Finding the origin of pulmonary emboli with a total-body magnetic resonance direct thrombus imaging technique

Isolated distal deep vein thrombosis associated with adenomyosis: Case report and literature review

While adenomyosis is commonly associated with a mild risk of thrombotic complications, the presence of additional thrombophilia factors can increase this risk, particularly in individuals with severe symptoms and elevated CA125 levels.

Case Report: In situ pulmonary artery thrombosis in a 12-year-old girl classified as systemic lupus erythematosus

In situ pulmonary artery thrombosis (ISPAT) is a relatively rare but potentially life-threatening complication of systemic lupus erythematosus (SLE) in children. We report the case of a 12-year-old girl who presented with fever, chest pain, and dyspnea. Immune thrombocytopenia was identified due to purpura and menorrhagia 3 months before presentation with a lowest platelet count of 12 × 109/L. The sudden onset of fever, chest pain, and dyspnea were misdiagnosed as hyperinflammatory responses caused by pneumonia; these symptoms ameliorated with glucocorticoid and antibiotic treatment. The reappearance of symptoms after dose reduction of glucocorticoids and the observation of bloody bronchoalveolar lavage fluid necessitated further evaluation. Pulmonary artery thrombosis/embolism was identified using computed tomography pulmonary angiography and high D-dimer quantitative level of 4,118 μg/L (normal <252 μg/L). Ultrasonography of the deep and superficial veins of both lower limbs and renal veins revealed no thrombosis, suggesting the diagnosis of ISPAT. Further etiological evaluation revealed positive antinuclear antibodies, lupus anticoagulant, and anti-SSA antibodies, confirming SLE. Repeated normal urine analysis indicated that lupus nephritis was unlikely. Further, the negative anticardiolipin and anti-β2 glycoprotein antibodies and temporary positive lupus anticoagulant suggested that antiphospholipid syndrome was unlikely. The patient received anticoagulants, glucocorticoids, hydroxychloroquine, and mycophenolate therapy. Her symptoms gradually improved, and she was discharged. At the 1-month follow-up, the thrombosis had resolved. During the 1-year follow-up, her condition remained well without SLE relapse. Our experience with this case emphasizes searching for SLE in the case of ISPAT and pulmonary hemorrhages. ISPAT can occur in children with SLE and may be caused by hyperinflammatory response during SLE flare.

Mechanisms and Prediction of Ischemic Stroke in Atrial Fibrillation Patients

Atrial fibrillation (AF) is the most common arrhythmia in adults worldwide and represents an important burden for patients, physicians, and healthcare systems. AF is associated with substantial mortality and morbidity, due to the disease itself and its specific complications, such as the increased risk of stroke and thromboembolic events associated with AF. The temporal relation between AF episodes and stroke is nonetheless incompletely understood. The factors associated with an increased thromboembolic risk remain unclear, as well as the stroke risk stratification. Therefore, in this review, we intend to expose the mechanisms and physiopathology leading to intracardiac thrombus formation and stroke in AF patients, together with the evidence supporting the causal hypothesis. We also expose the risk factors associated with increased risk of stroke, the current different risk stratification tools as well as future prospects for improving this risk stratification.

Spectrum of Thrombotic Complications in Fatal Cases of COVID-19: Focus on Pulmonary Artery Thrombosis In Situ

COVID-19-related thrombosis affects the venous and arterial systems. Data from 156 autopsies of COVID-19 patients were retrospectively analyzed to investigate the pattern of thrombotic complications and factors associated with pulmonary artery thrombosis and thromboembolism. Thrombotic complications were observed in a significant proportion (n = 68, 44%), with pulmonary artery thrombosis the most frequently identified thrombotic event (42, 27%). Multivariate analysis revealed that the length of hospital stay (OR 1.1, p = 0.004), neutrophil infiltration in the alveolar spaces (OR 3.6, p = 0.002), and the absence of hyaline membranes (OR 0.1, p = 0.01) were associated with thrombotic complications. Neutrophil infiltration in the alveolar spaces (OR 8, p < 0.001) and the absence of hyaline membranes (OR 0.1, p = 0.003) were also independent predictors of pulmonary artery thrombosis. The association of pulmonary artery thrombosis with an absence of hyaline membranes suggests it occurs later in the course of COVID-19 infection. As neutrophil infiltration in the alveolar spaces may indicate bacterial infection, our studies suggest the consideration of bacterial infections in these critically ill patients.

Hand grip strength in venous thromboembolism: risk of recurrence and mortality

Background

There is limited information on the relationship between muscle strength and recurrence and mortality after incident venous thromboembolism (VTE).

Objectives

To investigate whether weak hand grip strength (HGS) was associated with risk of recurrence and mortality in patients with VTE recruited from the general population.

Methods

Participants from the Tromsø Study with a first-time VTE (n = 545) were included, and all VTE recurrences and deaths among the participants were recorded in the period 1994 to 2020. Weak HGS was defined as lowest 25th percentile of the general population, and incidence rates for VTE recurrence and mortality according to weak vs normal (>25th percentile) HGS, with 95% CIs, were estimated.

Results

There were 90 recurrences and 350 deaths during a median of 3.7 years of follow-up. The fully adjusted hazard ratio (HR) for overall VTE recurrence for those with weak HGS vs those with normal HGS was 2.02 (95% CI, 1.23-3.30). The corresponding HRs for recurrence were 2.22 (95% CI, 1.18-4.17) in patients with a first deep vein thrombosis and 1.60 (95% CI, 0.72-3.57) in patients with a first pulmonary embolism. The cumulative 1-year survival was 74.9% and 77.8% in those with weak and normal HGS, respectively. For overall mortality after incident VTE, the fully adjusted HR for those with weak HGS was 1.34 (95% CI, 1.04-1.72).

Conclusion

Weak HGS was associated with an increased risk of recurrent VTE, and the association appeared to be particularly pronounced after incident deep vein thrombosis. There was a slightly lower survival probability among those with weak HGS than among those with normal HGS.

Long-term ambient air pollution and venous thromboembolism in a population-based Swedish cohort

Air pollution is a major contributor to the global burden of disease and has been linked to several diseases and conditions, including cardiovascular disease. The biological mechanisms are related to inflammation and increased coagulability, factors that play an important role in the pathogenesis of venous thromboembolism (VTE, i.e., deep vein thrombosis or pulmonary embolism). This study investigates if long-term exposure to air pollution is associated with increased VTE incidence. The study followed 29 408 participants from the Malmö Diet and Cancer (MDC) cohort, which consists of adults aged 44-74 recruited in Malmö, Sweden between 1991 and 1996. For each participant, annual mean residential exposures to particulate matter <2.5 μg (PM_2.5) and <10 μg (PM₁₀), nitrogen oxides (NO_x) and black carbon (BC) from 1990 up to 2016 were calculated. Associations with VTE were analysed using Cox proportional hazard models for air pollution in the year of the VTE event (lag0) and the mean of the prior 1-10 years (lag1-10). Annual air pollution exposures for the full follow-up period had the following means: 10.8 μg/m³ for PM_2.5, 15.8 μg/m³ for PM₁₀, 27.7 μg/m³ for NO_x, and 0.96 μg/m³ for BC. The mean follow-up period was 19.5 years, with 1418 incident VTE events recorded during this period. Exposure to lag1-10 PM_2.5 was associated with an increased risk of VTE (HR 1.17 (95%CI 1.01-1.37)) per interquartile range (IQR) of 1.2 μg/m³ increase in PM_2.5 exposure. No significant associations were found between other pollutants or lag0 PM_2.5 and incident VTE. When VTE was divided into specific diagnoses, associations with lag1-10 PM_2.5 exposure were similarly positive for deep vein thrombosis but not for pulmonary embolism. Results persisted in sensitivity analyses and in multi-pollutant models. Long-term exposure to moderate concentrations of ambient PM_2.5 was associated with increased risks of VTE in the general population in Sweden.

To Study the Correlation of Clinical Severity and Cytokine Storm in COVID-19 Pulmonary Embolism Patients by Using Computed Tomography Pulmonary Angiography (CTPA) Qanadli Clot Burden Scoring System

BACKGROUND

Pulmonary embolism (PE) is a fatal form of venous thromboembolism (VTE), with an overall untreated mortality of up to 30%. Greater than 50% of patients with lower extremity proximal DVT have concurrent PE at presentation. VTE has been seen in up to one-third of patients with COVID-19 infections requiring intensive care unit (ICU) admission. The objective of this study is to determine the correlation between CT pulmonary angiography, pulmonary embolism clot burden, and the Qanadli scoring system with clinically severe COVID-19 pneumonia and cytokine storm.

