American Society of Hematology 2018 guidelines for management of venous thromboembolism: optimal management of anticoagulation therapy

Anticoagulant Therapy in Patients Undergoing Acute Pulmonary Embolism Interventions

Catheter-based interventions and surgical embolectomy represent alternatives to systemic fibrinolysis for patients with high-risk pulmonary embolism (PE) or those with intermediate-high-risk PE who deteriorate hemodynamically. They are indicated when systemic fibrinolysis is contraindicated or ineffective, or if obstructive shock is imminent. Extracorporeal membrane oxygenation can be added to reperfusion therapies or used alone for severe right ventricular dysfunction and cardiogenic shock. These advanced therapies complement but do not replace anticoagulation, which remains the cornerstone in PE management. This review summarizes the evidence and shares practical recommendations for the use of anticoagulant therapy before, during, and after acute PE interventions.

Modelling the effects of 4-factor prothrombin complex concentrate for the management of factor Xa-associated bleeding

The management of factor Xa (FXa) inhibitor-associated bleeding remains a clinical challenge. Massive bleeding is often associated with complex coagulopathy and, thus, the sole reversal of FXa inhibitors might not be sufficient to restore hemostasis, requiring instead a multimodal approach. Four-factor prothrombin complex concentrate (4F-PCC) is widely recognized as a viable treatment option for FXa inhibitor-associated bleeding. Here, we applied computational models to explore the effect 4F-PCC has on the coagulation cascade and restoration of thrombin generation in a system that simulates a patient that has received a FXa inhibitor. The coagulation model is largely based on a previously developed model with modifications incorporated from various other published sources. The model was calibrated and validated using data from a phase 3 clinical trial of vitamin K antagonist reversal with 4F-PCC. Using the parameters and initial conditions determined during the calibration and validation process, the prothrombin time (PT) test simulations predicted a PT of 11.4 seconds. The model successfully simulated the effects of rivaroxaban and apixaban on total thrombin concentration and showed that 4F-PCC increased thrombin generation in the presence of rivaroxaban or apixaban.

Rate and predictors of thromboprophylaxis in internal medicine wards: Results from the AURELIO study

BACKGROUND

Randomized controlled trials suggest that prophylactic doses of anticoagulants effectively prevent venous thromboembolism (VTE) in hospitalized medical patients with high thromboembolic risk. However, no prospective studies exist regarding the real-world prevalence of prophylactic anticoagulant use. This prospective study aimed to determine the rate and predictors of thromboprophylaxis in an unselected population of patients hospitalized in medical departments.

METHODS

We conducted a multicenter prospective observational study (AURELIO - rAte of venous thrombosis in acutely iLl patIents hOspitalized) to assess the rate of deep vein thrombosis (DVT) in unselected acutely ill patients hospitalized in medical wards using compression ultrasound (CUS) at admission and discharge. Additionally, we evaluated the rate of pharmacological thromboprophylaxis administration in this population and analyzed the thrombotic risk by assessing RAMs (Risk Assessment Models) such as the IMPROVE-VTE and PADUA scores following the clinician's decision to administer thromboprophylaxis. Patients with IMPROVE-VTE scores ≥3 and/or PADUA scores ≥4 were classified as high thrombotic risk; those with IMPROVE-VTE scores <3 and/or PADUA scores <4 were classified as low risk.

RESULTS

We recruited 2371 patients (1233 males [52 %] and 1138 females [48 %]; mean age 72 ± 16 years). The median length of hospitalization was 13 ± 12 days. Overall, 442/2371 (18.6 %) patients received prophylactic parenteral anticoagulants (subcutaneous low weight molecular heparin or fondaparinux once daily) at admission. Assessing the thrombotic risk of the population recruited 1016 (42.9 %) patients were classified as high risk and 1354 (57.1 %) were low risk. Among high-risk patients, 339/1016 (33.4 %) received anticoagulant prophylaxis compared to 103/1354 (7.6 %) low-risk patients. During hospitalization, 9 patients developed DVT, comprising 7 asymptomatic and 2 symptomatic cases of proximal DVT. Of these, 3 patients were on anticoagulant prophylaxis, while 6 were not. Among the high-risk population, 7 out of 1016 patients (0.7 %) experienced proximal DVT during hospitalization, with 2 out of these 7 (28 %) receiving anticoagulant thromboprophylaxis. In the low-risk population, 2 out of 1354 patients (0.2 %) developed DVT, with 1 out of these 2 (50 %) receiving anticoagulant thromboprophylaxis. Age, heart or respiratory failure, pneumonia, active neoplasia, previous VTE, reduced mobility, and absence of kidney failure were more frequent in patients receiving prophylaxis. Multivariable logistic regression identified age (RR 1.010; CI 95 % 1002-1019; p = 0.015), heart/respiratory failure (RR 1.609; CI 95 % 1248-2075; p < 0.0001), active neoplasia (RR 2.041; CI 95 % 1222-2141; p < 0.0001), pneumonia (RR 1.618; CI 95 % 1557-2676; p < 0.0001), previous VTE (RR 1.954; CI 95 % 1222-3125; p < 0.0001), and reduced mobility (RR 4.674; CI 95 % 3700-5905; p < 0.0001) as independent predictors of thromboprophylaxis.

CONCLUSIONS

This study, conducted without pre-established thromboembolic risk scores, offers a comprehensive view of venous thromboembolism prophylaxis in medical patients with acute conditions hospitalized in internal medicine departments. It reveals that advanced age, heart or respiratory failure, active cancer, pneumonia, previous VTE, and reduced mobility are predictors that may influence the decision to administer thromboprophylaxis in these patients.

Rate of recurrence after discontinuing anticoagulation in patients with venous thromboembolism within 30 days after COVID-19 vaccine

This study generated evidence to guide anticoagulation in patients with VTE after vaccination for COVID-19. We provided data on the low recurrence rate after cessation of anticoagulant therapy and the findings for this study offer timely insights into the management of a potentially vaccine-related adverse event.

Guidelines on deep vein thrombosis of the Brazilian Society of Angiology and Vascular Surgery

Deep vein thrombosis is one of the main causes of inpatient and outpatient morbidity, both in medical and surgical patients, significantly impacting mortality statistics and requiring prompt diagnosis so that treatment can be initiated immediately. This document was prepared and reviewed by 11 specialists certified by the Brazilian Society of Angiology and Vascular Surgery, who searched the main databases for the best evidence on the diagnostic (physical examination, imaging) and therapeutic approaches (heparin, coumarins, direct oral anticoagulants, fibrinolytics) to the disease.

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.

Assessment of Temporary Warfarin Reversal in Patients With Left Ventricular Assist Devices: the KVAD Study

BACKGROUND

Patients with left ventricular assist devices (LVADs) require interruption of warfarin for invasive procedures, but parenteral bridging is associated with many complications. Four-factor prothrombin complex concentrate (4F-PCC) can temporarily restore hemostasis in patients undergoing anticoagulation with warfarin.

OBJECTIVES

This pilot study evaluated the strategy of using variable-dose 4F-PCC to immediately and temporarily reverse warfarin before invasive procedures without holding warfarin in patients with LVADs. The duration of effect of 4F-PCC on factor levels and time to reestablish therapeutic anticoagulation post procedure were assessed.

METHODS

Adult patients with LVADs and planned invasive procedures were enrolled from a single center. Warfarin was continued uninterrupted. The 4F-PCC dose administered immediately pre-procedure was based on study protocol. International normalized ratio (INR)- and vitamin K-dependent factor levels were collected before and during the 48 hours after 4F-PCC administration. The use of parenteral bridging, International Society for Thrombosis and Haemostasis major and clinically relevant nonmajor bleeding (CRNMB) and thromboembolic events at 7 and 30 days were collected.

RESULTS

In 21 episodes of 4F-PCC reversal, median baseline INR was 2.7 (IQR 2.2-3.2). The median dosage of 4F-PCC administered was 1794 units (IQR 1536-2130). At 24 and 48 hours post 4F-PCC administration, median INRs were 1.8 (IQR 1.7-2.0) and 2.0 (IQR 1.9-2.4). Two patients required postoperative bridging. One patient experienced major bleeding within 72 hours, and 2 experienced CRNMB within 30 days. There were no thromboembolic events. Baseline and post 4F-PCC vitamin K-dependent factor levels corresponded with changes in INR values. The median time to achieve therapeutic INR post-procedure was 2.5 days (IQR, 1-4).

CONCLUSION

Administration of 4F-PCC for temporary reversal of warfarin for invasive procedures in patients with LVADs allowed for continued warfarin dosing with minimal use of post-intervention bridging, limited bleeding and no thromboembolic events.

Advances in the medical treatment and diagnosis of intracranial hemorrhage associated with oral anticoagulation

INTRODUCTION

With the increasing prevalence of atrial fibrillation (AF), it entails expanding oral anticoagulants (OACs) use, carrying a higher risk of associated hemorrhagic events, including intracranial hemorrhage (ICH). Despite advances in OACs development with a better safety profile and reversal agent for these anticoagulants, there is still no consensus on the optimal management of patients with OACs-associated ICH.

