Thrombosis research最新文献

Background

Incidence of central venous catheter (CVC)-related thrombosis in critically ill patients remains ambiguous and its association with potential hazardous sequelae unknown. The primary aim of the study was to evaluate the epidemiology of CVC-related thrombosis; secondary aims were to assess the association of catheter-related thrombosis with catheter-related infection, pulmonary embolism and mortality.

Methods

This was a single-center, prospective observational study conducted at a tertiary intensive care unit (ICU) in the Netherlands. The study population consisted of CVC placements in adult ICU patients with a minimal indwelling time of 48 h. CVC-related thrombosis was diagnosed with ultrasonography. Primary outcomes were prevalence and incidence, incidence was reported as the number of cases per 1000 indwelling days.

Results

173 CVCs in 147 patients were included. Median age of patients was 64.0 [IQR: 52.0, 72.0] and 71.1 % were male. Prevalence of thrombosis was 0.56 (95 % CI: 0.49, 0.63) and incidence per 1000 indwelling days was 65.7 (95 % CI: 59.0, 72.3). No association with catheter-related infection was found (p = 0.566). There was a significant association with pulmonary embolism (p = 0.022). All 173 CVCs were included in the survival analysis. Catheter-related thrombosis was associated with a lower 28-day mortality risk (hazard ratio: 0.39, 95 % CI: 0.17, 0.87).

Conclusion

In critically ill patients, prevalence and incidence of catheter-related thrombosis were high. Catheter-related thrombosis was not associated with catheter-related infections, but was associated with pulmonary embolism and a decreased mortality risk.

Introduction

Spontaneous echo contrast (SEC) and left atrial appendage thrombus (LAAT) increase the risk of stroke and its severity in patients with atrial fibrillation (AF). Formation of denser fibrin networks and impaired fibrinolysis are associated with stroke risk in AF. This study investigated whether the prothrombotic fibrin clot phenotype characterizes patients with SEC/LAAT.

Methods

We studied 139 anticoagulated patients with AF (median age, 70 years), who underwent transesophageal echocardiography (TEE). SEC and LAAT were recorded. We assessed plasma fibrin clot properties, i.e. permeability (K_s) and clot lysis time (CLT), von Willebrand Factor (vWF) antigen, endogenous thrombin potential (ETP), proteins involved in thrombosis and fibrinolysis, as well as plasma carbonylated protein content (PC).

Results

SEC/LAAT was identified in 36 subjects (25.9 %) and was associated with heart failure (HF), AF duration, higher CHA₂DS₂VASc score, N-terminal prohormone of brain natriuretic peptide, and growth differentiation factor 15. Patients with SEC/LAAT had lower K_s (−15 %) and prolonged CLT (+19 %), along with higher fibrinogen (+24 %), ETP (+3 %), and plasminogen activator inhibitor-1 antigen (+16 %) compared with the remainder. Thrombin-activatable fibrinolysis inhibitor antigen, plasminogen, α₂ − antiplasmin, and tissue plasminogen activator antigen were similar between the two groups. PC content was 50 % higher in SEC/LAAT and correlated with Ks (r = −0.47, p < 0.001) and CLT (r = 0.40, p < 0.001). On multivariate analysis, Ks, CLT, and PC levels, along with HF, remained independently associated with SEC/LAAT.

Conclusions

We demonstrated a formation of denser and poorly lysable fibrin networks in AF patients with SEC/LAAT despite anticoagulation. We suggest that this phenomenon is in part related to enhanced oxidative stress.

Background

Imaging evaluation of acute deep vein thrombosis (DVT) or post-thrombotic syndrome (PTS) in animal or clinical models is limited to anatomical assessment of the location and extent of thrombi. We hypothesize that Fe-MRI, used to evaluate macrophage content in other inflammatory diseases, can be useful to evaluate the thromboinflammatory features after DVT over time.

Methods

Nineteen wild-type CD-1 mice underwent surgical IVC ligation to induce DVT. Mice received either saline or 5 mg/kg of 14E11, a Factor XI inhibitor, before the procedure. Fe-MRI was performed on days 6–7 after ligation to evaluate thrombus volume, perfusion, and macrophage content via T₂-weighted images. Mice were euthanized at days 3–15 after surgery. The thrombi and adjacent vein walls were excised, weighed, formalin-fixed, and paraffin-embedded for immunohistological analysis. Specimens were stained with specific antibodies to evaluate macrophage content, collagen deposition, neovascularization, and recanalization. Significance was determined using the Mann-Whitney U or Student's t-test.

Results

After IVC-ligation in control mice, thrombus weights decreased by 59 % from day 3 to 15. Thrombus volumes peaked on day 5 before decreasing by 85 % by day 13. FXI inhibition led to reduced macrophage content in both thrombi (p = .008) and vein walls (p = .01), decreased thrombus volume (p = .03), and decreased thrombus mass (p = .01) compared to control mice. CCR2+ staining corroborated these findings, showing significantly reduced macrophage presence in the thrombi (p = .002) and vein wall (p = .002).

