Meta-Analysis of Reversal Agents for Severe Bleeding Associated With Direct Oral Anticoagulants

Safety of direct oral anticoagulants reversal agents in older patients: an analysis of individual case safety reports of adverse drug reaction from VigiBase®

BACKGROUND

Real-world data on adverse drug reactions (ADRs) associated with idarucizumab and andexanet alfa are limited.

AIM

This study aimed to assess the frequency, the characteristics and clinical and demographic factors associated with ADRs related to their use.

METHODS

This is a retrospective analysis of ADR reports collected in Vigibase® until May 31, 2023. Multivariable logistic regression estimated reporting odds ratios (RORs) for serious ADRs, death, and thromboembolic events according to demographical and clinical covariates.

RESULTS

A total of 1095 Individual Case Safety Reports (ICSRs) reporting idarucizumab (72%) or andexanet alfa (28%) as suspected/interacting agents were collected. Most of the subjects were males (44.5%), with a median age of 78 years, and exposed to only one suspected/interacting medication (73.6%). ADRs were defined as serious in 88.6% of cases, with a total of 614 (56.1%) fatal cases. Compared to patients without concomitant medications, probability of serious ADRs and death were both higher in those receiving ≥ 5 concomitant medications in the idarucizumab subgroup (ROR 4.04 and 1.66, respectively) and in those receiving 1-4 concomitant medications in the andexanet alfa subgroup (ROR 5.66 and 4.80, respectively). Moreover, the probability of thromboembolic events was significantly lower for subjects aged > 75 years (ROR for 75-84 years 0.55; ROR for ≥ 85 years 0.50).

DISCUSSION

In real-world, ADRs associated with idarucizumab and andexanet alfa use are generally serious, resulting in death in a high percentage of subjects.

CONCLUSION

Clinicians should pay particular attention when managing individuals needing these drugs, especially if vulnerable and requiring polytherapy.

Safety and Efficacy of Stem Cell Therapy in Ischemic Stroke: A Comprehensive Systematic Review and Meta-Analysis

Background: Although recent advancements in ischemic stroke management have reduced associated mortality rates, there remains a pressing need for more reliable, efficacious, and well-tolerated therapeutic approaches due to the narrow therapeutic window of current treatment approaches. The current meta-analysis sought to evaluate the safety and efficacy of stem cell-based therapeutic options for patients with ischemic stroke. Methods: PubMed, Web of Science, and Cochrane library databases were searched to retrieve randomized controlled trials (RCTs) evaluating the efficacy and safety of stem cell therapy (SCT) in ischemic stroke patients. Key outcomes included the National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS), Barthel Index (BI), Fugl-Meyer Assessment (FMA), infarct size, and safety profile. The random effects model with the continuous method was used to calculate the pooled effect size in Review Manager 5.4.1, and subgroup analyses were performed based on demographics, stroke duration, and SCT delivery protocols. Results: A total of 18 RCTs involving 1026 patients were analyzed, with 538 in the treatment group and 488 in the control group. The mean change in NIHSS score was comparable between groups [MD = -0.80; 95% CI: -2.25, 0.65, p < 0.0001]. However, SCT showed better outcomes in mRS [MD = -0.56; 95% CI: -0.76, -0.35, p = 0.30] and BI scores [MD = 12.00; 95% CI: 4.00, 20.00, p = 0.007]. Additionally, the mean change in FMA score was significantly greater with SCT [MD = 18.16; 95% CI: 6.58, 29.75, p = 0.03]. The mean change in infarct volume also favored stem cell therapy [MD = 8.89; 95% CI: -5.34, 23.12, p = 0.08]. The safety profile was favorable, with adverse event rates comparable to or lower than controls. Conclusions: SCT offers a safe and effective approach to improving functional outcomes in stroke patients, particularly with early intervention. These findings highlight the potential of SCT in ischemic stroke rehabilitation while underscoring the need for standardized protocols and long-term safety evaluation.