MATERIAL AND METHOD

153 COVID-19 hospitalized patients who underwent CT pulmonary angiography (CTPA) for likely PE on pretest probability modified Wells criteria were enrolled. COVID-19 pneumonia was classified as URTI (upper respiratory tract infection), mild, severe, and critical COVID pneumonia. For data analysis, we categorized into two groups: (1) the non-severe group included URTI and mild pneumonia, and (2) the severe group included severe and critical pneumonia. We used the Qanadli scoring system to assess the PE percentages of pulmonary vascular obstruction using CTPA.  Results: 41.8% (64) of COVID-19 patients were diagnosed with pulmonary embolism (PE) on CTPA. The majority of 51.6% of pulmonary vascular occlusions using the Qanadli scoring system for pulmonary embolism were at segmental arterial levels. Out of 104 COVID-19 cytokine storm patients, 45 (43%) were associated with pulmonary embolism. Overall, a 25% (16) mortality rate was observed in COVID-19 patients with pulmonary embolism.

DISCUSSION

The pathogenesis of hypercoagulability in COVID-19 may include direct endothelial cell invasion by the virus, microvascular inflammation, endothelial exocytosis, and endotheliitis. A meta-analysis of 71 studies to investigate the occurrence of PE on CTPA in COVID-19 patients found 48.6% in ICU settings and 65.3% of patients have clots in the peripheral pulmonary vasculature.

CONCLUSIONS

There is a significant correlation between pulmonary embolism and high clot burden Qanadli CTPA scores, as well as between the severity of COVID-19 pneumonia and mortality. The association between critically ill COVID-19 pneumonia and pulmonary embolism may result in higher mortality and a poor prognostic marker.

Thrombus in Transit Entrapped Within a Patent Foramen Ovale: Role of Multimodality Imaging

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TIT is a thrombus attached to any right heart structure.

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Multimodality imaging is essential in patients with TIT to rule out intracardiac shunt.

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PFO is the most common access of paradoxical embolization in patients with TIT.

Clinical Characteristics and Risk Factors for Early versus Late Pulmonary Embolism in Trauma Patients: A Retrospective, Observational Study

Background

We sought to evaluate the clinical characteristics and risk factors for early versus late pulmonary embolism (PE) in trauma patients.

Methods

This was a retrospective analysis of injured patients who presented with a confirmed PE between 2013 and 2019. Data were analysed and compared for patients with early PE (≤4 days) versus late PE (>4 days post-trauma).

Results

The study included 82 consecutive trauma patients with confirmed diagnosis of PE. The mean age of patients was 42.3 ± 16.2 years. The majority were males (79.3%) and the median time from injury to PE was 10 days. Of the PE cases, 24 (29.3%) had early PE, while 58 (70.7%) had late PE. The early PE group had higher rates of surgical intervention within 24 hours of admission than the late PE group (p = 0.001). Also, the rate of sub-segmental thrombi was significantly higher in the early PE group (p = 0.01). The late PE group sustained more moderate-to-severe injuries ie, GCS ED <13 (p = 0.03) and the median time from injury to PE diagnosis was 15 days (p = 0.001). After adjusting for the potential covariates, surgery within 24 hours of admission [adjusted odds ratio 37.58 (95% confidence interval 3.393-416.20), p = 0.003] was found to be significant independent predictor of early PE in trauma patients.

Conclusion

One-third of post-trauma PEs occurs early after trauma and the surgical intervention within the first 24 hours of admission is a major risk factor. A prospective study is needed to develop an objective risk assessment for the prevention and detection of early and late PE post-trauma.

Diagnostic accuracy of multiorgan point-of-care ultrasound compared with pulmonary computed tomographic angiogram in critically ill patients with suspected pulmonary embolism

BACKGROUND

Critically ill patients have a higher incidence of pulmonary embolism (PE) than non-critically ill patients, yet no diagnostic algorithm has been validated in this population, leading to the overuse of pulmonary artery computed tomographic angiogram (CTA). This study aimed to comparatively evaluate the diagnostic accuracy of point-of-care ultrasound (POCUS) combined with laboratory data versus CTA in predicting PE in critically ill patients.

METHODS

A prospective diagnostic accuracy study. Critically ill patients with suspected acute PE undergoing CTA were prospectively enrolled. Demographic and clinical data were collected from electronic medical records. Blood samples were collected, and the Wells and revised Geneva scores were calculated. Standardized multiorgan POCUS and CTA were performed. The discriminatory power of multiorgan POCUS combined with biochemical markers was tested using ROC curves, and multivariate analysis was performed.

RESULTS

A total of 88 patients were included, and 37 (42%) had PE. Multivariate analysis showed a relative risk (RR) of PE of 2.79 (95% CI, 1.61-4.84) for the presence of right ventricular (RV) dysfunction, of 2.54 (95% CI, 0.89-7.20) for D-dimer levels >1000 ng/mL, and of 1.69 (95% CI, 1.12-2.63) for the absence of an alternative diagnosis to PE on lung POCUS or chest radiograph. The combination with the highest diagnostic accuracy for PE included the following variables: 1- POCUS transthoracic echocardiography with evidence of RV dysfunction; 2- lung POCUS or chest radiograph without an alternative diagnosis to PE; and 3- plasma D-dimer levels >1000 ng/mL. Combining these three findings resulted in an area under the curve of 0.85 (95% CI, 0.77-0.94), with 50% sensitivity and 96% specificity.

CONCLUSIONS

Multiorgan POCUS combined with laboratory data has acceptable diagnostic accuracy for PE compared with CTA. The combined use of these methods might reduce CTA overuse in critically ill patients.

Exploratory Investigation of the Plasma Proteome Associated with the Endotheliopathy of Trauma

BACKGROUND

The endotheliopathy of trauma (EoT) is associated with increased mortality following injury. Herein, we describe the plasma proteome related to EoT in order to provide insight into the role of the endothelium within the systemic response to trauma.

METHODS

99 subjects requiring the highest level of trauma activation were included in the study. Enzyme-linked immunosorbent assays of endothelial and catecholamine biomarkers were performed on admission plasma samples, as well as untargeted proteome quantification utilizing high-performance liquid chromatography and tandem mass spectrometry.

RESULTS

Plasma endothelial and catecholamine biomarker abundance was elevated in EoT. Patients with EoT (n = 62) had an increased incidence of death within 24 h at 21% compared to 3% for non-EoT (n = 37). Proteomic analysis revealed that 52 out of 290 proteins were differentially expressed between the EoT and non-EoT groups. These proteins are involved in endothelial activation, coagulation, inflammation, and oxidative stress, and include known damage-associated molecular patterns (DAMPs) and intracellular proteins specific to several organs.

CONCLUSIONS

We report a proteomic profile of EoT suggestive of a surge of DAMPs and inflammation driving nonspecific activation of the endothelial, coagulation, and complement systems with subsequent end-organ damage and poor clinical outcome. These findings support the utility of EoT as an index of cellular injury and delineate protein candidates for therapeutic intervention.

Association Between Left Atrial Appendage Morphology and Function and the Risk of Ischaemic Stroke in Patients with Atrial Fibrillation

AF is the most common cardiac arrhythmia and has been identified as an independent risk factor for stroke. The European Society of Cardiology guidelines recommend a thromboembolic event risk assessment based on the CHA₂DS₂-VASc score. However, stroke also occurs in some patients with a low CHA₂DS₂-VASc score. Therefore, it is necessary to find new factors to improve thromboembolic risk stratification in AF patients. Over 90% of embolic strokes are caused by thrombi originating from the left atrial appendage (LAA). Thus, certain anatomical or functional parameters of the LAA could potentially be used to predict cardioembolic stroke. Studies have suggested that some of these factors, such as LAA morphology, number of LAA lobes, LAA dimensions, LAA volume, distance from the LAA ostium to the first bend of LAA, LAA orifice diameter, extent of LAA trabeculations, LAA takeoff, LAA flow velocity and LAA strain rate, are independently associated with a higher risk of stroke in a population of patients with AF and improve the performance of the CHA₂DS₂-VASc score. However, the results are conflicting and, so far, no new parameter has been added to the CHA₂DS₂-VASc score.

