Venous Thromboembolism in COVID-19 Compared to Non-COVID-19 Cohorts: A Systematic Review with Meta-Analysis

Cardiovascular disease risk after a SARS-CoV-2 infection: A systematic review and meta-analysis

OBJECTIVES

To our knowledge, there is no systematic review examining CVD risks after a SARS-CoV-2 infection over time, while also taking into account disease severity. All evidence on the risk for pulmonary embolism (PE), myocardial infarction (MI), ischaemic stroke (IS), haemorrhagic stroke (HS), and arterial thrombosis following infection was evaluated.

METHODS

The protocol was registered with PROSPERO. We searched Pubmed, Embase, MedRxiv and screened the titles/abstracts and full texts. We extracted the included studies, assessed their quality, and estimated pooled risks by time after infection and according to disease severity.

RESULTS

Risks were highest in the acute phase [PE: 27.1 (17.8-41.10); MI: 4.4 (1.6-12.4); stroke: 3.3 (2.1-5.2); IS: 5.6 (2.1-14.8); HS: 4.0 (0.1-326.2)] compared to the post-acute phase [PE: 2.9 (2.6-3.3); MI: 1.4 (1.1-1.9); stroke: 1.4 (1.0-2.0); IS: 1.6 (0.9-2.7)]. Highest risks were observed after infection confirmation, dropping during the first month post-infection (e.g. PE: RR(7 days) = 31; RR(1 month) = 8.1). A doubled risk was still observed until 4.5 months for PE, one month for MI and two months for IS. Risks decreased with decreasing disease severity.

CONCLUSIONS

Because of increased risk of CVD outcomes, management of persons who survived a severe SARS-CoV-2 infection is required, especially during the first nine months post-infection.

A Review of Thyroid Dysfunction Due to COVID-19

Coronavirus disease 2019 (COVID-19) affects thyroid function. These changes are due to the direct impact of the virus on thyroid cells via angiotensin-converting-enzyme 2 (ACE2) receptors, inflammatory reaction, apoptosis in thyroid follicular cells, suppression of hypothalamus-pituitarythyroid axis, an increase in activity of adrenocortical axis, and excess cortisol release due to cytokine storm of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Euthyroid sick syndrome (ESS), thyroiditis, clinical and subclinical hypothyroidism, central hypothyroidism, exacerbation of underlying autoimmune thyroid disease, and clinical and subclinical hyperthyroidism can be associated with coronavirus. Adjuvants in coronavirus vaccines induce autoimmune/inflammatory syndrome known as vaccine adjuvants (ASIA) syndrome. Thyroiditis and Graves' disease have been reported to be associated with ASIA syndrome after some coronavirus vaccinations. Some coronavirus medications, such as hydroxychloroquine, monoclonal antibodies, lopinavir/ritonavir, remdesivir, naproxen, anticoagulants, and glucocorticoids can also affect thyroid tests, and correct diagnosis of thyroid disorders will be more difficult. Changes in thyroid tests may be one of the most important manifestations of COVID-19. These changes can be confusing for clinicians and can lead to inappropriate diagnoses and decisions. Prospective studies should be conducted in the future to increase epidemiological and clinical data and optimize the management of thyroid dysfunctions in patients with COVID-19.

What Is the Impact of Baseline Inflammatory and Hemostatic Indicators with the Risk of Mortality in Severe Inpatients with COVID-19: A Retrospective Study

The purpose of the study was to investigate baseline inflammatory, hemostatic indicators and new-onset deep vein thrombosis (DVT) with the risk of mortality in COVID-19 inpatients. In this single-center study, a total of 401 COVID-19 patients hospitalized in Sir Run Run Shaw Hospital, Zhejiang University School of Medicine were enrolled from December 1, 2022 to January 31, 2023. The basic information, first laboratory examination results, imaging examination, and outcome-related indicators were compared between patients in the moderate and severe subgroups. We found that baseline D-dimer and baseline absolute neutrophil count (ANC) levels were associated with new-onset DVT and death in severe hospitalized patients with COVID-19. The odds ratio (OR) of baseline D-dimer and baseline ANC with mortality was 1.18 (95% confidence interval [CI], 1.08-1.28; P < .001) and 1.13 (95% CI, 1.06-1.21; P < .001). Baseline ANC was associated with the risk of death in severe hospitalized COVID-19 patients, irrespective of the DVT status. In addition, a significantly higher serum neutrophil activity was observed in severe COVID-19 inpatients with DVT or those deceased during hospital stay. New-onset DVT partially mediated the association between baseline D-dimer (indirect effect: 0.011, estimated mediating proportion: 67.0%), baseline ANC (indirect effect: 0.006, estimated mediating proportion: 48.7%), and mortality in severe hospitalized patients with COVID-19. In summary, baseline D-dimer and baseline absolute neutrophil count (ANC) levels were associated with the mortality in severe hospitalized patients with COVID-19, especially DVT inpatients. New-onset DVT partially mediated the association between baseline D-dimer, baseline ANC, and mortality in severe hospitalized patients with COVID-19.