Pharmacotherapy adjuncts for traumatic brain injury: A narrative review of evidence and considerations in the emergency department

Traumatic Brain Injury (TBI) remains a significant global health concern with significant impact on morbidity and mortality. This narrative review explores adjunctive pharmacologic agents to be employed by emergency medicine clinicians during Advanced Trauma Life Support (ATLS) in patients presenting with a TBI. Pharmacologic agents are commonly employed for the management of rapid sequence intubation and post-intubation analgosedation, hemodynamics, intracranial pressure, coagulopathy, seizure prophylaxis, and infection. This narrative review discusses current evidence and controversies to optimize adjunct pharmacotherapies during the acute management of TBI within the emergency department.

Anticoagulants: From chance discovery to structure-based design

Taking a historical perspective, we review the discovery, pharmacology, and clinical evaluation of the old and new anticoagulants that have been approved for clinical use. The drugs are discussed chronologically, starting in the 1880s, and progressing through to 2024. The innovations in technology used to develop novel anticoagulants came in fits and starts and reflected the advances in science and technology over these decades, whereas the shift from anecdote to evidence-based use of anticoagulants was delayed until the principles of epidemiology and biostatistics were introduced into clinical trial design and to the approval process. Hirudin, heparin, and vitamin K antagonists were discovered by chance, and were used clinically before their mechanism of action was elucidated and before their net clinical benefits were evaluated in randomized clinical trials. Subsequent anticoagulants were designed based on a better understanding of the structure and function of coagulation proteins, including antithrombin, thrombin, and factor Xa, and underwent more rigorous preclinical and clinical evaluation before regulatory approval. By simplifying oral anticoagulation, the direct oral anticoagulants have revolutionized anticoagulation care and have enhanced the uptake of anticoagulation, but bleeding has not been eliminated and there is a need for more effective and convenient anticoagulants for thrombosis triggered by the contact pathway of coagulation. The newly developed factor XIa and XIIa inhibitors have the potential to address these unmet clinical needs and are undergoing clinical evaluation for several indications. SIGNIFICANCE STATEMENT: Anticoagulant therapy is the cornerstone of treatment and prevention of thrombosis, which remains a leading cause of morbidity and mortality worldwide. Elucidation of the structure and function of coagulation enzymes, their cofactors, and inhibitors, coupled with advances in structure-based design led to the discovery of more convenient, safer, and more effective anticoagulants that have revolutionized the management of thrombotic disorders.

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.

Development of new anticoagulants targeting coagulation factor XI and prospects for clinical use

Thrombosis is a potentially fatal condition for which various anticoagulant therapies have been used for prevention and treatment. However, bleeding events remain a concern with all anticoagulant drugs. Recent evidence suggests that inhibiting coagulation factor XI (FXI) and activated FXI (FXIa) plays a greater role in the formation of pathological thrombi in thrombosis than in normal hemostatic thrombi, allowing for the potential to address these two events separately. Consequently, FXI/XIa inhibition has become the focus of anticoagulant drug research, leading to the development of numerous FXI-targeting compounds with diverse mechanisms of action. Herein, we aimed to review FXI/FXIa inhibitors under development, discussing the role of FXI in the coagulation reaction and the advantages and disadvantages associated with its deficiency. The results of a Phase II study showed that FXI/XIa inhibitors provide efficacy comparable to that of low molecular weight heparin therapy while reducing clinically significant bleeding events. Additionally, in a study of patients with atrial fibrillation, FXI/XIa inhibitors reduced bleeding events compared to those with direct oral anticoagulants. Furthermore, when combined with antiplatelet therapy, FXI/XIa inhibitors did not significantly increase bleeding risk in non-cardioembolic stroke or acute coronary syndrome. However, conflicting trial results have also been reported, highlighting the difficulty in assessing the clinical benefit of FXI/XIa inhibitors in different clinical settings, such as atrial fibrillation and acute myocardial infarction. Future large, well-designed Phase III studies are needed to evaluate the safety and efficacy of FXI/XIa inhibitors across diverse populations requiring antithrombotic therapy.