AREAS COVERED

In this review, the authors have carried out an exhaustive search on the advances in recent years. The authors provide an update on the management of ICH in anticoagulated patients, as well as an update on the latest evidence on anticoagulation resumption, recent therapeutic strategies, and investigational drugs that could play a role in the future.

EXPERT OPINION

Following an ICH event in an anticoagulated patient, a comprehensive clinical evaluation is imperative. Anticoagulation should be promptly withdrawn and reversed. Once the patient is stabilized, a reintroduction of anticoagulation should be considered, typically within a timeframe of 4-8 weeks, if feasible. If re-anticoagulation is not possible, alternative options such as Left Atrial Appendage Occlusion are available.

Anticoagulation and compression therapy for proximal acute deep vein thrombosis

The treatment of proximal deep vein thrombosis (DVT) of the lower limbs includes an initial management phase, covering the first 1 to 3 weeks, a primary treatment phase, lasting a minimum of 3 months, and a secondary treatment phase for those patients requiring continuing anticoagulation beyond the first 3 to 6 months. During the initial phase most patients with DVT can be managed as outpatients. Exclusion criteria for home treatment include high risk of bleeding, limb threatening DVT or other conditions requiring hospitalisation. Anticoagulant drugs represent the mainstay of treatment and include parenteral drugs such as unfractionated heparin or low molecular weight heparin, and oral drugs such as the vitamin K antagonists and the direct oral anticoagulants (DOACs). DOACs are currently recommended as the first line of treatment for proximal DVT of the lower limbs, with no preference for one DOAC over another. Factors to consider when choosing the anticoagulant strategy include, among others, renal and liver function, underlying diseases such as cancer or the antiphospholipid syndrome, and patient preferences. Indefinite duration of anticoagulation beyond the first 3 to 6 months is recommended for patients with unprovoked DVT and patients with permanent, chronic risk factors. Two DOACs, namely apixaban and rivaroxaban, can be administered at low doses for the secondary prevention of DVT. Elastic compression stockings (ECS) have been used for decades in patients with proximal DVT with the aim of counteracting the venous hypertension generated by the vascular disorder and reducing leg edema and to prevent the post-thrombotic syndrome.

Unresolved questions on venous thromboembolic disease. Venous thromboembolism (VTE) management in obese patients. Consensus statement of the French Society of Vascular Medicine (SFMV)

Obesity is an alarming worldwide public health issue and is defined as a body mass index (BMI) of 30kg/m2 or more. It is considered as a risk factor for first thrombotic event and is associated with a significant risk of recurrence. Consequently, obese patients are often treated by anticoagulant therapy but data from randomised control trial are scarce. We will review in this narrative review the state of the art of the prescription of anticoagulant for the prevention and treatment of venous thromboembolism (VTE) in obese patients.

Finding individualised treatment in obese needing enoxaparin (FIT ONE): a multicentre study of therapeutic enoxaparin and the role of anti-factor Xa monitoring

Enoxaparin is dosed according to actual body weight in treatment of arterial and venous thrombosis. Due to its hydrophilic nature, it distributes according to lean body mass which may be problematic when dosing obese patients as this may increase the risk of bleeding events in this population. The aim was to evaluate current therapeutic enoxaparin dosing strategies, including Antifactor Xa (AFXa) level monitoring, in obese patients and to identify factors that contribute to treatment failure and excess anticoagulation. A retrospective cohort study was conducted reviewing patients administered therapeutic enoxaparin between May 2020 and April 2021. Data were collected on patient characteristics, enoxaparin therapy, AFXa monitoring, and outcomes. Regression models were constructed to assess variables of interest to estimate any association with AFXa levels. In total 762 patients were included in the analysis. The mean initial weight-based dose was 0.95 mg/kg twice daily (SD: ± 0.12, IQR 0.92-1.01) and 1.04 mg/kg once daily (SD: ± 0.26, IQR 0.93-1.12) and 14.4% of patients had AFXa monitoring. Treatment failure was experienced by 2.2%, 5% experienced bleeding. There was no association between the mean actual milligram per kilogram weight-based twice daily doses and subtherapeutic, therapeutic and supratherapeutic AFXa levels (P = 0.135). Obesity was not included in the final regression models due to lack of significance. At a mean therapeutic enoxaparin dose of 0.95 mg/kg twice daily and 1.04 mg/kg once daily no excess in treatment failure or bleeding events were observed in obese patients compared to the product information. Obesity was not an independent variable that affected the achievement of target AFXa levels.

Atrial fibrillation management in older hospitalized patients: Evidence of a poor oral anticoagulants prescriptive attitude from the Italian REPOSI registry

Atrial fibrillation (AF) prevalence increases in older patients which also show a high thromboembolic risk. Oral anticoagulants (OACs) are recommended to prevent cardioembolic events and direct oral anticoagulants (DOACs) improved anti-thrombotic treatment. However, the benefits/risks of anticoagulant in older patients still need to be completely defined. This retrospective observational study aimed to describe the treatment with OACs in older AF hospitalized patients, and to identify factors influencing OAC therapy or discontinuation using the REgistro Politerapie SIMI. Univariate and multivariate logistic regression models were applied to identify predictors of OACs treatment and discontinuation. Cox proportional hazards models were performed to evaluate one-year mortality by treatment groups. AF patients were 1,128(26.5 %) at discharge and 1,098(97.3 %) required OAC treatment; about half of them (N = 528;48.1 %) were no-OACs users; 236(21.5 %) and 334(30.4 %) used DOACs and VKA, respectively. Increasing DOACs use was observed during the study period. Predictors of OACs treatment were: BMI (OR:1.04; 95 %CI:1.01-1.07), Barthel index (OR:1.01; 95 %CI:1.01-1.02), medications number (OR:1.07; 95 %CI:1.01-1.13). Conversely, a lower probability was found in patients with a high CIR.S (OR:0.59; 95 %CI:0.36-0.97) and neoplasm (OR:0.57; 95 %CI:0.37-0.88). Hospital stay (OR:1.02; 95 %CI:1.01-1.05), neoplasm (OR:2.25; 95 %CI:1.07-4.70) and INR (OR:1.21; 95 %CI:1.05-1.40) increased OACs discontinuation. A lower discontinuation was observed in dyslipidemic patients (OR:0.18; 95 %CI:0.04-0.82) and heart failure (OR:0.38; 95 %CI:0.21-0.70). Among AF patients, 157(14.3 %) died during the follow-up year. Age (HR = 1.05; 95 %CI = 1.03-1.08) and CIR.S (HR = 2.54; 95 %CI = 1.53-4.21) were associated with a greater mortality risk. In conclusion, critical issues related to the underuse and discontinuation of OACs therapy in hospitalized older patients were highlighted.

Anticoagulation in Chronic Kidney Disease

The nuanced landscape of anticoagulation therapy in patients with chronic kidney disease (CKD) presents a formidable challenge, intricately balancing the dual hazards of hemorrhage and thrombosis. These patients find themselves in a precarious position, teetering on the edge of these risks due to compromised platelet functionality and systemic disturbances within their coagulation frameworks. The management of such patients necessitates a meticulous approach to dosing adjustments and vigilant monitoring to navigate the perilous waters of anticoagulant therapy. This is especially critical considering the altered pharmacokinetics in CKD, where the clearance of drugs is significantly impeded, heightening the risk of accumulation and adverse effects. In the evolving narrative of anticoagulation therapy, the introduction of direct oral anticoagulants (DOACs) has heralded a new era, offering a glimmer of hope for those navigating the complexities of CKD. These agents, with their promise of easier management and a reduced need for monitoring, have begun to reshape the contours of care, particularly for patients not yet on dialysis. However, this is not without its caveats. The application of DOACs in the context of advanced CKD remains a largely uncharted territory, necessitating a cautious exploration to unearth their true potential and limitations. Moreover, the advent of innovative strategies such as left atrial appendage occlusion (LAAO) underscores the dynamic nature of anticoagulation therapy, potentially offering a tailored solution for those at the intersection of CKD and elevated stroke risk. Yet the journey toward integrating such advancements into standard practice is laden with unanswered questions, demanding rigorous investigation to illuminate their efficacy and safety across the spectrum of kidney disease. In summary, the management of anticoagulation in CKD is a delicate dance, requiring a harmonious blend of precision, caution, and innovation. As we venture further into this complex domain, we must build upon our current understanding, embracing both emerging therapies and the need for ongoing research. Only then can we hope to offer our patients a path that navigates the narrow strait between bleeding and clotting, toward safer and more effective care.

Temporal Changes in Long-Term Outcomes of Venous Thromboembolism From the Warfarin Era to the Direct Oral Anticoagulant Era

BACKGROUND

There have been limited data on the changes in clinical outcomes after the introduction of direct oral anticoagulants (DOACs) for venous thromboembolism (VTE) in real clinical practice. We evaluated the changes in management strategies and long-term outcomes from the warfarin era to the DOAC era.

