Oral anticoagulant therapy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

Direct oral anticoagulant prescribing trends for venous thromboembolism among adult patients with obesity at University of Utah Health

BACKGROUND

Anticoagulants, including warfarin and direct oral anticoagulants (DOACs), are used to prevent and treat venous thromboembolism (VTE) which is common in patients with obesity. Guidance statements regarding use of DOACs for VTE treatment in this patient population have been updated.

OBJECTIVE

Examine DOAC prescribing trends in patients with obesity and VTE.

METHODS

We performed a retrospective, single-site cross-sequential study of DOAC prescribing trends in adult patients with obesity (BMI ≥30) and objectively confirmed VTE diagnosis between 2014 and 2022. The primary outcome of interest was the proportion of patients with obesity prescribed DOACs.

RESULTS

A total of 1826 patients were included in our analysis. Most patients were of White race (85.8 %) and approximately half were female. Pulmonary embolism was the most common VTE type (62.2 %). A total of 1018 patients were prescribed DOAC therapy (55.8 %), 524 warfarin therapy (28.7 %), and 284 enoxaparin (15.6 %). Logistic regression analysis revealed that the utilization of DOACs exhibited a significant upward trend from 2017 to 2022 (odds ratio [OR] 1.85 to 14.08 compared to 2014), but not from 2015 to 2016 (OR 1.30 to 1.52). Patients with BMI ≥ 40 and ≥ 50 were twice and 4-times as likely to be prescribed warfarin than DOACs, respectively.

CONCLUSION

Between 2017 and 2022, the proportion of patients with obesity prescribed DOACs for the treatment of VTE increased significantly. This suggests an increasing likelihood to prescribe DOACs in this patient population despite the lack of safety and efficacy data from randomized controlled trials except for very heavy patients.

Accuracy of an internationally validated genetic-guided warfarin dosing algorithm compared to a clinical algorithm in an Arab population

PURPOSE

To identify the impact of CYP2C9*2, *3, VKORC1-1639 G>A and CYP4F2*3 on warfarin dose in an Arab population. To compare the accuracy of a clinical warfarin dosing (CWD) versus genetic warfarin dosing algorithms (GWD) during warfarin initiation.

METHODS

A cohort of Arab patients newly starting on warfarin had their dose calculated using CWD published in www.warfarindosing.org and were followed for 1 month. Each patient provided a saliva sample. DNA was extracted, purified and genotyped for VKORC-1639 G>A, CYP2C9*2, CYP2C9*3 and CYP4F2*3. After reaching warfarin maintenance dose, the dose was recalculated using the GWD and median absolute error (MAE) and the percentage of warfarin doses within 20% of the actual dose were calculated and compared for the two algorithms.

RESULTS

The study enrolled 130 patients from 12 Arabian countries. Compared to those with wild type, carriers of reduced function alleles in CYP2C9 required significantly lower median (IQR) warfarin weekly dose [24.5 (15.3) vs. 35 (29.8) mg/week, p=0.006]. With regards to VKORC, patients with AA genotype had a significantly lower median (IQR) weekly warfarin dose compared to AG and GG [21(10.5) vs 29.4 (21), p<0.001 for AA vs AG, p<0.001 for AA vs GG]. The MAE (IQR) for the weekly dose of the GWD was significantly lower compared to CWD [8.1 (10.5) vs 12.4 (12.6) (p<0.001)].

CONCLUSION

CYP2C9 and VKORC1 variants are important determinants of warfarin dose in the Arab population. The use of the genetic and clinical factors led to better warfarin dose estimation when compared to clinical factors alone.

Changes in the landscape of anticoagulation: a focus on direct oral anticoagulants

Over the last decade, the advent of direct oral anticoagulants (DOACs) has rapidly changed the landscape of anticoagulation. In the early 2010s, DOACs became widely available for stroke prevention in atrial fibrillation and the treatment of venous thromboembolism. About 10 years later, approximately two-thirds of patients requiring oral anticoagulant treatment were receiving a DOAC. The results of several post-marketing studies consistently confirmed the findings of phase 3 clinical trials, and research has focused on new areas of development, with heterogeneous results. A role for DOACs has emerged for patients with peripheral artery disease and other challenging conditions, such as cancer-associated thrombosis, unusual-site venous thromboembolism, and end-stage renal disease. Conversely, clinical trials showed that DOACs were not efficacious in patients with valvular atrial fibrillation, mechanical heart valves, embolic strokes of undetermined source, or antiphospholipid syndrome. In this Review, we discuss the impact of DOACs in clinical practice over the last decade, new areas under development, and practical issues in the management of these drugs.

Discovery of a new lead molecule to develop a novel class of human factor XIIa inhibitors

Factor XIIa (FXIIa) is a plasma serine protease within the contact activation pathway. Inhibiting FXIIa could offer a viable therapeutic approach for achieving effective and safer anticoagulation without the bleeding risks that accompany the use of existing anticoagulants. Therefore, we investigated the anticoagulant properties of an amidine-containing molecule (inhibitor 1) to identify a potential lead molecule for subsequent development of FXIIa inhibitors. Results indicated that inhibitor 1 primarily inhibits human FXIIa with an IC50 value of ~30 µM. The inhibitor demonstrated variable selectivity against thrombin, factor IXa, factor Xa, factor XIa, and activated protein C. Michaelis-Menten kinetics indicated that the molecule is an active site inhibitor of FXIIa. Molecular modeling studies revealed that the molecule recognizes residues His57, Asp189, and Ala190 in FXIIa's active site. The inhibitor selectively and concentration-dependently prolonged the clotting time of human plasma under activated partial thromboplastin time assay conditions. The inhibitor did not exhibit significant cytotoxicity in human HEK293 cells and the in silico pharmacokinetics and toxicology data were comparable to known anticoagulants. This study introduces inhibitor 1 as a lead platform for further development as an anticoagulant to provide a more effective and safer approach to preventing and treating thromboembolic diseases.

Structure-based design and synthesis of novel FXIa inhibitors targeting the S2' subsite for enhanced antithrombotic efficacy

Factor XIa (FXIa), a key component of the intrinsic coagulation pathway, has recently been recognized as a safe and effective target for antithrombotic therapy. Research indicates that FXIa inhibitors can lower bleeding risk compared to novel oral anticoagulants. In this study, we designed and synthesized a series of novel FXIa inhibitors based on the structure of Asundexian, with a particular focus on optimizing the P2' region to enhance binding to the S2' subsite of FXIa. This strategy led to the discovery of compound F47, which demonstrated significantly greater FXIa inhibition (IC50 = 2.0 nM) compared to Asundexian (IC50 = 5.0 nM). F47 also showed excellent anticoagulant activity in the aPTT assay (EC2x = 0.4 μM), with strong efficacy and minimal impact on the extrinsic coagulation pathway. Additionally, F47 exhibited inhibitory activity against plasma kallikrein (PKal), with selectivity comparable to that of Asundexian. The compound also displayed acceptable stability in human liver microsomal stability assays. Molecular modeling revealed that F47 binds tightly to the S1, S1', and S2' pockets of FXIa while maintaining key interactions; notably, its P2' moiety forms two additional π-π stacking interactions with the crucial amino acid TYR143. Further studies demonstrated that F47 exhibits dose-dependent antithrombotic efficacy in a rat FeCl3-induced thrombosis model. Ongoing research aims to further elucidate the potential of compound F47 as a promising lead in antithrombotic therapy.

Transitioning between therapeutic anticoagulants: a clinicians guide to switching patients to or from DOAC therapy

INTRODUCTION

The transition to or from direct oral anticoagulants (DOACs) is common in clinical practice.

AREAS COVERED

A literature search was conducted on PubMed, Google Scholar, and UpToDate up to March 2024 for conditions and approaches for transitioning from one agent to the other. No randomized clinical trials were retrieved except for two studies regarding switching to DOAC in well-conducted vitamin K antagonist (VKA) therapy. A narrative review was conducted addressing the conditions for switching from one agent to the other, such as thromboembolic events and major bleeding during anticoagulation, development or worsening of kidney or liver failure, initiation of interfering drugs, adverse events such as allergic reactions, frailty, patients' preferences, and affordability. During transitions from one anticoagulant to the other, the risk of both thromboembolic and bleeding complications should be minimized. The current approaches for such transitions are derived from those employed in clinical trials evaluating DOAC and from product information.

EXPERT OPINION

Many uncertainties remain regarding those circumstances requiring a change in anticoagulant strategies, as they lack evidence-based guidance. It can be envisaged that the problem of switching to and from DOAC will need additional studies especially addressing the conditions and the best approach to such transitions.

Bleeding Complications of Anticoagulation Therapy in Clinical Practice-Epidemiology and Management: Review of the Literature

Due to their very wide range of indications, anticoagulants are one of the most commonly used drug groups. Although these drugs are characterized by different mechanisms of action, the most common complication of their use is still bleeding episodes, the frequency of which depends largely on the clinical condition of the patient using such therapy. For this reason, to this day, the best method of preventing bleeding complications remains the assessment of bleeding risk using scales such as HAS-BLED. There are many reports in the literature assessing the occurrence of this type of complication after the use of drugs affecting the coagulation process, as well as many reports comparing individual groups of drugs with different mechanisms of action. However, there are still no clear guidelines that would indicate which group of anticoagulants should be preferred in particular groups of patients. The aim of our article is to summarize the data collected so far regarding the safety of using specific groups of anticoagulants and the frequency of bleeding complications after their use.

A comparative study of the clinical benefits of rivaroxaban and dabigatran in patients with nonvalvular atrial fibrillation with high bleeding risk

Objective

Rivaroxaban and dabigatran are approved to reduce the risk of stroke in patients with nonvalvular atrial fibrillation (NVAF). However, the clinical benefits of rivaroxaban and dabigatran in people with high bleeding risk are unclear.

Methods

A retrospective study was conducted on NVAF patients admitted to the First Affiliated Hospital of Zhengzhou University from May 31, 2016 to May 31, 2019. These patients had a high risk of bleeding and were taking at least one study medication. The aim of the study was to evaluate clinical benefits by comparing the efficacy and safety risks of these two medications.

