Anticoagulant Agents Research Articles

Percutaneous Endoscopic Gastrostomy: Insertion and Management

Percutaneous endoscopic gastrostomy (PEG) is the modality of choice for long-term enteral feeding in patients in whom oral intake is challenging. Compared with parenteral nutrition, gastrostomy feeding is the preferred choice for sustained nutritional support. Delivery of nutrients directly to the gastrointestinal tract and enhanced cellular immunity associated with this approach are clinically beneficial to patients. Endoscopic gastrostomy is favored for its high clinical success rates and economic advantages and is associated with minor discrepancies with regard to morbidity, mortality, and tube function compared with surgical gastrostomy. PEG procedures can be broadly classified into the pull- and push-types. Although PEG is a comparatively safe procedure, high risk of bleeding is a well-known complication of PEG placement, which necessitates prophylactic antibiotic therapy and careful periprocedural management in patients who receive antiplatelet and anticoagulant agents. Tube dislodgement, peristomal leakage, or infection following PEG placement may require tube replacement or removal. In this review, we investigated the concerns associated with early vs. delayed feeding in concordance with current guidelines. We also describe the indications for PEG tube insertion, post-procedural care strategies, and management of complications.

Pediatric Extracorporeal Membrane Oxygenation Anticoagulation and Monitoring: Where We Were and Where Are We Now?

Extracorporeal membrane oxygenation (ECMO) support in neonates and pediatric patients has continued to advance. In addition to technologic progress, there is a growing interest in the anticoagulation agents and laboratory monitoring strategies used in children requiring ECMO support. This review summarizes current available evidence and provides guidance for clinicians regarding anticoagulation agents and monitoring.

A Real World, Single-Centre Study of Young Adult Patients with Philadelphia Negative Myeloproliferative Neoplasms

Classical ‘Philadelphia negative’ myeloproliferative neoplasms (MPNs) are clonal haematopoietic disorders and include essential thrombocythaemia (ET), polycythaemia vera (PV) and myelofibrosis (MF). MPNs have a heterogenous phenotype with an inherent risk of thromboembolic and haemorrhagic complications, and risk of blastic transformation. MPNs are commonly diagnosed in the 6 th decade or later, although up to 20% of patients are diagnosed < 40 years. Current risk stratification and treatment guidance, however, is frequently extrapolated from older cohorts. Here, we present a comprehensive retrospective analysis of 107 MPN adolescent and young adult (AYA) patients diagnosed <40 years, representing 19.6% of the total outpatient MPN cohort at University College London Hospital. Median follow up was 78 months (range (r), 1 - 507). Table 1 displays clinicopathological details of the entire cohort. Median age at diagnosis was 32 years (r,13-40). There was a female preponderance (66%); 57.9% of patients were Caucasian. Most patients had a diagnosis of ET (57.9%), with 24.3% PV and 9.3% MF, respectively. The most common driver mutation was JAK2 V617F, observed in 60.7%, followed by CALR (15.9%) and MPL (1.9%); 17% of patients were classified as triple negative (TN). Where data was available (n=27), median variant allelic frequency (VAF) for JAK2 V617F was 19.7% (r, 4-75%) and for CALR 43% (r, 5.7 - 53). 9/107 (8.4%) of patients had additional pathogenic gene abnormalities, most commonly variants of NRAS (22.2%), TET2 (22.2%) and ASXL1 (22.2%). We observed a high thrombosis rate of 19.6% (21/107); the majority had a diagnosis of ET (61.9%).. In 80% of such cases, this was the heralding event leading to the MPN diagnosis. Venous thrombosis was more frequent than arterial thrombosis (68% vs 33%). In particular, there was a disproportionate number of venous thromboses at unusual sites including cerebral venous sinus and splanchnic venous thromboses, representing 40% and 33% of total events, respectively. Only 3 (2.8%) patients were found to have a co-existent thrombophilia. Younger age at diagnosis appeared to associate with a higher rate of thrombosis (60% in patients aged <20, 18.2% in patients aged 20-30, and 17.2% in patients aged 31-40). Thrombotic events were most common in those with a JAK2V617 mutation (23.4%), followed by those who were TN (20.0%). Only 5.9% of CALR mutated cases had a thrombotic event. In terms of cardiovascular risk factors, 13.0% (14/107) and 6.5% (7/107) of patients had diagnoses of hypertension and type 2 diabetes, respectively. Haemorrhagic events were reported in 8.4% (9/107) of patients; 3.7% (4/107) had grade 3 or 4 bleeding complications, requiring transfusion and/or surgical intervention. All who experienced haemorrhagic events were on treatment with an anti-platelet or anti-coagulant agent. 4.7% (5/107) were diagnosed with acquired von Willebrand's disease, of whom one experienced a grade 3 haemorrhagic event. No patients transformed during follow up. 33 patients reported pregnancies, with 7/33 (21%) reporting antenatal or perinatal medical complications. Over 50% (55/107) of patients were commenced on cytoreduction. Most common agents employed were pegylated interferon (45.5%; 25/55) and hydroxycarbamide (43.6%%; 24/55). No patients required combination therapy. 92/107 (86%) patients were treated with an antiplatelet agent and 9/107 (8.4%) were on anti-coagulant treatment with the majority (88.8%) receiving warfarin rather than a DOAC. AYA MPN patients have unique characteristics and heterogeneous clinico-biological features differentiating them from older MPN cohorts. Our data highlights a female preponderance, higher incidence of venous thrombosis (particularly atypical sites), and lower incidence of arterial thrombosis. Whilst traditionally younger patients are considered to have ‘low risk’ disease, this real-world study highlights a significant thrombosis rate of ~ 20% which may have associated morbidity considering the relatively longer duration of the disease course and need for cytoreductive therapy. Specific AYA MPN directed risk stratification and therapeutic algorithms are required to inform holistic and age-appropriate patient management.

