoagulable state caused by this viral infection. The severe hypercoagulability observed in patients with COVID-19 accounts for most cases of the disease that become critical. Therefore, anticoagulants seem to be one of the most vital therapeutics for treating this potentially life-threatening condition. In the current paper, we present a thorough review of the pathophysiology of COVID-19-induced hypercoagulable state and the use of anticoagulants to treat SARS-CoV-2 infections in different patient groups, as well as their pros and cons.

Thromboembolic Presentations among Patients Hospitalized to the Intensive Care Unit for Coronavirus Disease 2019 (COVID-19) - A Northern Taiwan Single Center Experience

Coronavirus Disease 2019 (COVID-19) has been associated with a high thromboembolic risk among patients in intensive care units. Asian populations may share a similar thromboembolic risk, but with a higher prevalence of arterial thromboembolism than venous thromboembolism. To clarify this risk in Taiwan, this single-center retrospective study collected 27 consecutive intensive care unit patients with COVID-19 confirmed by polymerase chain reaction, with a median age of 67.6 years (male 81.5%). Twenty-three patients received prophylactic anticoagulation (85.2%), and there were four bleeding events (14.8%). Nine patients had thromboembolism (33.3%), including three with deep vein thrombosis, two with peripheral artery thromboembolism, and four with ischemic stroke. There were no significant clinical differences between the patients with or without thromboembolism. Initial serum ferritin [adjusted odds ratio (OR): 13.19, 95% confidence interval (CI): 1.01-172.07] and peak serum procalcitonin (adjusted OR: 18.93, 95% CI: 1.08-330.91) were associated with a higher risk of thromboembolism. Furthermore, prophylactic anticoagulation (adjusted OR: 0.01, 95% CI: < 0.001-0.55) was associated with a lower risk of thromboembolism. All cases of deep vein thrombosis and one peripheral artery thromboembolism occurred at intravascular catheter locations. No association between thromboembolism and survival was found (age-adjusted hazard ratio: 0.55, 95% CI: 0.10-2.95). In conclusion, the prevalence of COVID-19 thromboembolism among Taiwanese patients in intensive care units was high, even with prophylactic anticoagulation. Serum ferritin and procalcitonin may identify high-risk populations. Prophylactic anticoagulation may reduce the risk of thromboembolism with a manageable bleeding risk. Larger prospective studies are needed to clarify the risk of COVID-19 thromboembolism and its risk factors in the post-Omicron era.

COVID-19 and cardiovascular complications: updates of emergency medicine

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and SARS-CoV-2 variants, has become a global pandemic resulting in significant morbidity and mortality. Severe cases of COVID-19 are characterized by hypoxemia, hyper-inflammation, cytokine storm in lung. Clinical studies have reported an association between COVID-19 and cardiovascular disease (CVD). Patients with CVD tend to develop severe symptoms and mortality if contracted COVID-19 with further elevations of cardiac injury biomarkers. Furthermore, COVID-19 itself can induce and promoted CVD development, including myocarditis, arrhythmia, acute coronary syndrome, cardiogenic shock, and venous thromboembolism. Although the direct etiology of SARS-CoV-2 induced cardiac injury remains unknown and under-investigated, it is suspected that it is related to myocarditis, cytokine-mediated injury, microvascular injury, and stress-related cardiomyopathy. Despite vaccinations having provided the most effective approach to reducing mortality overall, an adapted treatment paradigm and regular monitoring of cardiac injury biomarkers is critical for improving outcomes in vulnerable populations at risk for severe COVID-19. In this review, we focus on the latest progress in clinic and research on the cardiovascular complications of COVID-19 and provide a perspective of treating cardiac complications deriving from COVID-19 in Emergency Medicine.

A systematic review on post-discharge venous thromboembolism prophylaxis in patients with COVID-19

BACKGROUND

Coronavirus disease of 2019 (COVID-19) is associated with venous thromboembolism (VTE), not only during hospitalization but also after discharge, raising concerns about anticoagulant (AC) use for post-discharge COVID-19 patients. We aimed to systematically review the current literature on the possible benefits or risks regarding extended thromboprophylaxis.

MAIN BODY

We searched related databases from December 1, 2019, to October 6, 2022, including studies on the necessity, duration, and selection of the ideal AC regarding extended thromboprophylaxis for post-discharge COVID-19 patients. The screening of the selected databases led to 18 studies and 19 reviews and guidelines. Studies included 52,927 hospitalized COVID-19 patients, with 19.25% receiving extended thromboprophylaxis. VTE events ranging from 0 to 8.19% (median of 0.7%) occurred in a median follow-up of 49.5 days. All included studies and guidelines, except four studies, recommended post-discharge prophylaxis after an individual risk assessment indicating high thrombotic and low bleeding risk. Studies used risk assessment models (RAMs), clinical evaluation, and laboratory data to identify COVID-19 patients with a high risk of VTE. IMPROVE-DD was the most recommended RAM. Direct oral anticoagulants (DOACs) and low molecular weight heparins (LMWHs) were the most used AC classes.