Results

A total of 1,301 patients with high bleeding risk were enrolled, including 787 patients in the rivaroxaban group and 514 patients in the dabigatran group. Results of the primary efficacy benefit endpoint were obtained from 104 patients (13.21%) in the rivaroxaban group and 81 (15.76%) patients in the dabigatran group [hazard ratio (HR): 0.860; 95% confidence interval (CI): 0.637-1.162; P = 0.327], this indicates that there was no significant difference between dabigatran and rivaroxaban in preventing stroke and systemic embolism in patients with high bleeding risk NVAF. The principal safety end points were observed in 49 (6.23%) patients in the rivaroxaban group and in 36 (7.00%) patients in the dabigatran group (HR: 0.801 in the rivaroxaban group; 95% CI: 0.512-1.255; P = 0.333), this indicates that there was no a significant difference in reducing fatal bleeding and critical organ bleeding. With respect to secondary efficacy and benefit endpoints, 28 (3.56%) patients in the rivaroxaban group and 26 (5.06%) patients in the dabigatran group died, with an HR of 0.725 (95% CI: 0.425-1.238; P = 0.239); 32 (4.07%) patients in the rivaroxaban group; and 31 (6.03%) patients in the dabigatran group had myocardial infarction (MI), with an HR of 0.668 (95% CI: 0.405-1.102, P = 0.114) in the rivaroxaban group, this indicates that there was no significant difference between dabigatran and rivaroxaban in preventing all-cause death and MI.

Conclusions

In NVAF patients with high bleeding risk, there was no significant difference between dabigatran and rivaroxaban in preventing stroke and systemic embolism. There was also no significant difference between dabigatran and rivaroxaban in reducing fatal and critical organ bleeding.

Clinical Trial Registration

Chinese Clinical Trials Registry, identifier ChiCTR2100052454.

Timing Matters: A Machine Learning Method for the Prioritization of Drug-Drug Interactions Through Signal Detection in the FDA Adverse Event Reporting System and Their Relationship with Time of Co-exposure

INTRODUCTION

Current drug-drug interaction (DDI) detection methods often miss the aspect of temporal plausibility, leading to false-positive disproportionality signals in spontaneous reporting system (SRS) databases.

OBJECTIVE

This study aims to develop a method for detecting and prioritizing temporally plausible disproportionality signals of DDIs in SRS databases by incorporating co-exposure time in disproportionality analysis.

METHODS

The method was tested in the Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). The CRESCENDDI dataset of positive controls served as the primary source of true-positive DDIs. Disproportionality analysis was performed considering the time of co-exposure. Temporal plausibility was assessed using the flex point of cumulative reporting of disproportionality signals. Potential confounders were identified using a machine learning method (i.e. Lasso regression).

RESULTS

Disproportionality analysis was conducted on 122 triplets with more than three cases, resulting in the prioritization of 61 disproportionality signals (50.0%) involving 13 adverse events, with 61.5% of these included in the European Medicine Agency's (EMA's) Important Medical Event (IME) list. A total of 27 signals (44.3%) had at least ten cases reporting the triplet of interest, and most of them (n = 19; 70.4%) were temporally plausible. The retrieved confounders were mainly other concomitant drugs.

CONCLUSIONS

Our method was able to prioritize disproportionality signals with temporal plausibility. This finding suggests a potential for our method in pinpointing signals that are more likely to be furtherly validated.

Safety and Effectiveness of Four-Factor Prothrombin Complex Concentrate in Special Populations with INR Below 2: A Post-Marketing Surveillance Study

INTRODUCTION

We previously conducted a prospective, observational post-marketing surveillance study to assess the safety and effectiveness of four-factor prothrombin complex concentrate (4F-PCC) for rapid vitamin K antagonist (VKA) reversal in Japanese patients.

METHODS

This subgroup analysis compared the safety, especially thromboembolic events (TEEs), and effectiveness of 4F-PCC by stratifying patients into two subgroups according to baseline international normalized ratio (INR) levels with < 2.0 and ≥ 2.0.

RESULTS

Of 1271 eligible patients, 215 (17.9%) had INR < 2.0 and 987 (82.1%) had INR ≥ 2.0. Overall baseline characteristics were similar between groups; age (74.0 years vs 74.0 years), body mass index (22.1 kg/m2 vs 21.9 kg/m2), ratio of inpatients (90.2% vs 88.7%), manifested atrial fibrillation (46.0% vs 48.8%). Median INRs at baseline were 1.72 (minimum 0.92, maximum 1.99) in the INR < 2.0 group and 2.95 (2.00, 27.11) in the INR ≥ 2.0 group. The most common reason for 4F-PCC administration was intracranial hemorrhage (67.0% vs 59.5%), and lesser gastrointestinal bleeding (0.9% vs 7.5%). After 4F-PCC administration (average doses 24.5 IU/kg [INR < 2.0 group] and 29.2 IU/kg [INR ≥ 2.0 group]), INRs were significantly reduced to 1.21 (- 28%) and 1.31 (- 68%), respectively, and resulted in hemostasis in a similarly rapid manner. The incidences of adverse drug reactions were 3.7% in each group. TEEs occurred in 4 (1.9%) patients in the INR < 2.0 group and 11 (1.1%) patients in the INR ≥ 2.0 group and were predominantly composed of stroke, while similar rates (67.0% vs 62.9%) of bleeding events post-anticoagulant resumption were observed between groups.

CONCLUSION

This study supports the favorable tolerability and efficacy of 4F-PCC regardless of baseline INR (< 2.0 or ≥ 2.0), with a prompt reduction of INR and substantial hemostatic effectiveness in the real-world setting for patients requiring urgent VKA reversal, although no indicated 4F-PCC dose for VKA reversal exists for INR < 2.0 to date.

The pharmacokinetics of dabigatran in a rat model of hyperlipidaemia induced by poloxamer 407

Various pharmacokinetic changes have been reported in experimental hyperlipidemic (HL) animal models. To evaluate whether P-glycoprotein (P-gp) activity was affected in HL rats, we assessed the pharmacokinetics of dabigatran after oral administration of dabigatran etexilate (DABE); this is a dabigatran prodrug and a well-known P-gp substrate.HL and control rats exhibited similar area under the plasma concentration-time curve (AUC), total body clearance (CL), and steady state volume of distribution (Vss) values following intravenous administration of dabigatran (1 mg/kg). This suggested that the distribution and elimination of dabigatran were similar in control and HL rats.The hepatic and intestinal P-gp protein levels did not differ significantly between control and HL rats. The dabigatran AUC and extent of absolute oral bioavailability (F) values were similar in control and HL rats following oral administration of DABE (10 mg/kg as dabigatran). Therefore, there was no apparent change in intestinal P-gp activity in HL rats compared to control rats.This study revealed no significant change in P-gp expression or activity in the intestine or liver of HL rats, and similar pharmacokinetics of dabigatran. Hyperlipidaemia may not directly affect the oral absorption of P-gp substrate drugs.

Comparative effectiveness of warfarin management strategies: a systematic review and network meta-analysis

Background

The management of warfarin therapy presents clinical challenges due to its narrow therapeutic index. We aimed to evaluate the comparative effectiveness of different management strategies in patients using warfarin.

Methods

PubMed, Embase, Cochrane CENTRAL, CINAHL, and EBSCO Open Dissertation were searched from inception to 8 May 2024. Randomized controlled trials that compared the following interventions: patient self-management (PSM), patient self-testing (PST), anticoagulation management services (AMS), and usual care in patients prescribed warfarin for any indication were included. Risk ratios (RR) with 95% confidence interval (CI) were estimated using a random-effects model. Surface under the cumulative ranking curves (SUCRA) were used to rank different interventions. The certainty of evidence was assessed using the Confidence in Network Meta-Analysis (CINeMA) online platform. This study is registered with PROSPERO (CRD42023491978).

Findings

Twenty-eight trials involving 8100 participants were included, with follow-up periods of 1-24 months. Mean warfarin dosages were 4.9-7.2 mg/day. Only PSM showed a significant reduction of major TE risk compared with usual care (RR = 0.41; 95% CI: 0.24, 0.71; I2 = 0.0%) with moderate certainty of evidence. The 97.6% SUCRA also supported the beneficial effects of PSM over other interventions. The combined direct and indirect evidence showed significantly higher TTR in PSM compared with usual care (MD = 7.39; 95% CI: 2.39, 12.39), with very low certainty. However, direct evidence showed non-significant TTR improvement (MD = 6.49; 95% CI: -3.09, 16.07, I2 = 96.1%). No differences across various strategies were observed in all-cause mortality, major bleeding, stroke, transient ischemic attack, and hospitalization.

Interpretation

PSM reduces the risk of major TE events compared with usual care, tends to improve anticoagulation control, and should be considered where appropriate.

Funding

Agency for Healthcare Research and Quality (grant ID 5R18HS027960).

Vitamin K Antagonist Reversal for Urgent Surgery Using 4-Factor Prothrombin Complex Concentrates: A Randomized Clinical Trial

Importance

Millions of people take vitamin K antagonists (VKAs). Some people who need urgent surgical procedures require rapid VKA reversal to prevent excessive intraoperative bleeding.

Objective

To evaluate the hemostatic noninferiority of an investigational 4-factor prothrombin complex concentrate (4F-PCC) to a control 4F-PCC for rapid VKA reversal before urgent surgery.

Design, Setting, and Participants

This phase 3, double-blind, noninferiority randomized clinical trial (LEX-209) was conducted in 24 hospitals in the US, Russia, Georgia, Belarus, Ukraine, and Romania from June 7, 2017, through November 8, 2021; the study was stopped in February 2022. Participants were adult patients taking VKA who had an international normalized ratio (INR) of 2 or higher and needed urgent surgery with a substantial bleeding risk (≥50 mL). Patients were randomized 1:1 to a single infusion of either the investigational 4F-PCC or the control 4F-PCC. Data analysis followed intention-to-treat and per-protocol approaches.

Interventions

Single intravenous infusion was dosed by body weight and baseline INR. A dose of 25, 35, or 50 IU/kg of investigational 4F-PCC or control 4F-PCC was administered for baseline INR of 2 to less than 4, 4 to 6, or over 6, respectively.