METHODS AND RESULTS

We compared the 2 series of multicenter COMMAND VTE (Contemporary Management and Outcomes in Patients With Venous Thromboembolism) registries in Japan enrolling consecutive patients with acute symptomatic VTE: Registry 1: 3027 patients in the warfarin era (2010-2014) and Registry 2: 5197 patients in the DOAC era (2015-2020). The prevalence of DOAC use increased more in Registry 2 than in the Registry 1 (Registry 1: 2.6% versus Registry 2: 79%, P<0.001). The cumulative 5-year incidence of recurrent VTE was significantly lower in Registry 2 than in Registry 1 (10.5% versus 9.5%, P=0.02), and the risk reduction of recurrent VTE in Registry 2 remained significant even after adjusting the confounders (hazard ratio [HR], 0.78 [95% CI, 0.65-0.93]; P=0.005). The cumulative 5-year incidence of major bleeding was not significantly different between the 2 registries (12.1% versus 13.7%, P=0.26), and the risk of major bleeding between the 2 registries was not significantly different even after adjusting the confounders (HR, 1.04 [95% CI, 0.89-1.21]; P=0.63).

CONCLUSIONS

Along with the shift from warfarin to DOACs, there was a lower risk of recurrent VTE in the DOAC era than in the warfarin era, whereas there was no apparent change in the risk of major bleeding, which might still be an unmet need even in the DOAC era.

Co-administration of Four-Factor Prothrombin Complex Concentrate With Andexanet alfa for Reversal of Nontraumatic Intracranial Hemorrhage

Objective: Andexanet alfa is approved for the reversal of life-threatening or uncontrolled bleeding due to factor-Xa inhibitors. Data are limited on outcomes for patients who receive both andexanet alfa and 4-factor prothrombin complex concentrate (4F-PCC). The aim of this case series is to evaluate the safety and efficacy outcomes in patients receiving the two agents in combination. Methods: Electronic medical records of patients who received both 4F-PCC and andexanet alfa for nontraumatic intracranial hemorrhage from January 2019 to March 2022 were retrospectively reviewed. Hemostatic efficacy and complications related to concurrent use of 4F-PCC with andexanet alfa were documented. Results: Nine patients received 4F-PCC and andexanet alfa for reversal of factor Xa inhibitor-associated intracranial bleeding, eight of whom required reversal of apixaban. Of these nine patients, five patients died within 28 days for a 56% incidence of mortality. The average time from 4F-PCC administration to andexanet alfa administration was 3 hours and 9 minutes. Most doses of andexanet alfa were given for concern for bleed expansion after 4F-PCC administration. Hemostatic efficacy based on stability of repeat computed tomography scans post-administration of both agents was found in six patients (66.67%), with a 55.56% n incidence of thromboembolism, including two pulmonary embolisms, two deep vein thromboses, and one renal artery thrombosis. Conclusion: Risks and benefits should be weighed to determine if there is benefit to adding andexanet alfa to 4F-PCC in patients with incomplete hemostasis and life-threatening hemorrhage. The combination of andexanet alfa and 4F-PCC may increase the risk of thrombotic complications without improving mortality.

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.

Apixaban versus low molecular weight heparin in patients with cancer-associated venous thromboembolism: a systematic review and meta-analysis

Background

The optimal treatment regimen for patients with cancer-associated venous thromboembolism (CA-VTE) remains unclear. Therefore, the authors sought to compare the outcomes of (VKAs) versus direct apixaban and low molecular weight heparin (LMWH) in patients with CA-VTE.

Methods

MEDLINE, Embase, and Cochrane Central databases were searched for randomized controlled trials (RCTs) and observational studies comparing the efficacy and safety of apixaban and LMWH in patients with CA-VTE. Major bleeding, clinically relevant non-major bleeding (CRNMB), recurrence of pulmonary embolism (PE), deep venous thrombosis (DVT) and bleeding-related mortality were among outcomes of interest. Mantel-Haenszel weighted random-effects model was used to calculate relative risks (RRs) with 95% CIs.

Results

The analysis included 12 011 patients from 3 RCTs and 2 observational studies. Compared to LMWH, apixaban significantly decreased the risk of major bleeding [RR 0.67 (95% CI 0.54, 0.83); P=0.0003, I2=0%] without significantly changing the risk of clinically relevant non-major bleeding [RR 0.96 (95% CI 0.64, 0.1.45); P=0.85, I2=57%]. Patients on apixaban had a noticeably reduced the risk of recurrence of PE than those taking LMWH, according to a meta-analysis [RR 0.56 (95% CI 0.32, 0.99); P=0.05, I2=0%]. There was no discernible difference between apixaban and LMWH in bleeding-related mortality events [RR 0.20 (95% CI 0.01, 4.18); P=0.30, I2=NA%], and recurrence of DVT [RR 0.60 (95% CI 0.22, 1.59); P=0.23, I2=32%].

Conclusion

Due to its lower risk of severe bleeding and reduced PE recurrence, apixaban may be a preferable treatment option for CA-VTE, but additional research is required to validate these conclusions and evaluate its long-term efficacy and safety.

Long-Term Safety of a Four-Factor Prothrombin Complex Concentrate (Kcentra®/Beriplex® P/N): An Updated Pharmacovigilance Review

INTRODUCTION

 Four-factor prothrombin complex concentrate (4F-PCC) is recommended for vitamin K antagonist reversal in patients with major bleeding or in need of surgery. The most important risk associated with the use of 4F-PCC is the occurrence of thromboembolic events (TEEs). In this review, we aim to evaluate the safety profile of a 4F-PCC (Kcentra®/Beriplex® P/N; CSL Behring, Marburg, Germany) by reviewing pharmacovigilance data.

METHODS

 A retrospective analysis of postmarketing pharmacovigilance data of Kcentra®/Beriplex® P/N from February 1996 to April 2022 was performed and complemented by a review of clinical studies published between January 2012 and April 2022.

RESULTS

 A total of 2,321,443 standard infusions of Kcentra®/Beriplex® P/N were administered during the evaluation period. Adverse drug reactions (ADRs) were reported in 614 cases (∼1 per 3,781 standard infusions) and 233 of these cases (37.9%) experienced suspected TEEs related to 4F-PCC (∼1 per 9,963 standard infusions); most of these cases had pre-existing or concomitant conditions likely to be significant risk factors for thrombosis. TEE rates were similar when 4F-PCC was used on-label or off-label for direct oral anticoagulant-associated bleeding. Thirty-six cases (5.9%) reported hypersensitivity type reactions (∼1 per 64,485 standard infusions). No confirmed case of viral transmission related to 4F-PCC use was reported. The published literature also revealed a favorable safety profile of 4F-PCC.

CONCLUSION

 Analysis of postmarketing pharmacovigilance safety reports demonstrated that treatment with 4F-PCC was associated with few ADRs and a low rate of TEEs across multiple indications and settings, thus confirming a positive safety profile of 4F-PCC.

Poor patients' knowledge about venous thromboembolism and its therapy is associated with increased risk of major bleeding and discontinuation of anticoagulation: A cohort study

It has been shown that patients' knowledge about venous thromboembolism (VTE) and its therapy is suboptimal, which might reduce compliance and worsen prognosis. We investigated whether low VTE patients' knowledge affects their clinical outcomes during long-term follow-up. We evaluated 151 consecutive patients (51.8 ± 15.7 years) after unprovoked VTE, who were recruited from the outpatient clinic (Krakow, Poland). All patients received anticoagulant treatment, mostly with direct oral anticoagulants (n = 113, 74.8%). The modified Jessa Atrial fibrillation Knowledge Questionnaire (JAKQ-VTE; 16 questions) was used to assess the knowledge of VTE and anticoagulant therapy. During a median follow-up of 58.0 months, VTE recurrence, major bleeding, and anticoagulation withdrawal were recorded. The median percentage of correct responses was 62.5% (12.5-100%) and was inversely correlated with age (P < .01). Diabetic patients and those with positive family history of VTE had lower overall scoring compared to the remainder (both P < .05). Major bleeding (n = 10, 6.6%) and anticoagulation withdrawal (n = 28, 18.5%), but not VTE recurrence (n = 12, 7.9%), were associated with lower overall scoring compared to the remainder (48.8% ± 12.5% vs 63.8% ± 16.3%, P = .003 and 55.3% ± 14.7% vs 64.4% ± 16.3%, P = .040, respectively). Major bleeding was independently associated with the female sex (hazard ratio [HR] 6.18; 95% confidence interval [CI] 1.15-33.19, P = .034), younger age (HR per 10 years 0.55; 95% CI 0.34-0.90, P = .016), OAC therapy discontinuation (HR 6.69; 95% CI 1.62-27.70), and lower overall scoring of JAKQ-VTE (HR 0.60 per 10 percentage points; 95% CI 0.40-0.92, P = .019). Insufficient knowledge about VTE and anticoagulant treatment predisposes to a higher risk of major bleeding and therapy discontinuation, but not VTE recurrence in unprovoked VTE patients during long-term follow-up.