Medical Emergencies in Pulmonary Hypertension

The management of acute medical emergencies in patients with pulmonary hypertension (PH) can be challenging. Patients with preexisting PH can rapidly deteriorate due to right ventricular decompensation when faced with acute physiological challenges that would usually be considered low-risk scenarios. This review considers the assessment and management of acute medical emergencies in patients with PH, encompassing both pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH), acknowledging these comprise the more severe groups of PH. Management protocols are described in a systems-based approach. Respiratory emergencies include pulmonary embolism, airways disease, and pneumonia; cardiac emergencies including arrhythmia and chest pain with acute myocardial infarction are discussed, alongside PH-specific emergencies such as pulmonary artery dissection and extrinsic coronary artery compression by a dilated proximal pulmonary artery. Other emergencies including sepsis, severe gastroenteritis with dehydration, syncope, and liver failure are also considered. We propose management recommendations for medical emergencies based on available evidence, international guidelines, and expert consensus. We aim to provide advice to the specialist alongside the generalist, and emergency doctors, nurses, and acute physicians in nonspecialist centers. A multidisciplinary team approach is essential in the management of patients with PH, and communication with local and specialist PH centers is paramount. Close hemodynamic monitoring during medical emergencies in patients with preexisting PH is vital, with early referral to critical care recommended given the frequent deterioration and high mortality in this setting.

Pathophysiological Aspects of COVID-19-Associated Vasculopathic Diseases

Since the beginning of coronavirus disease 2019 (COVID-19) pandemic, numerous data reported potential effects on the cardiovascular system due to infection by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), which may lead to COVID-19-associated vasculopathies during the acute phase and measurable vascular changes in the convalescent phase. Infection by SARS-CoV-2 seems to have specific direct and indirect effects on the endothelium, immune and coagulation systems thus promoting endothelial dysfunction, immunothrombosis, and formation of neutrophil extracellular traps although the exact mechanisms still need to be elucidated. This review represents a recent update of pathophysiological pathways of the respective three major mechanisms contributing to COVID-19 vasculopathies and vascular changes and includes clinical implications and significance of outcome data.

Venous thromboembolism and major bleeding in severe and critical COVID-19 hospitalized patients

Venous thromboembolism (VTE) and major bleeding (MB) are life-threatening complications described in COVID-19 hospitalized patients, and they can be considered two sides of the same coin. This retrospective study aims to evaluate the risk factors for VTE and MB in COVID-19 patients admitted to two Italian hospitals. The medical records of all COVID-19 patients (males 139; 62.3%, mean age 67.2±13.6 years, body weight 88.2±20.6 kg) hospitalized from March 11th to July 31st, 2020, at the Federico II University Hospital and the Sea Hospital, Naples, Italy, were analyzed. The COVID-19 patients were classified into four groups: COVID-19 patients developing VTE and/or MB, COVID-19 patients developing only VTE, COVID-19 patients developing only MB, and COVID-19 patients not developing either VTE or MB. During the hospitalization, 53 COVID-19 patients (24.7%; males 40; 75.5%, mean age 67.2±13.6 years, weight 88.2±20.6 kg) developed VTE, 33 COVID-19 patients (15.3%; males 17; 51.5, mean age 67.3±14.9 years, weight 74.1±14.3 kg) developed MB, and 129 COVID-19 patients did not develop either TVP or MB. No parameters to identify severe COVID-19 complicated by VTE and/or MB were found. However, some clinical and biochemical parameters can be evaluated to predict the risk of MB in order to modify the treatment and take prompt action to reduce mortality.