CONCLUSIONS

Post-discharge prophylaxis for COVID-19 patients is recommended after an individual assessment. The IMPROVE-DD model can help predict VTE risk. After distinguishing patients who need post-discharge AC therapy, DOACs for 30-35 days and LMWHs for 40-45 days can be the drug of choice. Further studies, particularly the results of the ongoing randomized controlled trials (RCTs), are required. Also, to properly handle such patients, every physician should consider lifestyle modification in addition to pharmacological treatment for post-discharge VTE prophylaxis.

Prophylactic anticoagulants for non-hospitalised people with COVID-19

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has impacted healthcare systems worldwide. Multiple reports on thromboembolic complications related to COVID-19 have been published, and researchers have described that people with COVID-19 are at high risk for developing venous thromboembolism (VTE). Anticoagulants have been used as pharmacological interventions to prevent arterial and venous thrombosis, and their use in the outpatient setting could potentially reduce the prevalence of vascular thrombosis and associated mortality in people with COVID-19. However, even lower doses used for a prophylactic purpose may result in adverse events such as bleeding. It is important to consider the evidence for anticoagulant use in non-hospitalised people with COVID-19.

OBJECTIVES

To evaluate the benefits and harms of prophylactic anticoagulants versus active comparators, placebo or no intervention, or non-pharmacological interventions in non-hospitalised people with COVID-19.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 18 April 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing prophylactic anticoagulants with placebo or no treatment, another active comparator, or non-pharmacological interventions in non-hospitalised people with COVID-19. We included studies that compared anticoagulants with a different dose of the same anticoagulant. We excluded studies with a duration of under two weeks.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. Our primary outcomes were all-cause mortality, VTE (deep vein thrombosis (DVT) or pulmonary embolism (PE)), and major bleeding. Our secondary outcomes were DVT, PE, need for hospitalisation, minor bleeding, adverse events, and quality of life. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included five RCTs with up to 90 days of follow-up (short term). Data were available for meta-analysis from 1777 participants. Anticoagulant compared to placebo or no treatment Five studies compared anticoagulants with placebo or no treatment and provided data for three of our outcomes of interest (all-cause mortality, major bleeding, and adverse events). The evidence suggests that prophylactic anticoagulants may lead to little or no difference in all-cause mortality (risk ratio (RR) 0.36, 95% confidence interval (CI) 0.04 to 3.61; 5 studies; 1777 participants; low-certainty evidence) and probably reduce VTE from 3% in the placebo group to 1% in the anticoagulant group (RR 0.36, 95% CI 0.16 to 0.85; 4 studies; 1259 participants; number needed to treat for an additional beneficial outcome (NNTB) = 50; moderate-certainty evidence). There may be little to no difference in major bleeding (RR 0.36, 95% CI 0.01 to 8.78; 5 studies; 1777 participants; low-certainty evidence). Anticoagulants probably result in little or no difference in DVT (RR 1.02, 95% CI 0.30 to 3.46; 3 studies; 1009 participants; moderate-certainty evidence), but probably reduce the risk of PE from 2.7% in the placebo group to 0.7% in the anticoagulant group (RR 0.25, 95% CI 0.08 to 0.79; 3 studies; 1009 participants; NNTB 50; moderate-certainty evidence). Anticoagulants probably lead to little or no difference in reducing hospitalisation (RR 1.01, 95% CI 0.59 to 1.75; 4 studies; 1459 participants; moderate-certainty evidence) and may lead to little or no difference in adverse events (minor bleeding, RR 2.46, 95% CI 0.90 to 6.72; 5 studies, 1777 participants; low-certainty evidence). Anticoagulant compared to a different dose of the same anticoagulant One study compared anticoagulant (higher-dose apixaban) with a different (standard) dose of the same anticoagulant and reported five relevant outcomes. No cases of all-cause mortality, VTE, or major bleeding occurred in either group during the 45-day follow-up (moderate-certainty evidence). Higher-dose apixaban compared to standard-dose apixaban may lead to little or no difference in reducing the need for hospitalisation (RR 1.89, 95% CI 0.17 to 20.58; 1 study; 278 participants; low-certainty evidence) or in the number of adverse events (minor bleeding, RR 0.47, 95% CI 0.09 to 2.54; 1 study; 278 participants; low-certainty evidence). Anticoagulant compared to antiplatelet agent One study compared anticoagulant (apixaban) with antiplatelet agent (aspirin) and reported five relevant outcomes. No cases of all-cause mortality or major bleeding occurred during the 45-day follow-up (moderate-certainty evidence). Apixaban may lead to little or no difference in VTE (RR 0.36, 95% CI 0.01 to 8.65; 1 study; 279 participants; low-certainty evidence), need for hospitalisation (RR 3.20, 95% CI 0.13 to 77.85; 1 study; 279 participants; low-certainty evidence), or adverse events (minor bleeding, RR 2.13, 95% CI 0.40 to 11.46; 1 study; 279 participants; low-certainty evidence). No included studies reported on quality of life or investigated anticoagulants compared to a different anticoagulant, or anticoagulants compared to non-pharmacological interventions.

