Abnormal Hemostatic Parameters and Risk of Thromboembolism Among Patients With COVID-19 Infection

Angiography-based coronary microvascular assessment with and without intracoronary pressure measurements: a systematic review

BACKGROUND

In recent years, several indices have been proposed for quantifying coronary microvascular resistance. We intended to conduct a comprehensive review that systematically evaluates indices of microvascular resistance derived from angiography.

OBJECTIVE

The objective of this study was to identify and analyze angiography-derived indices of microvascular resistance that have been validated against an invasive reference method. We aimed to compare their limits of agreement with their reference methods and explore their advantages and inherent limitations.

METHODS AND RESULTS

We searched PubMed from inception until 2022 for studies on different techniques for quantifying microvascular resistance. Seven studies met the inclusion criteria. Five studies included techniques that applied calculations based solely on invasive angiography, and were validated against invasively measured thermodilution-derived index of microvascular resistance. The remaining two studies combined angiography with invasively measured intracoronary pressure data, and were validated against invasive Doppler measurements. We converted the ± 1.96 standard deviation limits of agreement with the reference method from the seven studies into percentages relative to the cut-off value of the reference method. The lower limits of agreement for angiography-based methods ranged from - 122 to - 60%, while the upper limits ranged from 74 to 135%. The range of the limits of agreement was considerably lower for the two combined angiography- and pressure-based methods, standing at - 52 to 60% and - 25 to 27%.

CONCLUSION

Our findings suggest that combined angiography- and pressure-based methods provide a more reliable assessment of microvascular resistance compared to methods relying solely on angiography. Central illustration. Comparative assessment of image-based methods quantifying microvascular resistance with and without intracoronary pressure measurements. Angiography-based methods rely on angiography alone to calculate the microvascular resistance by utilizing angiographic frame counting to extrapolate coronary flow (Q) and subsequently deriving distal coronary pressure using fluid dynamic equations. Combined angiography- and pressure-based methods utilize invasive intracoronary pressure gradients measured during rest and maximal vasodilation to determine coronary flow in their calculation of microvascular resistance. The combined methods showed more acceptable levels of agreement with their reference methods compared to angiography-based methods alone.

Effet protecteur des alpha-bloquants dans la Covid-19

Introduction

Patients et méthodes

Résultats

Conclusion

Association between Heparin Dose and 6-Week Mortality in Patients with COVID-19

Background

Severe forms of SARS-CoV-2 infections are associated with high rates of thromboembolic complications. Professional societies and expert consensus reports have recommended anticoagulants for COVID-19 hospitalized patients. Our study aimed to compare the effect of therapeutic, intermediate and prophylactic doses of heparin on 6-week survival in patients hospitalized for COVID-19.

Methods

The study sample is a French cohort of COVID-19 patients hospitalized between Feb 25th and Apr 30th 2020. Patients were assigned to one of 3 anticoagulation dose groups based on the maximum dose they received for at least three days (prophylactic, intermediate or therapeutic). The main outcome was survival up to 42 days after hospital admission. Multivariate Cox regression models were performed to adjust analyses for confounding factors.

Results

A total of 323 patients were included. The mean age of the study sample was 71.6 ± 15 years, and 56.3% were men. Treatment with the intermediate versus prophylactic dose of anticoagulation (HR = 0.50, 95%CI = [0.26; 0.99], p = 0.047) and with therapeutic versus prophylactic dose (HR = 0.58 95%CI = [0.34; 0.98], p = 0.044) was associated with a significant reduction in 6-week mortality, after adjustment for potential confounding factors. Comparison of therapeutic versus intermediate doses showed no significant difference in survival.

Conclusions

Our results reported a significant positive effect of intermediate and therapeutic doses of heparin on 6-week survival for hospitalized COVID-19 patients compared with a prophylactic dose.

SPECT myocardial perfusion imaging identifies myocardial ischemia in patients with a history of COVID-19 without coronary artery disease

We aimed to examine the effect of a history of COVID-19 on myocardial ischemia in single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients who presented with shortness of breath and/or chest pain after recovery. For this single-center retrospective study, patients who presented at cardiology outpatient clinics and had SPECT-MPI were screened. A total of 1888 patients were included in the study, 340 of whom had a history of COVID-19. 64 patients with > 50% stenosis on coronary angiography were excluded from the study. The primary outcome of the study was abnormal MPI. In the study population, the median age was 56 (49–64 IQR) years, and 1127 (65%) of the patients were female. Abnormal MPI was detected in 77 patients (23%) in the COVID-19 group and in 244 patients (16%) in the non–COVID-19 group. After adjustment was performed for clinical predictors using Bayesian logistic regression, an important association was found between the presence of a confirmed prior COVID-19 infection and abnormal MPI (posterior median odds ratio, 1.70 [95% CrI, 1.20–2.40], risk difference, 9.6% [95% CrI, 1.8%, 19.7%]). In SPECT-MPI, ischemia rates were observed to be higher in COVID-19 group and it was found that a confirmed prior COVID-19 might predict of abnormal MPI.