Main Outcome and Measure

The primary end point was hemostatic efficacy at surgery end. An independent adjudication board, blinded to the 4F-PCC treatment allocation, assessed hemostatic efficacy using an objective 4-point scale.

Results

A total of 208 patients (median [range] age, 67.5 [31-92] years; 118 males [56.7%]) received the investigational (n = 105) or the control (n = 103) 4F-PCC. The median (range) dose was 25 (16-50) IU/kg in the investigational group and 25 (15-50) IU/kg in the control group, with a median (range) infusion time of 12 (8-50) minutes and 13 (7-30) minutes and a median (range) time from infusion to surgery start of 1.42 (0.25-15.25) hours and 1.50 (0.42-18.50) hours, respectively. Baseline median (range) INR was 3.05 (1.97-21.10) in the investigational group and 3.00 (2.00-11.30) in the control group. In the intention-to-treat analysis, the investigational 4F-PCC was noninferior to the control 4F-PCC, resulting in effective hemostasis in 94.3% of patients vs 94.2% of patients (proportion difference, 0.001; 95% CI, -0.080 to 0.082; P < .001), meeting the prespecified noninferiority margin of 0.15. An INR of 1.5 or lower at 30 minutes after infusion occurred in 78.1% of patients in the investigational group vs 71.8% of patients in the control group (proportion difference, 0.063; 95% CI, -0.056 to 0.181). Thrombotic events (2.9% vs 0%, respectively) and mortality (4.8% vs 1.0%, respectively) were no different than expected for 4F-PCC use. One patient in each treatment group discontinued due to adverse events (cardiac disorders unrelated to 4F-PCC).

Conclusions and Relevance

This randomized clinical trial found that the investigational 4F-PCC was hemostatically noninferior to the control 4F-PCC for rapid VKA reversal in patients needing urgent surgery with considerable bleeding risk; the safety profile of these two 4F-PCCs was similar. These results support the investigational 4F-PCC as a therapeutic option for surgical patients requiring rapid VKA reversal.

Trial Registration

ClinicalTrials.gov Identifier: NCT02740335.

An ISHLT consensus statement on strategies to prevent and manage hemocompatibility related adverse events in patients with a durable, continuous-flow ventricular assist device

Life expectancy of patients with a durable, continuous-flow left ventricular assist device (CF-LVAD) continues to increase. Despite significant improvements in the delivery of care for patients with these devices, hemocompatability-related adverse events (HRAEs) are still a concern and contribute to significant morbility and mortality when they occur. As such, dissemination of current best evidence and practices is of critical importance. This ISHLT Consensus Statement is a summative assessment of the current literature on prevention and management of HRAEs through optimal management of oral anticoagulant and antiplatelet medications, parenteral anticoagulant medications, management of patients at high risk for HRAEs and those experiencing thrombotic or bleeding events, and device management outside of antithrombotic medications. This document is intended to assist clinicians caring for patients with a CF-LVAD provide the best care possible with respect to prevention and management of these events.

Advancements in the interventional therapy and nursing care on deep vein thrombosis in the lower extremities

This review examines recent advancements in interventional treatments and nursing care for lower extremity deep vein thrombosis (DVT), highlighting significant innovations and their clinical applications. It discusses the transition to novel anticoagulants such as Direct Oral Anticoagulants, which offer a safer profile and simplified management compared to traditional therapies. Mechanical interventions, including balloon angioplasty and venous stenting, are detailed for their roles in improving immediate and long-term vascular function in acute DVT cases. Furthermore, the use of image-guided techniques is presented as essential for enhancing the accuracy and safety of DVT interventions. Additionally, this study outlines advances in nursing care strategies, emphasizing comprehensive preoperative and postoperative evaluations to optimize patient outcomes. These evaluations facilitate tailored treatment plans, crucial for managing the complex needs of DVT patients. Long-term care strategies are also discussed, with a focus on patient education to ensure adherence to treatment protocols and to prevent recurrence. The synthesis aims to inform healthcare professionals about cutting-edge practices in DVT management, promoting a deeper understanding of how these advancements can be integrated into clinical practice. It also underscores the necessity for ongoing research to address challenges such as cost-effectiveness and patient compliance, ensuring that future treatments are both accessible and effective.

Discovery of Heparin Mimetic, Potent, and Selective Inhibitors of Human Clotting Factor XIIIa

Factor XIIIa (FXIIIa) is a cysteine transglutaminase that catalyzes the last step in the coagulation process. An anion-binding site inhibition of FXIIIa is a paradigm-shifting strategy that may offer key advantages of controlled inhibition. Such an approach is likely to lead to novel FXIIIa inhibitors that do not carry bleeding risks. We previously reported a flavonoid trimer-based allosteric inhibitor of FXIIIa with moderate potency and selectivity. To further advance this approach, we evaluated a series of 27 variably sulfonated heparin mimetics against human FXIIIa. Only 13 molecules exhibited inhibitory activity at the highest concentration tested with IC50 values of 2-286 μM. Specifically, inhibitor 16 demonstrated an IC50 value of 2.4 ± 0.5 μM in a bisubstrate, fluorescence-based trans-glutamination assay. It also demonstrated a significant selectivity over other clotting factors including thrombin, factor Xa, and factor XIa as well as other cysteine enzymes including papain and tissue transglutaminase 2. Inhibitor 16 did not affect the viability of three human cell lines at a concentration that is 5-fold its FXIIIa-IC50. The molecule had a very weak effect on the activated partial thromboplastin time of human plasma at a concentration of >700 μM, further supporting its functional selectivity. Importantly, molecule 16 inhibited FXIIIa-mediated polymerization of fibrin(ogen) in a concentration-dependent manner as shown by the gel electrophoresis experiment. Michaelis-Menten kinetics revealed that the molecule competes with the Gln-donor protein substrate, i.e., dimethylcasein, but not with the Lys-donor small substrate, i.e., dansylcadaverine. Molecular modeling studies revealed that this type of molecule likely binds to an anion-binding site comprising the basic amino acids of Lys54, Lys61, Lys73, Lys156, and Arg244 among others. Overall, our work puts forward a new anion-binding site, selective, nontoxic, sulfonated heparin mimetic FXIIIa inhibitor 16 for further development as an effective and safer anticoagulant.

Direct Oral Anticoagulants Exhibit Lower Risks of Mortality and Bleeding Compared to Vitamin K Antagonists in Atrial Fibrillation Patients on Chronic Hemodialysis: A Systematic Review and Meta-Analysis

This meta-analysis aimed to assess the outcomes of patients with atrial fibrillation undergoing chronic hemodialysis, comparing the effectiveness of direct oral anticoagulants (DOACs) and vitamin K antagonists. A systematic search was conducted across various databases including PubMed, Embase, and Google Scholar. Efficacy outcomes focused on the risk of stroke and mortality, whereas safety outcomes assessed the risk of bleeding. Review Manager generated forest plots for data synthesis. Statistical significance was set at P < 0.05, and random-effects models were used. Subgroup analysis identified the sources of heterogeneity. Nine studies met the inclusion criteria for the final analysis. The risk of all-cause stroke [risk ratio (RR): 0.64; 95% confidence interval (CI): 0.51-0.81; P = 0.0001; I2 = 0%], ischemic stroke (RR: 0.53; 95% CI: 0.29-0.96; P = 0.04; I2 = 0%), all-cause mortality (RR: 0.73; 95% CI: 0.60-0.88; P = 0.001; I2 = 71%), major bleeding (RR: 0.63; 95% CI: 0.52-0.76; P < 0.00001; I2 = 44%), gastrointestinal bleeding (RR: 0.67; 95% CI: 0.53-0.85; P = 0.0009; I2 = 36%), intracranial hemorrhage (RR: 0.57; 95% CI: 0.38-0.84; P = 0.004; I2 = 0%) were lower in the DOAC group compared with the vitamin K antagonist group. The risk of cardiovascular-related death (RR: 1.34; 95% CI: 0.69-2.60; P = 0.39; I2 = 0%), clinically relevant nonmajor bleeding (RR: 0.90; 95% CI: 0.75-1.08; P = 0.26; I2 = 28%), and hemorrhagic stroke (RR: 0.36; 95% CI: 0.06-2.24; P = 0.28; I2 = 10%) showed no significant differences. In conclusion, the risks of all-cause stroke, ischemic stroke, all-cause mortality, major bleeding, gastrointestinal bleeding, and intracranial hemorrhage in patients with atrial fibrillation undergoing chronic hemodialysis were lower in the DOAC group.

Dual Inhibition of Factor XIIa and Factor XIa Produces a Synergistic Anticoagulant Effect

ABSTRACT

Clinical practice shows that a critical unmet need in the field of thrombosis prevention is the availability of anticoagulant therapy without bleeding risk. Inhibitors against FXIa or FXIIa have been extensively studied because of their low bleeding risk. However, whether these compounds produce synergistic effects has not yet been explored. In this study, analyses of activated partial thromboplastin time in combination with the FXIa inhibitor PN2KPI and the FXIIa inhibitor Infestin4 at different proportions were performed using the SynergyFinder tool identifying synergistic anticoagulation effects. Both an FeCl 3 -induced carotid artery thrombosis mouse model and a transient occlusion of the middle cerebral artery mouse model showed that the combination of PN2KPI and Infestin4, which are 28.57% and 6.25% of the effective dose, respectively, significantly prevents coagulation, and furthermore, dual inhibition does not cause bleeding risk.

Clinical versus fixed warfarin dosing and the impact on quality of anticoagulation (The ClinFix trial)

Different dosing strategies exist to initiate warfarin, most commonly fixed warfarin dosing (FWD), clinical warfarin dosing (CWD), and genetic-guided warfarin dosing (GWD). Landmark trials have shown GWD to be superior when compared to FWD in the EU-PACT trial or CWD in the GIFT trial. COAG trial did not show differences between GWD and CWD. We aim to compare the anticoagulation quality outcomes of CWD and FWD. This is a prospective cohort study with a retrospective comparator. Recruited subjects in the CWD (prospective) arm were initiated on warfarin according to the clinical dosing component of the algorithm published in www.warfarindosing.org. The primary efficacy outcome was the percentage time in the therapeutic range (PTTR) from day 3 to 6 till day 28 to 35. The study enrolled 122 and 123 patients in the CWD and FWD, respectively. The PTTR did not differ statistically between CWD and FWD (62.2 ± 26.2% vs. 58 ± 25.4%, p = 0.2). There was also no difference between both arms in the percentage of visits with extreme subtherapeutic international normalized ratio (INR) (<1.5; 15 ± 18.3% vs. 16.8 ± 19.1%, p = 0.44) or extreme supratherapeutic INR (>4; 7.7 ± 14.7% vs. 7.5 ± 12.4%, p = 0.92). We conclude that CWD did not improve the anticoagulation quality parameters compared to the FWD method.