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.

Impact of COVID-19 on Patients Hospitalized With Deep Vein Thrombosis and/or Pulmonary Embolism: A Nationwide Analysis

The Coronavirus disease 2019 (COVID-19) infection predisposes patients to develop deep vein thrombosis (DVT) and pulmonary embolism (PE). In this study, we compared the in-hospital outcomes of patients with DVT and/or PE with concurrent COVID-19 infection vs those with concurrent flu infection. The National Inpatient Sample from 2019 to 2020 was analyzed to identify all adult admissions diagnosed with DVT and PE. These patients were then stratified based on whether they had concomitant COVID-19 or flu. We identified 62,895 hospitalizations with the diagnosis of DVT and/or PE with concomitant COVID-19, and 8155 hospitalizations with DVT and/or PE with concomitant flu infection. After 1:1 propensity score match, the incidence of cardiac arrest and inpatient mortality were higher in the COVID-19 group. The incidence of cardiogenic shock was higher in the flu group. Increased age, Hispanic race, diabetes, chronic kidney disease, arrhythmia, liver disease, coagulopathy, and rheumatologic diseases were the independent predictors of mortality in patients with DVT and/or PE with concomitant COVID-19.

Rivaroxaban in Outpatients with Mild or Moderate COVID-19: Rationale and Design of the Study CARE (CARE - Coalition COVID-19 Brazil VIII)

BACKGROUND

Previous studies have demonstrated a high risk of arterial and venous thromboembolic events as a consequence of direct viral damage to endothelial cells by SARS-CoV-2 and a procoagulant milieu due to increased biomarkers, such as D-dimer, fibrinogen, and factor VIII. Although randomized controlled trials of antithrombotic therapies have been conducted in hospitalized patients, few have evaluated the role of thromboprophylaxis in an outpatient setting.

OBJECTIVE

To assess whether antithrombotic prophylaxis with rivaroxaban reduces the risk of venous or arterial thrombotic events, invasive ventilatory support, and death in COVID-19 outpatients.

METHODS

The COVID Antithrombotic Rivaroxaban Evaluation (CARE) study, a multicenter, randomized, open-label, controlled trial of rivaroxaban 10 mg once daily for 14 days or local standard treatment alone to prevent adverse outcomes, is registered in clinicaltrials.gov (NCT04757857). The inclusion criteria are adults with confirmed or suspected SARS-CoV-2 infection and mild or moderate symptoms without indication for hospitalization, within 7 days of symptom onset, and 1 risk factor for COVID-19 complication (> 65 years, hypertension, diabetes mellitus, asthma, chronic obstructive pulmonary disease or other chronic lung diseases, smoking, immunosuppression, or obesity). The primary composite endpoint, which includes venous thromboembolism, invasive mechanical ventilation, major acute cardiovascular events, and mortality within 30 days of randomization, will be assessed according to the intention-to-treat principle. All patients will provide informed consent. A significance level of 5% will be used for all statistical tests.

RESULTS

Major thrombotic and bleeding outcomes, hospitalizations, and deaths will be centrally adjudicated by an independent clinical events committee blinded to the assigned treatment groups.

CONCLUSION

The CARE study will provide relevant and contemporary information about the potential role of thromboprophylaxis in outpatients with COVID-19.

COVID-19 Thrombotic Complications and Therapeutic Strategies

Shortly after the emergence of coronavirus disease 2019 (COVID-19) in late 2019, clinicians rapidly recognized an apparent association between the disease and both arterial and venous thrombotic complications, which was confirmed in epidemiologic studies. Based on these data, hospitals empirically developed and implemented protocols with different strategies for anticoagulation of hospitalized COVID-19 patients. Subsequent randomized controlled trials (RCTs) clarified the role of anticoagulation in patients hospitalized with COVID-19 and recently discharged from the hospital. In this review, we discuss the epidemiology and pathophysiology of thrombosis in patients with COVID-19, observational comparative effectiveness analyses that provided hints of a benefit from anticoagulation, and finally the RCTs that established which patients with COVID-19 benefit from treatment-dose anticoagulation. These RCTs have demonstrated that hospitalized, noncritically ill patients with COVID-19 benefit from treatment-dose anticoagulation, but patients who are hospitalized and critically ill, discharged from the hospital, or not hospitalized do not benefit.