Negative Venous Leg Ultrasound in Acute Pulmonary Embolism: Prevalence, Clinical Characteristics, and Predictors

The purpose of this study was to investigate the prevalence, clinical characteristics, and predictors of negative venous leg ultrasound in acute pulmonary embolism (PE). We retrospectively analyzed a cohort of 168 patients with acute PE (median age 73 years, 44% women) evaluated with complete venous leg ultrasound. A multivariate logistic regression analysis was performed to identify the independent predictors of negative venous ultrasound in acute PE. Venous leg ultrasound was negative for deep venous thrombosis (DVT) in 78 patients (46.4%). Patients with negative venous ultrasound were less likely to have a history of DVT (7.7% vs. 20.0%, p = 0.0273) and had significantly lower D-dimer levels (median 2.5 vs. 6.2 mg/dL p < 0.0001). Negative venous ultrasound was more frequent in PE diagnosed with V/P-SPECT than in PE diagnosed with CT (66.2% vs. 34.0%, p < 0.0001). The prevalence of negative venous ultrasound increased with more peripherally located PE (29.5% for central/lobar, 43.1% for segmental, and 60.6% for subsegmental PE, p = 0.0049). For the multivariate analysis, a diagnosis of PE with V/P-SPECT rather than CT (OR 3.2, p = 0.0056) and lower D-dimer levels (OR 0.94, p = 0.0266) were independent predictors of negative venous ultrasound. In conclusion, venous leg ultrasound was negative for DVT in almost half of patients with acute PE. Negative venous ultrasound was more common in patients with no history of DVT, lower D-dimer levels, PE diagnosed with V/P-SPECT rather than CT, and more peripherally located PE.

Varicose Veins and Risk of Venous Thromboembolic Diseases: A Two-Sample-Based Mendelian Randomization Study

Background

Varicose veins are found to be associated with increased risk of venous thromboembolism (VTE) in many observational studies, but whether varicose veins are causally associated with VTE remains unclear. Therefore, we used a series of Mendelian randomization (MR) methods to investigate that association.

Methods

23 independent single-nucleotide polymorphisms (SNPs) for varicose veins were obtained from the Pan UK Biobank analysis. The outcomes datasets for deep vein thrombosis (DVT), pulmonary embolism (PE) and venous thromboembolism (VTE) were obtained from the FinnGen study. Before analysis, body mass index (BMI) and height were included as confounders in our MR model. Basic MR [inverse-variance weighted (IVW), weight-median, penalized weighted-median and MR-Egger methods] and MR-PRESSO were performed against each outcome using the whole SNPs and SNPs after excluding those associated with confounders. If causal associations were suggested for any outcome, a basic MR validation analysis, a multivariable MR analysis with BMI and height, a Causal Analysis Using Summary Effect estimates (CAUSE), and a two-step MR analysis with BMI and height, would follow.

Results

Using 21 qualified SNPs, the IVW method (OR: 1.173, 95% CI: 1.070-1.286, p < 0.001, FDR = 0.002), the weighted median method (OR: 1.255, 95% CI: 1.106-1.423, p < 0.001, FDR = 0.001), the penalized weighted median method (OR: 1.299, 95% CI: 1.128-1.495, p < 0.001, FDR = 0.001) and the MR-PRESSO (OR: 1.165, 95% CI: 1.067-1.273, p = 0.003, FDR = 0.009) suggested potential causal effect of varicose veins on DVT, but no cause effect was found for PE and VTE. Excluding SNPs associated with confounders yielded similar results. The causal association with DVT was validated using a self-reported DVT cohort (IVW, OR: 1.107, 95% CI: 1.041-1.178, p = 0.001). The causal association maintained after adjustment for height (OR = 1.105, 95% CI: 1.028-1.188, p = 0.007), BMI (OR = 1.148, 95% CI: 1.059-1.244, p < 0.001) and them both (OR = 1.104, 95% CI: 1.035-1.177, p = 0.003). The causal association also survived the strict CAUSE (p = 0.018). Finally, in two-step MR, height and BMI were found to have causal effects on both varicose veins and DVT.

Conclusion

Genetically predicted varicose veins may have a causal effect on DVT and may be one of the mediators of obesity and taller height that predispose to DVT.

Anatomic Variation of the Lateral Sinus in Patients With Idiopathic Intracranial Hypertension: Delineation With Black-Blood Contrast-Enhanced MRI

Objectives: The purpose of this study was to describe the peculiar anatomic variations in the lateral sinus and analyze the patterns of cerebrospinal fluid (CSF) drainage by using high-resolution (HR) black-blood (BB) contrast-enhanced magnetic resonance imaging (MRI) in patients with idiopathic intracranial hypertension (IIH).

Methods: Total 33 IIH patients who were found cerebral venous sinus stenosis (CVSS) by MR venography (MRV) were enrolled in this study. HR-BB contrast-enhanced MRI was used to assess the features of anatomical variations in transverse sinus and sigmoid sinus. The development of bilateral sinuses was firstly evaluated, including unilateral hypoplasia with contralateral dominance or bilateral balanced development. Then, four kinds of anatomical variations were eventually recorded, including circumscribed stenosis, arachnoid granulation (AG), fibrous septum (FS), and brain herniation (BH) into dural venous sinus (DVS).

Results: Bilateral venous drainage dysfunction was found in 30(90.9%) patients, whereas only 3(9.1%) patients presented unilateral venous drainage dysfunction. There was no difference in clinical symptoms between the two groups. The most common case is hypoplasia in unilateral sinus combined with anatomic variation in the contralateral dominant transverse sinus such as AG and BH into DVS. Total of 52 anatomic variations were finally found in bilateral sinuses in 33 enrolled patients, including 19(36.5%)AGs, 12(23.1%)FS, 7(13.5%) BH into DVS and 14(26.9%) circumscribed stenoses. Moreover, 41(62.1%) lateral sinuses showed enhancement in T1-weight-enhanced MRI.

Conclusions: Patients with CVSS almost had CSF outflow disorders, whatever bilateral equalization or unilateral hypoplasia with contralateral dominance. Four types of main anatomic variations, including circumscribed stenosis, AG, FS, and BH into DVS, caused venous reflux obstruction by elevating the intracranial press (ICP).

Plasma procoagulant phospholipid clotting time and venous thromboembolism risk

BACKGROUND

Negatively charged procoagulant phospholipids, phosphatidylserine (PS) in particular, are vital to coagulation and expressed on the surface membrane of extracellular vesicles. No previous study has investigated the association between plasma procoagulant phospholipid clotting time (PPLCT) and future risk of venous thromboembolism (VTE).

OBJECTIVES

To investigate the association between plasma PPLCT and the risk of incident VTE in a nested case-control study.

METHODS

We conducted a nested case-control study in 296 VTE patients and 674 age- and sex-matched controls derived from a general population cohort (The Tromsø Study 1994-2007). PPLCT was measured in platelet-free plasma using a modified factor Xa-dependent clotting assay. Logistic regression was used to estimate odds ratio (OR) with 95% confidence intervals (CI) for VTE with PPLCT modelled as a continuous variable across quartiles and in dichotomized analyses.

RESULTS

There was a weak inverse association between plasma PPLCT and risk of VTE per 1 standard deviation increase of PPLCT (OR 0.93, 95% CI 0.80-1.07) and when comparing those with PPLCT in the highest quartile (OR 0.89, 95% CI 0.60-1.30) with those in the lowest quartile. Subjects with PPLCT >95th percentile had substantially lowered OR for VTE (OR 0.35, 95% CI 0.13-0.81). The inverse association was stronger when the analyses were restricted to samples taken shortly before the event. The risk estimates by categories of plasma PPLCT were similar for deep vein thrombosis and pulmonary embolism.

CONCLUSION

Our findings suggest that high plasma PPLCT is associated with reduced risk of VTE.

[Pulmonary artery thrombosis: strategy of anticoagulation]

This review is devoted to the management of primary artery thrombosis (PAT). This disease was always considered only as a part of other venous thromboembolic events, in particular isolated pulmonary embolism (PE). Various studies show that PAT can develop as an independent event without concomitant damage to extra-vessels. PAT is characterized by own typical signs as primary and recurrent event that can determine special strategies of treatment. However, there are no studies devoted to this problem. We can only make some assumptions about PAT anticoagulation (AC) considering data on isolated PE comprising PAT. These data are available in PADIS-PE, ASPIRE, EINSTEIN-PE, Hokusai-VTE studies underlying modern guidelines of various societies. In the absence of studies on PAT AC these guidelines should regulate PAT AC approaches. AC is recommended in all cases of PE except isolated subsegmental PAT in ambulatory patients. Duration of AC depends on risk factors (major or minor). Anticoagulation for PAT following chronic inflammatory diseases is still disputable.