Effectiveness of Direct Oral Anticoagulants and Vitamin K Antagonists in Preventing Stroke in Patients With Atrial Fibrillation and Liver Cirrhosis: A Systematic Review and Meta-Analysis

Patients with atrial fibrillation and concurrent liver cirrhosis have been excluded from major clinical trials evaluating direct oral anticoagulants (DOACs) due to safety concerns. This has led to uncertainty regarding the optimal anticoagulant therapy in this population at high risk of thromboembolic events. We conducted a systematic review and meta-analysis to compare the effectiveness and safety of DOACs versus vitamin K antagonists (VKAs) in patients with atrial fibrillation and liver cirrhosis. Databases including Embase, MEDLINE/PubMed, and Web of Science were searched for relevant studies. The primary effectiveness outcome was stroke or systemic embolism, and the safety outcome was major bleeding events. A total of 10 studies were included in the meta-analysis. Compared to VKAs, the use of DOACs was associated with a significantly lower risk of stroke or systemic embolism (RR: 0.78, 95% CI: 0.65-0.92, p=0.005). The risk of all-cause mortality was comparable between the two groups (RR: 0.89, 95% CI: 0.74-1.07, p=0.23). Notably, DOACs demonstrated a significantly lower risk of major bleeding events (RR: 0.67, 95% CI: 0.61-0.73, p<0.01) compared to VKAs. This meta-analysis suggests that DOACs may be a favorable alternative to VKAs for the prevention of thromboembolic events in patients with atrial fibrillation and liver cirrhosis, with a lower risk of stroke or systemic embolism and major bleeding. However, further research is needed to establish optimal dosing strategies and assess the safety and efficacy of DOACs in patients with advanced liver disease.

Genetic polymorphisms and major bleeding risk during vitamin K antagonists treatment: The BLEEDS case-cohort

BACKGROUND

Major bleeding occurs annually in 1%-3% of patients on vitamin K antagonists (VKAs), despite close monitoring. Genetic variants in proteins involved in VKA response may affect this risk.

AIM

To determine the association of genetic variants (cytochrome P450 enzymes 2C9 [CYP2C9] and 4F2 [CYP4F2], gamma-glutamyl carboxylase [GGCX]) with major bleeding in VKA users, separately and combined, including vitamin K epoxide reductase complex subunit-1 (VKORC1).

METHODS

A case-cohort study was established within the BLEEDS cohort, which includes 16,570 patients who initiated VKAs between 2012 and 2014. We selected all 326 major bleeding cases that occurred during 17,613 years of follow-up and a random subcohort of 978 patients. We determined variants in CYP2C9, CYP4F2, GGCX, VKORC1 and evaluated the interaction between variant genotypes. Hazard ratios for major bleeding with 95% confidence intervals (95% CI) were estimated by weighted Cox regression.

RESULTS

Genotype was determined in 256 cases and 783 subcohort members. Phenprocoumon was the most prescribed VKA for both cases and the subcohort (78% and 75%, respectively). Patients with major bleeding were slightly older than subcohort patients. CYP4F2-TT carriership was associated with a 1.6-fold (95% CI 0.9-2.8) increased risk of major bleeding compared with CC-alleles, albeit not statistically significant. For the CYP2C9 and GGCX variants instead, the major bleeding risk was around unity. Carrying at least two variant genotypes in CYP2C9 (poor metabolizer), CYP4F2-TT, and VKORC1-AA was associated with a 4.0-fold (95%CI 1.4-11.4) increased risk, while carriers of both CYP4F2-TT and VKORC1-AA had a particularly increased major bleeding risk (hazard ratio 6.7, 95% CI 1.5-29.8) compared with carriers of CC alleles in CYP4F2 and GG in VKORC1. However, the number of major bleeding cases in carriers of multiple variants was few (8 and 5 patients, respectively).

CONCLUSIONS

CYP4F2 polymorphism was associated with major bleeding, especially in combination with VKORC1 genetic variants. These variants could be considered to further personalize anticoagulant treatment.

Risk of dentoalveolar surgery postoperative bleeding in patients taking direct oral anticoagulants and vitamin K antagonists: A prospective observational study

The aim of this study was to evaluate whether direct oral anticoagulants (DOAC) and vitamin K antagonists (VKA) increase the risk of postoperative bleeding after dentoalveolar surgery. Patients were classified into two groups: one taking DOAC and the other taking VKA with a therapeutic INR range. The control group comprised non-anticoagulated subjects. Participants were matched regarding dentoalveolar procedure. The primary predictor was anticoagulant status. The primary outcome was postoperative bleeding. The DOAC group comprised 77 patients, while the VKA group and control group each consisted of 103 participants. In each group, 103 dentoalveolar surgical procedures were conducted. Postoperative bleeding was recorded in 3/103 (2.9%), 5/103 (4.8%), and 1/103 (0.97%) occasions in the DOAC, VKA, and control groups, respectively, without significant difference (χ2; p = 0.54). The fully adjusted odds ratio for postoperative bleeding was 0.14 (CI 0.01-1.61; p = 0.05) for patients taking DOAC and 0.19 (CI 0.02-1.65; p = 0.285) for those taking VKA compared with non-anticoagulated controls. In conclusion, there was no increase in risk for clinically significant postoperative bleeding after dentoalveolar surgery in patients taking DOAC or VKA compared with non-anticoagulated subjects. Dentoalveolar surgery in patients taking DOAC and VKA can be performed safely without therapy cessation. The study was registered at Clinicaltrials.gov (NCT04505475).

The 2023 WSES guidelines on the management of trauma in elderly and frail patients

BACKGROUND

The trauma mortality rate is higher in the elderly compared with younger patients. Ageing is associated with physiological changes in multiple systems and correlated with frailty. Frailty is a risk factor for mortality in elderly trauma patients. We aim to provide evidence-based guidelines for the management of geriatric trauma patients to improve it and reduce futile procedures.

METHODS

Six working groups of expert acute care and trauma surgeons reviewed extensively the literature according to the topic and the PICO question assigned. Statements and recommendations were assessed according to the GRADE methodology and approved by a consensus of experts in the field at the 10th international congress of the WSES in 2023.

RESULTS

The management of elderly trauma patients requires knowledge of ageing physiology, a focused triage, including drug history, frailty assessment, nutritional status, and early activation of trauma protocol to improve outcomes. Acute trauma pain in the elderly has to be managed in a multimodal analgesic approach, to avoid side effects of opioid use. Antibiotic prophylaxis is recommended in penetrating (abdominal, thoracic) trauma, in severely burned and in open fractures elderly patients to decrease septic complications. Antibiotics are not recommended in blunt trauma in the absence of signs of sepsis and septic shock. Venous thromboembolism prophylaxis with LMWH or UFH should be administrated as soon as possible in high and moderate-risk elderly trauma patients according to the renal function, weight of the patient and bleeding risk. A palliative care team should be involved as soon as possible to discuss the end of life in a multidisciplinary approach considering the patient's directives, family feelings and representatives' desires, and all decisions should be shared.

CONCLUSIONS

The management of elderly trauma patients requires knowledge of ageing physiology, a focused triage based on assessing frailty and early activation of trauma protocol to improve outcomes. Geriatric Intensive Care Units are needed to care for elderly and frail trauma patients in a multidisciplinary approach to decrease mortality and improve outcomes.

Factor XI as a new target for prevention of thromboembolism in cardiovascular disease: a meta-analysis of randomized controlled trials

Anticoagulant therapy is a mainstay in the management of patients with cardiovascular disease. The use of conventional anticoagulants carries potential side effects, mainly bleeding. Drugs targeting Factor XI (FXI) have been investigated in randomized controlled trials as a new option with more favorable outcomes. A comprehensive literature search was conducted to identify relevant studies comparing FXI inhibitors to placebo or standard therapy. The primary outcomes were incidence of all bleeding events, major bleeding, and thromboembolism. Secondary outcomes included incidence of all adverse events (AE), serious AE, and all-cause mortality. A total of 11 studies involving 10,536 patients were included. FXI inhibitors were associated with a trend toward reduction of bleeding events and incidence of thromboembolism compared to the control group (placebo/standard therapy). There was no statistically significant difference between both groups in terms of adverse events and all-cause mortality. When compared to enoxaparin, FXI inhibitors significantly reduced the risk of bleeding events (RR = 0.42, 95% CI: 0.23-0.76, P = 0.004) and thromboembolism (RR = 0.59, 95% CI: 0.44-0.77, P = 0.001). On the other hand, when compared to DOACs, FXI inhibitors were associated with a significant reduction in bleeding events but not thromboembolism. Whereas, compared to placebo, FXI inhibitors did not increase the risk of bleeding events, adverse events, or all-cause mortality (P > 0.05). FXI inhibitors could be a safer and more potent option for prevention of thromboembolism than conventional therapy.

Reversal and resumption of anticoagulants in patients with anticoagulant-associated intracerebral hemorrhage

The use of anticoagulants has become more frequent due to the progressive aging population and increased thromboembolic events. Consequently, the proportion of anticoagulant-associated intracerebral hemorrhage (AAICH) in stroke patients is gradually increasing. Compared with intracerebral hemorrhage (ICH) patients without coagulopathy, patients with AAICH may have larger hematomas, worse prognoses, and higher mortality. Given the need for anticoagulant reversal and resumption, the management of AAICH differs from that of conventional medical or surgical treatments for ICH, and it is more specific. Understanding the pharmacology of anticoagulants and identifying agents that can reverse their effects in the early stages are crucial for treating life-threatening AAICH. When patients transition beyond the acute phase and their vital signs stabilize, it is important to consider resuming anticoagulants at the right time to prevent the occurrence of further thromboembolism. However, the timing and strategy for reversing and resuming anticoagulants are still in a dilemma. Herein, we summarize the important clinical studies, reviews, and related guidelines published in the past few years that focus on the reversal and resumption of anticoagulants in AAICH patients to help implement decisive diagnosis and treatment strategies in the clinical setting.