Coronary microvascular dysfunction pathophysiology in COVID-19

Recently, accumulating evidence has highlighted the role of endothelial dysfunction in COVID-19 progression. Coronary microvascular dysfunction (CMD) plays a pivotal role in cardiovascular disease (CVD) and CVD-related risk factors (eg, age, gender, hypertension, diabetes mellitus, and obesity). Equally, these are also risk factors for COVID-19. The purpose of this review was to explore CMD pathophysiology in COVID-19, based on recent evidence. COVID-19 mechanisms were reviewed in terms of imbalanced renin-angiotensin-aldosterone-systems (RAAS), systemic inflammation and immune responses, endothelial dysfunction, and coagulatory disorders. Based on these mechanisms, we addressed CMD pathophysiology within the context of COVID-19, from five perspectives. The first was the disarrangement of local RAAS and Kallikrein-kinin-systems attributable to SARS-Cov-2 entry, and the concomitant decrease in coronary microvascular endothelial angiotensin I converting enzyme 2 (ACE2) levels. The second was related to coronary microvascular obstruction, induced by COVID-19-associated systemic hyper-inflammation and pro-thrombotic state. The third was focused on how pneumonia/acute respiratory distress syndrome (ARDS)-related systemic hypoxia elicited oxidative stress in coronary microvessels and cardiac sympathetic nerve activation. Fourthly, we discussed how autonomic nerve dysfunction mediated by COVID-19-associated mental, physical, or physiological factors could elicit changes in coronary blood flow, resulting in CMD in COVID-19 patients. Finally, we analyzed reciprocity between the coronary microvascular endothelium and perivascular cellular structures due to viremia, SARS-CoV-2 dissemination, and systemic inflammation. These mechanisms may function either consecutively or intermittently, finally culminating in CMD-mediated cardiovascular symptoms in COVID-19 patients. However, the underlying molecular pathogenesis remains to be clarified.

Association of coagulation disturbances with severity of COVID-19: a longitudinal study

OBJECTIVES

Coagulation dysfunction is an evident factor in the clinical diagnosis and treatment of patients with coronavirus disease 2019 (COVID-19), appearing even in COVID-19 patients with normal inflammation indices. Therefore, this study aimed to analyze the characteristics of coagulation function indices in COVID-19 patients to investigate possible mechanisms through the comparison of non-severe and severe COVID-19 patients.

METHODS

We included 143 patients whose clinical characteristics, coagulation function, and other indices such as inflammatory factors were collected and compared based on disease severity.

RESULTS

Activated partial thromboplastin time (APTT), D-dimer, and fibrinogen levels were evidently higher in the severe group than in the non-severe group. Among non-severe COVID-19 patients, the aforementioned indicators depicted increasing trends, but the fibrinogen level alone was higher than normal. However, in severe COVID-19 patients, values of all three indices were higher than normal. In severe COVID-19 patients, fibrinogen and D-dimer were correlated with several inflammation indices during the early stage of the disease. However, no correlation between fibrinogen and inflammatory factors was observed in non-severe COVID-19 patients at any time point.

DISCUSSION

Results revealed that the hypercoagulability tendency of severe COVID-19 patients was more evident. The relationship between coagulation function and inflammatory factors showed that changes in coagulation function in severe COVID-19 patients may be related to abnormal increase in inflammatory factors at an early stage; however, in non-severe COVID-19 patients, there might be other factors leading to abnormal coagulation.

CONCLUSION

Inflammatory factors were not the only cause of abnormal coagulation function in COVID-19 patients.

The incidence of pulmonary thromboembolism in COVID-19 patients admitted to the intensive care unit: a meta-analysis and meta-regression of observational studies

Objectives

Coronavirus disease 2019 (COVID-19) infection is associated with a prothrombotic state. We performed a meta-analysis of proportions to estimate the weighted average incidence of pulmonary thromboembolism (PTE) in COVID-19 patients who were admitted to the intensive care unit (ICU).

Methods

We searched various medical databases for relevant studies from 31 December 2019 till 30 September 2020. We included observational studies that reported the incidence of PTE in COVID-19 patients admitted to the ICU. We extracted data related to study characteristics, patient demographics, and the incidence of PTE. Risk of bias was assessed by using the ROBINS-I tool. Statistical analysis was performed with R 3.6.3.

Results

We included 14 studies with a total of 1182 patients in this study. Almost all patients in this meta-analysis received at least prophylactic anticoagulation. The weighted average incidence of PTE was 11.1% (95% CI 7.7% to 15.7%, I² = 78%, Cochran’s Q test P < 0.01). We performed univariate and multivariate meta-regression, which identified the proportion of males as a significant source of heterogeneity (P = 0.03, 95% CI 0.00 to − 0.09)

Conclusion

The weighted average incidence of PTE remains high even after prophylactic anticoagulation. PTE is a significant complication of COVID-19 especially in critically ill patients in the ICU.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-021-00535-x.