The Impact of SARS-CoV-2 Infection on Blood Coagulation and Fibrinolytic Pathways: A Review of Prothrombotic Changes Caused by COVID-19

The cardinal pathology of coronavirus disease 2019 (COVID-19) is a primary infection of pulmonary tract cells by severe acute respiratory syndrome coronavirus 2, provoking a local inflammatory response, often accompanied by cytokine storm and acute respiratory distress syndrome, especially in patients with severe disease. Systemic propagation of the disease may associate with thrombotic events, including deep vein thrombosis, pulmonary embolism, and thrombotic microangiopathy, which are important causes of morbidity and mortality in patients with COVID-19. This narrative review describes current knowledge of the pathophysiological mechanisms of COVID-19-associated coagulopathy, with focus on prothrombotic changes in hemostatic mediators, including plasma levels of clotting factors, natural anticoagulants, components of fibrinolytic system, and platelets. It will also highlight the central role of endothelial cells in COVID-19-associated coagulopathy. This narrative review discusses also potential therapeutic strategies for managing thrombotic complications. Awareness by medical experts of contributors to the pathogenesis of thrombotic events in COVID-19 is imperative to develop therapeutics not limited to regular anticoagulants. Instituting cooperation among medical personnel and researchers may lessen this novel virus' impact now, and in the event of recurrence.

COVID-19 Infection and Circulating Microparticles-Reviewing Evidence as Microthrombogenic Risk Factor for Cerebral Small Vessel Disease

Severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) due to novel coronavirus disease 2019 (COVID-19) has affected the global society in numerous unprecedented ways, with considerable morbidity and mortality. Both direct and indirect consequences from COVID-19 infection are recognized to give rise to cardio- and cerebrovascular complications. Despite current limited knowledge on COVID-19 pathogenesis, inflammation, endothelial dysfunction, and coagulopathy appear to play critical roles in COVID-19-associated cerebrovascular disease (CVD). One of the major subtypes of CVD is cerebral small vessel disease (CSVD) which represents a spectrum of pathological processes of various etiologies affecting the brain microcirculation that can trigger subsequent neuroinflammation and neurodegeneration. Prevalent with aging, CSVD is a recognized risk factor for stroke, vascular dementia, and Alzheimer's disease. In the background of COVID-19 infection, the heightened cellular activations from inflammations and oxidative stress may result in elevated levels of microthrombogenic extracellular-derived circulating microparticles (MPs). Consequently, MPs could act as pro-coagulant risk factor that may serve as microthrombi for the vulnerable microcirculation in the brain leading to CSVD manifestations. This review aims to appraise the accumulating body of evidence on the plausible impact of COVID-19 infection on the formation of microthrombogenic MPs that could lead to microthrombosis in CSVD manifestations, including occult CSVD which may last well beyond the pandemic era.

Atrial fibrillation and risk of venous thromboembolism: a Swedish Nationwide Registry Study

AIMS

Atrial fibrillation (AF) is associated with arterial thromboembolism, mainly ischaemic stroke, while venous thromboembolism (VTE) in AF is less well studied. The aim of this study, therefore, was to examine the relationship between AF and VTE, including pulmonary embolism (PE) and deep venous thrombosis (DVT).

METHODS AND RESULTS

AF cases without previous VTE, ischaemic stroke or pulmonary arterial hypertension were identified from the Swedish Inpatient Registry between 1987 and 2013 and compared to two population controls per case without AF matched for age, sex, and county with respect to the incidence of VTE, PE, and DVT. In total, 463 244 AF cases were compared to 887 336 population controls. In both men and women, VTE rates were higher among AF patients the first 30 days after an AF diagnosis [40.2 vs. 5.7 in men and 55.7 vs. 6.6 in women per 1000 person-years at risk, respectively; hazard ratios 6.64 (95% confidence interval, 5.74-7.69) and 7.56 (6.47-8.83)]; and then decreasing, simultaneously with an increasing number of AF patients being treated with oral anticoagulation. VTE risk was similar to controls after 9 months in men but remained slightly elevated in women.

CONCLUSION

AF is strongly associated with an increased risk of VTE during the first months after diagnosis. Introduction of anticoagulant therapy soon after AF diagnosis might reduce the risk of VTE as well as of ischaemic stroke.

Dysfibrinogenemia-Potential Impact of Genotype on Thrombosis or Bleeding

The congenital dysfibrinogenemias, most often associated with bleeding disorders, encompass mutations in the amino-terminal end of fibrinogen α-chain consisting of Gly17-Pro18-Arg19-Val20, known as knob A, which is a critical site for fibrin polymerization. Here we review the studies reporting dysfibrinogenemia due to mutations affecting fibrinogen knob A and identified 29 papers. The number of reports on dysfibrinogenemias related to residues Gly17, Pro18, Arg19, and Val20 is 5, 4, 18, and 2, respectively. Dysfibrinogenemias related to residues Gly17, Pro18, and Val20 are exclusively associated with bleeding tendency. However, the clinical picture associated with dysfibrinogenemia related to residue Arg19 varies, with most patients suffering from bleeding tendencies, but also transitory ischemic attacks and retinal thrombosis may occur. The reason for this variation is unclear. To elaborate the genotype-phenotype associations further, we studied a Danish family with knob A-related dysfibrinogenemia caused by the Aα Arg19Gly (p.Arg19Gly) mutation using whole-exome sequencing and fibrin structure analysis. Our family is the first reported carrying the p.Arg19Gly mutation combined with one or more single nucleotide polymorphisms (SNP)s in FGA, FGB, and/or FGG and increased fibrin fiber thickness and fibrin mass-to-length ratio suffering from pulmonary emboli, suggesting that compound genotypes may contribute to the thrombogenic phenotype of these patients. Our review, accordingly, focuses on significance of SNPs, compound genotypes, and fibrin structure measures affecting the genotype-phenotype associations in fibrinogen knob A mutations.

Protein expression profiling suggests relevance of noncanonical pathways in isolated pulmonary embolism

Patients with isolated pulmonary embolism (PE) have a distinct clinical profile from those with deep vein thrombosis (DVT)-associated PE, with more pulmonary conditions and atherosclerosis. These findings suggest a distinct molecular pathophysiology and the potential involvement of alternative pathways in isolated PE. To test this hypothesis, data from 532 individuals from the Genotyping and Molecular Phenotyping of Venous ThromboEmbolism Project, a multicenter prospective cohort study with extensive biobanking, were analyzed. Targeted, high-throughput proteomics, machine learning, and bioinformatic methods were applied to contrast the acute-phase plasma proteomes of isolated PE patients (n = 96) against those of patients with DVT-associated PE (n = 276) or isolated DVT (n = 160). This resulted in the identification of shared molecular processes between PE phenotypes, as well as an isolated PE-specific protein signature. Shared processes included upregulation of inflammation, response to oxidative stress, and the loss of pulmonary surfactant. The isolated PE-specific signature consisted of 5 proteins: interferon-γ, glial cell line-derived neurotrophic growth factor, polypeptide N-acetylgalactosaminyltransferase 3, peptidyl arginine deiminase type-2, and interleukin-15 receptor subunit α. These proteins were orthogonally validated using cis protein quantitative trait loci. External replication in an independent population-based cohort (n = 5778) further validated the proteomic results and showed that they were prognostic for incident primary isolated PE in individuals without history of VTE (median time to event: 2.9 years; interquartile range: 1.6-4.2 years), supporting their possible involvement in the early pathogenesis. This study has identified molecular overlaps and differences between VTE phenotypes. In particular, the results implicate noncanonical pathways more commonly associated with respiratory and atherosclerotic disease in the acute pathophysiology of isolated PE.