The Choice of Anticoagulant at First Recurrence Does Not Alter the Risk for the Second Recurrence

Introduction : Venous thromboembolism (VTE), encompassing deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major public health hazard, with up to 30-50% of patients with unprovoked VTE experiencing a recurrent VTE event. These recurrent VTE events are associated with significant morbidity and mortality. However, transition strategies to second-line anticoagulation regimens following the first recurrence on anticoagulation have not been well studied. We sought to examine whether rates of the second VTE recurrence were different in those patients who changed their anticoagulation regimen from those who did not . Methods: With an IRB approval for the study, we created a database of all patients 18 years and older diagnosed with the first recurrent VTE at a large tertiary academic hospital between January 1, 2010, and December 31, 2019. The collected data was de-identified and compiled in a secure, standardized institutional database. We assessed the anticoagulation status at the time of and immediately following the first VTE recurrence, and identified patients who were switched to a different anticoagulant regimen. We used Fisher's exact test to evaluate proportions. Statistical significance was set at p<0.05. Results:We identified 138 patients with the first VTE recurrence. Of these patients, 114 (83%) developed DVT, 7 (5%) PE, and 17 (12%) both DVT and PE. Mean age was 63 years at the time of first VTE; 70 (51%) were female. Racial/ethnic representation was 84 (61%) White, 46 (33%) Black, and 133 (96%) non-Hispanic. The majority of patients had cardiovascular risk factors, including hypertension 80 (58%), hyperlipidemia 44 (32%), ordiabetes 40 (29%). Among 138 patients, 32 (23%) had active cancer, May-Thurner syndrome or inferior vena cava (IVC) atresia were reported in 13 (9%) of cases, and 21 (17%) underwent IVC filter placement at the time of the first VTE recurrence. The median follow-up time after diagnosis of a second VTE was 5 years. Following the first VTE recurrence, 19 (14%) of patients switched to a different anticoagulant agent, 7 (5%) had the dose of the anticoagulant adjusted, 1 (0.7%) was given a different INR target, and one had a change in the frequency of administration. The second VTE occurred in 49 (46%) patients who remained on the same anticoagulation regimen and in 3 (16%) who had the agent changed, in 5 who had dose of anticoagulant changed, in 1 (100%) each who had frequency or INR target changed. The association between unprovoked first VTE and the development of the second VTE was not significant (p= 0.85, Fisher's exact test). 49 (36%) of patients had at least one bleeding episode requiring the interruption of anticoagulation or hospitalization. Of those, 43 (88%) occurred while on an anticoagulant. Conclusion: The choice of an anticoagulant regimen after the first VTE recurrence does not impact the rate of the second recurrence.

Variability in Contemporary Heparin Prescription and Activated Clotting Time Monitoring During Percutaneous Coronary Intervention: Call for Up-To-Date Evidence-Based Guidelines

Unfractionated heparin (UFH) is the preferred anticoagulant agent in percutaneous coronary intervention (PCI) procedures for minimising the risk of thrombotic complications. Because of the narrow therapeutic range of UFH, some society guidelines have advocated the use of the activated clotting time (ACT) test to monitor anticoagulation intensity during PCI to reduce thrombotic and bleeding complications. We aimed to assess the current practice of UFH prescription and its monitoring in Australia and New Zealand (ANZ). We conducted an anonymous voluntary cross-sectional survey of interventional cardiologists (ICs) who were members of the Cardiac Society of Australia and New Zealand in 2022. The survey included 10 questions pertaining to the current practice of anticoagulation during PCI. Of 430 ICs surveyed, 148 responded (response rate, 34.4%). Most ICs (84.4%) prescribed 70-100 IU/kg of UFH for PCI. Over half of ICs (58.7%) routinely measured ACT during PCI, whereas only 22.2% routinely measured ACT after PCI to guide additional UFH prescription. Among ICs who prescribed additional UFH, approximately half (48%) aimed for ACT ≥250 seconds. Factors that influenced post-PCI UFH prescription included vascular access site and concomitant antiplatelet or anticoagulant therapy. The contemporary practice of UFH prescription during PCI and ACT monitoring in ANZ is variable and based on outdated evidence preceding current drug-eluting stents, antiplatelet therapies, and radial-first practice. Current society guideline recommendations lack clarity and agreement, reflecting the quality of the available evidence. Up-to-date clinical trials evaluating UFH prescription and ACT monitoring are needed to optimise clinical outcomes in contemporary PCI procedures.

Fibrin and Fibrinolytic Enzyme Cascade in Thrombosis: Unravelling the Role.

Blood clot formation in blood vessels (thrombosis) is a major cause of life-threatening cardiovascular diseases. These clots are formed by αA-, βB-, and ϒ-peptide chains of fibrinogen joined together by isopeptide bonds with the help of blood coagulation factor XIIIa. These clot structures are altered by various factors such as thrombin, platelets, transglutaminase, DNA, histones, and red blood cells. Various factors are used to dissolve the blood clot, such as anticoagulant agents, antiplatelets drugs, fibrinolytic enzymes, and surgical operations. Fibrinolytic enzymes are produced by microorganisms (bacteria, fungi, etc.): streptokinase of Streptococcus hemolyticus, nattokinase of Bacillus subtilis YF 38, bafibrinase of Bacillus sp. AS-S20-I, longolytin of Arthrobotrys longa, versiase of Aspergillus versicolor ZLH-1, etc. They act as a thrombolytic agent by either enhancing the production of plasminogen activators (tissue or urokinase types), which convert inactive plasminogen to active plasmin, or acting as plasmin-like proteins themselves, forming fibrin degradation products which cause normal blood flow again in blood vessels. Fibrinolytic enzymes may be classified in two groups, as serine proteases and metalloproteases, based on their catalytic properties, consisting of a catalytic triad responsible for their fibrinolytic activity having different physiochemical properties (such as molecular weight, pH, and temperature). The analysis of fibrinolysis helps to detect hyperfibrinolysis (menorrhagia, renal failure, etc.) and hypofibrinolysis (diabetes, obesity, etc.) with the help of various fibrinolytic assays such as a fibrin plate assay, fibrin microplate assay, the viscoelastic method, etc. These fibrinolytic activities serve as a key aspect in the recognition of numerous cardiovascular diseases and can be easily produced on a large scale with a short generation time by microbes and are less expensive.