Predictive value of inflammatory and coagulation biomarkers for venous thromboembolism in Covid-19 patients

BACKGROUND

The predictive value of coagulation markers for venous thromboembolism (VTE) in Covid-19 patients has been investigated with conflicting results.

OBJECTIVE

Our aim was to investigate the correlation between biomarkers and VTE and the predictive value of D-dimer for VTE in hospitalized Covid-19 patients.

METHODS

Complete blood count, inflammatory and coagulation biomarkers at admission were collected. VTE was defined as diagnosed pulmonary embolism or deep vein thrombosis. Events were defined as in-hospital death or ICU admission. Predictors of VTE were identified with Pearson prediction models. A ROC curve was constructed to assess the predictive value of D-dimer.

RESULTS

1651 participants were included, 111 VTE were identified. Events incidence was higher in the VTE group (49.5% vs 28.2%, p <  0.001). Neutrophil-lymphocyte ratio (NLR, 0.001; 95% CI 0.000-0.002; p 0.019) and D-dimer (0.00005; 95% CI 0.00002-0.00008; p <  0.001), Geneva score (0.026; 95% CI 0.012-0.040; p <  0.001) and Wells score (0.047; 95% CI 0.033-0.061; p <  0.001) were associated with VTE. D-dimer had a goor predictive value for VTE (ROC area 0.85, 95% CI 0.816-0.893), with an optimal cut-off value of 2677μg/L (Youden index of 0,602).

CONCLUSIONS

Among coagulation biomarkers D-dimer had the best predictive value for VTE, but higher cut-off values should be used in Covid-19.

Perioperative Prevention of Venous Thromboembolism in Abdominal Surgery Patients Based on the Caprini or the Padua Risk Score-A Single Centre Prospective Observational Study

Surgical patients should receive perioperative thromboprophylaxis based on risk assessment, and the Caprini score is validated for this purpose. Whether the Padua score, originally devised for medical patients, can be useful in surgical patients remains to be fully clarified. This study aimed to evaluate perioperative thromboprophylaxis based on the Caprini or the Padua score in elective abdominal surgery. A total of 223 patients undergoing elective abdominal surgery for malignant or benign disease were prospectively evaluated. The patients were divided into two groups in which thromboprophylaxis was prescribed according to either the Caprini score (n = 122) or the Padua score (n = 101). Patients with high-risk scores in both groups received nadroparin. The alternate risk score in each group was calculated for evaluation purposes only. During a 3-month follow-up, we assessed patients for symptomatic venous thromboembolism (VTE), bleeding, or mortality. In the Caprini score group, 87 patients (71%) had a high risk for VTE (≥5 points), while 38 patients (38%) had a high risk for VTE (≥4 points) in the Padua score group; p < 0.00001. The overall correlation between the Caprini and Padua scores was moderate (r= 0.619), with 85 patients having high Caprini and discordant Padua scores. Ten patients died during follow-up (4.5%), and five developed non-fatal symptomatic VTE (2.2%). Among the five major bleeding incidents recorded (1.8%), two cases were possibly associated with pharmacological thromboprophylaxis. The incidence of adverse outcomes did not differ between the two groups. The odds ratio for adverse outcomes was significantly higher with a high Caprini or Padua risk score, malignant disease, age ≥65 years, and active smoking. We found no significant differences in adverse outcomes between abdominal surgical patients who received perioperative thromboprophylaxis based on either the Caprini or the Padua risk score. However, a discordant Padua score was noted in almost 40% of patients who had a high Caprini score, suggesting that the latter may be more sensitive than the Padua score in surgical patients.

Association of COVID-19 vs Influenza With Risk of Arterial and Venous Thrombotic Events Among Hospitalized Patients

IMPORTANCE

The incidence of arterial thromboembolism and venous thromboembolism in persons with COVID-19 remains unclear.

OBJECTIVE

To measure the 90-day risk of arterial thromboembolism and venous thromboembolism in patients hospitalized with COVID-19 before or during COVID-19 vaccine availability vs patients hospitalized with influenza.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of 41 443 patients hospitalized with COVID-19 before vaccine availability (April-November 2020), 44 194 patients hospitalized with COVID-19 during vaccine availability (December 2020-May 2021), and 8269 patients hospitalized with influenza (October 2018-April 2019) in the US Food and Drug Administration Sentinel System (data from 2 national health insurers and 4 regional integrated health systems).