AUTHORS' CONCLUSIONS

We found low- to moderate-certainty evidence from five RCTs that prophylactic anticoagulants result in little or no difference in major bleeding, DVT, need for hospitalisation, or adverse events when compared with placebo or no treatment in non-hospitalised people with COVID-19. Low-certainty evidence indicates that prophylactic anticoagulants may result in little or no difference in all-cause mortality when compared with placebo or no treatment, but moderate-certainty evidence indicates that prophylactic anticoagulants probably reduce the incidence of VTE and PE. Low-certainty evidence suggests that comparing different doses of the same prophylactic anticoagulant may result in little or no difference in need for hospitalisation or adverse events. Prophylactic anticoagulants may result in little or no difference in risk of VTE, hospitalisation, or adverse events when compared with antiplatelet agents (low-certainty evidence). Given that there were only short-term data from one study, these results should be interpreted with caution. Additional trials of sufficient duration are needed to clearly determine any effect on clinical outcomes.

Role of Endothelium in Cardiovascular Sequelae of Long COVID

The global action against coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 infection, shed light on endothelial dysfunction. Although SARS-CoV-2 primarily affects the pulmonary system, multiple studies have documented pan-vascular involvement in COVID-19. The virus is able to penetrate the endothelial barrier, damaging it directly or indirectly and causing endotheliitis and multi-organ injury. Several mechanisms cooperate to development of endothelial dysfunction, including endothelial cell injury and pyroptosis, hyperinflammation and cytokine storm syndrome, oxidative stress and reduced nitric oxide bioavailability, glycocalyx disruption, hypercoagulability, and thrombosis. After acute-phase infection, some patients reported signs and symptoms of a systemic disorder known as long COVID, in which a broad range of cardiovascular (CV) disorders emerged. To date, the exact pathophysiology of long COVID remains unclear: in addition to the persistence of acute-phase infection mechanisms, specific pathways of CV damage have been postulated, such as persistent viral reservoirs in the heart or an autoimmune response to cardiac antigens through molecular mimicry. The aim of this review is to provide an overview of the main molecular patterns of enduring endothelial activation following SARS-CoV-2 infection and to offer the latest summary of CV complications in long COVID.

Use of Off-Label Drugs in COVID-19: Clinicians' Perceptions Based on a Cross-Sectional Observational Study

Introduction The absence of a common National Treatment Guideline during the second wave of the COVID-19 pandemic in India resulted in different treatment strategies, and the use of "off-label drugs" (OfLDs) was one of them. Aims This study aimed to assess the proportion of doctors who prescribed OfLDs, their perceived appropriateness, and the factors leading to their use. Settings and design This is an undergraduate student research project, in which a web-based cross-sectional survey was conducted on doctors who delivered care to COVID-19 patients during the second wave of the pandemic in Uttarakhand, India. Materials and methods The minimum sample size was 370 (for a 95% confidence level, an alpha error of 0.5, and a power of 80%). Data were collected electronically using a validated questionnaire after institutional ethical clearance and the participants' consent. Statistical analysis This is a descriptive-analytical study. Results We received 419 completed responses; all specialties had seen COVID-19 patients, and 91.4% (383) of the doctors had provided care to COVID-19 patients in some way or the other. About 90.7% (380) of the doctors used OfLDs; 62.5% (262) agreed that OfLDs were beneficial, and 78.9% (331) disagreed on universal steroid use. Only 34.1% (143) felt that using OfLDs was ethical. About 16.9% (71) of the doctors believed that alternative medicine was a useful treatment adjunct, and 20% (84) of doctors prescribed OfLDs under duress. About 21.2% (89) believed that Remdesivir was the main treatment for the disease, and 18.6% (78) believed that Tocilizumab was the main treatment for the disease. Personal experience, conviction, or advice from peers were among the various reasons that were put forward for using OfLDs. Conclusions The use of OfLDs during the COVID-19 pandemic in India was extensive. It was done sometimes under pressure and was largely based on confusion (multiplicity of guidelines, many times at variance with each other) as well as on a personal or low level of scientific evidence forwarded to support the use.

Increased Thrombotic Risk in COVID-19: Evidence and Controversy

The pandemic of respiratory disease caused by the novel coronavirus named SARS-CoV-2, which emerged at the end of 2019, is still ongoing [...].

Analysis of Ischemia-Modified Albumin (IMA) and Coagulation Parameters in Patients with SARS-CoV-2 Pneumonia

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a systemic disease which causes an increased inclination to thrombosis by leading to coagulation system activation and endothelial dysfunction. Our objective in this study is to determine whether ischemia-modified albumin (IMA) can be used as a new marker in patients with COVID-19 for evaluating the increased coagulation risk, pneumonic infiltration, and thus, prognosis.

METHODS

Our study included 59 patients with COVID-19 compatible pneumonic infiltration on lung computed tomography (CT) who applied to and were hospitalized in the Internal Diseases Outpatient Clinic, then followed up and treated, as well as 29 healthy individuals with a negative COVID-19 rRT-PCR test without any additional disease. Hemogram, coagulation, routine biochemistry, and serum IMA activity parameters were studied.