Effect of an herbal medicine, Chunghyul-dan, on prevention of recurrence in patients with ischemic stroke: A retrospective cohort study.

Research indicates that Chunghyul-dan (CHD), a herbal medicine, has an inhibitory effect on stroke recurrence in small vessel disease. Recent studies have suggested that CHD might also act on large arteries. This study aimed to verify the preventive effect of CHD on strokes of all the Trial of Org 10172 in Acute Stroke Treatment (TOAST) causative classifications. We retrospectively analyzed 2 years of medical records of patients with ischemic stroke treated with CHD, 600 mg once daily, in combination with antiplatelet or anticoagulant agents. The prevalence of stroke recurrence in 2 years was analyzed. Stroke recurrence was defined as new neurological symptoms with corresponding brain imaging results. Nine of the 202 patients (4.46%) had recurrent ischemic stroke. Four occurred within 180 days, 3 between 180 and 365 days, and 2 between 365 and 730 days. All had only 1 recurrence. The recurrence rates were 1.12%, 5%, and 5.48% for small vessel occlusion, cardioembolism, and large vessel atherosclerosis, respectively. There were no adverse effects. These results suggest that CHD could inhibit ischemic stroke recurrence of all TOAST causative categories. A randomized controlled trial is needed to confirm this hypothesis.

Short versus long-term anticoagulation for left ventricular thrombosis resolution during vitamin k antagonist therapy

Abstract Background The optimal duration of anticoagulant therapy to achieve thrombus resolution and prevent cardioembolic events in left ventricular thrombosis (LVT) has not yet been established. Purpose The purpose of our study is to evaluate the incidence of LVT resolution at 3 versus 12 months of vitamin K antagonists (VKAs) therapy. Methods Consecutive patients diagnosed with LVT and treated with VKAs for at least 12 months at 5 anticoagulant outpatient clinics in Italy were retrospectively included. The primary effectiveness outcome was on-treatment thrombus resolution while the secondary was objectively documented on-treatment acute ischemic stroke, peripheral embolism, and myocardial infarction at 12-months follow-up. Safety outcomes were on-treatment major and clinically relevant non-major bleedings at 12-months follow-up as defined by the ISTH criteria. Cumulative incidences of thrombus resolution with 95% confidence intervals (CIs) were calculated while other outcomes were descriptively reported. Multivariable Cox hazards models were calculated using age, sex, reduced left ventricular ejection fraction (EF < 35%), VKAs monotherapy, and time in therapeutic range (TTR) below 60% as covariates for thrombus persistence at 12-months of follow-up. Results Out of 95 patients, 87 were finally included (Table) and 8 excluded due to the lack of relevant data. Median age was 67 years and 75.9% were men. A total of 64.4% of patients had acute myocardial infarction as risk factor for LVT development while 21.8% and 5.7% of patients had dilated and primary hypertrophic cardiomyopathy, respectively. A reduced EF and atrial fibrillation were present in 77.0% and 19.5% of patients, respectively. All but one patient received warfarin with a median TTR of 54%, and 35.5% of patients did not receive concomitant antiplatelet therapy. All included patients received VKAs for at least 12-months. The 3 and 12 month cumulative incidences (Figure) of thrombus resolution were 34.5% (95% CI, 24.7%-44.5%) and 68.3% (95% CI, 57.2%-77.1%), respectively. At multivariable Cox regression analysis, the presence of a reduced EF appeared to be associated with a higher risk of thrombus persistence at 12-months follow-up (Hazard Ratio 3.09; 95% CI 1.27-7.55; p=0.013). During 12-months follow-up, two patients (2.3%) had acute ischemic stroke at 4 and 7 months from the start of VKAs therapy. Three patients (3.4%) had a major and 5 (5.7%) a clinically relevant non-major bleeding that occurred within the first three months of VKAs. Conclusions A 12-month course of anticoagulant therapy with VKA appeared to be effective and safe in patients with LVT and appeared to be associated with a higher cumulative incidence of LVT resolution than a 3-month course. A reduced left ventricular EF was associated with a higher risk of LVT persistence. Whether anticoagulant agents with improved ease-of-use and safety profile are effective in this setting remains undefined.Baseline patients' characteristicsCumulative incidences of LVT resolution

Rivaroxaban plus aspirin vs. dual antiplatelet therapy in endovascular treatment in peripheral artery disease and analysis of medication utilization of different lesioned vascular regions.