Incidence, Predictors, and Outcomes of Venous and Arterial Thrombosis in COVID-19: A Nationwide Inpatient Analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) is known to increase the risk of venous thromboembolism (VTE) and arterial thromboembolism (ATE). However, the incidence, predictors, and outcomes of clinical thrombosis for inpatients with COVID-19 are not well known. This study aimed to enhance our understanding of clinical thrombosis in COVID-19, its associated factors, and mortality outcomes.

METHOD

Hospitalised adult (≥18 years of age) patients with COVID-19 in 2020 were retrospectively identified from the US National Inpatient Sample database. Clinical characteristics, incident VTE, ATE, and in-hospital mortality outcomes were recorded. Multivariable logistic regression was performed to identify clinical factors associated with thrombosis and in-hospital mortality in COVID-19 inpatients.

RESULTS

A total of 1,583,135 adult patients with COVID-19 in the year 2020 were identified from the National Inpatient Sample database; patients with thrombosis were 41% females with a mean age of 65.4 (65.1-65.6) years. The incidence of thrombosis was 6.1% (97,185), including VTE at 4.8% (76,125), ATE at 3.0% (47,790), and the in-hospital mortality rate was 13.4% (212,785). Patients with thrombosis were more likely to have respiratory symptoms of COVID-19 (76.7% vs 75%, p<0.001) compared with patients without thrombosis. The main factors associated with overall thrombosis, VTE, and ATE were paralysis, ventilation, solid tumours without metastasis, metastatic cancer, and acute liver failure. Although all thrombosis categories were associated with higher in-hospital mortality for COVID-19 inpatients in univariable analyses (p<0.001), they were not in multivariable analyses-thrombosis (odds ratio [OR] 1.24; 95% confidence interval [CI] 0.90-1.70; p=0.19), VTE (OR 0.70; 95% CI 0.52-1.00; p=0.05), and ATE (OR 1.07; 95% CI 0.92-1.25; p=0.36).

CONCLUSIONS

The association of COVID-19 with thrombosis and VTE increases with increasing severity of the COVID-19 disease. Risk stratification of thrombosis is crucial in COVID-19 patients to determine the necessity of thromboprophylaxis.

Anticoagulation reversal (vitamin K, prothrombin complex concentrates, idarucizumab, andexanet-α, protamine)

Bleeding events are common in patients prescribed anticoagulants and can have devastating consequences. Several specific and nonspecific agents have been developed to reverse the effects of anticoagulant drugs or toxins. Vitamin K, as the oldest of these antidotes, specifically counteracts the effects of pharmaceuticals and rodenticides designed to deplete stores of vitamin K-dependent factors. In cases of life-threatening bleeding, the addition of prothrombin complex concentrates (PCCs) allows for the immediate replacement of coagulation factors. While the use of PCCs has been extended to the non-specific reversal of the effects of newer direct oral anticoagulants, the specific agents idarucizumab, targeting dabigatran and andexanet-α, binding factor Xa inhibitors, have recently been developed and are being preferentially recommended by most guidelines. However, despite having rapid effects on correcting coagulopathy, there is to date a lack of robust evidence establishing the clear superiority of direct oral anticoagulant-specific reversal agents over PCCs in terms of haemostatic efficacy, safety or mortality. For andexanet-α, a potential signal of increased thromboembolic risks, comparatively high costs and low availability might also limit its use, even though emerging evidence appears to bolster its role in intracranial haemorrhage. Protamine is the specific agent for the reversal of unfractionated heparin anticoagulation used mainly in cardiovascular surgery. It is much less effective for low molecular weight heparin fragments and is usually reserved for cases with life-threatening bleeding.

Comparison of anticoagulation control and outcomes between usual medical care and pharmacist-led anticoagulation service in ambulatory patients taking warfarin at tertiary hospital in Ethiopia: a quasi-experimental study

BACKGROUND

We aimed to compare anticoagulation control and outcomes between usual medical care (UMC) and pharmacist-led anticoagulation services (PLAS) in patients receiving warfarin at the Tikur Anbessa Specialized Hospital (TASH), Addis Ababa, Ethiopia.

METHODS

A quasi-experimental study was conducted, including 350 (66.7%) and 175 (33.3%) patients from the UMC and PLAS groups, respectively, from 525 patients. The time in therapeutic range (TTR) was determined using the Rosendaal method, with a TTR ≥ 65% set as the cut-off for optimal anticoagulation. The two-sample Wilcoxon rank-sum (Mann-Whitney U) test was used to compare continuous variables between groups. Categorical variables were compared between groups using Pearson's chi-square test or Fisher's exact test. Logistic regression and negative binomial regression analyses were conducted to identify the factors associated with suboptimal TTR and secondary outcomes, respectively, at the p values < 0.05, and 95% confidence interval (CI).

RESULTS

Compared with the UMC group, the patients in the PLAC group showed a significantly higher median (IQR) TTR [60.89% (43.5-74.69%) vs. 53.65% (33.92-69.14%), p < 0.001]. A significantly higher optimal TTR (≥ 65%) was achieved in the PLAC group (41.7% vs. 31.7%) than in the UMC group (p = 0.002). The odds of having a poor TTR were reduced by 43% (AOR = 0.57, 95% CI = 0.36-0.88, p = 0.01) among patients in the PLAC group compared to those in the UMC group. There were no statistically significant differences in the secondary outcomes between the groups, except for all-cause emergency visits (p = 0.003). The incidence of bleeding events decreased by 3% (IRR = 0.97, 95% CI = 0.96-0.99, p < 0.001) for every increase in INR monitoring frequency. The incidence of thromboembolic events increased by a factor of 15.13 (IRR = 15.13, 95% CI = 1.47-155.52, p = 0.02) among patients with a high-risk CHA2DS2-VASc score compared with those with a moderate score.

CONCLUSION

Patients in the PLAC group had a significantly higher median TTR than those in the UMC group did. There were no statistically significant differences in the secondary outcomes between the groups, except for fewer all-cause emergency department visits in the PLAC group.

Hemostasis Testing in the Emergency Department: A Narrative Review

Routine laboratory screening is typically performed at initial evaluation of the vast majority of presentations to the emergency department (ED). These laboratory results are crucial to the diagnostic process, as they may influence up to 70% of clinical decisions. However, despite the usefulness of biological assessments, many tests performed are inappropriate or of doubtful clinical relevance. This overutilization rate of laboratory testing in hospitals, which represents a significant medical-economic burden, ranges from 20 to 67%, with coagulation tests at the top of the list. While reviews frequently focus on nonintensive care units, there are few published assessments of emergency-specific interventions or guidelines/guidance to date. The aim of this review is to highlight current recommendations for hemostasis evaluation in the emergency setting with a specific analysis of common situations leading to ED admissions, such as suspected venous thrombosis or severe bleeding. We revisit the evidence related to the assessment of patient's hemostatic capacity based on comprehensive history taking and physical examination as well as best practice recommendations for blood sample collection to ensure the reliability of results. This review also includes an examination of various currently available point of care tests and a comprehensive discussion on indications, limitations, and interpretation of these tests.

DOAC-Remove to counteract the interference of anti-Xa oral anticoagulants on the monitoring of heparin

INTRODUCTION

The monitoring of unfractionated heparin (UFH) by anti-factor Xa activity (AXA) is commonly used to ensure effective anticoagulation and prevent bleeding risk. However, in patients previously treated with an anti-Xa direct oral anticoagulant (DOAC) switching to UFH therapy, there is a risk of interference that may lead to inappropriate anticoagulation. The first objective of this study was to validate DOAC-Remove to remove DOAC for measuring UFH specific AXA. The second objective was to assess the length of DOAC interference on UFH monitoring and to identify potential predictive factors.

MATERIALS AND METHODS

This monocentric retrospective study included all patients admitted from April 2019 to April 2021 previously treated with anti-Xa DOAC, and for whom an interference on UFH monitoring was suspected. Interference was defined as a difference in the AXA measured before and after using DOAC-Remove >2.8-fold standard deviation of the method.

RESULTS

Removal with DOAC-Remove was specific of DOAC (apixaban n = 42, rivaroxaban n = 41, UFH n = 20) and sufficient to avoid interference on UFH AXA measurement. The exact interference length was 6.0 days [IQR 3.0-11.0] for apixaban (n = 26) and 4.5 days [IQR 2.0-5.8] for rivaroxaban (n = 20). Among the 89 patients sorted based on an interference length ≤ or >3 days, 74 (83.1%) presented an interference greater than 3 days. Correlations were observed with age for apixaban and creatinine for rivaroxaban.