Drug-drug interactions with oral anticoagulants: information consistency assessment of three commonly used online drug interactions databases in Switzerland

Background: Toxicity or treatment failure related to drug-drug interactions (DDIs) are known to significantly affect morbidity and hospitalization rates. Despite the availability of numerous databases for DDIs identification and management, their information often differs. Oral anticoagulants are deemed at risk of DDIs and a leading cause of adverse drug events, most of which being preventable. Although many databases include DDIs involving anticoagulants, none are specialized in them. Aim and method: This study aims to compare the DDIs information content of four direct oral anticoagulants and two vitamin K antagonists in three major DDI databases used in Switzerland: Lexi-Interact, Pharmavista, and MediQ. It evaluates the consistency of DDIs information in terms of differences in severity rating systems, mechanism of interaction, extraction and documentation processes and transparency. Results: This study revealed 2'496 DDIs for the six anticoagulants, with discrepant risk classifications. Only 13.2% of DDIs were common to all three databases. Overall concordance in risk classification (high, moderate, and low risk) was slight (Fleiss' kappa = 0.131), while high-risk DDIs demonstrated a fair agreement (Fleiss' kappa = 0.398). The nature and the mechanism of the DDIs were more consistent across databases. Qualitative assessments highlighted differences in the documentation process and transparency, and similarities for availability of risk classification and references. Discussion: This study highlights the discrepancies between three commonly used DDI databases and the inconsistency in how terminology is standardised and incorporated when classifying these DDIs. It also highlights the need for the creation of specialised tools for anticoagulant-related interactions.

Attainment of Target in Therapeutic Range of International Normalized Ratio and Correlates Among Patients on Warfarin Therapy at Jimma Medical Center, Jimma, Ethiopia

PURPOSE

Warfarin is effective therapy to prevent thromboembolic complications of venous thromboembolism, atrial fibrillation, and cardiac thrombus, among valvular heart diseases, including in patients treated with prostheses and/or repair. Its optimum effect is achieved when the international normalized ratio (INR) is in the target therapeutic range, but a subtherapeutic level increases risk of thromboembolism and complications. This study aimed to assess the attainment of target therapeutic range, proportion, and factors associated with subtherapeutic level of warfarin.

METHODS

A hospital-based cross-sectional study was conducted at Jimma Medical Center in Jimma, Ethiopia, from October 1, 2020 through December 30, 2021. All patients on warfarin and attending Medical Follow-Up Clinics of Jimma Medical Center during the study period were included. Data were collected using structured questionnaires and then analyzed using EpiData Manager software, version 3.1 (EpiData Association). χ2 Tests and logistic regression models were used to assess relationships among variables.

FINDINGS

Of 196 patients on warfarin, ∼60% were taking it for atrial fibrillation, followed by deep venous thrombosis, women accounted for 61.7% of patients, and mean (SD) age was 43 (7) years. Most patients (61.7%) lived in rural areas and 44.9% farmed to earn a living. Most of the study participants (51.5%) had a very low monthly income of less than USD50. Most of the patients (n = 107 [54.6%]) were advised on dietary selections while on warfarin and approximately two-thirds (n = 70 [65.4%]) were adherent to the advice. Most participants (n = 118 [60.2%]) were poorly adherent to warfarin therapy and more than two-thirds of them discontinued warfarin for financial reasons. Mean (SD) duration of warfarin therapy was 15.53 (18.92) months (range 1-90 months). Most of the respondents (n = 109 [55.6%]) had subtherapeutic INR and 21 (10.7%) were in the supratherapeutic range. Although the mean (SD) time in therapeutic range was 25.03% (24.17% [range 0-80%]), in most patients (n = 166 [84.7%]), it was <60%. Poor adherence (adjusted odds ratio = 6.13; 95% CI, 3.31-28.10), shorter duration of warfarin (<12 months; adjusted odds ratio = 0.104; 95% CI, 0.012-0.875), and presence of comorbidity (adjusted odds ratio = 0.035; 95% CI, 0.004-0.323) were significantly associated with subtherapeutic INR.

IMPLICATIONS

Attainment of therapeutic INR among patients on warfarin therapy is suboptimal. This was evidenced by a significant number of patients with low time in therapeutic range, as well as INR. Poor adherence to warfarin therapy, shorter duration since initiation of warfarin, and presence of comorbid illnesses were significantly associated with subtherapeutic INR. This can lead to complications of atrial fibrillation, including thrombus formation and subsequent cardioembolic stroke, venous thromboembolism, and others, leading to morbidity, increased mortality, and poor quality of life. Therefore, providing health education and treatment for comorbidities may improve adherence, which may also improve attainment of therapeutic INR and reduce complications and improve quality of life.

Relationship of Warfarin and Apixaban with Vascular Function in Patients with Atrial Fibrillation

INTRODUCTION

Atrial fibrillation (AF) is associated with endothelial damage/dysfunction. Herein, we tested the hypothesis that brachial artery flow-mediated dilation (FMD) is superior in AF patients taking apixaban compared to warfarin.

METHODS

AF patients on apixaban (n = 46; 67 [7] years; mean [standard deviation]; 15 women) and warfarin (n = 27; 73 [9] years (p < 0.01); 11 women) were recruited. Duplex Doppler ultrasound imaging was undertaken during baseline (2 min), cuff inflation (5 min), and following cuff deflation (3 min). FMD was defined as peak increase in brachial artery diameter following cuff deflation and analysed as percentage change in diameter, as a ratio of FMD, shear rate area under the curve (SRAUC; FMD-to-SRAUC), and using SRAUC as a covariate (FMDSR).

RESULTS

Baseline artery diameter (4.96 [1.14] vs. 4.89 [0.88] mm), peak diameter (5.12 [1.17] vs. 5.14 [0.93] mm), and FMDSR (3.89 [3.62] vs. 4.80 [3.60] %) were not different between warfarin and apixaban (p > 0.05; analysis of covariance with age, CHA2DS2-VASc, years since AF diagnosis, number of diabetics, alcohol drinkers, and units of alcohol consumed per week as covariates). Stepwise multiple regression identified independent association of fibrillation, hypertension, and increased age with FMD.

CONCLUSION

AF patients on warfarin and apixaban exhibit similar endothelium-dependent vasodilation. Increased blood pressure negatively impacts vasodilator capacity in AF patients.

New Triazole-Based Potent Inhibitors of Human Factor XIIa as Anticoagulants

Factor XIIa (FXIIa) functions as a plasma serine protease within the contact activation pathway. Various animal models have indicated a substantial role for FXIIa in thromboembolic diseases. Interestingly, individuals and animals with FXII deficiency seem to maintain normal hemostasis. Consequently, inhibiting FXIIa could potentially offer a viable therapeutic approach for achieving effective and safer anticoagulation without the bleeding risks associated with the existing anticoagulants. Despite the potential, only a limited number of small molecule inhibitors targeting human FXIIa have been documented. Thus, we combined a small library of 32 triazole and triazole-like molecules to be evaluated for FXIIa inhibition by using a chromogenic substrate hydrolysis assay under physiological conditions. Initial screening at 200 μM involved 18 small molecules, revealing that 4 molecules inhibited FXIIa more than 20%. In addition to being the most potent inhibitor identified in the first round, inhibitor 8 also exhibited a substantial margin of selectivity against related serine proteases, including factors XIa, Xa, and IXa. However, the molecule also inhibited thrombin with a similar potency. It also prolonged the clotting time of human plasma, as was determined in the activated partial thromboplastin time and prothrombin time assays. Subsequent structure-activity relationship studies led to the identification of several inhibitors with submicromolar activity, among which inhibitor 22 appears to demonstrate significant selectivity not only over factors IXa, Xa, and XIa, but also over thrombin. In summary, this study introduces novel triazole-based small molecules, specifically compounds 8 and 22, identified as potent and selective inhibitors of human FXIIa. The aim is to advance these inhibitors for further development as anticoagulants to provide a more effective and safer approach to preventing and/or treating thromboembolic diseases.

Real-World Safety and Effectiveness of a 4-Factor Prothrombin Complex Concentrate in Japanese Patients Experiencing Major Bleeding: A Post-marketing Surveillance Study

INTRODUCTION

Limited data are available regarding the safety and effectiveness of 4-factor prothrombin complex concentrate (4F-PCC) in patients experiencing major hemorrhage or requiring expeditious surgical intervention, both globally and within Japan.

METHODS

We executed a prospective, observational post-marketing surveillance study of patients receiving 4F-PCC for the first time between September 19, 2017 and August 15, 2018 in Japan. Patients were subjected to a comprehensive follow-up for a duration of 4 weeks.

RESULTS

Of 1381 eligible patients, 1271 (92%) received a vitamin K antagonist. Among these, 58% were aged ≥ 75 years, 49% manifested atrial fibrillation, 17% presented with valvular heart disease, and 6% exhibited venous thromboembolism. The median (range) international normalized ratio was 2.67 (0.96-27.11) at baseline and 1.21 (0.45-6.61) at first measurement post-administration of 4F-PCC. The most common reason for 4F-PCC administration was intracranial hemorrhage (59.6%), followed by gastrointestinal bleeding (6.6%). Hemostatic effectiveness was achieved in 85.8% of patients. The incidences of adverse drug reactions (ADRs) and serious ADRs were 3.9% and 2.8%, respectively. Thromboembolic events (TEEs) occurred in 20 (1.5%) patients, with a mean onset of 10 days. The majority of TEEs were classified as nervous system disorders (55%). At the time of TEE, only 13% of patients resumed anticoagulant therapy.

CONCLUSION

The incidence of TEEs following treatment with 4F-PCC did not surpass those observed in phase 3 trials. No novel safety signals were identified. The safety and effectiveness of 4F-PCC in Japanese real-world practice were in harmony with the observations of prior studies.