EXPOSURES

COVID-19 or influenza (identified by hospital diagnosis or nucleic acid test).

MAIN OUTCOMES AND MEASURES

Hospital diagnosis of arterial thromboembolism (acute myocardial infarction or ischemic stroke) and venous thromboembolism (deep vein thrombosis or pulmonary embolism) within 90 days. Outcomes were ascertained through July 2019 for patients with influenza and through August 2021 for patients with COVID-19. Propensity scores with fine stratification were developed to account for differences between the influenza and COVID-19 cohorts. Weighted Cox regression was used to estimate the adjusted hazard ratios (HRs) for outcomes during each COVID-19 vaccine availability period vs the influenza period.

RESULTS

A total of 85 637 patients with COVID-19 (mean age, 72 [SD, 13.0] years; 50.5% were male) and 8269 with influenza (mean age, 72 [SD, 13.3] years; 45.0% were male) were included. The 90-day absolute risk of arterial thromboembolism was 14.4% (95% CI, 13.6%-15.2%) in patients with influenza vs 15.8% (95% CI, 15.5%-16.2%) in patients with COVID-19 before vaccine availability (risk difference, 1.4% [95% CI, 1.0%-2.3%]) and 16.3% (95% CI, 16.0%-16.6%) in patients with COVID-19 during vaccine availability (risk difference, 1.9% [95% CI, 1.1%-2.7%]). Compared with patients with influenza, the risk of arterial thromboembolism was not significantly higher among patients with COVID-19 before vaccine availability (adjusted HR, 1.04 [95% CI, 0.97-1.11]) or during vaccine availability (adjusted HR, 1.07 [95% CI, 1.00-1.14]). The 90-day absolute risk of venous thromboembolism was 5.3% (95% CI, 4.9%-5.8%) in patients with influenza vs 9.5% (95% CI, 9.2%-9.7%) in patients with COVID-19 before vaccine availability (risk difference, 4.1% [95% CI, 3.6%-4.7%]) and 10.9% (95% CI, 10.6%-11.1%) in patients with COVID-19 during vaccine availability (risk difference, 5.5% [95% CI, 5.0%-6.1%]). Compared with patients with influenza, the risk of venous thromboembolism was significantly higher among patients with COVID-19 before vaccine availability (adjusted HR, 1.60 [95% CI, 1.43-1.79]) and during vaccine availability (adjusted HR, 1.89 [95% CI, 1.68-2.12]).

CONCLUSIONS AND RELEVANCE

Based on data from a US public health surveillance system, hospitalization with COVID-19 before and during vaccine availability, vs hospitalization with influenza in 2018-2019, was significantly associated with a higher risk of venous thromboembolism within 90 days, but there was no significant difference in the risk of arterial thromboembolism within 90 days.

Antithrombotic and antiplatelet effects of plant-derived compounds: a great utility potential for primary, secondary, and tertiary care in the framework of 3P medicine

Thromboembolism is the third leading vascular disease, with a high annual incidence of 1 to 2 cases per 1000 individuals within the general population. The broader term venous thromboembolism generally refers to deep vein thrombosis, pulmonary embolism, and/or a combination of both. Therefore, thromboembolism can affect both – the central and peripheral veins. Arterial thromboembolism causes systemic ischemia by disturbing blood flow and oxygen supply to organs, tissues, and cells causing, therefore, apoptosis and/or necrosis in the affected tissues. Currently applied antithrombotic drugs used, e.g. to protect affected individuals against ischemic stroke, demonstrate significant limitations. For example, platelet inhibitors possess only moderate efficacy. On the other hand, thrombolytics and anticoagulants significantly increase hemorrhage. Contextually, new approaches are extensively under consideration to develop next-generation antithrombotics with improved efficacy and more personalized and targeted application. To this end, phytochemicals show potent antithrombotic efficacy demonstrated in numerous in vitro, ex vivo, and in vivo models as well as in clinical evaluations conducted on healthy individuals and persons at high risk of thrombotic events, such as pregnant women (primary care), cancer, and COVID-19-affected patients (secondary and tertiary care). Here, we hypothesized that specific antithrombotic and antiplatelet effects of plant-derived compounds might be of great clinical utility in primary, secondary, and tertiary care. To increase the efficacy, precise patient stratification based on predictive diagnostics is essential for targeted protection and treatments tailored to the person in the framework of 3P medicine. Contextually, this paper aims at critical review toward the involvement of specific classes of phytochemicals in antiplatelet and anticoagulation adapted to clinical needs. The paper exemplifies selected plant-derived drugs, plant extracts, and whole plant foods/herbs demonstrating their specific antithrombotic, antiplatelet, and fibrinolytic activities relevant for primary, secondary, and tertiary care. One of the examples considered is antithrombotic and antiplatelet protection specifically relevant for COVID-19-affected patient groups.