In the management of Peripheral Arterial Disease (PAD), the administration of anticoagulant or antiplatelet agents is imperative. The use of Dual Antiplatelet Therapy (DAPT) in conjunction with rivaroxaban has shown potential in mitigating adverse outcomes. Given the heterogeneity in the pathology of lower limb arteries, there is a compelling case for individualized treatment strategies. In a single-center retrospective study on pharmacotherapy for peripheral artery disease, patients were treated with either aspirin combined with rivaroxaban or aspirin coupled with clopidogrel. The primary efficacy outcome encompassed a composite of increases in the Rutherford classification, acute limb ischemia, amputations due to vascular causes, target lesion revascularization, myocardial infarction, ischemic stroke, and cardiovascular death. The primary safety outcome was major bleeding, as defined by the Thrombolysis in Myocardial Infarction (TIMI) criteria; meanwhile, major bleeding as categorized by the International Society on Thrombosis and Haemostasis (ISTH) served as a secondary safety outcome. The study differentiated between two subgroups: patients with only above-the-knee and below-the-knee arterial lesions. From January 2016 to December 2021, 455 patients received either clopidogrel plus aspirin or rivaroxaban plus aspirin following endovascular treatment (EVT). The rivaroxaban group (n = 220) exhibited a lower incidence of primary efficacy outcomes [49.1% vs. 60.4%, hazard ratio (HR) 0.77, P = 0.006] but had more TIMI major bleeding events (5.9% vs. 2.1%, HR 2.6, P = 0.04). ISTH major bleeding events did not show a significant difference, though a higher percentage of rivaroxaban patients discontinued medication due to bleeding (10% vs. 4.7%, HR 2.2, P = 0.03). In the above-the-knee arterial disease subgroup, the rivaroxaban group demonstrated a lower incidence of primary efficacy outcomes (28.2% vs. 45.2%, HR 0.55, P = 0.02). In the below-the-knee arterial disease subgroup, no significant difference was observed in the occurrence of primary efficacy events between the two groups (58.7% vs. 64.8%, HR 0.76, P = 0.14). Rivaroxaban plus aspirin improved outcomes compared to DAPT in patients with lower extremity artery disease. Similar findings were observed in the above-the-knee artery lesion-only group. However, in the below-the-knee artery lesion-only group, rivaroxaban plus aspirin did not surpass DAPT in efficacy. Regarding safety, rivaroxaban plus aspirin exhibited higher bleeding risks and more frequent treatment discontinuation than aspirin combined with clopidogrel.

Effect of pre-procedural anticoagulation in patients undergoing ablation: a meta-analysis of randomized controlled trials

Abstract Background Atrial fibrillation (AF) is the most common type of arrhythmia seen in a clinical setting. Patients have a high risk of stroke, especially in the first two years of diagnosis. Anticoagulation therapy is prescribed to patients with a high CHAD2S2-VASc score. Based on recent evidence, catheter ablation (CA) is emerging as the preferred first-line treatment of modality. The benefit of interruption of anticoagulation before CA is unclear. Interruption of anticoagulation and insertion of a foreign body during CA can lead to an increased risk of thromboembolism (TE). Anticoagulation is interrupted before the procedure to balance the risk of TE and bleeding. Objective To assess the risk of bleeding and TE in patients undergoing CA with uninterrupted versus interrupted anticoagulation. Methods We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) strategy to search PubMed/MEDLINE, EMBASE, and Cochrane databases from inception till January 2023. We included randomized controlled trials and excluded observational studies. The data was extracted from full texts. Data Random effects model and Mantel-Haenszel method were used to calculate pooled risk ratio and 95% confidence interval. Results A total of 10 studies were included, with 4,584 participants. The risk of TE [1.76; 95% confidence interval (CI): 0.33, 9.46] and bleeding [1.10; 95% CI: 0.59, 2.05] did not change significantly with the interruption of all anticoagulation agents. Similarly, interruption of individual anticoagulants such as heparin [0.81, 95% CI: 0.19, 3.39], vitamin K antagonists (VKA) [9.21, 95% CI: 0.02, 5627.42], and direct oral anticoagulants (DOAC) [1.36, 95% CI: 0.26, 7.23] did not show any change in the risk of TE. There was no significant change in the risk of bleeding with heparin discontinuation (Figure 1). Conclusion Our study supports recent trials such as Randomized Evaluation of Long-term Anticoagulant Therapy (RE-LY) and emerging data that support uninterrupted anticoagulation prior to ablation as there is no increased risk of bleeding or TE.

Abstract 14420: Role of Thromboprophylaxis in Outpatients With COVID-19: A Meta-Analysis of Randomized Controlled Trials

Introduction: COVID-19 has been known to cause a hypercoagulable state, leading to venous and arterial thromboembolism. While thromboprophylaxis with anticoagulation (AC) agents is beneficial in hospitalized patients, their role is unclear in outpatients with COVID-19. We conducted a meta-analysis to assess the potential role of AC in outpatients with COVID-19. Methods: Multiple online databases were searched for randomized clinical trials (RCTs) comparing prophylactic AC to placebo in patients presenting in the outpatient setting with COVID-19. The primary outcomes of interest were hospitalization, death, venous thromboembolism (VTE) and bleeding at the longest available follow up. A random-effects model was used to estimate pooled risk ratios (RR) and 95% confidence intervals (CI). Results: Four RCTs with a total of 1,464 patients (AC group n=726, placebo group n=738) were included. The mean age was 55 years, 48% of patients were men and the mean duration of follow up was 65 days. Both groups had similar risk of hospitalization (RR 0.93, 95% CI 0.56-1.53, p = 0.76) (Figure 1), death (RR 1.09, 95% CI 0.07-17.14, p = 0.95), VTE (RR 0.35, 95% CI 0.08-1.49, p = 0.16) (Figure 2), and bleeding (RR 1.99, 95% CI 0.73-5.40, p = 0.18). Conclusions: Thromboprophylaxis with AC in outpatients with COVID-19 is not associated with reduction in the risk of hospitalization, death or VTE when compared with placebo.

Antimicrobial, Antidiabetic, Antioxidant, and Anticoagulant Activities of Cupressus sempervirens In Vitro and In Silico.