Comparative safety review of antithrombotic treatment options for patients with atrial fibrillation undergoing percutaneous coronary intervention

INTRODUCTION

Balancing antithrombotic therapy for atrial fibrillation (AF) patients undergoing percutaneous coronary intervention (PCI) remains a clinical challenge due to coexisting thrombogenic risks. This review emphasizes the delicate balance required to prevent ischemic events while minimizing bleeding complications, particularly in the context of risk assessment.

AREAS COVERED

This review spans from 2010 to October 2023, exploring the complexities of antithrombotic management for AF patients undergoing PCI. It stresses the need for personalized treatment decisions to optimize antithrombotic therapies effectively.

EXPERT OPINION

The evolving evidence supports double antithrombotic therapy (DAT) over triple antithrombotic therapy (TAT) for these patients, showcasing a more favorable safety profile without compromising efficacy. Non-vitamin K antagonist oral anticoagulant (NOAC)-based DAT strategies exhibit superiority in reducing major bleeding events while effectively preventing ischemic events. Recommendations from the 2023 European Society of Cardiology (ESC) Guidelines advocate for NOAC-based DAT post-PCI, endorsing safer antithrombotic profiles.Challenges persist for specific patient categories requiring both oral anticoagulants and antiplatelets, necessitating personalized approaches. Future advances in intravascular imaging and novel coronary stent technologies offer promising avenues to optimize outcomes and influence antithrombotic strategies in AF-PCI patients.

Antithrombotic Therapy Following Structural Heart Disease Interventions: Current Status and Future Directions

Interventions in structural heart disease cover many catheter-based procedures for congenital and acquired conditions including valvular diseases, septal defects, arterial or venous obstructions, and fistulas. Among the available procedures, the most common are aortic valve implantation, mitral or tricuspid valve repair/implantation, left atrial appendage occlusion, and patent foramen ovale closure. Antithrombotic therapy for transcatheter structural heart disease interventions aims to prevent thromboembolic events and reduce the risk of short-term and long-term complications. The specific approach to antithrombotic therapy depends on the type of intervention and individual patient factors. In this review, we synopsize contemporary evidence on antithrombotic therapies for structural heart disease interventions and highlight the importance of a personalized approach. These recommendations may evolve over time as new evidence emerges and clinical guidelines are updated. Therefore, it's crucial for healthcare professionals to stay updated on the most recent guidelines and individualize therapy based on patient-specific factors and procedural considerations.

International Normalized Ratio Predicts Recurrence and Bleeding in Patients With Acute Venous Thromboembolism Who Undergo Direct Oral Anticoagulants

Prothrombin time/international normalized ratio (PT/INR) is related to both antithrombotic effect and risk of bleeding. Its role in the prediction of venous thromboembolism (VTE) recurrence and bleeding for patients with acute VTE who undergo direct oral anticoagulants (DOACs) treatment is unclear, despite previous studies revealed some association between them. The predictive efficiency of INR for VTE recurrence and bleeding were analyzed in a retrospective cohort with VTE patients who underwent DOACs treatment. Then its predictive efficiency for VTE recurrence and bleeding were validated in a prospective cohort with the acquired cutoffs range, and compared with anti-Xa level, DASH and VTE-BLEED scores. In the retrospective cohort (n = 1083), the sensitivity and specificity of INR for the prediction of VTE recurrence were 79.4% and 92.8%, respectively. The area under the curve (AUC) was 0.881 (0.803-0.960)(P = .025). The cutoff value of INR was 0.9. The sensitivity and specificity of INR for the prediction of bleeding were 85.7% and 77.9%, respectively. The AUC was 0.876 (0.786-0.967)(P < .001). The cutoff value of INR was 2.1. In the prospective cohort (n = 202), the calibration showed that there were 4 (50%) patients with VTE recurrence, 156 (97.5%) patients with non-recurrence and bleeding (non-R&B), and 20 (58.8%) patients with bleeding in the low (INR < 0.9)(n = 8), intermediate (0.9 ≤ INR ≤ 2.1)(n = 160), and high (INR > 2.1)(n = 34) groups, respectively. The baseline PT/INR value at the initiation of DOACs treatment is an independent predictor for VTE recurrence and bleeding in patients with acute VTE who undergo DOACs treatment.

Comparison of vitamin K and non-vitamin K oral anticoagulants and the bleeding frequency in the emergency department

INTRODUCTION

Safety studies of anticoagulant therapy have so far been conducted on many subjects in controlled conditions (i.e., clinically monitored) and demonstrated the noninferiority of new ones over old anticoagulant drugs. Data on the propositions for the presence of symptoms and signs of bleeding among various anticoagulants in the emergency department indicate that these data do not match the data published so far.

AIM

The aim of the study was to investigate the differences in the frequency of bleeding and bleeding-related symptoms as a reason for emergency department attendance in patients on anticoagulant therapy.

METHODS

The study included patients from the emergency department of University Hospital for one year, who were on anticoagulant therapy and who met the inclusion criteria. Out of a total of 595 patients, 409 were on warfarin (68.74%), and the rest were taking direct oral anticoagulants (DOAC): dabigatran 71 (11.93%), rivaroxaban 66 (11.09%) and apixaban 49 (8.23%).

RESULTS

Out of 409 patients taking warfarin, 34.4% were adequately anticoagulated with the frequency of bleeding 13.7%, while in 57.2% of patients, PT INR was higher than the reference values with the frequency of bleeding 15.0%. A comparison between all DOAC groups and adequately anticoagulated warfarin patients in the frequency of bleeding and bleeding-related symptoms as a reason for emergency attendance yielded a difference that was marginally statistically significant (Pearson Chi-Square = 7.554, p = 0.052).

CONCLUSION

Monitoring the frequency of bleeding and bleeding-related symptoms in patients on oral anticoagulant therapy as a reason for emergency department attendance may be a new safety and efficacy factor in real-life patient scenarios.

The Challenge of Anticoagulation in Liver Cirrhosis

Background

Advanced liver diseases are characterized by a number of changes in the hemostatic system. Due to the occurrence of bleeding events in patients with liver cirrhosis, there seems to be a hesitance to the administration of anticoagulant medications. This review summarizes challenges, recommendations, and current developments of anticoagulation in the cirrhotic patient.

Summary

The risk of thrombotic events in patients with liver cirrhosis is at least as high as in patients with healthy liver function if not even higher. Standard laboratory markers do not truly reflect the complexity of changes that take place in the coagulative system and therefore cannot be used as a reference for risk of thrombosis or hemorrhage. Potential options for anticoagulant therapy are heparins, vitamin K antagonists, and direct-acting oral anticoagulants which come with differences in safety, application, possible side effects, and data availability for the patient cohort.

Key Message

The administration of anticoagulation can be beneficial in patients with liver disease if the indication is present and bleeding prophylaxis has been established. Direct-acting oral anticoagulants appear to be a promising new approach with many improvements compared to conventional substances. Nevertheless, there is a need for further data and prospective trials on the use in patients with liver cirrhosis.

Anti-Xa Activity Monitoring for Optimizing Rivaroxaban Dosage in Chinese Patients with Cerebral Venous Thrombosis

BACKGROUND

Rivaroxaban, a direct Factor Xa inhibitor, is commonly used for cerebral venous thrombosis (CVT) correction. However, pharmacokinetic differences in Chinese may vary in sensitivity and tolerance, resulting in either insufficient or excessive anticoagulation. Herein, the optimizing dosages of rivaroxaban in Chinese patients with CVT were analyzed based on monitoring anti-Xa activity dynamically, to maintain therapeutic efficacy and reduce rivaroxaban-related bleeding.

METHODS

A real-world cohort study was conducted involving 112 CVT patients in Xuanwu Hospital, from August 2021 through January 2024. Patients were grouped according to their doses of rivaroxaban use (5, 10, 15, and 20 mg daily) based on dynamic plasma anti-Xa activity monitored using the chromogenic anti-Xa assay. Plasma levels of anti-Xa activity reached the therapeutic range, bleeding events and the dosage of rivaroxaban among these groups were analyzed.

RESULTS

The ratios of the patients whose plasma anti-Xa levels reached the standard therapeutic level (0.3-0.7 IU/mL) between the cohorts less than 20 mg/d and 20 mg/d showed no statistical difference, and no significant disparities were observed among 5, 10, 15, and 20 mg/d dose groups. There was a discernible increase in the proportion of patients with bleeding events in the 20 mg/d group, even though the results did not reach a statistical difference. Meanwhile, in patients with bleeding events, their plasma anti-Xa levels could exceed 0.7 IU/mL.

CONCLUSION

Sensitivity and tolerance to rivaroxaban in Chinese may vary. Individualized therapy dosage under the guidance of anti-Xa activity monitoring may not only guarantee anticoagulation effect, but also reduce rivaroxaban-related bleeding events.

Anticoagulant therapy in orthopedic surgery - a review on anticoagulant agents, risk factors, monitoring, and current challenges

Orthopedic surgeries are associated with high-risk of thromboembolism which occurs in 40% to 60% of orthopedic patients in the absence of thromboprophylaxis. Conventionally heparin anticoagulants were used for thromboprophylaxis and currently direct oral anticoagulants (DOACs) are widely used due to their minimal complexity. Anticoagulant use carries bleeding risk and requires optimal laboratory monitoring through conventional thrombin-based assays, anti-Xa assay, anti-IIa assay and contemporary ecarin chromogenic assay (ECA) and rotational thromboelastometry. Monitoring requires multiple hospital visits and hence, the development of point-of-care assays is gaining momentum. Also, a thorough risk assessment model (RAM) is necessary for successful anticoagulant therapy since it enables personalized approach for better thromboprophylaxis outcomes. Despite welcoming changes, lack of guideline consensus, population-based thromboprophylaxis, deficiencies in risk stratification and non-adherence are still a concern. Stronger clinical and process support system with uniform guidelines approaches and patient-specific RAM can aid in the successful implementation of anticoagulant therapy.

Evaluation of Machine Learning Approaches for Predicting Warfarin Discharge Dose in Cardiac Surgery Patients: Retrospective Algorithm Development and Validation Study

BACKGROUND

Warfarin dosing in cardiac surgery patients is complicated by a heightened sensitivity to the drug, predisposing patients to adverse events. Predictive algorithms are therefore needed to guide warfarin dosing in cardiac surgery patients.