Venous Thromboembolic Disease in Chronic Inflammatory Lung Diseases: Knowns and Unknowns

Persistent inflammation within the respiratory tract underlies the pathogenesis of numerous chronic pulmonary diseases. There is evidence supporting that chronic lung diseases are associated with a higher risk of venous thromboembolism (VTE). However, the relationship between lung diseases and/or lung function with VTE is unclear. Understanding the role of chronic lung inflammation as a predisposing factor for VTE may help determine the optimal management and aid in the development of future preventative strategies. We aimed to provide an overview of the relationship between the most common chronic inflammatory lung diseases and VTE. Asthma, chronic obstructive pulmonary disease, interstitial lung diseases, or tuberculosis increase the VTE risk, especially pulmonary embolism (PE), compared to the general population. However, high suspicion is needed to diagnose a thrombotic event early as the clinical presentation inevitably overlaps with respiratory disorders. PE risk increases with disease severity and exacerbations. Hence, hospitalized patients should be considered for thromboprophylaxis administration. Conversely, all VTE patients should be asked for lung comorbidities before determining anticoagulant therapy duration, as those patients are at increased risk of recurrent PE episodes rather than DVT. Further research is needed to understand the underlying pathophysiology of in-situ thrombosis in those patients.

'Pulmonary thrombosis in situ': risk factors, clinic characteristics and long-term evolution

: Pulmonary embolism typically occurs from deep venous thrombosis (DVT). However, not always a DVT can be identified, and 'in situ' generation of pulmonary embolism has been considered, referred to in the literature as 'De novo pulmonary embolism' (DNPE). The objective of the study is to assess risk factors, comorbidities, clinic characteristics and long-term evolution of patients with pulmonary embolism in the absence of an identified source. Retrospective study of 280 patients with pulmonary embolism, 190 pulmonary embolisms with DVT group and 90 (32%) pulmonary embolism without DVT (DNPE group), admitted to an Internal Medicine Department of a tertiary hospital from January 2012 to December 2015. In the DNPE group, segmental and subsegmental arteries were more frequently affected (P = 0.01). As compared with pulmonary embolisms with DVT group: older age, female sex, sedentary lifestyle, diabetes mellitus, arterial hypertension, heart failure, respiratory infections and chronic obstructive pulmonary disease (COPD) were significantly more frequent in DNPE. In multivariate analysis, respiratory infection [odds ratio (OR) 12.2, P < 0.0001], COPD (OR 8.7, P < 0.0001) and female sex (OR 3.0, P = 0.003) were independently associated risk factors. Long-term mortality (median follow-up 15 months) was also higher in DNPE group (34 vs. 16%, P = 0.01). De novo pulmonary embolism occurred in 32% of cases of pulmonary embolisms and was more frequent in female and COPD patients or those with respiratory infections as compared with pulmonary embolisms in which DVT was identified as a source of embolism.

Chronic CT features in PE patients with co-existing DVT

OBJECTIVE

Clinical features may be different in patients with PE without co-existing DVT compared to those with PE with co-existing DVT. This prospective study aims to investigate the different clinical features between patients with isolated pulmonary embolism (PE) and those with PE associated with deep venous thrombosis.

METHOD

This is a prospective study conducted in 107 consecutive patients diagnosed with acute PE in the emergency department or other departments of Kırıkkale University Hospital. The diagnosis of PE was confirmed by computed tomography pulmonary angiography (CTPA), which was ordered on the basis of symptoms and findings. Bilateral lower extremity compression ultrasound with standard 7.5 MHz linear array probe was applied to all patients. According to compression ultrasound results, the patients were divided into two classes as with and without deep venous thrombosis. Embolism in the main or lobar pulmonary arteries were classified as central, and those found only in segmental or subsegmental arteries were classified as peripheral. Laboratory parameters and Oxygen saturation were assessed on admission.

RESULTS

67 of 107 (62.6%) patients with PE were isolated pulmonary embolism, and 40 (37.4%) were PE + DVT. Patients with PE with co-existing DVT have wider pulmonary artery, higher d-dimer and pro BNP level, and lower saturation than those with isolated pulmonary embolism. Central pulmonary embolism is more common in patients with deep vein thrombus than those without it. (87.5% (35/40) vs 32.8% (22/67),p = 0.001). 38.6% of central pulmonary embolism occur without deep vein thrombosis of the lower extremities. Patients with PE with co-existing DVT have 42.5% mosaic perfusion pattern,70% chronic infarct appearance such as linear band, pleural nodüle, %15.0 thickened, small arteries and, %12.5 shrunken complete artery occlusion, suggesting the chronic background.

CONCLUSION

PE patients with co-existing DVT are clinically more serious than those who do not have a DVT. An acute picture may be present in the chronic background in a significant proportion of patients with PE with co-existing DVT. In the presence of deep vein thrombosis, pulmonary embolism is usually central, but more than one-third of central pulmonary emboli occur without lower extremity deep vein thrombosis.

A whole blood thrombus mimic: Constitutive behavior under simple shear

Deep vein thrombosis and pulmonary embolism affect 300,000-600,000 patients each year in the US. To better understand the highly mechanical pathophysiology of pulmonary embolism, we set out to develop an in-vitro thrombus mimic and to test this mimic under large deformation simple shear. In addition to reporting on the mechanics of our mimics under simple shear, we explore the sensitivity of their mechanics to coagulation conditions and blood storage time, and compare three hyperelastic material models for their ability to fit our data. We found that thrombus mimics made from whole blood demonstrate strain-stiffening, a negative Poynting effect, and hysteresis when tested quasi-statically to 50% strain under simple shear. Additionally, we found that the stiffness of these mimics does not significantly vary with coagulation conditions or blood storage times. Of the three hyperelastic constitutive models that we tested, the Ogden model provided the best fits to both shear stress and normal stress. In conclusion, we developed a robust protocol to generate regularly-shaped, homogeneous thrombus mimics that lend themselves to simple shear testing under large deformation. Future studies will extend our model to include the effect of maturation and explore its fracture properties toward a better understanding of embolization.

Loose Fibrin Clot Structure and Increased Susceptibility to Lysis Characterize Patients with Central Acute Pulmonary Embolism: The Impact of Isolated Embolism

BACKGROUND

 Prothrombotic fibrin clot properties are associated with higher early mortality risk in acute pulmonary embolism (PE) patients. It is unknown whether different types of PE are associated with particular clot characteristics.

METHODS

 We assessed 126 normotensive, noncancer acute PE patients (median age: 59 [48-70] years; 52.4% males), who were categorized into central versus peripheral PE with or without concomitant deep vein thrombosis (DVT). Plasma fibrin clot permeability (K _s), clot lysis time (CLT), thrombin generation, platelet-derived markers, and fibrinolytic parameters were measured on admission. Plasma fibrin clot morphology was assessed by scanning electron microscopy (SEM).

RESULTS

 Patients with central PE (n = 76; 60.3%) compared with peripheral PE (n = 50; 39.7%) had 17.8% higher K _s and 14.3% shortened CLT (both p < 0.01 after adjustment for potential confounders including fibrinogen), with no differences between segmental and subsegmental PE. SEM analysis demonstrated larger fibrin fiber diameter and pore size in central PE compared with peripheral PE (both p < 0.01). For isolated PE, there was 23.3% higher K _s in central PE than in peripheral PE (n = 24; 19%) with no differences in other variables. Central PE combined with DVT (n = 45; 35.7%), as compared with central isolated PE (n = 31; 24.6%), was associated with shortened CLT (all p < 0.05).

CONCLUSION

 Our findings suggest that looser fibrin networks composed of thicker fibers with increased susceptibility to lysis characterize patients with central PE, suggesting that fibrin clot phenotype affects the size of thrombi occluding the pulmonary arteries, highlighting the role of fibrin structures in thrombus formation and stability.

Impact of atrial fibrillation/flutter on the in-hospital mortality of surgical patients - Results from the German nationwide cohort

BACKGROUND

To investigate the impact of atrial fibrillation/flutter (AF) on adverse in-hospital outcomes in hospitalized surgical patients.

METHODS

The nationwide German inpatient sample of the years 2005-2018 was used for this analysis. Surgical patients were stratified by AF and compared. Logistic regression models were used to investigate the impact of AF on in-hospital outcomes.

RESULTS

In total, 96,589,627 hospitalizations with surgery were included in the present analysis in Germany (2005-2018). Among these, 6,680,261 were additionally coded with AF (6.9%). In-hospital death rate was substantially higher in surgical patients with AF (6.3%) than without (1.1%). Proportion of surgical patients with AF increased from 4.8% in 2005 to 8.9% in 2018, whereas in-hospital mortality decreased from 7.6% to 5.6%. For further analysis of the year 2014, 7,043,514 hospitalized surgical patients (54.5% females, 31.6% aged ≥0 years) were included in the analysis. Of these, 546,019 patients (7.8%) were diagnosed with AF. Overall, 1.4% of the surgical patients and 5.8% of the surgical patients with AF died in-hospital. Surgical patients with coded AF were in median 20 years older (57.0 [37.0-72.0] vs. 77.0 [72.0-83.0] years, P < 0.001), had more often comorbidities such as heart failure (31.3% vs. 3.8%, P < 0.001). All-cause death (RR 6.14 (95%CI 6.05-6.22), P < 0.001) occurred more often in patients with AF than without. AF was an important predictor for in-hospital death (OR 1.58 [95%CI 1.56-1.61], P < 0.001) independent of age, sex and comorbidities.