In the last decade, the urgent need to explore medicinal plants or drug development has increased enormously around the world to overcome numerous health problems. In the present investigation, HPLC indicated the existence of 18 phenolic and flavonoid compounds in the Cupressus sempervirens extract. Hesperetin represents the greatest concentration (25,579.57 µg/mL), while other compounds, such as pyro catechol, rutin, gallic acid, chlorogenic acid, naringenin, and quercetin, were recognized in concentrations of 2922.53 µg/mL, 1313.26 µg/mL, 1107.26 µg/mL, 389.09 µg/mL, 156.53 µg/mL, and 97.56 µg/mL, respectively. The well diffusion method documented the antibacterial/antifungal activity of C. sempervirens extract against E. faecalis, E. coli, C. albicans, S. typhi, S.aureus, and M. circinelloid with 35, 33, 32, 25, 23, and 21 mm inhibition zones, respectively, more than the standard antibiotic/antifungal agent. Low values ranging from 7.80 to 15.62 µg/mL of MIC and MBC were recorded for E. faecalis, E. coli, and C. albicans. From the 1- diphenyl-2-picryl hydrazyl (DPPH) assay, promising antioxidant activity was recorded for C. sempervirens extract with IC50 of an 8.97 µg/mL. Moreover, ferric reducing antioxidant power (FRAP) and total antioxidant capacity assays (TAC) confirmed the antioxidant activity of the extract, which was expressed as the ascorbic acid equivalent (AAE) of 366.9 ± 0.2 µg/mg and 102 ± 0.2 µg/mg of extracts, respectively. α-amylase and α-glucosidase inhibition % were determined to express the antidiabetic activity of the extract in vitro, with promising IC50 value (27.01 µg/mL) for α-amylase compared to that of acarbose (50.93 µg/mL), while IC50 value of the extract for α-glucosidase was 19.21µg/mL compared to that of acarbose 4.13 µg/mL. Prothrombin time (PT) and activated partial thromboplastin time (APTT) revealed the role of C. sempervirens extract as an anticoagulant agent if compared with the activity of heparin. Binding interactions of hesperetin and gallic acid were examined via the Molecular Operating Environment (MOE) Dock software against E. faecalis (PDB ID: 3CLQ), C. albicans (PDB ID: 7RJC), α-amylase (PDB ID: 4W93), and α-glucosidase (PDB ID: 3TOP). The obtained results shed light on how molecular modeling methods might inhibit the tested compounds, which have the potential to be useful in the treatment of target proteins.

Assessing the Feasibility of Thromboprophylaxis with Apixaban in JAK2-Positive Myeloproliferative Neoplasm Patients: The Airport-MPN Trial

Introduction: Thrombosis is a major cause of mortality and morbidity in myeloproliferative neoplasms (MPN). In patients classified as high-risk for thrombosis, current guidelines recommend the use of cytoreduction therapy and low-dose aspirin (e.g., ASA 81 mg daily) to decrease the risk of thrombotic events. However, use of low-dose aspirin is based on limited evidence and is associated with a significant failure rate. Thromboprophylaxis with low-dose direct oral anticoagulants (e.g., apixaban 2.5 mg BID) is an appealing option in MPN, specifically when patients carry the JAK2 mutation, based on the pathophysiology of thrombus formation associated with this driver mutation. In other populations, thromboprophylaxis with a low-dose direct oral anticoagulant has been associated with a reduced risk of arterial and venous thrombotic complications, when compared to low-dose aspirin. Hence, we conducted a pilot trial to assess the feasibility of conducting a randomized controlled trial evaluating the efficacy and safety of apixaban (2.5 mg BID) compared to aspirin (81 mg daily) to prevent thrombotic complications in patients with JAK2-positive MPN (JAK2MPN). Methods: This was a multi-centre, prospective, open-label, blinded endpoint pilot trial (NCT04243122), conducted in three Canadian centers (Ottawa, Calgary, Sherbrooke). Adult patients with a confirmed diagnosis of polycythemia vera, JAK2-positive essential thrombocythemia or JAK2-positive pre-fibrotic myelofibrosis (per local clinical definitions) requiring low-dose aspirin for thromboprophylaxis were eligible. Both patients with an incident diagnosis of JAK2MPN (defined as diagnosed within 1 year) and patients with prevalent disease were targeted for recruitment. Exclusion criteria included a contraindication to thromboprophylaxis or the need for a specific anticoagulant or non-aspirin anti-platelet agent. Patients with a prior history of venous thromboembolism were eligible if they had completed a minimum of 6 months of anticoagulation therapy. Participants were randomized 1:1 to receive apixaban 2.5mg BID or aspirin 81mg daily, along with cytoreductive therapy (per guidelines). The study treatment duration was 6 months. Follow-up occurred at 3, 6 and 7 months after allocation of the study medication. The primary study outcome for feasibility was the monthly recruitment rate per study site over a 6-month follow-up period. Secondary outcomes included rates of thrombotic and bleeding complications. The total estimated sample size was 44 participants (22 per arm). Due to the COVID-19 pandemic, not all sites were able to start recruitment at the same time and the total recruitment period spanned over 24 months. Results: During this 24-month recruitment period, 93 JAK2MPN patients were screened for eligibility. Of these, 69 were eligible and 64% of eligible patients consented to participate. We therefore recruited 44 participants, for a recruitment rate of 0.8 patient per centre per month. Baseline characteristics of participants are presented in Table 1. A total of 29 prevalent cases and 15 incident cases were included. Secondary efficacy, safety, and feasibility outcomes (relating to thrombotic events, bleeding complications, and study compliance) will be available at the ASH Meeting, since all participants will have completed the 6-month treatment duration by October 2023. Discussion: Despite the challenges of the COVID-19 pandemic, we have recruited 100% of our target population. Given the chronicity of MPN, most outpatient clinics functioned remotely during the pandemic, precluding recruitment. Nevertheless, by adapting to the realities of the pandemic, we achieved our recruitment target demonstrating feasibility of a larger trial. The strategies adopted during this pilot trial to recruit participants, such as active screening of clinic lists for potential participants and direct communication with MPN specialists, will be applied to our larger scale trial. Conclusion: This pilot trial demonstrated the feasibility of conducting a large-scale trial evaluating the superiority of apixaban over aspirin for the thromboprophylaxis of JAK2MPN patients. As JAK2MPN are rare diseases, we have partnered with counterparts in France to conduct an international study on the efficacy and safety of direct oral anticoagulant thromboprophylaxis in JAK2MPN patients.