OBJECTIVE

This study aimed to develop and validate an algorithm for predicting the warfarin dose needed to attain a therapeutic international normalized ratio (INR) at the time of discharge in cardiac surgery patients.

METHODS

We abstracted variables influencing warfarin dosage from the records of 1031 encounters initiating warfarin between April 1, 2011, and November 29, 2019, at St Michael's Hospital in Toronto, Ontario, Canada. We compared the performance of penalized linear regression, k-nearest neighbors, random forest regression, gradient boosting, multivariate adaptive regression splines, and an ensemble model combining the predictions of the 5 regression models. We developed and validated separate models for predicting the warfarin dose required for achieving a discharge INR of 2.0-3.0 in patients undergoing all forms of cardiac surgery except mechanical mitral valve replacement and a discharge INR of 2.5-3.5 in patients receiving a mechanical mitral valve replacement. For the former, we selected 80% of encounters (n=780) who had initiated warfarin during their hospital admission and had achieved a target INR of 2.0-3.0 at the time of discharge as the training cohort. Following 10-fold cross-validation, model accuracy was evaluated in a test cohort comprised solely of cardiac surgery patients. For patients requiring a target INR of 2.5-3.5 (n=165), we used leave-p-out cross-validation (p=3 observations) to estimate model performance. For each approach, we determined the mean absolute error (MAE) and the proportion of predictions within 20% of the true warfarin dose. We retrospectively evaluated the best-performing algorithm in clinical practice by comparing the proportion of cardiovascular surgery patients discharged with a therapeutic INR before (April 2011 and July 2019) and following (September 2021 and May 2, 2022) its implementation in routine care.

RESULTS

Random forest regression was the best-performing model for patients with a target INR of 2.0-3.0, an MAE of 1.13 mg, and 39.5% of predictions of falling within 20% of the actual therapeutic discharge dose. For patients with a target INR of 2.5-3.5, the ensemble model performed best, with an MAE of 1.11 mg and 43.6% of predictions being within 20% of the actual therapeutic discharge dose. The proportion of cardiovascular surgery patients discharged with a therapeutic INR before and following implementation of these algorithms in clinical practice was 47.5% (305/641) and 61.1% (11/18), respectively.

CONCLUSIONS

Machine learning algorithms based on routinely available clinical data can help guide initial warfarin dosing in cardiac surgery patients and optimize the postsurgical anticoagulation of these patients.

Clinical, economic, and humanistic impact of a multidisciplinary medication review with follow-up for anticoagulated patients treated with vitamin K antagonists in primary care: A cluster randomised controlled trial

BACKGROUND

Interdisciplinary collaboration between general practitioner, nurses and pharmacists can favour the control of patients treated with vitamin K antagonists (VKA), increasing their safety and effectiveness. The aim of the study was to evaluate the impact of pharmaceutical interventions on patients treated with VKA within the framework of a Pharmacotherapeutic Follow-up service on clinical, economic and humanistic outcomes.

METHODS

Controlled and randomized study in patients from two health areas of Zaragoza in treatment with VKA with Time in Therapeutic Range (TTR) according to the Rosendaal method less than 70% in the last 6 months. Patients were recruited at the pharmacy and assigned to two groups: control and intervention. A Pharmacotherapeutic Follow-up Program was established for the intervention group for 6 months. The outcome variables were INR stability, pharmacological adherence, vitamin K intake, knowledge about the use of acenocoumarol, quality of life, satisfaction with treatment, associated costs and avoided costs. A descriptive analysis was performed, and the Students' T test or Mann-Whitney U test was used for the association between quantitative variables and Chi-square or Fisher's test for qualitative variables.

RESULTS

A total of 123 patients were included, 65 in the intervention group (IG) and 58 in the control group (CG). A total of 108 interventions were conducted (1.7 interventions/patient) and the most common were those related to the proper taking of medications (41.0%). In IG, TTR (p = 0.019), adherence to treatment (p = 0.038) and knowledge about acenocoumarol (p = 0.031) improved, compared to CG. A higher proportion of patients in IG achieved a TTR>65% (p = 0.024). In addition, patients whose interventions were accepted by the physician (p = 0.027) and those who received vitamin K optimization interventions (p = 0.003) achieved TTR>65% in greater proportion.

CONCLUSIONS

Community pharmacist medication review, in collaboration with general practitioners improve knowledge and adherence of patients treated with oral anti-vitamin K agents and enhances the achievement of their therapeutic INR ranges. Investment needed to achieve this clinical impact is low and patient satisfaction is high.

TRIAL REGISTRATION

This study has been registered with Clinical Trials.gov dated 25/05/2017: NCT03154489.

Global Research Hotspots in Venous Thromboembolism Anticoagulation: A Knowledge-Map Analysis from 2012 to 2021

Background

Venous thromboembolism (VTE) is a common cardiovascular disease that seriously threatens human lives. Anticoagulant therapy is considered to be the cornerstone of VTE treatment. An increasing number of studies has been updated in the VTE anticoagulation field. However, no bibliometric analyses have assessed these publications comprehensively. Therefore, our study aimed to analyze the global status, hotspots, and trends of anticoagulant therapy for VTE.

Methods

The relevant literature on VTE anticoagulation published between 2012 and 2021 was retrieved and collected from the Web of Science Core Collection database. VOSviewer, Cooccurrence Matrix Builder, gCLUTO, and some online visualization tools were adopted for bibliometric analysis.

Results

A total of 15,152 related articles were retrieved. In recent years, the research output of VTE anticoagulation gradually increased. The United States was the most productive country. International cooperation is concentrated in North America and Europe; the most influential documents, journals, authors, and organizations were also from these two continents. Research hotspots mainly focus on clinical guidelines, VTE in special populations, non-vitamin K oral anticoagulants (NOACs), and parenteral anticoagulation. The research frontiers and trends include the assessment of NOACs and the antithrombotic management of VTE complicated with coronavirus disease 2019 (COVID-19).

Conclusion

This bibliometric analysis provides a systematic overview of the VTE anticoagulation research, which will facilitate researchers to better understand the situation of VTE anticoagulation. Future studies should be dedicated to NOACs application and VTE-combined COVID-19 patients.

Risk of Bleeding in Liver Cirrhosis Receiving Direct Oral Anticoagulants: A Systematic Review and Meta-analysis

BACKGROUND

 Direct oral anticoagulants (DOACs) are effective for the management of thromboembolic disorders. However, bleeding remains a major concern in cirrhotic patients receiving DOACs.

METHODS

 PubMed, EMBASE, and Cochrane Library databases were searched. The incidence of bleeding episodes in cirrhotic patients receiving DOACs was pooled. Odds ratios (ORs) were calculated to compare the incidence of bleeding episodes in cirrhotic patients who received DOACs versus those who received conventional anticoagulants and did not receive anticoagulants.

RESULTS

 Twenty-nine studies were included. All bleeding, major bleeding, fatal bleeding, gastrointestinal bleeding, and intracranial hemorrhage episodes were observed in 310/2,469, 100/1,388, 2/611, 166/1,886, and 5/1,147 cirrhotic patients receiving DOACs, respectively. Their pooled incidences were 13, 6, 0, 8, and 0%, respectively. They became higher in subgroup analyses of studies with advanced age, a longer treatment duration, and Child-Turcotte-Pugh class C. Compared with conventional anticoagulants, DOACs were associated with lower incidences of all bleeding (OR = 0.71, 95% confidence interval [CI] = 0.52-0.98) and major bleeding (OR = 0.55, 95% CI = 0.37-0.83) in cirrhotic patients, but not those of fatal bleeding (OR = 0.21, 95% CI = 0.04-1.28), gastrointestinal bleeding (OR = 0.78, 95% CI = 0.52-1.17), or intracranial hemorrhage (OR = 0.36, 95% CI = 0.12-1.12). The incidences of all bleeding (OR = 1.04, 95% CI = 0.22-4.79) and major bleeding (OR = 0.96, 95% CI = 0.26-3.61) did not significantly differ between cirrhotic patients with portal vein thrombosis (PVT) who received DOACs and those who did not receive anticoagulants.

CONCLUSION

 DOACs carry a low risk of bleeding in liver cirrhosis. Age, treatment duration, and Child-Turcotte-Pugh class may be associated with bleeding in cirrhotic patients receiving DOACs. The risk of bleeding is not increased by DOACs in cirrhotic patients with PVT.

Identification of thrombin inhibiting antithrombin-III like protein from Punica granatum using in silico approach and in vitro validation of thrombin inhibition activity in crude protein

Thrombosis is characterized by the formation of clots in the blood vessels. Antithrombin-III deficiency in the blood causes thrombus formation. Supplementing antithrombin-III may serve as anticoagulant therapy. In the present studies, an antithrombin like Protein from Punica granatum has been identified and characterized using in silico approach. Based on sequence homology, an ALPP was selected depending upon its highest binding affinity of -41.28 kcal/mol with thrombin. Thrombin structure complexed with ALPP was docked with TAME using AutoDock Vina. No binding was observed for TAME at Ser195 of thrombin. MD simulation (50 ns) was performed to evaluate the flexibility and stability of docked complexes. In vitro assays with crude protein showed 78% thrombin inhibition at 5 µg and calculated IC50 value was 0.188 µg. The presence of thrombin inhibitors in crude protein was also confirmed by reverse zymography. Thus, it is very likely that the protein identified from P. granatum may act as thrombin inhibitor.

The Impact of Antithrombotic Medications on Postoperative Bleeding Events Following Hemorrhoidectomy

BACKGROUND

Bleeding complications are a risk associated with hemorrhoid procedures. Despite the prevalence of anticoagulant and antiplatelet therapies, including newer direct oral anticoagulants (DOACs) in the aging patient population there is a paucity of data regarding the impact of the use of antithrombotic therapy (AT) especially DOACs, on bleeding complications of hemorrhoid procedures.

METHODS

We retrospectively reviewed charts of patients who had undergone a total of 1152 procedures, including hemorrhoid excision and ligation, at a single institution in the years 2016-2018. We noted whether they were prescribed AT, the indication for therapy, perioperative medication management, whether a PBE occurred, and how the PBE was managed.