RESULTS

In our study, the higher serum IMA level in COVID-19 patients with pneumonic infiltration compared to that of the healthy control group was found to be statistically significant. No significant correlation was found between the serum IMA levels and the coagulation and inflammation parameters in the 59 COVID-19 patients included.

CONCLUSIONS

Serum IMA levels in COVID-19 patients with pneumonic infiltration on CT were found to be higher than in the control group. Examination of biochemical parameters, especially thrombotic parameters that affect prognosis such as IMA, can be a guide in estimating pneumonic infiltration.

Clinical characteristics of COVID-19 associated vasculopathic diseases

Coronavirus disease 19 (COVID-19) has shown to be an infectious disease affecting not only of the respiratory system, but also cardiovascular system leading to different COVID-19-associated vasculopathies. Venous and arterial thromboembolic events have been frequently described among hospitalized patients with COVID-19 and inflammatory vasculopathic changes have also been observed. Several of the reported COVID-19 associated vasculopathies exhibit differences on epidemiology, clinical characteristics and outcome compared to non-COVID-19 types. This review focuses on the epidemiology, clinical, diagnostic and therapeutic characteristics as well as outcome data of COVID-19 associated thromboembolic events and inflammatory vasculopathies, elaborating similarities and differences with non-COVID-19 cohorts.

Interrelationship between COVID-19 and Coagulopathy: Pathophysiological and Clinical Evidence

Since the first description of COVID-19 infection, among clinical manifestations of the disease, including fever, dyspnea, cough, and fatigue, it was observed a high incidence of thromboembolic events potentially evolving towards acute respiratory distress syndrome (ARDS) and COVID-19-associated-coagulopathy (CAC). The hypercoagulation state is based on an interaction between thrombosis and inflammation. The so-called CAC represents a key aspect in the genesis of organ damage from SARS-CoV-2. The prothrombotic status of COVID-19 can be explained by the increase in coagulation levels of D-dimer, lymphocytes, fibrinogen, interleukin 6 (IL-6), and prothrombin time. Several mechanisms have been hypothesized to explain this hypercoagulable process such as inflammatory cytokine storm, platelet activation, endothelial dysfunction, and stasis for a long time. The purpose of this narrative review is to provide an overview of the current knowledge on the pathogenic mechanisms of coagulopathy that may characterize COVID-19 infection and inform on new areas of research. New vascular therapeutic strategies are also reviewed.

Cell-Specific Mechanisms in the Heart of COVID-19 Patients

From the onset of the pandemic, evidence of cardiac involvement in acute COVID-19 abounded. Cardiac presentations ranged from arrhythmias to ischemia, myopericarditis/myocarditis, ventricular dysfunction to acute heart failure, and even cardiogenic shock. Elevated serum cardiac troponin levels were prevalent among hospitalized patients with COVID-19; the higher the magnitude of troponin elevation, the greater the COVID-19 illness severity and in-hospital death risk. Whether these consequences were due to direct SARS-CoV-2 infection of cardiac cells or secondary to inflammatory responses steered early cardiac autopsy studies. SARS-CoV-2 was reportedly detected in endothelial cells, cardiac myocytes, and within the extracellular space. However, findings were inconsistent and different methodologies had their limitations. Initial autopsy reports suggested that SARS-CoV-2 myocarditis was common, setting off studies to find and phenotype inflammatory infiltrates in the heart. Nonetheless, subsequent studies rarely detected myocarditis. Microthrombi, cardiomyocyte necrosis, and inflammatory infiltrates without cardiomyocyte damage were much more common. In vitro and ex vivo experimental platforms have assessed the cellular tropism of SARS-CoV-2 and elucidated mechanisms of viral entry into and replication within cardiac cells. Data point to pericytes as the primary target of SARS-CoV-2 in the heart. Infection of pericytes can account for the observed pericyte and endothelial cell death, innate immune response, and immunothrombosis commonly observed in COVID-19 hearts. These processes are bidirectional and synergistic, rendering a definitive order of events elusive. Single-cell/nucleus analyses of COVID-19 myocardial tissue and isolated cardiac cells have provided granular data about the cellular composition and cell type-specific transcriptomic signatures of COVID-19 and microthrombi-positive COVID-19 hearts. Still, much remains unknown and more in vivo studies are needed. This review seeks to provide an overview of the current understanding of COVID-19 cardiac pathophysiology. Cell type-specific mechanisms and the studies that provided such insights will be highlighted. Given the unprecedented pace of COVID-19 research, more mechanistic details are sure to emerge since the writing of this review. Importantly, our current knowledge offers significant clues about the cardiac pathophysiology of long COVID-19, the increased postrecovery risk of cardiac events, and thus, the future landscape of cardiovascular disease.

Venous thromboembolism secondary to hospitalization for COVID-19: patient management and long-term outcomes

Background

Venous thromboembolism (VTE) is a complication of COVID-19 in hospitalized patients. Little information is available on long-term outcomes of VTE in this population.