Gender-associated difference following COVID-19 virus infection: Implications for thymosin alpha-1 therapy

Gender influences clinical presentations, duration and severity of symptoms, and therapy outcome in coronavirus disease 2019 (COVID-19) infection. Whether the immune response to Tα1 treatment for SARS-CoV-2 differs between the sexes, and whether this difference explains the male susceptibility to COVID-19, is unclear. This study aimed to investigate the efficiency and safety of Tα1 treatment and provide a basis for practically identifying gender differences characteristics and features of COVID-19. One hundred twenty-seven patients had COVID-19 symptoms and tested COVID19-positive (female 42.52%) in Wuhan union hospital were enrolled for medication. They were randomly divided into groups Control and Tα1 intervention. Seventy-eight patients received a subcutaneous injection of 1.6 mg Tα1, based on supportive treatment for 15 days. The control group included untreated 49 COVID19 patients closely matched for gender and age and received regular supportive treatment. In this retrospective analysis, we found that COVID-19-infected males reported more symptoms than COVID-19-infected females. A high degree of gender differences-related variability was observed in CRP and PCT levels and the cell counts of many lymphocyte subpopulations in the COVID-19 patients after Tα1 intervention. Levels of CRP and IL-6 were higher in Tα1-treated male group than Tα1-treated female group, while the level of PCT was significantly lower in Tα1-treated male group. Gender differences may be a factor in sustaining COVID-19 immunity responded to Tα1, male and female show statistically significant differences in relevance to cytokine production associated with the development of a more significant number of symptoms. This leaves the question of identifying gender-specific risk factors to explain these differences.

Clinical Experience, Pathophysiology, and Considerations in the Prophylaxis and Treatment of Hypercoagulopathy of COVID-19: A Review Study

Since the emergence of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic, an increasing number of reports and studies have tried to warn the medical community about the thrombotic complications of coronavirus disease 2019 (COVID-19). It is suggested that the hyperinflammatory response and endothelial injury, especially in patients with severe disease, lead to a hypercoagulable state. Sudden deaths occurring in some patients also point to fulminant arrhythmias and massive pulmonary embolism (PE). Several expert panels have published recommendations regarding the prophylaxis and treatment of such complications. Nonetheless, there are limited high-quality studies for evidence-based decision-making, and most of these recommendations have arisen from descriptive studies, and optimal anticoagulant agents and dosages are yet to be designated. The coagulopathy persists after the acute phase of the illness, and some panels recommend the continuation of deep vein thrombosis prophylaxis for several days after regaining the normal daily activities by the patient. Here, we review the incidence and possible mechanisms of thrombotic complications, and present a summary of the considerations for the prophylaxis and treatment of such complications in the adult population.

Factors associated with increased mortality in hospitalized COVID-19 patients

BACKGROUND

The rapid spread of the coronavirus disease 2019 (COVID-19) epidemic has significantly impacted global health. So far, the evidence regarding the risk factors that predict the outcomes of COVID-19 patients is limited. In this study, we identified several risk factors that are associated with increased mortality in COVID-19 patients.

METHODS

We performed a retrospective review of electronic medical records of the patients admitted with an initial diagnosis of COVID-19. We extracted several patient variables (including demographics, lab results, and pre-existing conditions) and examined for their association with increased mortality.

RESULTS

Of the 487 people included in the study, 340 survived and 147 expired. Significant differences existed in demographics and underlying comorbidities between the two groups. A higher proportion of patients were age 65 and older (87.76% vs 53.24%, p < 0.001), and were predominantly male (63.27% vs 52.94%, p = 0.0351). Multivariate analysis showed five variables to be the predictors for mortality: age ≥65 [OR = 3.87, 95% CI (2.01, 7.46), p < 0.001], initial presentation with dyspnea [OR = 1.71, 95% CI (1.03, 2.82), p = 0.037], history of cardiomyopathy [OR = 3.33, 95% CI (1.07, 10.41), p < 0.038], positive initial chest imaging findings [OR = 2.24, CI (1.26, 3.97), p = 0.006], and acute kidney injury (AKI) [OR = 3.33 CI (2.10, 5.28), P < 0.001].

CONCLUSION

Identifying COVID-19 patients with these characteristics may help guide the management and improve mortality.

A Case of COVID-19 Complicated by Venous Thromboembolism Despite Being on Prophylactic Anticoagulation

The coronavirus disease 2019 (COVID-19) presents with variable clinical syndromes, from asymptomatic disease to acute respiratory failure. Complications such as acute respiratory distress syndrome (ARDS), secondary infection, acute cardiac injury, liver failure, renal failure, coagulable disorders and in many cases, death have been recognized. Venous thromboembolism (VTE) was found to be present in up to one-third of critically ill COVID-19 patients. Our case demonstrated a patient with COVID-19 who developed a massive pulmonary embolism leading to cardiac arrest, despite having an initial normal D-dimer level, normal chest imaging, and while maintained on appropriate VTE prophylaxis during hospitalization.