RESULTS

PBE's were noted in 5.92% of patients on ATs, as opposed to 2.66% of patients not on ATs (P = .014.) The odds ratio of having a PBE when on ATs vs not on ATs is 2.3 (95% CI 1.21 to 4.38, P = .011). Seven out of 40 (17.5%) total PBE's required hospital admission or repeat procedure, and this was not associated with AT use. Surprisingly, although males represented most of the patients on ATs, females were statistically more likely to have a PBE following a hemorrhoidectomy if on ATs.

DISCUSSION

Patients on AT have an elevated risk of PBE compared to patients not on AT. No significant difference was found between the two groups when considering only those PBE's severe enough to require hospital admission or repeat procedure. Further research is required to establish clear guidelines regarding the perioperative management of AT for hemorrhoid procedures.

Bleeding Risk in Hemodialysis Patients

Cardiovascular diseases are highly prevalent among patients on dialysis. For these diseases, antiplatelets and antithrombotic therapies including heparin, vitamin K antagonists, and direct oral anticoagulants, are being used. However, the benefit-risk balance of these therapies could differ for dialysis patients compared with the general population. This review article focuses on the bleeding risk associated with the use of heparin, antiplatelets, vitamin K antagonists, and direct oral anticoagulants in patients receiving hemodialysis.

Anticoagulant therapy in COVID-19: A narrative review

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can manifest itself in several ways, including coagulopathy and thrombosis. These complications can be the first and sometimes only manifestations of SARS-CoV-2 infection and can occur early or late in the course of the disease. However, these symptoms are more prevalent in hospitalized patients with venous thromboembolism, particularly those admitted to intensive care units. Moreover, various forms of arterial and venous thrombosis, or micro- or macro-vasculature embolisms, have been reported during the current pandemic. They have led to harmful consequences, such as neurological and cardiac events, nearly all resulting from the hypercoagulable state caused by this viral infection. The severe hypercoagulability observed in patients with COVID-19 accounts for most cases of the disease that become critical. Therefore, anticoagulants seem to be one of the most vital therapeutics for treating this potentially life-threatening condition. In the current paper, we present a thorough review of the pathophysiology of COVID-19-induced hypercoagulable state and the use of anticoagulants to treat SARS-CoV-2 infections in different patient groups, as well as their pros and cons.

Assessment of the relationship between the level of patient knowledge on warfarin therapy and the quality of oral anticoagulation: A systematic review and meta-analysis

The present study aimed to investigate the relationship between the level of patient knowledge on warfarin therapy and the quality of oral anticoagulation. This is a systematic review and meta-analysis written on the basis of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Searches at MEDLINE, EMBASE, Scopus and LILACS electronic databases were carried out on February 13, 2023, using the descriptors "Patient Medication Knowledge", "Patient Education as Topic", "Health Education", "Patient Education" and Warfarin. The steps of selection, data extraction and quality analysis of articles were performed independently by two reviewers. The analysis was performed considering patient knowledge as a possible modifier of time in therapeutic range (TTR). The meta-analysis included studies that reported the correlation coefficient (Pearson or Spearman) between patient knowledge and TTR. A subgroup analysis was performed according to questionnaires employed to measure patient knowledge. Twelve studies were selected with an overall sample size of 7634 participants and mean age 58.2 (standard deviation (SD)±12,8) years. Eleven (92.0%) cross-sectional studies. The mean TTR was 57.8% (SD±11,3%) and the average level of knowledge was 60.4%. The meta-analysis indicated that patient level of knowledge on warfarin therapy was moderately associated with TTR (rs = 0.435; 95% confidence interval (CI) = 0.163-0.645; I2 = 96%). Subgroup analysis indicated association between knowledge level and TTR in studies employing the OAK test (rs = 0.617; 95% CI = 0.192-0.847; I2 = 97%) and the AKA (rs = 0.269; 95% CI = 0.002 to 0.501; I2 = 94%). However, the subgroup analysis presented no significant difference between them (p = 0.14). The meta-regression showed a non-significant negative effect of age on the correlation (estimate = -0.028, 95% CI = -0.073 to 0.016, p = 0.207). No publication bias was noted (p = 0.881). To our knowledge, this is the first systematic review and meta-analysis gathering evidence about the relationship between the level of patient knowledge on oral anticoagulation with warfarin and TTR. The implementation of structured and patient-centered educational interventions is essential to effectively increase the level of patient knowledge and, thus, to improve the quality and safety of warfarin therapy. Systematic review registration number: PROSPERO CRD42023398030.

Influence of polymorphisms in CYP2C9, VKORC1, MDR1 and APOE genes on the warfarin maintenance dose in Brazilian patients

Background: Polymorphisms in the CYP2C9, VKORC1, MDR1 and APOE genes may impact warfarin dose. Aim: To investigate the influence of sociodemographic, clinical factors and polymorphisms *1, *2 and *3 for CYP2C9, -1639G>A for VKORC1, 3435C>T for MDR1, and ϵ2, ϵ3 and ϵ4 for APOE genes on the mean weekly warfarin maintenance dose in adults. Methods: This cross-sectional study recruited a calculated sample of 315 patients in three anticoagulation clinics in Brazil. A model containing the variables significantly associated with warfarin dose was estimated. Results: The mean age of patients was 64.1 ± 13.1 years, with 173 (54.9%) women. Age, use of amiodarone, genotype VKORC1 GA, genotype VKORC1 AA, genotypes CYP2C9*1/*2 or *1/*3 and genotypes CYP2C9*2/*2 or *2/*3 or *3/*3 were associated with a reduced warfarin dose. Conclusion: This study pointed out factors that could impact the management of oral anticoagulation.

Assessment of prescribing pattern and adverse drug reaction in patients receiving anticoagulant therapy: A prospective observational study

Introduction

Cardiovascular diseases (CVD) are the leading cause of death worldwide as well as a major blockade to sustainable human development. It is among the leading causes of morbidity and mortality. Anticoagulants are among the most essential life-saving drugs that are generally used in cardiology for the prevention and treatment of many CVD.

Objectives

To assess the prescribing pattern and adverse drug reaction (ADR) in patients receiving anticoagulant therapy for cardiac diseases.

Methodology

This was a Prospective Observational study conducted in the Department of Cardiology, SRM Medical College Hospital and Research Center, Kattankulathur including 88 patients for 6 months.

Results

Out of the 88 patients, the majority were males (73%) compared to females (27%), and the prevalence of CVD was found to be higher in patients above 40 years of age. Various categories of drugs prescribed to the patients were antiplatelets (14.88%), anticoagulants (8.79%), antianginal (13.82%), antihypertensives (15.7%), antihyperlipidemic (7.83%), thrombolytics (0.68%), Ionotropic agents (2.13%), antibiotics (5.31%), and other miscellaneous drugs (36.61%). The anticoagulant dosage regimens prescribed to the patients were categorized into monotherapy (9%), combinational therapy with antiplatelets (38%), and triple therapy (53%). The most commonly prescribed anticoagulant to the patients was Heparin (93.41%), followed by Warfarin (5.49%) and lastly Rivaroxaban (1.10%) respectively. From the details of the prescriptions analyzed, the average number of drugs per patient (prescription) was found to be 11.7.

Conclusion

Heparin was found to be the most commonly used anticoagulant, Combination therapy of antiplatelets and antihypertensives was observed in most of the prescriptions, which is more effective than a single therapy. Polypharmacy was encountered in the study with an average number of 11.7 drugs per prescription. Several anticoagulant-related drug interactions were identified and there were two adverse drug reactions with Heparin. The prescribing pattern can be improved by reducing the number of drugs prescribed.

Pharmacokinetic and Pharmacodynamic Interactions Between Henagliflozin, a Novel Selective SGLT-2 Inhibitor, and Warfarin in Healthy Chinese Subjects

PURPOSE

While controlling blood glucose, patients with diabetes and abnormal coagulation should be treated with positive anticoagulation because the hypercoagulable state of their blood is the primary cause of macroangiopathy. The goal of this study was to evaluate the pharmacokinetic and pharmacodynamic (PK/PD) interactions between henagliflozin, a novel selective sodium-glucose cotransporter 2 inhibitor, and warfarin in healthy subjects.

METHODS

This single-center, open-label, single-arm clinical study was conducted in 16 healthy male Chinese subjects. According to the study protocol, the PK properties of henagliflozin 10 mg/d and warfarin 5 mg/d were collected and tabulated in accordance with sampling time. All study drugs were given with once-daily administration. Subjects were monitored for adverse reactions and their severity, outcomes, and relationship to study drug. This influences of warfarin on the PK properties of henagliflozin (Cmax,ss and AUCτ,ss), the effects of henagliflozin on the PK properties of warfarin (Cmax, AUC0-t, and AUC0-∞), and the influences of henagliflozin on the PD properties of warfarin (PTmax, PTAUC, INRmax, and INRAUC) were evaluated.

FINDINGS

The geometric mean ratios (GMRs; 90% CIs) of henagliflozin Cmax,ss and AUCτ,ss were 101.75% (96.11%-107.72%) and 102.21% (100.04%-104.42%), respectively. The GMRs (90% CIs) of S- and R-warfarin Cmax, AUC0-t, and AUC0-∞ were as follows: Cmax, 114.31% (106.30%-122.91%) and 115.09% (109.46%-121.01%), respectively; AUC0-t, 120.15% (116.71%-123.69%) and 119.01% (116.32%-121.76%); and AUC0-∞, 120.81% (117.17%-124.58%) and 121.94% (118.90%-125.05%). The GMRs (90% CIs) of warfarin PTmax and PTAUC were 92.73% (91.25%-94.22%) and 97.42% (96.61%-98.24%). The GMRs (90% CIs) of warfarin INRmax and INRAUC were 92.66% (91.17%-94.17%) and 97.36% (96.52%-98.21%). A total of 32 cases of mild adverse events were reported, and were recovered/resolved. There were no serious adverse events reported.

IMPLICATIONS

No significant clinically relevant effects on the PK/PD properties of henagliflozin or warfarin were found with coadministration of the two drugs in these healthy male Chinese subjects. Based on these findings, it is expected that henagliflozin and warfarin can be used in combination without dose adjustment. Chinadrugtrials.org.cn identifier: CTR20190240.