Sports Imaging of COVID-19: A Multi-Organ System Review of Indications and Imaging Findings

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in December 2019 in Wuhan, China. Although coronavirus disease-19 (COVID-19) affects every population group, the sports community and athletes require special consideration of the effects on cardiovascular, musculoskeletal, neurologic, and respiratory systems. A comprehensive understanding of imaging indications, findings, and features of COVID-19 supports appropriate imaging utilization and effective patient management and treatment.

PURPOSE

To review the spectrum of sports imaging in COVID-19 infection, organ system manifestations, vaccine effects, and complications in recreational and competitive athletes.

STUDY DESIGN

Narrative review.

LEVEL OF EVIDENCE

Levels 4 and 5.

METHODS

Based on a PubMed database search, studies describing the imaging findings of COVID-19 infection, organ system manifestations, vaccine effects, and complications in recreational and competitive athletes were included.

RESULTS

On March 11, 2020, World Health Organization officially declared COVID-19 a global pandemic. As of May 9, 2022, more than 515 million confirmed cases of COVID-19 were reported globally. While the multisystem effects of COVID-19 are incompletely understood, the role of imaging in diagnosing, monitoring, and prognosticating active disease, long-term effects, and complications is evolving. In the respiratory system, imaging plays an important role in diagnosing, characterizing, and monitoring pulmonary COVID-19 infections, barotrauma, and COVID-19-associated chronic pulmonary opacities and fibrotic-like lung changes. Ultrasonography, computed tomography, and magnetic resonance imaging aid in the timely diagnosis of ischemic, embolic, and thrombotic peripheral and central cardiovascular events, including deep venous thrombosis, pulmonary embolism, myocarditis, and stroke. COVID-19-associated musculoskeletal and peripheral nervous system manifestations include rhabdomyolysis and myonecrosis, plexus and peripheral neuropathies, Guillain-Barré syndrome, and shoulder injury related to vaccine administration.

CONCLUSIONS

In athletes, COVID-19 infections and associated effects on cardiovascular, musculoskeletal, neurologic, and respiratory systems require special consideration. With the increasing understanding of the multisystem effects of COVID-19, the role of imaging in diagnosing, monitoring, and prognosticating active disease, long-term effects, and complications is evolving. A comprehensive understanding of imaging indications, COVID-19 imaging features, and organ system effects aids in appropriate imaging utilization and effective patient management and treatments.

The Incidence of Venous Thromboembolism in Critically Ill Patients with SARS-CoV-2 Infection Compared with Critically Ill Influenza and Community-Acquired Pneumonia Patients: A Retrospective Chart Review

The rate of venous thromboembolism in COVID-19 patients has been reported to be 30% (deep vein thrombosis 20% and pulmonary embolism 18%). This has been shown to be higher in COVID-19 patients admitted to the ICU. Prophylactic anticoagulation may be sufficient at ward level, but not in intensive care. A retrospective chart review was undertaken in a large university hospital. The review included 276 patients from COVID-19 Wave 1, COVID-19 Wave 2, influenza, and community-acquired pneumonia groups. The timeframe included patients admitted between 23 February 2014 and 12 May 2021. Clinical characteristics, outcomes, blood results, rates of venous thromboembolism, and anticoagulation status were recorded. The incidence of venous thromboembolism in COVID-19 Wave 1, COVID-19 Wave 2, influenza, and community-acquired pneumonia was 10.91%, 13.69%, 13.33%, and 6.81%, respectively (p = 0.481). The incidence of pulmonary embolism was 7.27%, 10.95%, 3.33%, and 5.68%, respectively (p = 0.350). The incidence of deep vein thrombosis was 5.45%, 5.48%, 10.00%, and 1.14%, respectively (p = 0.117). Although most patients were prophylactically anticoagulated, venous thromboembolism still occurred. Venous thromboembolism remains an important differential to consider in critically ill COVID-19 patients. The current literature does not advise therapeutic anticoagulation for thromboprophylaxis in the ICU.