Prothrombin complex concentrate for reversal of oral anticoagulants in patients with oral anticoagulation-related critical bleeding: a systematic review of randomised clinical trials

BACKGROUND

Swift reversal of oral anticoagulation is deemed essential for the outcome of patients with anticoagulation-related critical bleeding. The aim of this systematic review was to evaluate the benefits and harms of prothrombin complex concentrate (PCC) in patients with oral anticoagulants-related critical bleeding.

METHODS

For this systematic review CENTRAL, MEDLINE, Embase, LILACS, BIOSIS, Web of Science, and clinical trial registries were systematically searched. Clinical study reports were also requested from competent authorities. Eligible for inclusion were randomised clinical trials comparing PCC versus no intervention, placebo, or other reversal interventions in participants with critical bleeding related to ongoing treatment with vitamin K antagonist (VKA) or direct oral anticoagulants (DOAC). Pre-specified primary outcomes were all-cause mortality, health-related quality of life, and serious adverse events for which meta-analyses, Trial Sequential Analysis, and GRADE assessments were conducted.

RESULTS

Three trials, randomising a total of 291 participants, evaluated PCC against two different active comparators in participants with VKA-related critical bleeding, and two trials, randomising a total of 534 participants, evaluated PCC against two different active comparators in participants with factor Xa-related critical bleeding. Among participants with VKA-related critical bleeding, meta-analyses showed no evidence of a difference between PCC versus fresh frozen plasma (FFP) when assessing all-cause mortality (risk ratio [RR] 1.05; 95% confidence interval (CI) 0.27 to 4.05; low certainty), health-related quality of life (mean difference 1.04; 95% CI - 0.94 to 3.02; very low certainty), and serious adverse events (RR 1.33; 95% CI 0.94 to 1.88; very low certainty), but information is currently sparse. Among participants with factor Xa-related critical bleeding, PCC could not be shown superior or inferior to other reversal strategies (FFP or andexanet alfa) on any patient-relevant outcome, but information is currently sparse.

CONCLUSION

Among participants with VKA or DOAC-related critical bleeding, evidence from randomised clinical trials is currently insufficient to establish if PCC is superior or inferior versus other interventions in decreasing the risk of undesirable patient-relevant outcomes or improving health-related quality of life.

Prediction and prevention of post-procedural bleedings in patients with cirrhosis

Although post-procedural bleedings are infrequent in patients with cirrhosis, they are associated with significant morbidity and mortality. Therefore, predicting and preventing such bleedings is important. Established predictors of post-procedural bleeding include high-bleeding risk procedure, severe cirrhosis and high body mass index; prognostic value of anemia, acute kidney injury and bacterial infection is more uncertain. While prothrombin time and international normalized ratio do not predict post-procedural bleeding, some evidence suggests that platelet count, whole blood thrombin generation assay and viscoelastic tests may be helpful in this context. Prevention of postprocedural bleeding involves careful management of antithrombotic drugs during the periprocedural period. Patients with cirrhosis present unique challenges due to altered pharmacokinetics and pharmacodynamics of antithrombotic drugs, but there is a lack of dedicated studies specifically focused on this patient population. Guidelines for periprocedural management of antithrombotic drugs developed for patients without liver disease are thus applied to those with cirrhosis. Some technical aspects may decrease the risk of post-procedural bleeding, namely ultrasoundguidance, opting for transjugular route rather than percutaneous route, and the level of expertise of the operator. The effectiveness of platelet transfusions or thrombopoietin-receptor agonists remains uncertain. Transfusion of fresh-frozen plasma, of fibrinogen, and administration of tranexamic acid are not recommended for reducing post-procedural bleeding in patients with cirrhosis. In conclusion, prediction of post-procedural requires a global approach taking into account the patients characteristics, the risk of the procedure, and the platelet count. There is little data to support prophylactic correction of hemostasis, and dedicated studies are needed.

Real-world clinical practice of current periprocedural anticoagulation management in catheter ablation of atrial fibrillation: Data from a large prospective ablation registry

Background

The guidelines recommend anticoagulation management with uninterrupted warfarin or direct thrombin inhibitors (DTIs) during the atrial fibrillation (AF) ablation periprocedural period.