CONCLUSIONS

Our results suggest that DOAC-Remove could be of high interest in patients receiving UFH previously treated with an anti-Xa DOAC even if DOAC was stopped for more than 3 days.

Andexanet Alfa versus Four-Factor Prothrombin Complex Concentrate for the Reversal of Factor Xa (FXa) Inhibitor-Associated Intracranial Hemorrhage: A Systematic Review of Retrospective Studies

Background/Objectives: There are limited data on the risks and benefits of using Andexanet alfa (AA) compared with four-factor prothrombin complex concentrate (4F-PCC) for the reversal of factor Xa inhibitor-associated intracranial hemorrhage (ICH). Our aim was to describe a compilation of the information available in the literature to date. Methods: PubMed, Embase, Web of Science (Clarivate Analytics) and the Cochrane Central Register of Controlled Trials were searched until December 2023. Following the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)" guidelines, our systematic literature review included studies that were retrospective in design and evaluated both drugs to control bleeding and complications (death and thromboembolic events). Two researchers re-examined the studies for relevance, extracted the data and assessed the risk of bias. No meta-analyses were performed for the results. Results: In this limited patient sample, we found no differences between published articles in terms of neuroimaging stability or thrombotic events. However, some studies show significant differences in mortality, suggesting that one of the AAs may be superior to 4F-PCC. Conclusions: Our qualitative analysis shows that AA has a better efficacy profile compared with 4F-PCC. However, further studies monitoring these patients and a multicenter collaborative network dedicated to this topic are needed.

Idarucizumab in dabigatran-treated patients with acute stroke: a review and clinical update

Idarucizumab is an antibody fragment specific for the immediate reversal of dabigatran anticoagulation effects. The use of idarucizumab is approved for dabigatran-treated patients suffering from life-threatening or uncontrolled bleeding and those in need of urgent surgery or invasive procedures. Data from randomized controlled clinical trials and real-world experience provide reassuring evidence about the efficacy and safety of idarucizmab use in patients with acute stroke. In this narrative review, we summarize the available real-world evidence and discuss the relevance and importance of idarucizumab treatment in acute stroke patients in everyday clinical practice. In addition, we also discuss special issues like prothrombin complex concentrate application as an alternative to idarucizumab, its application before endovascular therapy, sensitivity of thrombi to lysis, and necessary laboratory examinations.

Coordination of oral anticoagulant care at hospital discharge (COACHeD): pilot randomised controlled trial

OBJECTIVES

To evaluate whether a focused, expert medication management intervention is feasible and potentially effective in preventing anticoagulation-related adverse events for patients transitioning from hospital to home.

DESIGN

Randomised, parallel design.

SETTING

Medical wards at six hospital sites in southern Ontario, Canada.

PARTICIPANTS

Adults 18 years of age or older being discharged to home on an oral anticoagulant (OAC) to be taken for at least 4 weeks.

INTERVENTIONS

Clinical pharmacologist-led intervention, including a detailed discharge medication management plan, a circle of care handover and early postdischarge virtual check-up visits to 1 month with 3-month follow-up. The control group received the usual care.

OUTCOMES MEASURES

Primary outcomes were study feasibility outcomes (recruitment, retention and cost per patient). Secondary outcomes included adverse anticoagulant safety events composite, quality of transitional care, quality of life, anticoagulant knowledge, satisfaction with care, problems with medications and health resource utilisation.

RESULTS

Extensive periods of restriction of recruitment plus difficulties accessing patients at the time of discharge negatively impacted feasibility, especially cost per patient recruited. Of 845 patients screened, 167 were eligible and 56 were randomised. The mean age (±SD) was 71.2±12.5 years, 42.9% females, with two lost to follow-up. Intervention patients were more likely to rate their ability to manage their OAC as improved (17/27 (63.0%) vs 7/22 (31.8%), OR 3.6 (95% CI 1.1 to 12.0)) and their continuity of care as improved (21/27 (77.8%) vs 2/22 (9.1%), OR 35.0 (95% CI 6.3 to 194.2)). Fewer intervention patients were taking one or more inappropriate medications (7 (22.5%) vs 15 (60%), OR 0.19 (95% CI 0.06 to 0.62)).

CONCLUSION

This pilot randomised controlled trial suggests that a transitional care intervention at hospital discharge for older adults taking OACs was well received and potentially effective for some surrogate outcomes, but overly costly to proceed to a definitive large trial.

TRIAL REGISTRATION NUMBER

NCT02777047.

Outcomes of Warfarin Home INR Monitoring vs Office-Based Monitoring: a Retrospective Claims-Based Analysis

BACKGROUND

Home INR testing (patient self-testing) is feasible and effective for warfarin patients but little is known about real-world differences in outcomes for patients using PST versus laboratory-based INR monitoring.

OBJECTIVE

To compare the safety/efficacy of patient self-testing of real-world warfarin therapy versus office/lab-based monitoring of therapy.

DESIGN/SETTING/PARTICIPANTS/EXPOSURE

A retrospective claims-based analysis of warfarin patients enrolled in the MarketScan® Commercial Claims and Encounters and Medicare databases between January 1, 2013, and March 30, 2020. Stratification was based on INR testing method: patient self-testing versus testing at physicians' offices/local laboratory. The probability of adverse events in each cohort was determined after adjusting for demographic and baseline clinical characteristics using a repeated measures analysis.

MAIN MEASURES

Rates of all adverse events: deep venous thrombosis, pulmonary embolism, bleeding, and stroke. A secondary outcome of interest was emergency department visits.

KEY RESULTS

A total of 37,837 patients were included in the analysis: 1592 patients in the patient self-testing group and 36,245 in the office-based therapy group. After adjusting for demographic and baseline clinical characteristics, patients in the office-based group had statistically significantly higher rates of all adverse events (incidence rate ratio [IRR]=2.07, 95% CI [1.82, 2.36]), and specific adverse events including thromboembolism (IRR=4.38, 95% CI [3.29, 5.84]), major bleed (IRR=1.45, 95% CI [1.28, 1.64]), and stroke (IRR=1.30, 95% CI [1.05, 1.61]) than patients in the patient self-testing group. Office-based patients also had a statistically significant higher rate of emergency department visits than patient self-testing patients (IRR = 1.65, 95% CI [1.47, 1.84]).

CONCLUSIONS/RELEVANCE

This analysis of real-world claims data shows lower rates of stroke, thromboembolism, and major bleeding, as well as fewer emergency department visits, with patient self-testing compared to office-based/lab INR monitoring. Our finding that PST is safe and effective among current users suggests that more patients may benefit from its use.

Fixed- Versus Variable-Dose Prothrombin Complex Concentrate for the Emergent Reversal of Vitamin K Antagonists: A Systematic Review and Meta-Analysis

OBJECTIVES

Four-factor prothrombin complex concentrate (4-PCC) is recommended for rapid reversal of vitamin K antagonists (VKAs) such as warfarin, yet optimal dosing remains uncertain.

DATA SOURCES

A systematic review was conducted of PubMed, Embase, and Ovid MEDLINE (Wolters Kluwer) databases from January 2000 to August 2023 for clinical studies comparing fixed- vs. variable-dose 4-PCC for emergent VKA reversal with at least one reported clinical outcome.

STUDY SELECTION

Abstracts and full texts were assessed independently and in duplicate by two reviewers.

DATA EXTRACTION

Data were extracted independently and in duplicate by two reviewers using predefined extraction forms.

DATA SYNTHESIS

The analysis comprised three randomized trials and 16 cohort studies comprising a total of 323 participants in randomized trials (161 in fixed dosage and 162 in variable dosage) and 1912 patients in cohort studies (858 in fixed-dose and 1054 in variable dose). Extracranial bleeding was the predominant indication, while intracranial hemorrhage varied. Overall, a fixed-dose regimen may be associated with a lower dose of 4-PCC and results in a reduction in 4-PCC administration time compared with a variable-dose regimen. A fixed-dose regimen also likely results in increased clinical hemostasis. While there is no clear difference between the two regimens in terms of achieving a goal international normalized ratio (INR) less than 2, a fixed-dose regimen is less likely to achieve a goal INR less than 1.5. High certainty evidence indicates that the fixed-dose regimen reduces both mortality and the occurrence of thromboembolic events. Additional subgroup analyses provides exploratory data to guide future studies.

CONCLUSIONS

A fixed-dose regimen for 4-PCC administration provides benefits over a variable-dose regimen in terms of dose reduction, faster administration time, improved clinical hemostasis, and reduced mortality and thromboembolic events. Further studies are warranted to better refine the optimal fixed-dose regimen.

Transition of management strategies and long-term outcomes in cancer-associated venous thromboembolism from the warfarin era to the direct oral anticoagulant era

BACKGROUND

There have been still limited data on the transition of management strategies and clinical outcomes after introduction of direct oral anticoagulant (DOAC) for cancer-associated venous thromboembolism (VTE) in the real-world clinical practice.