Impact of Anticoagulation in Acquired Hemophilia a

Background Acquired Hemophilia A (AHA) is a rare autoimmune disorder that occurs due to the development of autoantibodies against factor VIII which leads to inhibition of the coagulation cascade and results in a propensity for hemorrhage. The estimated incidence is approximately 1.5 per million per year. It carries an exceptionally high morbidity and mortality rate, with severe or life-threatening hemorrhagic events occurring in 70-90% of cases, with 5-10% of these cases resulting in mortality. Several underlying conditions are associated with AHA, including autoimmune disorders, obstetrical and oncologic disease, and various medications, such as direct oral anticoagulants (DOACs) and antiplatelet therapy (APT), both of whose usage has increased significantly over the past decade. Objectives We aimed to evaluate whether patients prescribed an antiplatelet or anticoagulant at the time of diagnosis of AHA experienced more severe bleeding and worse clinical outcomes compared to those with AHA not prescribed an antiplatelet or anticoagulant. Methods This is a single-center retrospective study examining 16 individuals with AHA from April 2013 to April 2023. These individuals were categorized by the presence or absence of a prescribed anticoagulant and then further divided into class of anticoagulant (APT, DOAC or other oral anticoagulant (OAC), or exposure to both). Primary end points included the number of blood product transfusions received, hospital length of stay (LOS), need for intervention or procedure, and degree of hemoglobin (Hgb) drop from baseline. Continuous variables were compared using t-test or Wilcoxon rank-sum test while categorical variables were compared using the chi-square test or Fisher's exact test. Results Of the 16 individuals in our cohort, 9 were without prior exposure to anticoagulation or antiplatelet agents before the diagnosis of AHA while 7 were prescribed either an anticoagulant, antiplatelet agent, or both. Of those taking one of these classes of medications, 2 were prescribed OACs, 3 were prescribed APTs, and 2 were prescribed both classes. The mean baseline Hgb was similar in both groups, 12.84 for the non-exposed group and 12.92 for the exposed group, while mean Hgb at diagnosis was 9.55 and 8.81 for the non-exposed group and exposed group respectively (p-value 0.638). Median factor VIII titer inhibitors at diagnosis were 3.30 and 38.10 (p-value 0.124) for non-exposed and exposed groups, respectively. Mean hospitalization rates for non-exposed individuals versus exposed individuals were 5.0 and 7.0 (p-value 2.00) with a mean hospital LOS of 10.20 and 12.57 days (p-value 0.624) in the non-exposed and exposed group, respectively. The mean number of packed red blood cell (pRBC) transfusions needed during the index hospitalization was 1.6 and 3.0 (p-value 0.333) in the non-exposed group and exposed group respectively while the mean number of platelet transfusions were 4 and 6 in the non-exposed and exposed groups respectively. There was a statistically significant increase in intramuscular bleeding with a mean of 1.0 and 5.0 (p-value 0.035) in the non-exposed and exposed groups respectively. In each group there was only one individual who required procedural intervention. There was one death due to hemorrhage which occurred in the exposed group (p-value 0.467). Conclusions The increased rates of intramuscular bleeding in patients exposed to prior anticoagulation was statistically significant. Intramuscular hemorrhage is associated with increased morbidity due to the risk for compartment syndrome requiring surgical intervention. Our data demonstrates a trend towards the need for a longer hospitalization and more pRBC transfusions in individuals with prior exposure though notably, there is not an apparent increased trend for an increased rate of platelet transfusions. There is also a trend towards significance for higher factor VIII titer inhibitor levels in patients on anticoagulation at the time of diagnosis. While this study is limited in power by the sample size, there are no comparable studies to date examining the impact of anticoagulation on individuals with AHA. With the increasing rates of anticoagulation therapy, further investigation is needed on the impact of therapeutic anticoagulant or antiplatelet use prior to the diagnosis of AHA and subsequent clinical outcomes.

Leukemia Inhibitory Factor, Tissue Factor, Thrombomodulin, P-Selectine, D-Dimer, Thrombin Generation and Procoagulant Phospholipid Dependent Clotting Time Are Predictive for in Vitro Fertilization Outcome. the Prospective Roadmap-IVF Study