Conclusions

Fe-MRI T₂ relaxation times can be used to characterize and quantify post-thrombotic changes of perfusion, macrophage content, and thrombus volume over time in a surgical mouse model of venous thrombosis. This approach could lead to better quantification of in vivo inflammation correlating monocyte and macrophage content within resolving thrombi and veins and may serve as a useful tool for research and clinically in the evaluation of the post-thrombotic environment.

Gene therapy for hemophilia is a groundbreaking treatment approach with promising results and potential to reduce the burden of the disease. However, uncertainties remain, particularly regarding the liver side effects of AAV gene therapy, which are more common in hemophilia A.

Unlike some other diseases, such as spinal muscular atrophy, where the target cell for gene therapy is different from the one affected by side effects, hemophilia gene therapy operates within the same cellular domain-the hepatocyte. This overlap is challenging and requires a targeted strategy to mitigate the risks associated with liver injury, which often requires temporary immunosuppressive therapy. A comprehensive approach is essential to increase the efficacy of gene therapy and reduce the likelihood of hepatocyte damage. Key components of this strategy include a thorough pre-gene therapy assessment of liver health, careful post-gene therapy liver monitoring, and prompt therapeutic intervention for loss of transgene expression and liver injury. Collaboration between hematologists and hepatologists is essential to ensure a well-coordinated management plan for patients undergoing hemophilia gene therapy.

This review addresses the critical aspect of hepatic comorbidities in patients with hemophilia, emphasizing the need to identify and address these issues prior to initiating gene therapy. It examines the known mechanisms of liver damage and emphasizes the importance of liver monitoring after gene therapy. In addition, the review draws insights from experiences with other AAV-based gene therapies, providing valuable lessons that can guide hemophilia centers in effectively managing liver damage associated with hemophilia gene therapy.

Background

Intracerebral hemorrhage (ICH) of undetermined etiology occurs infrequently in young and middle-aged adults. We hypothesized that slight decreases in coagulation factors and formation of less compact fibrin clots prone to faster lysis predispose to this type of ICH.

Methods

We recruited 44 consecutive patients aged <50 years following ICH of unknown cause at least 3 months since the event. Subjects free of ICH (n = 47) matched for age, sex, BMI, and hypertension served as the control group. We assessed plasma fibrin clot permeability, turbidity and fibrinolytic capacity, along with thrombin generation, coagulation factors (F) II, FV, FVII, FVIII, FIX, FX, FXI, antithrombin, and fibrinolysis proteins.

Results

ICH patients (median age 41 years, 45.5 % women) had 8.4 % lower FII (p = 0.0001) and 10.1 % lower FVII activity (p = 0.0003), 9.4 % higher antithrombin activity (p = 0.0004) and 13.5 % lower platelet count (p = 0.02). Other factors and thrombin generation did not differ between the two groups. The ICH survivors were characterized by impaired fibrin polymerization reflected by 10.1 % longer lag phase of the turbidimetry curve (p = 0.0002), decreased fiber density indicated by 11.8 % lower maximum absorbance (p = 0.004), as well as 11.1 % shorter clot lysis time (p = 0.014) and 10.0 % faster increase of maximal D-Dimer levels (p = 0.000001).

Conclusions

We demonstrated a prohemorrhagic fibrin clot phenotype, along with lower FII, FVII and higher antithrombin activity in adults below 50 years of age who suffered from ICH of unknown cause, which might indicate novel mechanisms contributing to ICH in younger individuals.

Background

Von Willebrand Disease (VWD) is the most common inherited bleeding disorder. VWD is characterized by an abnormal quantity or quality of von Willebrand Factor (VWF). Anemia is often found at presentation for a bleeding disorder evaluation due to chronic blood loss.

Objectives/Hypothesis

We hypothesized that anemia is associated with elevations in both VWF and factor VIII (FVIII) over baseline. We also hypothesized that obesity would be associated with increased levels of VWF.

Methods

We conducted a single-center review of the electronic health record for patients that had proximal von Willebrand profiles and Hb data.

Results

We identified 4552 unique subjects with VWF studies and a CBC within 24 h. We found that decreasing hemoglobin inversely correlated with VWF antigen, VWF ristocetin cofactor activity, and FVIII activity. We also found that obesity and Black race were independently associated with increased VWF antigen, activity, and FVIII activity. Hb, race, and body mass index (BMI) continued to be determinants of VWF and FVIII levels in multivariable analysis.

Conclusion

Our study demonstrates that anemia, race, and BMI were found to be associated with elevation of VWF antigen, VWF activity, and FVIII levels. As many individuals with anemia present for evaluation for a bleeding disorder, these variables need to be considered.