METHODS

Using the 2 series of multicenter COMMAND VTE registries in Japan enrolling consecutive patients with acute symptomatic VTE, we compared 695 patients with cancer-associated VTE in the Registry-1 of the warfarin era and 1507 patients in the Registry-2 of the DOAC era.

RESULTS

Regarding oral anticoagulation therapy, 576 patients (82.9 %) in the Registry-1 received warfarin, whereas 1119 patients (79.6 %) in the Registry-2 received DOACs. The cumulative 3-year incidence of discontinuation of anticoagulation was not significantly different between the 2 registries (56.7 % vs. 62.7 %, P = 0.11). The cumulative 5-year incidence of recurrent VTE was significantly lower in the Registry-2 than in the Registry-1 (17.7 % vs. 10.1 %, P < 0.001). The cumulative 5-year incidence of major bleeding was significantly lower in the Registry-2 than in the Registry-1 (26.6 % vs. 20.4 %, P = 0.045). The proportion of gastrointestinal bleeding numerically increased from the Registry-1 to the Registry-2 (46.7 % and 49.5 %), whereas that of intracranial bleeding numerically decreased from the Registry-1 to the Registry-2 (17.1 % and 14.1 %).

CONCLUSIONS

In the current historical comparison of cancer-associated VTE between the 2 large real-world registries, there was a striking change in the treatment strategies with decreased risks of recurrent VTE and major bleeding in the DOAC era compared with those in the warfarin era, while there seemed to be unmet needs of DOAC-related gastrointestinal bleeding.

CLINICAL TRIAL REGISTRATION

URL: http://www.umin.ac.jp/ctr/index.htm UNIQUE IDENTIFIER: UMIN000044816.

Clinical Care Pathway and Management of Major Bleeding Associated with Nonvitamin K Antagonist Oral Anticoagulants: A Modified Delphi Consensus from Saudi Arabia and UAE

Background

The nonvitamin K antagonist oral anticoagulants (NOACs) have become the mainstay anticoagulation therapy for patients requiring oral anticoagulants (OACs) in the Gulf Council Cooperation (GCC) countries. The frequency of NOAC-associated major bleeding is expected to increase in the Emergency Department (ED). Nonetheless, we still lack local guidelines and recommendations for bleeding management in the region. The present Delphi-based consensus aims to establish a standardized and evidence-based clinical care pathway for managing NOAC-associated major bleeding in the Kingdom of Saudi Arabia (KSA) and the United Arab Emirates (UAE).

Methods

We adopted a three-step modified Delphi method to develop evidence-based recommendations through two voting rounds and an advisory meeting between the two rounds. A panel of 11 experts from the KSA and UAE participated in the consensus development.

Results

Twenty-eight statements reached the consensus level. These statements addressed key aspects of managing major bleeding events associated with NOACs, including the increased use of NOAC in clinical practice, clinical care pathways, and treatment options.

Conclusion

The present Delphi consensus provides evidence-based recommendations and protocols for the management of NOAC-associated bleeding in the region. Patients with major DOAC-induced bleeding should be referred to a well-equipped ED with standardized management protocols. A multidisciplinary approach is recommended for establishing the association between NOAC use and major bleeding. Treating physicians should have prompt access to specific reversal agents to optimize patient outcomes. Real-world evidence and national guidelines are needed to aid all stakeholders involved in NOAC-induced bleeding management.

Effect of rt-PA on Shear Wave Mechanical Assessment and Quantitative Ultrasound Properties of Blood Clot Kinetics In Vitro

OBJECTIVE

The consequences associated with blood clots are numerous and are responsible for many deaths worldwide. The assessment of treatment efficacy is necessary for patient follow-up and to detect treatment-resistant patients. The aim of this study was to characterize the effect of treatment on blood clots in vitro using quantitative ultrasound parameters.

METHODS

Blood from 10 pigs was collected to form three clots per pig in gelatin phantoms. Clots were subjected to 1) no treatment, 2) rt-PA (recombinant tissue plasminogen activator) treatment after 20 minutes of clotting, and 3) rt-PA treatment after 60 minutes of clotting. Clots were weighted before and after the experiment to assess the treatment effect by the mass loss. The clot kinetics was studied over 100 minutes using elastography (Young's modulus, shear wave dispersion, and shear wave attenuation). Homodyne K-distribution (HKD) parameters derived from speckle statistics were also studied during clot formation and dissolving (diffuse-to-total signal power ratio and intensity parameters).

RESULTS

Treated clots loosed significantly more mass than non-treated ones (P < .005). A significant increase in Young's modulus was observed over time (P < .001), and significant reductions were seen for treated clots at 20 or 60 minutes compared with untreated ones (P < .001). The shear wave dispersion differed for treated clots at 60 minutes versus no treatments (P < .001). The shear wave attenuation decreased over time (P < .001), and was different for clots treated at 20 minutes versus no treatments (P < .031). The HKD intensity parameter varied over time (P < .032), and was lower for clots treated at 20 and 60 minutes than those untreated (P < .001 and P < .02).

CONCLUSION

The effect of rt-PA treatment could be confirmed by a decrease in Young's modulus and HKD intensity parameter. The shear wave dispersion and shear wave attenuation were sensitive to late and early treatments, respectively. The Young's modulus, shear wave attenuation, and HKD intensity parameter varied over time despite treatment.

Smaller nadroparin dose reductions required for patients with renal impairment: A multicenter cohort study

BACKGROUND

Guidelines advise 50 % and 25 % dose reduction of the therapeutic nadroparin dose (86 IU/kg) in patients with eGFR 15-29 and 30-60 ml/min respectively. For monitoring, peak anti-Xa levels are suggested. Data lack whether this results in therapeutic anti-Xa levels or in anti-Xa levels that are comparable to those of patients without renal impairment.

AIMS

To determine dose ranges in patients with renal impairment that result in therapeutic anti-Xa levels and to determine the percentage of the 86 IU/kg dose that results in anti-Xa levels normally occurring in patients without renal impairment.

METHODS

A retrospective cohort study was conducted in five hospitals. Patients ≥18 years of age, with an eGFR ≥ 15 ml/min were included. The first correctly sampled peak (i.e. 3-5 h after ≥ third administration, regardless of dose per patient) was included. Simulated prediction models were developed using multiple linear regression.

RESULTS

770 patients were included. eGFR and hospital affected the association between dose and anti-Xa level. The doses for peak anti-Xa levels of 0.75 IU/ml differed substantially between hospitals and ranged from 55 to 91, 65-359 and 68-168 IU/kg in eGFR 15-29, 30-60 and > 60 ml/min/1.73m2, respectively. In eGFR 15-29 and 30-60 ml/min/1.73m2, doses of 75 % and 91 % of 86 IU/kg respectively, were needed for anti-Xa levels normally occurring in patients with eGFR > 60 ml/min.

CONCLUSION

We advise against anti-Xa based dose-adjustments as long as anti-Xa assays between laboratories are not harmonized and an anti-Xa target range is not validated. A better approach might be to target levels similar to eGFR > 60 ml/min/1.73m2, which are achieved by smaller dose reductions.

Risk Stratification for Supratherapeutic Peak Anti-Xa Levels in Adult Patients on Therapeutic Enoxaparin

BACKGROUND

The American Society of Hematology Guidelines for the management of venous thromboembolism recommend against the use of anti-Xa monitoring for assessing enoxaparin dosing based on a low level of evidence associating supratherapeutic levels with an increased risk of bleeding. However, institutions still utilize anti-Xa levels in select patient populations with altered volume of distribution and/or excretion to monitor and adjust therapy.

OBJECTIVE

The primary objective of this study was to identify risk factors associated with supratherapeutic peak anti-Xa levels (≥1.10 IU/mL) for patients receiving therapeutic enoxaparin.

METHODS

This was a retrospective single-center study performed at an academic tertiary care hospital. Patients who received enoxaparin at 1 mg/kg twice daily and peak anti-Xa monitoring were separated into supratherapeutic and therapeutic/subtherapeutic cohorts.

RESULTS

A total of 436 patients were screened, and 215 were included, with a mean age of 62 years. There were 108 in the therapeutic/subtherapeutic cohort and 107 in the supratherapeutic cohort. Acute kidney injury (AKI), body mass index (BMI), weight, female sex, intensive care unit (ICU) service, Sequential Organ Failure Assessment (SOFA) score ≥4, and creatinine clearance at the time of peak anti-Xa level collection were associated with supratherapeutic anti-Xa levels in univariate models. Adjusted logistic regression models were created and identified BMI in the 30 to 34.9 kg/m2 (odds ratio [OR] 4.35; 95% confidence interval [CI] 1.70-11.13, P < 0.005) and ≥35 kg/m2 (OR 6.75; 95% CI 3.05-14.94, P < 0.005) and AKI (OR 2.62; 95% CI 1.04-6.62, P = 0.042) as significant risk factors for supratherapeutic anti-Xa levels.