Anticoagulant Treatment in Severe ARDS COVID-19 Patients

Patients with COVID-19 may complicate their evolution with thromboembolic events. Incidence of thromboembolic complications are high and also, patients with the critically-ill disease showed evidence of microthrombi and microangiopathy in the lung probably due to endothelial damage by directly and indirectly injured endothelial and epithelial cells. Pulmonary embolism, deep venous thrombosis and arterial embolism were reported in patients with COVID-19, and several analytical abnormal coagulation parameters have been described as well. D-dimer, longer coagulation times and lower platelet counts have been associated with poor outcomes. The use of anticoagulation or high doses of prophylactic heparin is controversial. Despite the use of anticoagulation or high prophylactic dose of heparin have been associated with better outcomes in observational studies, only in patients with non-critically ill disease benefits for anticoagulation was observed. In critically-ill patient, anticoagulation was not associated with better outcomes. Other measures such as antiplatelet therapy, fibrinolytic therapy or nebulized anticoagulants are being studied in ongoing clinical trials.

Venous Thromboembolism and COVID-19-an Epidemiological Perspective

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was declared as pandemic by World Health Organization (WHO) in March 2020. The outbreak has caused 5,232,562 deaths worldwide until December 3rd, 2021. Though primarily affecting the respiratory system, involvement of other organ systems have been reported in severe disease. Venous thromboembolism (VTE) has been recognized as an important complication. Previous studies have reported the prevalence of VTE in intensive care unit (ICU) patients between 7 and 85% and in non-ICU patients between 0 and 19%. COVID-19 patients that are at high risk for VTE are also at increased risk for bleeding. In such cases, anticoagulation may potentially be harmful. Thereby, it is important to understand the risk factors for VTE predisposition in the COVID-19 patients, timing of VTE, and the rate of occurrence of VTE in hospitalized patients post-discharge. Comparison of the rate of occurrence of VTE in COVID-19 patients with the non-COVID-19 patients with similar disease severity is required to truly interpret the reportedly high rates of VTE in COVID-19 patients. Several pathophysiological mechanisms have been reported for the development of VTE in COVID-19. Autopsy-based studies have contributed to the existing knowledge. d-dimer, presently, seems to be the most suitable investigation for risk-identification of VTE supported by Doppler studies and overall clinical context. Further, prospective studies and clinical trials are essentially required to fill the gaps in evidence for occurrence, risk prediction and management of VTE in COVID-19 patients.

SIT1 transporter as a potential novel target in treatment of COVID-19

Studies published earlier this year demonstrated the association of the solute carrier SLC6A20 gene with the risk and severity of COVID-19. The SLC6A20 protein product (Sodium-dependent Imino Transporter 1 (SIT1)) is involved in the transport of amino acids, including glycine. Here we summarized the results of recent studies demonstrating the interaction of SIT1 with the ACE2 receptor for SARS-CoV-2 as well as an observed association of SLC6A20 with the risk and traits of Type 2 diabetes (T2D). Recently, it was also proposed that SLC6A20 represents the novel regulator of glycine levels and that glycine has beneficial effects against the proinflammatory cytokine secretion induced by SARS-CoV-2 infection. Ivermectin, as a partial agonist of glycine-gated chloride channels, was also recently suggested to interfere with the COVID-19 cytokine storm by inducing the activation of glycine receptors. Furthermore, plasma glycine levels are found to be decreased in diabetic patients. Thus, further clinical trials are warranted to confirm the potential favorable effects of targeting the SIT1 transporter and glycine levels in the treatment of COVID-19, particularly for the severe case of disease associated with hyperglycemia, inflammation, and T2D. These findings suggest that SIT1 may potentially represent one of the missing pieces in the complex puzzle observed between these two pandemic diseases and the potential novel target for their efficient treatment.