Background The link between blood hypercoagulability, endothelial cell activation and infertility or in vitro fertilization (IVF) failure is a puzzling issue. Activation of platelets, endothelial cells and blood coagulation, proinflammatory and angiogenetic potential play important role in implantation and early embryonic development. Biomarkers of cellular hypercoagulability are associated with high risk of IVF failure. Soluble Leukemia Inhibitory Factor (LIF), an interleukin 6 class cytokine expressed in the trophectoderm of the developing embryo is an important regulator in the establishment of pregnancy. Endoglin (Eng), a co-receptor for TGF-β1 and TGF-β3 is implicated in vascular complications of pregnancy and particularly in preeclampsia. Aim: The prospective longitudinal monocentric observational cohort study ROADMAP-IVF, evaluated the synergistic prognostic value of LIF and Eng with the biomarkers of cellular hypercoagulability in predicting the endometrial receptivity of fresh IVF cycles. Materials and Methods. The ROADMAP-IVF enrolled 40 women eligible for IVF with normal blood count, PT, aPTT, Fg, renal and liver function. The control group (CG) consisted of 30 healthy women with history of uncomplicated pregnancies. Exclusion criteria: Use of anticoagulant or antiplatelet agents during the last 30 days before inclusion. Known cardiovascular disease, active cancer. Active corticosteroid treatment. Primary end-point: Echographically documented pregnancy at 7 weeks from implantation. Blood was collected on day 2 (D2) from the natural cycle and 6 days after hormone treatment initiation corresponding to D8 of the cycle. Procoagulant phospholipid-dependent clotting time (PPL-ct), tissue factor (TF), thrombomodulin (TM), von Willebrand factor (vWF) and D-Dimers (DDi) were measured with assays from Diagnostica Stago (Asnieres, France). P- and E-Selectin, LIF and Eng were measured with ELISA. Thrombin generation (TG) with the TF 5 pM PPP-Reagent ® was assessed on Calibrated Automated Thrombogram (Stago, France). The cut-off values for studied biomarkers have been selected on the basis of ROC analysis. Univariate and multivariate logistic regression analysis examined the associations between the biomarkers and the study outcome. Results: 40 women were enrolled in the study. In 11 women pregnancy was confirmed with ultrasound and in 23 women no pregnancy was echographically documented. Age was not significantly different between the IVF (41 ys; range 22 - 48 ys) and the control group (40 ys; range 20 - 46 ys). At D2 and D8 the DDi and LIF were significantly higher in IVFG as compared to the CG. At D2 most of the patients had PPL-ct, DDi and MRI of TG higher than the upper normal limit (UNL). At D8 only TF was significantly increased as compared to the CG. Analytical data are presented in Table 1. Age did not correlate with the levels of the studied biomarkers. Significant correlations (p<0.05) were found between DDi and ETP (r=0.35); TM, TF and P-Selectin (r=0.4) at D2; TF, LIF and Eng (r=0.5) at D2 and D8; P-Selectin and PPL-ct (r=-0.4) at D2; P-Selectin and TM (r=0.4), E-Selectin (r=0.5), LIF (0.4) at D2; E-Selectin and P-Selectin (r=0.5), TF (r=0.3), and LIF (r=0.4) at D2. The ROC analysis showed that IVF failure was associate with DDi increase at D2 (AUC = 0.64); P-Selectin increase at D2(AUC = 0.57) and D8 (AUC = 0.61); TM increase at D8 (AUC = 0.61); TF increase at D8 (AUC = 0.57); LIF increase at D8 (AUC = 0.59); ETP increase at D2 (AUC = 0.67) and D8 (AUC = 0.67); Peak increase at D2 (AUC = 0.64) and D8 (AUC = 0.61). Prolongation of PPL-ct on D8 was predictive for positive pregnancy outcome(AUC 0.64). Conclusion The ROADMAP-IVF study showed that at least one out of four women eligible for IVF present biological evidence of activation of platelets, endothelial cells, blood coagulation or LIF upregulation. Hormone treatment administration does not significantly alter the proinflammatory or the hypercoagulable state. Among the studied biomarkers the levels of LIF, DDi, P-Selectine, TM and TF as well as the status of thrombin generation and PPL-ct showed a significant predictive value for the IVF outcome, particularly when measured at 6 days after hormone treatment administration. These findings will lead to the elaboration of an risk assessment model for IVF failure combining the selected biomarkers of hypercoagulability with LIF.

Comparative effectiveness of two intravenous immunoglobulin products in children with Kawasaki disease, a nationwide cohort study

Kawasaki Disease (KD) is the most common acquired pediatric heart disease in the developed world. Rapid infusion of high-dose intravenous immunoglobulin is the standard therapy. Different manufacturing processes of IVIG may influence their efficacy. This study aims to conduct a head to head comparison of two IVIGs, TBSF and Privigen, from a nationwide perspective. The main data source was the National Health Insurance Research Database (NHIRD) of Taiwan. A total of 3368 KD cases involving children under 2 years of age were enrolled from January 2015 to November 2020. The primary endpoint was IVIG resistance, which we defined as the total amount exceeding 26 g in one admission. The secondary endpoints encompassed two distinct criteria: coronary involvement, which was defined as the prolonged use of aspirin or anti-coagulation agents between 180 and 360 days after the index date, and recurrence, which was defined as readmission for IVIG therapy occurring more than 30 days after previous KD index day and continuing until the end of the follow-up period. Privigen demonstrated a lower IVIG resistance rate at 9.4% in comparison to TBSF, which exhibited a rate of 9.7% (odds ratio 0.72, 95% CI 0.52–0.99). Privigen had a lower odds of coronary involvement (odds ratio 0.38, 95% CI 0.18–0.82). There is no difference in recurrence rate (odds ratio 0.60, 95% CI 0.22–1.68). Privigen might have a lower rate of IVIG resistance and reduced coronary artery involvement. The discrepancy may be due to the concentration, the stabilizers, or the source of plasma. Further investigation is needed to compare the effectiveness of different IVIGs in the large randomized controlled clinical trial.

Surface Engineering of Bioactive Coatings for Improved Stent Hemocompatibility: A Comprehensive Review.

Cardiovascular diseases continue to be a major contributor to illness and death on a global scale, and the implementation of stents has given rise to a revolutionary transformation in the field of interventional cardiology. The thrombotic and restenosis complications associated with stent implantation pose ongoing challenges. In recent years, bioactive coatings have emerged as a promising strategy to enhance stent hemocompatibility and reduce thrombogenicity. This review article provides an overview of the surface engineering techniques employed to improve the hemocompatibility of stents and reduce thrombus formation. It explores the mechanisms underlying thrombosis and discusses the factors influencing platelet activation and fibrin formation on stent surfaces. Various bioactive coatings, including anticoagulant agents, antiplatelet agents, and surface modifications, are discussed in detail, highlighting their potential in reducing thrombogenicity. This article also highlights a multitude of surface modification techniques which can be harnessed to enhance stent hemocompatibility including plasma treatment, physical vapor deposition (PVD), chemical vapor deposition (CVD), and electrodeposition. These techniques offer precise control over surface properties such as roughness, charge, and composition. The ultimate goal is to reduce platelet adhesion, tailor wettability, or facilitate the controlled release of bioactive agents. Evaluation methods for assessing hemocompatibility and thrombogenicity are also reviewed, ranging from in vitro assays to animal models. Recent advances in the field, such as nanotechnology-based coatings and bioactive coatings with controlled drug release systems, are highlighted. Surface engineering of bioactive coatings holds great promise for enhancing the long-term outcomes of stent implantation by enhancing hemocompatibility and reducing thrombogenicity. Future research directions and potential clinical applications are discussed, underscoring the need for continued advancements in this field.