Objectives

We aimed to compare the characteristics, management strategies, and long-term clinical outcomes between patients with COVID-19-associated VTE and patients with VTE provoked by hospitalization for other acute medical illnesses.

Methods

This is an observational cohort study, with a prospective cohort of 278 patients with COVID-19-associated VTE enrolled between 2020 and 2021 and a comparison cohort of 300 patients without COVID-19 enrolled in the ongoing START2-Register between 2018 and 2020. Exclusion criteria included age <18 years, other indications to anticoagulant treatment, active cancer, recent (<3 months) major surgery, trauma, pregnancy, and participation in interventional studies. All patients were followed up for a minimum of 12 months after treatment discontinuation. Primary end point was the occurrence of venous and arterial thrombotic events.

Results

Patients with VTE secondary to COVID-19 had more frequent pulmonary embolism without deep vein thrombosis than controls (83.1% vs 46.2%, P <.001), lower prevalence of chronic inflammatory disease (1.4% and 16.3%, P <.001), and history of VTE (5.0% and 19.0%, P <.001). The median duration of anticoagulant treatment (194 and 225 days, P = 0.9) and the proportion of patients who discontinued anticoagulation (78.0% and 75.0%, P = 0.4) were similar between the 2 groups. Thrombotic event rates after discontinuation were 1.5 and 2.6 per 100 patient-years, respectively (P = 0.4).

Conclusion

The risk of recurrent thrombotic events in patients with COVID-19-associated VTE is low and similar to the risk observed in patients with VTE secondary to hospitalization for other medical diseases.

Effectiveness and Safety of Enoxaparin Versus Unfractionated Heparin as Thromboprophylaxis in Hospitalized COVID-19 Patients: Real-World Evidence

BACKGROUND

Coronavirus 2019 (COVID-19) patients are at risk of thrombosis. Literature that compares the effectiveness of enoxaparin to unfractionated heparin (UFH) in COVID-19 patients is scarce.

OBJECTIVE

We aimed to evaluate the effectiveness and safety of enoxaparin compared with UFH when used at their standard/intermediate dosing in COVID-19 patients.

METHODS

This was a retrospective study conducted at a large COVID-19 center located in Eastern Province, Saudi Arabia. Confirmed COVID-19 cases (≥18 years old) admitted between January and December 2020 were randomly screened for inclusion. Exclusion criteria were patients receiving therapeutic anticoagulation, on chronic anticoagulation, had active bleeding, a platelet count <25 × 109/L, or an incomplete electronic file. The primary endpoint was the occurrence of any thrombotic event (pulmonary embolism, deep venous thrombosis, stroke, or myocardial infarction) or mortality. Secondary endpoints were major or minor bleeding. We applied inverse propensity score weighting (IPTW) with survival analysis to analyze the primary endpoint. Logistic regression was used for the secondary endpoint.

RESULTS

A total of 980 patients were included (enoxaparin, n = 470 and UFH, n = 510) with a mean age (±SD) of 47.7 (± 12.3) for the enoxaparin arm and 52 (±13.9) for the UFH arm. There was a statistically significant difference in the primary endpoint with an adjusted hazard ratio (aHR) of 0.46 (95%CI: 0.22 to 0.96, P = 0.039) in favor of the enoxaparin arm. There was no statistically significant difference in major or minor bleeding rates between the two arms.

CONCLUSION AND RELEVANCE

When compared with UFH, enoxaparin was associated with a significant reduction in thrombotic events or mortality among COVID-19 patients. The results need confirmation from randomized controlled trials.

Multi-marker risk assessment in patients hospitalized with COVID-19: Results from the American Heart Association COVID-19 Cardiovascular Disease Registry

BACKGROUND

The pathobiology of inflammation, thrombosis, and myocardial injury associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) may be assessed by circulating biomarkers. However, their relative prognostic importance has been incompletely described.

METHODS

We analyzed data from patients hospitalized with COVID-19 from January 2020, to April 2021, at 122 US hospitals in the American Heart Association (AHA) COVID-19 cardiovascular (CV) disease registry. Patients with data for D-dimer, C-reactive protein (CRP), ferritin, natriuretic peptides [NP], or cardiac troponin (cTn) at admission were included. cTn quintiles were indexed to the assay-specific 99th percentile reference limits. Using multivariable logistic regression, we assessed the association between each biomarker by quintile [Q] and odds of in-hospital death and a cardiovascular and thrombotic composite outcome.

RESULTS

Of 32,636 registry patients, 26,424 (81%) had admission values for ≥1 of the key biomarkers, of which 4,527 (17%) had admission values for all 5 biomarkers. Each biomarker revealed a significant gradient for in-hospital mortality from Q1 to Q5: D-dimer 14% to 35%, CRP 11%-32%, ferritin 11% to 30%, cTn 13% to 43%, and NPs 7% to 35% (P_trend for each <.001). After adjustment for other biomarkers and clinical variables, Q5 for NPs (OR:4.67, 95% CI: 3.05-7.14) retained the greatest relative odds for death; cTn (OR:2.68, 95% CI: 2.00-3.59) and NPs (OR:7.14, 95% CI: 4.92-10.37) were associated with the greatest odds of the CV composite. Q5 for D-dimer was associated with the highest risk of thrombotic events (OR: 9.02, 95% CI: 5.36-15.18).