CONCLUSIONS

The proportion of AF increased from 2005 to 2018 in surgical patients. AF was an independent risk factor for in-hospital death in these patients.

Massive pulmonary thromboembolism combined with transient thyrotoxicosis in an 18 year old girl

Background

Pulmonary thromboembolism (PTE) is thought to usually stem from deep vein thrombosis (DVT). However, evidence of DVT could not be found in many cases. Furthermore, transient thyrotoxicosis is a rare but potentially life–threatening emergency involving a systemic hypercoagulable state. We report on an 18 year-old-girl with transient thyrotoxicosis with massive PTE without DVT.

Case presentation

An 18-year-old girl was admitted to the hospital with syncope. Patient had no history of trauma, any known underlying disease or oral contraceptives use. Chest computed tomography (CT) showed massive PTE in both central pulmonary arteries and diffuse goiter. However, a low extremity Doppler sonogram did not detect DVT. To manage the PTE, we administered low molecular weight heparin. On the other hands, thyroid function test indicated a state of thyrotoxicosis. In addition, patient had a partial protein S deficiency but no other immunologic abnormality. Therefore, the patient was diagnosed with massive PTE, thyrotoxicosis, and partial protein S deficiency. Patient was discharged with oral warfarin and methimazole. A follow-up echocardiogram obtained 3 months after anticoagulation therapy demonstrated normal dimensions and systolic function. After thyrotoxicosis was treated with methimazole for a month, a euthyroid state was achieved and the goiter decreased to a normal size. The methimazole was gradually tapered off and stopped at 4 months. At a 6-month follow up visit, PTE and pulmonary hypertension had disappeared but the patient still had a partial protein S deficiency. We decided to stop all medication with careful monitoring. During a 4-year follow-up period after the episode, she was asymptomatic without any evidence of recurrent systemic thromboembolism or hyperthyroidism.

Conclusions

Early recognition and appropriate treatment of PTE combined with transient thyrotoxicosis were vital to preventing other complications.

A diagnosis of atrial fibrillation is not a predictor for pulmonary embolism

BACKGROUND AND OBJECTIVES

Atrial fibrillation causes stroke by embolization of blood clots from the left atrium. This suggests that it also can cause pulmonary embolism through embolization of thrombi from the right atrium. Our objective was to investigate if atrial fibrillation is an independent risk factor for pulmonary embolism.

METHOD

This is a retrospective registry study of a random sample of 1.5 million Swedish residents alive on January 1, 2010 (n = 1,442,028) who were followed until the end of 2017. Information about comorbidity, medication and outcomes was obtained from the Swedish national health registers. The endpoint was a first-time event of pulmonary embolism.

RESULTS

The group with atrial fibrillation was >25 years older (mean) than the group without and had almost three times higher incidence of pulmonary embolism (2.91 and 1.09 per 1000 year at risk, p < 0.001). After adjustment for age and other co-factors, atrial fibrillation without oral anticoagulant protection was not associated with increased risk for pulmonary embolism (HR 1.03, CI 0.94-1.13). Adjustment for the competing risk of dying showed similar results (sHR 0.99, CI 0.70-1.40). The higher rate of pulmonary embolism among patients with atrial fibrillation can be fully explained by differences in age and comorbidity.

CONCLUSION

A diagnosis of atrial fibrillation is not a predictor for pulmonary embolism.

Incidence of venous and arterial thromboembolic events reported in the tofacitinib rheumatoid arthritis, psoriasis and psoriatic arthritis development programmes and from real-world data

Objectives

Tofacitinib is a Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ulcerative colitis, and has been investigated in psoriasis (PsO). Routine pharmacovigilance of an ongoing, open-label, blinded-endpoint, tofacitinib RA trial (Study A3921133; NCT02092467) in patients aged ≥50 years and with ≥1 cardiovascular risk factor identified a higher frequency of pulmonary embolism (PE) and all-cause mortality for patients receiving tofacitinib 10 mg twice daily versus those receiving tumour necrosis factor inhibitors and resulted in identification of a safety signal for tofacitinib. Here, we report the incidence of deep vein thrombosis (DVT), PE, venous thromboembolism (VTE; DVT or PE) and arterial thromboembolism (ATE) from the tofacitinib RA (excluding Study A3921133), PsA and PsO development programmes and observational studies. Data from an ad hoc safety analysis of Study A3921133 are reported separately within.

Methods

This post-hoc analysis used data from separate tofacitinib RA, PsO and PsA programmes. Incidence rates (IRs; patients with events per 100 patient-years’ exposure) were calculated for DVT, PE, VTE and ATE, including for populations stratified by defined baseline cardiovascular or VTE risk factors. Observational data from the US Corrona registries (including cardiovascular risk factor stratification), IBM MarketScan research database and the US FDA Adverse Event Reporting System (FAERS) database were analysed.

Results

12 410 tofacitinib-treated patients from the development programmes (RA: n=7964; PsO: n=3663; PsA: n=783) were included. IRs (95% CI) of thromboembolic events among the all tofacitinib cohorts’ average tofacitinib 5 mg and 10 mg twice daily treated patients for RA, respectively, were: DVT (0.17 (0.09–0.27) and 0.15 (0.09–0.22)); PE (0.12 (0.06–0.22) and 0.13 (0.08–0.21)); ATE (0.32 (0.22–0.46) and 0.38 (0.28–0.49)). Among PsO patients, IRs were: DVT (0.06 (0.00–0.36) and 0.06 (0.02–0.15)); PE (0.13 (0.02–0.47) and 0.09 (0.04–0.19)); ATE (0.52 (0.22–1.02) and 0.22 (0.13–0.35)). Among PsA patients, IRs were: DVT (0.00 (0.00–0.28) and 0.13 (0.00–0.70)); PE (0.08 (0.00–0.43) and 0.00 (0.00–0.46)); ATE (0.31 (0.08–0.79) and 0.38 (0.08–1.11)). IRs were similar between tofacitinib doses and generally higher in patients with baseline cardiovascular or VTE risk factors. IRs from the overall Corrona populations and in Corrona RA patients (including tofacitinib-naïve/biologic disease-modifying antirheumatic drug-treated and tofacitinib-treated) with baseline cardiovascular risk factors were similar to IRs observed among the corresponding patients in the tofacitinib development programme. No signals of disproportionate reporting of DVT, PE or ATE with tofacitinib were identified in the FAERS database.

Conclusions

DVT, PE and ATE IRs in the tofacitinib RA, PsO and PsA programmes were similar across tofacitinib doses, and generally consistent with observational data and published IRs of other treatments. As expected, IRs of thromboembolic events were elevated in patients with versus without baseline cardiovascular or VTE risk factors, and were broadly consistent with those observed in the Study A3921133 ad hoc safety analysis data, although the IR (95% CI) for PE was greater in patients treated with tofacitinib 10 mg twice daily in Study A3921133 (0.54 (0.32–0.87)), versus patients with baseline cardiovascular risk factors treated with tofacitinib 10 mg twice daily in the RA programme (0.24 (0.13–0.41)).

Comorbidity and risk of venous thromboembolism after hospitalization for first-time myocardial infarction: A population-based cohort study

BACKGROUND

Myocardial infarction (MI) is a risk factor for venous thromboembolism (VTE). Although comorbidities affect MI prognosis, it is unclear whether they affect VTE risk after MI.

OBJECTIVES

We examined the impact of comorbidity on VTE risk after MI.

METHODS

We used nationwide population-based registries to identify first-time hospitalizations for MI and subsequent occurrence of VTE in Denmark (1995-2013). We included a comparison cohort from the general population matched 5:1 with MI patients by sex, age, and comorbidities. We computed 30-day and 1- to 12-month cumulative risks, rates, and hazard ratios of VTE. We also assessed the interaction between MI and comorbidity, defined as excess VTE risk in patients with both MI and comorbidity, by computing interaction contrasts and attributable fractions relating to the interaction.