CONCLUSION AND RELEVANCE

Our study identified BMI ≥ 30 kg/m2, AKI, female sex, ICU service, SOFA score ≥4, and creatinine clearance as risk factors for supratherapeutic anti-Xa levels in patients receiving 1 mg/kg twice daily dosing of enoxaparin. Further research should be done to provide evidence for the association between anti-Xa levels and bleeding risk.

The use of andexanet alfa vs. 4-factor prothrombin complex concentrates in the setting of life-threatening intracranial hemorrhage

OBJECTIVE

Andexanet alfa is a targeted reversal agent for life threatening hemorrhage associated with direct acting oral anticoagulants (DOACs), but there is uncertainty regarding the benefit when compared to 4-factor prothrombin complex concentrate (4F-PCC) for this indication. We investigated the clinical outcomes and cost associated with reversal of DOACs in the setting of life-threatening intracranial hemorrhage (ICH).

METHODS

A retrospective evaluation was conducted to evaluate patients with ICH in the setting of anticoagulation with DOAC from 9/1/2013 to 4/30/2020. Patients were included in the study if they received reversal with either andexanet alfa or 4F-PCC.

RESULTS

Eighty-nine patients were included in the study. There was no statistically significant difference in 30-day mortality between patients who received andexanet alfa or 4F-PCC (52% vs. 35%, P  = 0.14). Radiographic stability of bleed was identified in 57% of patients receiving andexanet alfa vs. 58% of patients receiving 4F-PCC ( P  = 0.93). Median length of stay was not different between the andexanet alfa and 4F-PCC populations (7 days [IQR 6 - 12] vs. 6 days [IQR 3-12], P  = 0.66). Median cost of reversal agent was higher in patients receiving andexanet alfa compared to 4F-PCC ($15 000 [IQR 15 000-$27 000] vs. $11 650 [IQR $8567-$14 149]).

CONCLUSION

Among patients with life-threatening intracranial hemorrhage in the setting of DOAC therapy, no clinical differences were observed with respect to selection of reversal agent. Prothrombin complex concentrates remain a viable alternative to reversal of DOAC therapy though multicenter, randomized, prospective studies are needed to further evaluate the role of 4F-PCC in the reversal of DOAC therapy.

Appraising the quality standard of clinical practice guidelines related to central venous catheter-related thrombosis prevention: a systematic review of clinical practice guidelines

OBJECTIVE

To evaluate the quality and analyse the content of clinical practice guidelines regarding central venous catheter-related thrombosis (CRT) to provide evidence for formulating an evidence-based practice protocol and a risk assessment scale to prevent it.

DESIGN

Scoring and analysis of the guidelines using the AGREE II and AGREE REX scales.

DATA SOURCES

Pubmed, Embase, Cochrane Library, Web of Science, CNKI, Wanfang, VIP, and the Chinese Biomedical Literature, and the relevant websites of the guideline, were searched from 1 January 2017 to 26 March 2022.

ELIGIBILITY CRITERIA

Guidelines covering CRT treatment, prevention, or management were included from 1 January 2017 to 26 March 2022.

DATA EXTRACTION AND SYNTHESIS

Three independent reviewers systematically trained in using the AGREE II and AGREE REX scales were selected to evaluate these guidelines.

RESULTS

Nine guidelines were included, and the quality grade results showed that three were at A-level and six were at B-level. The included guidelines mainly recommended the prevention measure of central venous CRT from three aspects: risk screening, prevention strategies, and knowledge training, with a total of 22 suggestions being recommended.

CONCLUSION

The overall quality of the guidelines is high, but there are few preventive measures for central venous CRT involved in the guidelines. All preventive measures have yet to be systematically integrated and evaluated, and no risk assessment scale dedicated to this field has been recommended. Therefore, developing an evidence-based practice protocol and a risk assessment scale to prevent it is urgent.

Clinical outcomes associated with anti-Xa-monitored enoxaparin for venous thromboembolism prophylaxis

STUDY OBJECTIVE

The objective of the study was to assess clinical outcomes (composite of any venous thromboembolism [VTE], any bleeding, and mortality) associated with anti-Xa monitoring in the 30 days following enoxaparin initiation for VTE prophylaxis.

DESIGN

Retrospective cohort study.

SETTING

Hospital within an academic healthcare system.

PATIENTS

Propensity score-matched hospitalized adults receiving enoxaparin for VTE prophylaxis.

INTERVENTION

Low-molecular-weight heparin anti-Xa monitoring.

MEASUREMENTS AND MAIN RESULTS

During the 13-month study period, a total of 6611 patients received enoxaparin for VTE prophylaxis, 301 in the anti-Xa monitored group and 6310 in the unmonitored group (4.6% received monitoring). The mean age was 52.9 years and 52% of patients were male. The mean body mass index was 31 kg/m2 and the mean creatinine clearance was 109 mL/min. Twenty percent of patients had active cancer. The most common indication for enoxaparin prophylaxis was hospitalization for medical illness (52%) followed by nonorthopedic surgery (37%). The adjusted odds ratio for the primary outcome comparing monitored to unmonitored patients was 1.26 (95% confidence interval, 0.75-2.11). None of the between-group differences in the individual components of the composite outcome were statistically significant.

CONCLUSIONS

Thirty-day clinical outcomes in patients receiving enoxaparin for VTE prophylaxis were not improved by anti-Xa monitoring. Our results support current evidence-based guideline recommendations against anti-Xa monitoring for patients receiving enoxaparin for VTE prophylaxis.

Venous thromboembolism management in people with cystic fibrosis

BACKGROUND

Rates of venous thromboembolism (VTE) are increasing in people with cystic fibrosis (PwCF). Providers treating VTE in PwCF have reported low confidence concerning anticoagulant drug selection, dose, duration, and drug-drug interactions. As there are currently no published reports regarding management of VTE in PwCF, our objective was to describe the management of VTE in PwCF.

METHODS

PwCF and VTE at the University of Utah Health were identified through electronic medical record searches. Patients were categorized into one of three treatment groups: warfarin, direct oral anticoagulant (DOAC), and low molecular weight heparin (LMWH). The primary outcome was episodes of major bleeding. Secondary outcomes included clinically relevant nonmajor (CRNM) bleeding.

RESULTS

Nine PwCF with a total of 12 unique VTE episodes were included in the study, with all but one episode associated with a peripherally inserted central catheter (PICC). Of the 12 VTE cases, 25% were treated with warfarin, 50% with a DOAC, and 25% with LMWH. There were no episodes of major bleeding and only one episode of CRNM bleeding (Hemoptysis) in the LMWH group. All anticoagulant doses and durations generally followed guidelines for persons without CF. DOACs were the most common VTE treatment, at doses and duration consistent with guidelines for persons without CF, with no major or CRNM bleeding.

CONCLUSION

VTE treatment in PwCF is generally consistent with guidelines for persons without CF with low rates of bleeding. DOACs are a potential option for treatment of VTE in PwCF, but more research is needed.

Is reversal of anticoagulants necessary in neurologically intact traumatic intracranial hemorrhage?

INTRODUCTION

Falls are the leading cause of injury in older individuals, with intracranial hemorrhage (ICH) being a common complication. Anticoagulants, such as vitamin K antagonist and direct oral anticoagulants, are increasingly utilized, and clinicians may question the necessity of reversal in patients with minor ICH, especially in the setting of increased risk of adverse events. This study aimed to identify a population of patients with minor traumatic ICH at low risk for poor-neurologic status where anticoagulant reversal may not improve outcomes.

METHODS

This retrospective cohort study utilized data accessed from 35 trauma centers from 2018 to 2021. Patients included had a preinjury anticoagulant regimen, ICH due to blunt trauma, Glasgow Coma Scale score of 15, an Abbreviated Injury Scale (AIS) head score from 2 to 4, and an AIS of ≤1 for non-head regions within 24 h of hospital arrival. Patients were excluded if they required an emergent neurosurgical procedure or were on a preinjury purinergic-P2 receptor-12 protein (P2Y12) inhibitor. The primary outcome was the rate of in-hospital mortality or hospice.

RESULTS

There were 654 patients on preinjury anticoagulation who were included with a minor traumatic ICH without neurologic deficits. Overall, 263 patients were reversed and 391 were not reversed. Twelve (4.6%) patients with in-hospital mortality or hospice were reversed compared with 19 (4.91%) patients who were not reversed (p = 0.861). A composite of hospital complications occurred in 21 (8%) reversed patients and 34 (8.7%) not reversed patients (p = 0.748). The average intensive care unit length of stay was 1.4 ± 3.4 days in the reversed group and 1.1 ± 1.8 days in the not reversed group (p = 0.069).

CONCLUSION

This study found no difference in hospital outcomes between patients with minor traumatic ICH on oral anticoagulants who were neurologically intact that were reversed versus those who were not reversed. Further studies should continue to define the subset of traumatic ICH patients who may not require reversal of anticoagulation.