CONCLUSIONS

Among patients hospitalized with COVID-19, cTn and NPs identified patients at high risk for an in-hospital adverse cardiovascular outcome, while elevations in D-dimer identified patients at risk for thrombotic complications.

High-Dose Prophylactic Anticoagulation for COVID-19 Pneumonia: A Review of Benefits and Risks

The COVID-19 pandemic has had a devastating impact on a global scale, causing significant morbidity and mortality. The virus affects multiple organ systems, including the respiratory, cardiovascular, and coagulation systems, leading to severe pneumonia in some patients. Moreover, COVID-19 patients with severe pneumonia have a high incidence of thrombotic events, which can result in significant morbidity and mortality. Given the potential benefits of anticoagulation therapy in COVID-19 patients with thrombotic complications, recent studies have proposed high-dose prophylactic anticoagulation (HD-PA) therapy as a potential treatment option. In fact, some studies have suggested that HD-PA therapy may be more effective in reducing thrombotic events and mortality rates than other treatment options. This review aims to provide a comprehensive overview of the benefits and risks of HD-PA therapy for COVID-19 pneumonia patients. By synthesizing and analyzing the latest available research, we highlight patient selection criteria and discuss the optimal dosage, duration, and timing of therapy. Additionally, we review the potential risks associated with HD-PA therapy and provide recommendations for clinical practice. Ultimately, this review provides valuable insights into the use of HD-PA therapy in COVID-19 pneumonia patients and paves the way for further research in this critical area. By exploring the benefits and risks of this treatment option, we hope to provide healthcare professionals with the information they need to make informed decisions about the best course of treatment for their patients.

Safety and Efficacy of Different Anticoagulant Doses for Patients with COVID-19 in the ICU: A Systematic Review and Meta-Analysis

Critically ill COVID-19 patients have a high incidence of thromboembolic events, which significantly influence the risk of mortality. Anticoagulant therapy is generally recommended to these patients but the optimal dosing regimens require further investigations. The objective of this systematic review and meta-analysis was to assess the efficacy and safety of prophylactic, intermediate and therapeutic dose anticoagulation in COVID-19 patients admitted to the ICU. A systematic search for original prospective observational studies and clinical trials was performed in online databases from 2020 to 2022. A total of 13 studies (3239 patients) were included. The type of anticoagulant dosing showed no significant influence on short-term mortality (p = 0.84), deep vein thrombosis (p = 0.66), arterial thrombosis (p = 0.44), major bleeding (p = 0.35) and minor bleeding incidence (p = 0.46). An anticoagulation regimen significantly influenced pulmonary embolism occurrence (16% for prophylactic dose vs. 4% for therapeutic dose, p = 0.02), but the number of studies in the analysis was relatively low. In conclusion, the results of this meta-analysis suggest that critically ill COVID-19 patients admitted in the ICU have no benefit from therapeutic doses of anticoagulants and that all three thromboprophylaxis regimes have a comparable effect on short term mortality and venous thromboembolism incidence but for pulmonary embolism, for which the results were inconclusive.

Retroperitoneal and abdominal bleeding in anticoagulated COVID-19 hospitalized patients: Case series and brief literature review

BACKGROUND

Hospitalized and severely ill coronavirus disease 2019 (COVID-19) patients necessitate prophylactic or therapeutic anticoagulation to minimize the risk of thrombosis at different sites. Life-threatening bleeding complications include spontaneous iliopsoas hematoma, peritoneal bleeding, and extra-abdominal manifestations such as intracranial hemorrhage.

CASE SUMMARY

Bleeding in the abdominal wall results in less severe complications than seen with iliopsoas hematoma or peritoneal bleeding. In our case series of 9 patients, we present retroperitoneal and abdominal bleeding complications following anticoagulation in hospitalized COVID-19 patients with severe acute respiratory syndrome coronavirus 2 pneumonia. Contrast-enhanced computed tomography (CE-CT) is the best imaging modality for assessing hematoma secondary to anticoagulation and determines the therapeutic approach, whether interventional, surgical, or conservative management.

CONCLUSION

We present the role of CE-CT for rapid and precise localization of the bleeding site and prognostic counseling. Finally, we provide a brief review of the literature.

Assessment of the Risk of Venous Thromboembolism in Nonhospitalized Patients With COVID-19

IMPORTANCE

Patients hospitalized with COVID-19 have higher rates of venous thromboembolism (VTE), but the risk and predictors of VTE among individuals with less severe COVID-19 managed in outpatient settings are less well understood.

OBJECTIVES

To assess the risk of VTE among outpatients with COVID-19 and identify independent predictors of VTE.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study was conducted at 2 integrated health care delivery systems in Northern and Southern California. Data for this study were obtained from the Kaiser Permanente Virtual Data Warehouse and electronic health records. Participants included nonhospitalized adults aged 18 years or older with COVID-19 diagnosed between January 1, 2020, and January 31, 2021, with follow-up through February 28, 2021.