Comparison of direct oral anticoagulants versus low-molecular-weight heparin in primary and metastatic brain cancers: a meta-analysis and systematic review

BackgroundThe safety and efficacy of direct-acting oral anticoagulants (DOACs) for therapeutic anticoagulation in the setting of primary or metastatic brain cancer is not known. ObjectivesTo conduct a meta-analysis and systematic review of studies that compare the risk of intracranial hemorrhage (ICH) in patients with brain cancer treated with DOACs vs low-molecular-weight heparin (LMWH). MethodsA literature search was conducted using PubMed, EMBASE, and Cochrane databases. Summary statistics were obtained by calculating the risk ratio (RR), and heterogeneity across studies was estimated using the I2 statistic. A total of 10 retrospective studies (n = 1638) met criteria for inclusion. The primary endpoint was the pooled RR for ICH in patients with brain tumors receiving anticoagulation with DOACs compared with those receiving LMWH. Secondary analyses included the risk of fatal ICH in each subgroup. ResultsThe pooled RR for ICH in patients receiving DOACs vs those receiving LMWH was 0.65 (95% CI, 0.36-1.17; P = .15; I2 = 50%). In studies evaluating primary brain cancer, there was a reduction in risk of ICH with DOACs (RR, 0.35; 95% CI, 0.18-0.69; P = .003; I2 = 0%). In patients with metastatic brain cancer, there was no difference in the risk of ICH with the type of anticoagulation (RR, 1.05; 95% CI, 0.71-1.56; P = .80; I2 = 0%). The overall risk of fatal ICH was not different between anticoagulants. ConclusionThe risk of ICH in patients with brain cancer receiving therapeutic anticoagulation varies by anticoagulation agent and diagnosis of primary or metastatic disease.

Abelacimab in Cancer-Associated Thrombosis: The Right Drug at the Right Time for the Right Purpose. A Comprehensive Review.

Cancer-associated thrombosis (CAT) is a devastating complication of cancer that can significantly impact a patient's health and life. The incidence of CAT is approximately 20%, and 1 in 5 cancer patients will develop CAT annually. Indeed, CAT can promote pulmonary embolism and deep vein thrombosis, leading to increased morbidity and mortality that dramatically impact survival. CAT can also provoke delay or discontinuation of anticancer treatment, which may result in a lack of treatment efficacy and high costs for patients, institutions, and society. Current guidelines advocate direct oral anticoagulants (DOACs) as the first-line anticoagulant option in CAT. Compared to low-molecular-weight-heparins (LMWHs), DOACs are advantageous in that they typically have an oral route of administration, do not require laboratory monitoring, and have a more predictable anticoagulant effect. However, in patients with thrombocytopenia, renal failure, or those receiving anticancer regimens with potential for drug-drug interactions, LMWH is still the mainstay of care. The main limitation of current anticoagulant agents is related to bleeding risk (BR), both for DOACs and LMWHs. Specifically, DOACs have been associated with high BR in gastrointestinal and genitourinary cancers. In this challenging scenario, abelacimab, an anti-factor XI agent, could represent a viable option in the management of CAT due to its "hemostasis sparing" effect. The safe profile of abelacimab could be useful in patients with active malignancy and CAT, as long-term anticoagulant therapy is often required. Two ongoing international phase III trials (Aster and Magnolia) compare abelacimab with the standard of care (i.e., apixaban in patients with CAT and dalteparin in those with CAT and high BR, respectively). Abelacimab is a new and attractive anticoagulant for the management of CAT, especially in the insidious and critical scenario of active cancer patients with venous thromboembolism and high BR. The aim of this narrative review is to discuss the updated evidence on the performance of DOACs and LMWHs in the treatment of CAT and to focus on the potential role of abelacimab in CAT and its promising associated clinical trials.

Molecular Docking and Dynamics Simulations of Ammi visnaga L. Constituents as Antimelanogenic, Anti-Inflammatory and Anticoagulant Agents.

In this study, anti-melanogenic, anti-inflammatory and anti-coagulant potentials of eighteen selected constituents of Ammi visnaga L. were investigated by Induced Fit Docking (IFD) and molecular dynamic simulation with Schrödinger software. The binding free energies of the selected natural compounds were computed by means of ΔG MM-GBSA studies. Anti-melanogetic activity of the constituent against agaricus bisporus tyrosinase, Priestia megaterium tyrosinase and Homo sapiens tyrosinase were evaluated. The result showed that apiumetin had more negative binding free energy against three tyrosinase enzymes than cognate ligands, tropolone and kojic acid. Docking analysis was also performed to predict the constituents with anti-inflammatory activity against human Tumor necrosis factor, Cyclooxygenase-2, Prostaglandin D2 11-ketoreductase AKR1C3 and Prostaglandin reductase PTGR2. The results showed that pyranocoumarins (visnadin, dihydrosamidin, samidin) have more negative binding free energy against Cyclooxygenase-2 and Prostaglandin D2 11-ketoreductase receptors than cognate drugs, rofecoxib and indomethacin. In addition, docking analysis shows that pyranocoumarins, apiumetin and cimifugin have more negative binding free energy against Vitamin K epoxide reductase than S-warfarin drug, predicting that they have anticoagulant activity. Furthermore, the constituents and their cognate drugs were subjected to 100 ns MD Simulation to predict their stability at the active sites of the enzymes.