Key points

- Anemia was found to be associated with elevation of VWF antigen, VWF activity and FVIII levels.

- Testing von Willebrand factor at times of anemia may mask a diagnosis of von Willebrand Disease.

Antiplatelet therapy, the gold standard of care for patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI), is one of the therapeutic approaches most associated with the development of adverse drug reactions (ADRs). Although numerous studies have shown that pharmacological intervention based on a limited number of high-evidence variants (primarily CYP2C19*2 and *3) can reduce the incidence of major adverse cardiovascular events (MACEs), ADRs still occur at variable rates (10.1 % in our case) despite personalized therapy.

This study aimed to identify novel genetic variants associated with the endpoint of MACEs 12 months after PCI by designing and analyzing a targeted gene panel. We sequenced 244 ACS-PCI-stent patients (109 with event and 135 without event) and 99 controls without structural cardiovascular disease and performed an association analysis to search for unexpected genetic variants.

No single nucleotide polymorphisms reached genomic significance after correction, but three novel variants, including ABCA1 (rs2472434), KLB (rs17618244), and ZNF335 (rs3827066), may play a role in MACEs in ACS patients. These genetic variants are involved in regulating high-density lipoprotein levels and cholesterol deposition, and as they are regulatory variants, they may affect the expression of nearby lipid metabolism-related genes. Our findings suggest new targets (both at the gene and pathway levels) that may increase susceptibility to MACEs, but further research is needed to clarify the role and impact of the identified variants before these findings can be incorporated into the therapeutic decision-making process.

Background

The prevalence of anticoagulation treatment is increasing as an aging global population faces a high burden of cardiovascular comorbidities. Direct oral anticoagulants, including factor Xa inhibitors (FXai), are replacing vitamin K antagonists as the most commonly prescribed treatment for reducing risk of thrombotic events. While the risk of FXai-associated spontaneous bleeds is established, less is understood about their management and the effect of treatment on clinical and patient-reported outcomes. The primary objectives of the REVERXaL study are to describe patient characteristics, health care interventions during the acute-care phase, in-hospital outcomes, and associations between timing of reversal/replacement agent administration and in-hospital outcomes. Secondary/exploratory objectives focus on clinical assessments and patient-reported outcome measures (PROMs) at 30 and 90 days.

Methods

REVERXaL is a multinational, observational study of hospitalized patients with FXai-associated major bleeds in Germany, Japan, the United Kingdom, and the United States. The study includes 2 cohorts of approximately 2000 patients each. Cohort A is a historic cohort for whom medical chart data will be collected from hospitalization to discharge for patients admitted for major bleeds during FXai use within 2 years prior to enrollment of Cohort B. Cohort B will prospectively enroll patients administered any reversal/replacement agent during hospitalization to manage FXai-associated major bleeds and will include the collection of clinical outcomes and PROMs data over 3 months.

Conclusions

REVERXaL will generate insights on patient characteristics, treatment approaches, and associated outcomes in patients hospitalized with FXai-associated major bleeds. These data may inform clinical practice and streamline treatment pathways in this population.

Registration

URL: https://www.clinicaltrials.gov; unique identifier: NCT06147830.

Background

Patients with suspected deep vein thrombosis (DVT) are typically referred to the emergency department for immediate evaluation. To enhance efficiency, our hospital implemented a regional, general practitioner (GP)-driven DVT care pathway, deferring diagnostic evaluation to a scheduled outpatient DVT clinic appointment the following day. Patients receive a single dose anticoagulant from their GP to prevent thrombosis progression while awaiting diagnostic workup. This prospective study aimed to evaluate the safety and patient preferences regarding the DVT care pathway and the type of single dose anticoagulant (low-molecular-weight heparin (LMWH) vs. direct oral anticoagulant (DOAC)).

Methods

Patients enrolled in the DVT care pathway between June 2021 and July 2023 were eligible. Until July 2022, LMWH was administered, and thereafter, the protocol recommended DOAC as the single dose anticoagulant. Patients completed questionnaires, incorporating patient-reported outcome and experience measures (PROMs/PREMs), during their DVT clinic visit and after five days. The primary endpoint was bleeding events within 72 h of receiving the single dose anticoagulant.

Results

Of 460 included patients, 229 received LMWH and 231 received DOAC as the single dose anticoagulant. DVT was confirmed in 24.8 % of patients. No major or clinically relevant non-major bleeding were reported. LMWH was associated with more minor bleedings (22.3 % vs. DOAC 13.4 %), primarily attributed to injection site hematomas. Patients reported high satisfaction with the DVT care pathway (96.5 %) and generally preferred DOAC over LMWH.

Conclusion

Deferring diagnostic evaluation for DVT using a single dose of either LMWH or DOAC in a real-world population is deemed safe. Considering practical advantages, patient preferences, and fewer skin hematomas, we favor DOACs as the single dose anticoagulant in this care pathway.