Clinical Characteristics and Outcomes of Patients With Venous Thromboembolism Receiving Edoxaban in the Real World

BACKGROUND

The effectiveness and safety of edoxaban for venous thromboembolism (VTE) in unselected real-world patients have not been fully evaluated.

METHODS AND RESULTS

In the Japanese nationwide administrative database, we identified 6,262 VTE patients in whom edoxaban was initiated; these patients were divided into 3 groups based on their index doses: 15 mg/day (n=235), 30 mg/day (n=4,532), and 60 mg/day (n=1,495). We evaluated patient characteristics, recurrent VTEs, and a composite endpoint of intracranial hemorrhage (ICH) and gastrointestinal (GI) bleeding. Patient characteristics among the 15-, 30-, and 60-mg edoxaban groups varied widely regarding several aspects, including age (mean 81.0, 76.2, and 65.0 years, respectively) and body weight (mean 49.5, 51.8, and 70.3 kg, respectively). At 180 days, the cumulative incidence of recurrent VTEs in the 15-, 30-, and 60-mg edoxaban groups was 4.4%, 2.6%, and 1.8%, respectively, whereas that of ICH or GI bleeding was 7.3%, 5.4%, and 3.3%, respectively. Subgroup analyses showed that the cumulative incidence of ICH or GI bleeding in patients in the 15-mg edoxaban group was 3.6% for patients aged ≥80 years, 8.4% for those with a body weight <60 kg, and 31.3% for those with renal dysfunction.

CONCLUSIONS

Only a minority of patients with VTEs received a super low dose (15 mg) of edoxaban, and these patients may be at higher risk of bleeding as well as VTE recurrence.

The History of Extracorporeal Membrane Oxygenation and the Development of Extracorporeal Membrane Oxygenation Anticoagulation

Extracorporeal membrane oxygenation (ECMO) was first started for humans in early 1970s by Robert Bartlett. Since its inception, there have been numerous challenges with extracorporeal circulation, such as coagulation and platelet activation, followed by consumption of coagulation factors and platelets, and biocompatibility of tubing, pump, and oxygenator. Unfractionated heparin (heparin hereafter) has historically been the defacto anticoagulant until recently. Also, coagulation monitoring was mainly based on bedside activated clotting time and activated partial thromboplastin time. In the past 50 years, the technology of ECMO has advanced tremendously, and thus, the survival rate has improved significantly. The indication for ECMO has also expanded. Among these are clinical conditions such as postcardiopulmonary bypass, sepsis, ECMO cardiopulmonary resuscitation, and even severe coronavirus disease 2019 (COVID-19). Not surprisingly, the number of ECMO cases has increased according to the Extracorporeal Life Support Organization Registry and prolonged ECMO support has become more prevalent. It is not uncommon for patients with COVID-19 to be on ECMO support for more than 1 year until recovery or lung transplant. With that being said, complications of bleeding, thrombosis, clot formation in the circuit, and intravascular hemolysis still remain and continue to be major challenges. Here, several clinical ECMO experts, including the "Father of ECMO"-Dr. Robert Bartlett, describe the history and advances of ECMO.

Top 25 Medications the Plastic and Reconstructive Surgery Trainee Should Know for an Emergency Medicine Department Consult

SUMMARY

Plastic surgery trainees are often called to render care in the emergency department (eg, for established patients, trauma, burns). Broad-based knowledge in pharmacotherapeutics during these encounters is critical. This includes an understanding of pain medications, anxiolytics, local anesthetics, antibiotics, anticoagulants, antidotes, and more to ensure optimal patient care. The purpose of this report is to describe 25 frequently used and other important medications that plastic surgery trainees should know for an adult emergency department encounter.

Efficacy and Safety of Rivaroxaban Versus Enoxaparin in Prevention of Recurrence of Venous Thrombo-Embolism Events in Cancer Patients: A Meta-Analysis

OBJECTIVE

To examine the effectiveness of rivaroxaban compared to enoxaparin in patients diagnosed with cancer and venous thromboembolism.

METHODS

A search of Pub Med, Scopus, and Google Scholar, from inception through April 2023 was conducted. Articles comparing rivaroxaban with enoxaparin in patients with cancer and VTE/PE/DVT were included. Review Manager Version 5.2 was utilised for the analysis of the following outcomes; VTE, PE, DVT, major bleeding, and mortality.

RESULTS

A total of 8 articles and 2276 patients were included in the final analysis. Pooled analysis showed that rivaroxaban had a statistically insignificant reduced association with VTE occurrence (RR:0.83, 95% CI:0.58-1.18, P:0.3) as well as a statically insignificant reduction in major bleeding (RR:0.79, 95% CI:0.53-1.18, P:0.25). Analysis showcased that there was an insignificant reduction of mortality rivaroxaban as compared to enoxaparin (RR:0.74, 95% CI: 0.46-1.20, P:0.23).

CONCLUSION

Rivaroxaban can serve as a viable alternative to enoxaparin, with no appreciable drawbacks, for preventing and managing VTE in patients with malignancy.

Use of Andexanet Alfa for Factor Xa Inhibitor Reversal in US Verified Trauma Centers: A National Survey

Direct oral factor Xa inhibitors are replacing vitamin K-dependent antagonists as anticoagulation treatment in many clinical scenarios. Trauma centers are noting an increase in patients presenting on these medications. The 2018 Food and Drug Administration approval of andexanet alfa provides an alternative anticoagulation reversal. Barriers may limit utilization of new medications including a lack of grade 1A evidence supporting the use of prothrombin complex concentrate (PCC) versus andexanet alfa and cost. To evaluate barriers of andexanet alfa utilization by trauma surgeons, a 15-question survey was conducted. There was a 9% completion rate (n = 89). The results revealed 23.5% would choose andexanet alfa as first-line treatment in children, and 25.8% as first-line treatment in adults. The majority of respondents, 64.7% and 67.4%, would use PCC preferentially in children and adults, respectively. Respondents indicated that cost burden was an overriding factor (76.3%); 42.4% cited lack of high-level efficacy data of andexanet alfa for reversal of factor Xa inhibitors. Additional double-blinded multi-institutional randomized controlled trials comparing 4F-PCC and andexanet alfa for factor Xa inhibitor reversal are needed to support efficacy especially with the increased cost associated.

Clinical and biochemical footprints of inherited metabolic disease. XVI. Hematological abnormalities

Many classical inherited metabolic diseases (IMDs) are associated with significant hematological complications such as anemia or thrombosis. While these may not be the prominent presenting feature of these conditions, management of these issues is important for optimal outcomes in people with IMDs. Some disorders that are included in the nosology of inherited metabolic disorders, such as inherited disorders of red cell energy metabolism, have purely hematological features, and have typically been cared for by a hematologist. In the 16th issue of the Footprints series, we identified 265 IMDs associated with hematological abnormalities. We review the major hematological manifestations of IMDs, suggest further investigation of hematological findings, and discuss treatment options available for specific hematological complications of IMDs.

Anticoagulation strategies and long-term recurrence in patients with venous thromboembolism in the era of direct oral anticoagulants

BACKGROUND

There has been limited data on anticoagulation strategies and long-term recurrence in patients with venous thromboembolism (VTE) in the era of direct oral anticoagulant (DOAC).

METHODS

The COMMAND VTE Registry-2 is a multicenter retrospective cohort study enrolling 5197 consecutive patients with acute symptomatic VTE between January 2015 and August 2020 among 31 centers in Japan. In this primary report, the entire cohort was divided into 5 groups; major transient risk factors (N = 475, 9.1%), minor transient risk factors (N = 788, 15%), unprovoked (N = 1913, 37%), non-malignant persistent risk factors (N = 514, 9.9%), and active cancer (N = 1507, 29%) groups.

RESULTS

DOACs were administered in 79% of patients who received oral anticoagulants. Discontinuation of anticoagulant at 1 year was most frequent in the major transient risk factors group (57.2%, 46.3%, 29.1%, 32.0%, and 45.6%). The cumulative 5-year incidence of recurrent VTE was lowest in the major transient risk factors group (2.6%, 6.4%, 11.0%, 12.1%, and 10.1%, P < 0.001). The cumulative 5-year incidence of major bleeding was highest in the active cancer group (9.8%, 11.4%, 11.0%, 15.5%, and 20.4%, P < 0.001). After discontinuation of anticoagulation therapy, the cumulative 5-year incidence of recurrent VTE was highest in the unprovoked group (3.3%, 11.0%, 24.9%, 17.5%, and 11.8%, P < 0.001).

CONCLUSIONS

In this large real-world VTE registry, anticoagulation strategies and long-term recurrence widely differed depending on the baseline characteristics. Detailed risk stratifications of recurrent VTE could be useful for decision-making of anticoagulation strategies, whereas the bleeding-risk assessment might be especially important in the era of DOAC.

CLINICAL TRIAL REGISTRATION

URL: http://www.umin.ac.jp/ctr/index.htm Unique identifier: UMIN000044816.

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.