RESULTS

Thirty-day and 1- to 12-month VTE risks were 0.6% and 0.5% in the MI cohort (n = 160 338) and 0.03% and 0.3% in the comparison cohort (n = 792 384). The 30-day hazard ratio for VTE in the MI cohort was 23 (95% confidence interval, 20-27), which decreased during 1-year follow-up. Thirty days after MI, interactions between MI and comorbidity accounted for 16% and 39% of VTE rates in MI patients with low-to-moderate and high comorbidity, respectively. The interactions were driven primarily by hemiplegia and cancer.

CONCLUSIONS

Thirty-day VTE risk was substantially increased after MI compared with the general population. Although the absolute VTE risk was low, comorbidity substantially increased this risk, especially hemiplegia and cancer. VTE prophylaxis might be indicated in such high-risk patients but warrants further investigation.

Pulmonary Artery Thrombosis: A Diagnosis That Strives for Its Independence

According to a widespread theory, thrombotic masses are not formed in the pulmonary artery (PA) but result from migration of blood clots from the venous system. This concept has prevailed in clinical practice for more than a century. However, a new technologic era has brought forth more diagnostic possibilities, and it has been shown that thrombotic masses in the PA could, in many cases, be found without any obvious source of emboli. Chronic obstructive pulmonary disease, asthma, sickle cell anemia, emergency and elective surgery, viral pneumonia, and other conditions could be complicated by PA thrombosis development without concomitant deep vein thrombosis (DVT). Different pathologies have different causes for local PA thrombotic process. As evidenced by experimental results and clinical observations, endothelial and platelet activation are the crucial mechanisms of this process. Endothelial dysfunction can impair antithrombotic function of the arterial wall through downregulation of endothelial nitric oxide synthase (eNOS) or via stimulation of adhesion receptor expression. Hypoxia, proinflammatory cytokines, or genetic mutations may underlie the procoagulant phenotype of the PA endothelium. Both endotheliocytes and platelets could be activated by protease mediated receptor (PAR)- and receptors for advanced glycation end (RAGE)-dependent mechanisms. Hypoxia, in particular induced by high altitudes, could play a role in thrombotic complications as a trigger of platelet activity. In this review, we discuss potential mechanisms of PA thrombosis in situ.

A proposal for staging COVID-19 coagulopathy

Coronavirus disease 2019 (COVID-19) is associated with significant hypercoagulability. However, despite prophylactic anticoagulation, critically ill patients with this condition develop thromboses. This forum discusses the lungs as the epicenter for the hemostatic issues, puts forward a proposal for staging COVID-19 coagulopathy based on available diagnostic markers, and suggest considering current and future treatment options based on these different stages.

Isolated Pulmonary Embolism Is Associated With a High Risk of Arterial Thrombotic Disease: Results From the VTEval Study

BACKGROUND

Isolated PE is associated with a higher burden of atherosclerotic disease than other manifestations of VTE.

RESEARCH QUESTION

We hypothesized that the presence of isolated PE may signal a chronically elevated risk of arterial thrombotic disease.

STUDY DESIGN AND METHODS

Data from the VTEval Study, a prospective cohort study enrolling individuals with clinical suspicion and imaging-based diagnosis or exclusion of VTE, were analyzed. Patients with PE received whole-leg ultrasonography to assess presence of DVT. Regularized logistic regression identified features that discriminate between isolated PE and other VTE phenotypes at clinical presentation. Survival analyses were performed to evaluate the crude and adjusted 3-year risks of arterial thrombotic disease, recurrent VTE, and death.

RESULTS

The sample comprised 510 patients. Isolated PE patients (n = 63) had a distinct clinical profile from patients with other VTE phenotypes (n = 447). COPD, peripheral artery disease, atrial fibrillation, and coronary artery disease were significantly more prevalent among patients with isolated PE. Isolated PE patients had significantly higher risk (incidence rate ratio vs DVT-associated PE, 3.7 (95% CI, 1.3-10.8, P = .009); vs isolated DVT, 4.8 (1.7-14.3, P = .001) of arterial thrombotic events (ie, myocardial infarction, stroke/transient ischemic attack). After adjustment for clinical profile and medication intake, the risk of arterial thrombotic events for patients with isolated PE remained quadruple that of other VTE phenotypes (hazard ratio [HR], 3.8 [1.3-10.9], P = .01).

INTERPRETATION

Patients with isolated PE are at higher risk for arterial thrombosis and may require screening for arterial disease and development of novel therapeutic strategies.

CLINICAL TRIAL REGISTRATION

NCT02156401.

Pulmonary embolism associated with transfusion after severe post-partum haemorrhage: is less more?

BACKGROUND

Transfusion of red blood cells is associated with superficial vein thrombosis (SVT) and venous thromboembolism (deep vein thrombosis and/or pulmonary embolism, VTE). The present study investigated the prevalence of SVT and VTE in women transfused in the peri-partum period.

MATERIALS AND METHODS

We carried out an observational study in a tertiary level obstetrics department in the Apulia Region of Southern Italy to investigate VTE in women transfused during or after labour. The study included all women who delivered between January 1st and November 30th, 2018. A thrombotic event was defined as an admission with an ICD-9 code of SVT and VTE as a primary or secondary diagnosis. Maternal "near-miss" rate, as defined by the World Health Organization, was calculated and outcome of transfused women was recorded.

RESULTS

From January 1st to November 30th, a total of 1,028 women delivered, 39% of them by caesarean section (CS). One-hundred and thirty-two women (12.8%) had been classified with one or more complication codes. Most complications occurred in women who underwent CS with an odds ratio (OR) of 7.0 (95% CI: 4.0-12.5; p=0.000). Twelve women (1.2%) were transfused in the peri-partum period, 7 of them had delivered by CS. The only thrombotic events recorded in the entire cohort of 1,028 patients were isolated pulmonary embolisms observed in 2 out of 12 transfused women. Overall, patients had received a mean of 7.5 units of packed red blood cells (1 patient also received 7 plasma units, while 1 patient also received 1 platelet unit). Consequently, the near-miss rate was 2.0/1,000 deliveries, which is not significantly different from that expected in Italy and in high-income countries.

CONCLUSIONS

Pulmonary embolism is a life-threatening complication, which can be associated with transfusion in the peri-partum period.

Pulmonary embolism location is associated with the co-existence of the deep venous thrombosis

: Multiple studies have shown that in approximately half of individuals with pulmonary embolism (PE), the deep venous thrombosis (DVT) is not evident at the moment of PE diagnosis. The underlying factors and the origin of PE in these patients are not completely understood: missed DVT, embolization of DVT in its entirety, or de-novo PE being possible explanations. The aim of this study was to evaluate the differences in PE patient with or without co-existing DVT. Sixty-three consecutive PE patients were included. Whole leg bilateral Doppler compression ultrasound was performed to all patients. The PE location and extension, C-reactive protein, platelet count, hemostatic markers FV, FVIII, FXIIIa, Fibrinogen, von Willebrand factor antigen, thrombomodulin were assessed. Thorough clinical assessment including echocardiography and pulmonary function tests were performed upon arrival and seven months later. The mean age of the patients was 57 years (SD 17.3) and 33 (52%) were women. Thirty-one patients (49.2%) had co-existing DVT. The presence of DVT was associated with the proximal location of the PE (100%), whereas none of the patients (n = 10) with exclusively peripheral PE had co-existing DVT. The PE extension, the measured hemostatic and inflammatory markers or the patient characteristics did not statistically differ between patients with isolated PE and PE with co-existing DVT. In roughly half of the PE patients no DVT could be detected. The location of the PE was associated with the presence of co-existing DVT. There were no differences in the PE extension, hemostatic markers or in the patient characteristic between patients with isolated PE or PE with co-existing DVT.