EXPOSURES

Patient demographic and clinical characteristics identified from integrated electronic health records.

MAIN OUTCOMES AND MEASURES

The primary outcome was the rate per 100 person-years of diagnosed VTE, which was identified using an algorithm based on encounter diagnosis codes and natural language processing. Multivariable regression using a Fine-Gray subdistribution hazard model was used to identify variables independently associated with VTE risk. Multiple imputation was used to address missing data.

RESULTS

A total of 398 530 outpatients with COVID-19 were identified. The mean (SD) age was 43.8 (15.8) years, 53.7% were women, and 54.3% were of self-reported Hispanic ethnicity. There were 292 (0.1%) VTE events identified over the follow-up period, for an overall rate of 0.26 (95% CI, 0.24-0.30) per 100 person-years. The sharpest increase in VTE risk was observed during the first 30 days after COVID-19 diagnosis (unadjusted rate, 0.58; 95% CI, 0.51-0.67 per 100 person-years vs 0.09; 95% CI, 0.08-0.11 per 100 person-years after 30 days). In multivariable models, the following variables were associated with a higher risk for VTE in the setting of nonhospitalized COVID-19: age 55 to 64 years (HR 1.85 [95% CI, 1.26-2.72]), 65 to 74 years (3.43 [95% CI, 2.18-5.39]), 75 to 84 years (5.46 [95% CI, 3.20-9.34]), greater than or equal to 85 years (6.51 [95% CI, 3.05-13.86]), male gender (1.49 [95% CI, 1.15-1.96]), prior VTE (7.49 [95% CI, 4.29-13.07]), thrombophilia (2.52 [95% CI, 1.04-6.14]), inflammatory bowel disease (2.43 [95% CI, 1.02-5.80]), body mass index 30.0-39.9 (1.57 [95% CI, 1.06-2.34]), and body mass index greater than or equal to 40.0 (3.07 [1.95-4.83]).

CONCLUSIONS AND RELEVANCE

In this cohort study of outpatients with COVID-19, the absolute risk of VTE was low. Several patient-level factors were associated with higher VTE risk; these findings may help identify subsets of patients with COVID-19 who may benefit from more intensive surveillance or VTE preventive strategies.

Effectiveness of thromboprophylaxis with low molecular weight heparin in critically ill patients with COVID-19. An observational prospective, multicenter study

INTRODUCTION

COVID-19 induces coagulopathy associated with an increase of thromboembolic events. Due to the lack of agreement on recommendations for thromboprophylactic management, the aim of this study was to study the dosages of LMWH used in critically ill COVID-19 patients assessing the effect on their outcome.

METHODS

We evaluated data of the Reg-COVID19. According to LMWH dose two groups were analyzed: prophylaxis and treatment. Primary outcome was the relationship of LMWH dosage with mortality. Secondary outcomes included the incidence of thrombotic and bleeding events, length of ICU stay, invasive mechanical ventilation, and thrombotic and inflammatory parameters.

RESULTS

Data of 720 patients were analyzed, 258 in the prophylaxis group and 462 in the treatment group. C Reactive Protein, invasive mechanical ventilation, tocilizumab and corticosteroid treatments were related with the choice of LMWH dose. Hemorrhagic events (66/720, 9.2%) and thrombotic complications (69/720, 9.6%) were similar in both groups (p = .819 and p = .265), as was the time course of the thrombotic events, earlier than hemorrhagic ones (9 [3-18] and 12 [6-19] days respectively). Mortality was lower in prophylaxis group (25.2% versus 35.1%), but once an inverse probability weighting model was applied, we found no effect of LMWH dose.

CONCLUSION

We found no benefit or harm with the administration of therapeutic or prophylactic LMWH dose in COVID19 critically ill patients. With a similar rate of hemorrhagic or thrombotic events, the LMWH dose had no influence on mortality. More studies are needed to determine the optimal thromboprophylaxis protocol for critically ill patients.

Decreased protein C activity, lower ADAMTS13 antigen and free protein S levels accompanied by unchanged thrombin generation potential in hospitalized COVID-19 patients

INTRODUCTION

COVID-19 is associated with an increased thromboembolic risk. However, the mechanisms triggering clot formation in those patients remain unknown.

PATIENTS AND METHODS

In 118 adult Caucasian severe but non-critically ill COVID-19 patients (median age 58 years; 73 % men) and 46 controls, we analyzed in vitro plasma thrombin generation profile (calibrated automated thrombogram [CAT assay]) and investigated thrombophilia-related factors, such as protein C and antithrombin activity, free protein S level, presence of antiphospholipid antibodies and factor V Leiden R506Q and prothrombin G20210A mutations. We also measured circulating von Willebrand factor (vWF) antigen and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) antigen and activity. In patients, blood samples were collected on admission to the hospital before starting any therapy, including heparin. Finally, we examined the relationship between observed alterations and disease follow-up, such as thromboembolic complications.