Atrial Fibrillation in Patients with Acute Pulmonary Embolism: Clinical Significance and Impact on Prognosis

Pulmonary embolism (PE) is one of the most common causes of cardiovascular death. The most often PE etiology is a deep vein thrombosis (DVT) of the lower extremities, but embolic material can arise in pelvic or upper extremity veins as well as in right heart chambers. There is growing number of evidences of atrial fibrillation (AF) involvement in PE. The presence of AF in patients with PE may be both the cause and the consequence of PE. The PE association with AF should be considered in patients without confirmed DVT and with history of AF, which itself is associated with prothrombotic state. The valuable diagnostic method is echocardiography that may bring the insight into source of embolic material. Another possible AF and PE association is the AF as a consequence of an abrupt increase in pulmonary vascular resistance due to the occlusion of the pulmonary vessels. Large-scale population-based studies have provided a considerable body of evidence on the involvement of PE in the onset of subsequent AF. Another important issue is the influence of AF on prognosis in patients with PE. Most investigators demonstrated a negative impact of AF on mortality. The main problem to resolve is whether AF is an independent mortality risk factor or whether it occurs as a result of comorbidities or the severity of a PE episode. Although the pathophysiological basis of this bidirectional relationship exists, many questions are still unresolved and require further studies, including the significance of paroxysmal AF accompanying an acute PE episode, the usefulness of PE risk scales in patients with concomitant AF, and the effect of anticoagulant treatment on PE and AF occurrence. Regardless of the type of AF, clinicians should be alert to the possibility of PE in patients with previous history of AF or presenting with new-onset AF.

Risk Factors for Postoperative Venous Thromboembolic Events in Patients Undergoing Lumbar Spine Surgery

STUDY DESIGN

Retrospective, database study.

OBJECTIVES

The aim of this study was to investigate incidence and risk factors associated with venous thromboembolic events (VTEs) after lumbar spine surgery.

METHODS

Patients who underwent lumbar surgery between 2007 and 2014 were identified using the Humana within PearlDiver database. ICD-9 (International Classification of Diseases Ninth Revision) diagnosis codes were used to search for the incidence of VTEs among surgery types, patient demographics and comorbidities. Complications including DVT and PE were queried each day from the day of surgery to postoperative day 7 and for periods 0 to 1 week, 0 to 1 month, 0 to 2 months, and 0 to 3 months postoperatively.

RESULTS

A total of 64 892 patients within the Humana insurance database received lumbar surgery between 2007 and 2014. Overall VTE rate was 0.9% at 1 week, 1.8% at 1 month, and 2.6% at 3 months postoperatively. Among patients that developed a VTE within 1 week postoperatively, 45.3% had a VTE on the day of surgery. Patients with 1 or more identified risk factors had a VTE incidence of 2.73%, compared with 0.95% for patients without risk factors (P < .001). Risk factors associated with the highest VTE incidence and odds ratios (ORs) were primary coagulation disorder (10.01%, OR 4.33), extremity paralysis (7.49%, OR 2.96), central venous line (6.70%, OR 2.87), and varicose veins (6.51%, OR 2.58).

CONCLUSIONS

This study identified several patient comorbidities that were independent predictors of postoperative VTE occurrence after lumbar surgery. Clinical VTE risk assessment may improve with increased focus toward patient comorbidities rather than surgery type or patient demographics.

Ischemic stroke risk estimation in patients without oral anticoagulation: an observational cohort study based on secondary data from Germany

BACKGROUND

Oral anticoagulants can cause potentially serious adverse events. Therefore, before prescribing oral anticoagulants for ischemic stroke prevention in patients with atrial fibrillation (AF), stroke risk assessment is required to identify patients that are likely to benefit from treatment. Current guidelines recommend the CHA2DS2-VASc-score for stroke risk assessment. The CHA2DS2-VASc-score is based on observational studies from different treatment settings and countries. As ischemic stroke risk differs by setting and region, the aim of this study is to estimate ischemic stroke risk (stratified by the CHA2DS2-VASc-score) for a broadly representative population with AF from southern Germany and compare them to results from previous studies.

METHODS

The study design is a retrospective cohort study on patients with atrial fibrillation based on secondary data. We calculated CHA2DS2-VASc-score based on patient's diagnoses recorded in the year 2014 and assessed outcomes in 2015-2016. The primary outcome is hospitalization for ischemic stroke. The secondary outome is hospitalizations for any thromboembolic event, including ischemic stroke, transient ischemic attack, peripheral arterial embolism, pulmonary embolism, and mesenterial embolism. We estimated the incidence rates of the outcomes (and corresponding 95%-confidence intervals) stratified by CHA2DS2-VASc-score.

RESULTS

The primary endpoint occurred in 961 of the 30,299 patients constituting the study population, resulting in a total incidence rate of 2.2 per 100 person-years. The secondary endpoint occurred in 1553 patients (3.6 per 100 person-years). Ischemic stroke rates stratified by the CHA2DS2-VASc-score tended to be lower than those reported previously. Thromboembolic event rates stratified tended to be similar to those reported previously.

CONCLUSIONS

Our results show that the performance of the CHA2DS2-VASc-score differs in the German population, as compared to internationally published data, with an overall trend towards lower risk of ischemic stroke in uncoagulated patients with AF. These results should not be practice changing, but they emphasize that stroke risk estimation in patients with atrial fibrillation should be further refined.

Diagnosing Recurrent DVT of the Leg by Two Different Non-Contrast-Enhanced Magnetic Resonance Direct Thrombus Imaging Techniques: A Pilot Study

Introduction  Magnetic resonance direct thrombus imaging (MRDTI) is a promising technique to improve the diagnostic management of patients with a suspected ipsilateral recurrent deep vein thrombosis (DVT) by direct visualization of a thrombus. Another magnetic resonance imaging (MRI) technique, T1-weighted turbo spin-echo spectral attenuated inversion recovery (TSE-SPAIR), has the potential to image a thrombus directly with a high spatial resolution as well. The main aim of this pilot study was to investigate if adding the TSE-SPAIR sequence to an MRDTI sequence performed in patients with suspected recurrent DVT may increase the diagnostic confidence of expert MRDTI readers.

Methods  Fifteen patients with suspected acute recurrent DVT were included in this study. The TSE-SPAIR sequence was scanned directly after the MRDTI scan but not used to guide clinical decision making, and both scans were adjudicated post hoc two times separately by three independent expert MRDTI readers. Diagnostic confidence was scored on a 4-point Likert scale: (1) poor (definite diagnosis impossible), (2) fair (evaluation of major findings possible), (3) good (definite diagnosis possible), and (4) excellent (exact diagnosis possible).

Results  The diagnostic confidence of expert readers increased when adding the TSE-SPAIR sequence on top of the MRDTI sequence from “good” (median, 3.0; interquartile range [IQR], 2.66–3.0) to “excellent” (median, 3.67; IQR 3.33–3.67; p  = 0.001). Evaluation of the scans in the reversed order 5 months after initial reading showed similar results. Diagnostic accuracy for proximal DVT of both scan techniques was good.

Conclusion  The extra TSE-SPAIR sequence may help increase diagnostic confidence of radiologists in cases of uncertain diagnosis in patients with suspected ipsilateral recurrent DVT.

Dietary intake of marine n-3 polyunsaturated fatty acids and future risk of venous thromboembolism

BACKGROUND

Studies on the association between long-chained n-3 polyunsaturated fatty acids (n-3 PUFAs) and risk of venous thromboembolism (VTE) are conflicting, potentially due to challenges related to assessment of n-3 PUFA intake and changes in diet during follow-up.

OBJECTIVES

To investigate whether dietary intake of marine n-3 PUFAs was associated with risk of incident VTE in a population-based cohort with repeated assessments of n-3 PUFA intake.

METHODS

We recruited 21 970 participants (after excluding 7570 with incomplete data) from the fourth (1994-1995) and sixth (2007-2008) surveys of the Tromsø Study, and recorded incident VTEs up to 2016. Intake of n-3 PUFAs was computed from self-reported consumption of fat and lean fish, fish spread, and supplements. Cox proportional hazards regression models with n-3 PUFA intake as a time-varying variable were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for VTE across quartiles (Q) of n-3 PUFA intake.

RESULTS

There were 541 incident VTEs during follow-up. Compared to Q1, subjects in Q2-4 had 22%-26% lower risk of VTE (HR Q2 0.74, 95% CI 0.57-0.96; HR Q3 0.77, 95% CI 0.59-0.99; HR Q4 0.78, 95% CI 0.61-1.00). The association was most pronounced for provoked VTE, particularly provoked pulmonary embolism (PE), with risk estimates of 0.42 (95% CI 0.25-0.72), 0.40 (95% CI 0.23-0.68), and 0.61 (95% CI 0.38-0.96) for Q2-4, respectively.

CONCLUSIONS

Dietary intake of marine n-3 PUFAs was associated with a lower risk of VTE, particularly provoked PE. The association displayed a threshold pattern and suggested a protective effect of an n-3 PUFA intake ≥4.7 g/week.