RESULTS

COVID-19 patients showed 17 % lower protein C activity, 22 % decreased free protein S levels, and a higher prevalence of positive results for IgM anticardiolipin antibodies. They also had 151 % increased vWF, and 27 % decreased ADAMTS13 antigens compared with controls (p < 0.001, all). On the contrary, thrombin generation potential was similar to controls. In the follow-up, pulmonary embolism (PE) occurred in thirteen (11 %) patients. They were characterized by a 55 % elevated D-dimer (p = 0.04) and 2.7-fold higher troponin I (p = 0.002) during hospitalization and 29 % shorter time to thrombin peak in CAT assay (p = 0.009) compared to patients without PE.

CONCLUSIONS

In COVID-19, we documented prothrombotic abnormalities of peripheral blood. PE was characterized by more dynamic thrombin generation growth in CAT assay performed on admittance to the hospital.

Therapeutic considerations for prevention and treatment of thrombotic events in COVID-19

Thrombosis is a known complication of SARS-CoV-2 infection, particularly within a severely symptomatic subset of patients with COVID-19 disease, in whom an aggressive host immune response leads to cytokine storm syndrome (CSS). The incidence of thrombotic events coinciding with CSS may contribute to the severe morbidity and mortality observed in association with COVID-19. This review provides an overview of pharmacologic approaches based upon an emerging understanding of the mechanisms responsible for thrombosis across a spectrum of COVID-19 disease involving an interplay between immunologic and pro-thrombotic events, including endothelial injury, platelet activation, altered coagulation pathways, and impaired fibrinolysis.

[Effectiveness of thromboprophylaxis with low molecular weight heparin in critically ill patients with COVID-19. An observational prospective, multicenter study]

Introduction

COVID-19 induces coagulopathy associated with an increase of thromboembolic events. Due to the lack of agreement on recommendations for thromboprophylactic management, the aim of this study was to study the dosages of LMWH used in critically ill COVID-19 patients assessing the effect on their outcome.

Metohds

We evaluated data of the Reg-COVID19. According to LMWH dose two groups were analyzed: prophylaxis and treatment. Primary outcome was the relationship of LMWH dosage with mortality. Secondary outcomes included the incidence of thrombotic and bleeding events, length of ICU stay, invasive mechanical ventilation, and thrombotic and inflammatory parameters.

Results

Data of 720 patients were analyzed, 258 in the prophylaxis group and 462 in the treatment group. C Reactive Protein, invasive mechanical ventilation, tocilizumab and corticosteroid treatments were related with the choice of LMWH dose. Hemorrhagic events (66/720, 9.2%) and thrombotic complications (69/720, 9.6%) were similar in both groups (P=.819 and P=.265), as was the time course of the thrombotic events, earlier than hemorrhagic ones (9 [3-18] and 12 [6-19] days respectively). Mortality was lower in prophylaxis group (25.2% versus 35.1%), but once an inverse probability weighting model was applied, we found no effect of LMWH dose.

Conclusion

We found no benefit or harm with the administration of therapeutic or prophylactic LMWH dose in COVID19 critically ill patients. With a similar rate of hemorrhagic or thrombotic events, the LMWH dose had no influence on mortality. More studies are needed to determine the optimal thromboprophylaxis protocol for critically ill patients.

The Effect of Heparin Full-Dose Anticoagulation on Survival of Hospitalized, Non-critically Ill COVID-19 Patients: A Meta-analysis of High Quality Studies

BACKGROUND

International COVID-19 guidelines recommend thromboprophylaxis for non-critically ill inpatients to prevent thrombotic complications. It is still debated whether full-dose thromboprophylaxis reduces all-cause mortality. The main aim of this updated systematic review and meta-analysis is to evaluate the effect of full-dose heparin-based thromboprophylaxis on survival in hospitalized non-critically ill COVID-19 patients.

METHODS

A systematic review was performed across Pubmed/Medline, EMBASE, Cochrane Central Register of clinical trials, Clinicaltrials.gov, and medRxiv.org from inception to November 2022. We conducted a meta-analysis of randomized clinical trials (RCTs) comparing full-dose heparin-based anticoagulation to prophylactic or intermediate dose anticoagulation or standard treatment in hospitalized non-critically ill COVID-19 patients. The risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials and Grading of Recommendations Assessment, Development and Evaluation was applied. The primary outcome was all-cause mortality at the longest follow-up available.

RESULTS

We identified 6 multicenter RCTs involving 3297 patients from 13 countries across 4 continents. The rate of all-cause mortality was 6.2% (103/1662) in the full-dose group vs 7.7% (126/1635) in the prophylactic or intermediate dose group (Risk Ratio [RR] = 0.76; 95% confidence interval [CI] = 0.59-0.98; P = 0.037). The probabilities of any mortality difference and of NNT ≤ 100 were estimated at 98.2% and 84.5%, respectively. The risk of bias was low for all included RCTs and the strength of the evidence was "moderate."

CONCLUSION

Our meta-analysis of high-quality multicenter RCTs suggests that full-dose anticoagulation with heparin or low molecular weight heparin reduces all-cause mortality in hospitalized non-critically ill COVID-19 patients.

STUDY REGISTRATION

PROSPERO, review no. CRD42022348993.