Objectives

To clarify the Japanese real-world latest periprocedural anticoagulation management during AF ablation.

Methods

This multicenter observational study included 6232 consecutive AF patients (68.7 ± 10.9 years, 4346 men) who underwent periprocedural anticoagulation therapy using direct oral anticoagulants (DOACs) between January 2022 and August 2023.

Results

The mean CHADS2 and CHA2DS2VASc scores were 1.2 ± 1.1 and 2.3 ± 1.5. Bleeding and thromboembolic events occurred in 79 (1.3%) and eight (0.12%) patients. During the periprocedural period, factor Xa inhibitors (FXaIs) were used in 3063 patients (rivaroxaban in 624, apixaban in 1093, and edoxaban in 1345) and DTIs in 3170 including 2583 in whom DTIs were switched from FXaIs. Both the bleeding (0.85% vs. 1.69%, p = .003) and thromboembolic event rates (0.03% vs. 0.23%, p = .036) were significantly lower in the DTI- than FXaI-group. A multivariate analysis showed periprocedural FXaI use was significantly associated with both bleeding events (odds ratio [OR] = 1.92, 95% confidence interval [CI] = 1.20-3.08, p = .006) and cardiac tamponade (OR = 2.74, 95% CI = 1.27-5.9, p = .01). The interval between the last DOAC administration and the procedure was significantly shorter in the DTI- than FXaI-group (4.2 ± 4.9 vs. 19.3 ± 10.7 h, p < .01). In the FXaI-group, the bleeding rate tended to be lower in the minimally interrupted (n = 2105) than uninterrupted group (n = 821) (1.47% vs. 2.56%, p = .06). Two patients in the uninterrupted FXaI-group required surgical management for cardiac tamponade.

Conclusions

Our multicenter real-world data demonstrated that anticoagulation with DTIs was a reasonable periprocedural anticoagulation regimen to reduce periprocedural complications.

Anticoagulant Management After Emergency Surgery or Major Bleeding in Anticoagulated Patients-Results of the Prospective RADOA Registry

Background: Major bleeding or emergency surgery are the most frequently observed emergency situations in patients anticoagulated with vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs). The restart of anticoagulation after these situations is a therapeutic dilemma. Methods: The prospective RADOA registry is an observational, noninterventional multicenter registry that documents the management of severe bleeding or emergency surgery in patients treated with VKAs or DOACs. In this substudy, we analyzed time point, type, and dosage of anticoagulant resumption after emergency situations. Results: Overall, 78 emergency surgery patients and 193 major bleeding patients were analyzed. Median age was similar in the VKA- and DOAC-treated groups (emergency surgery: 77 years, major bleeding: 79 years). Anticoagulants were restarted significantly earlier after emergency surgery compared to major bleeding, with no difference between the VKA and DOAC groups. While patients after cardiothoracic surgery received UFH intravenously, patients with trauma or having received abdominal surgery were mainly treated with prophylactic LMWH s.c.. After major bleeding, the majority of patients were treated with prophylactic LMWH. None of the patients in the emergency surgery group and 17% (4/24) of the major bleeding group with recurrent bleeding (12%, 24/193) experienced recurrent bleeding after restart of anticoagulation. Thromboembolism occurred rarely in both patient groups (emergency surgery: 3%, major bleeding 4%). Conclusions: Time points of restart, type, and dosage of anticoagulants are highly diverse in this high-risk patient population. Resumption of prophylactic anticoagulation is associated with a low risk of thrombosis and should be initiated as soon as possible.

Mitral Valve Repair Versus Replacement in Patients Undergoing Concomitant Aortic Valve Replacement

AIM

Mitral valve repair (MVr) is associated with more favourable long-term outcomes than mitral valve replacement (MVR) in cases of isolated mitral valve disease suitable for repair. However, there is debate regarding whether the superiority of MVr extends to patients with concomitant aortic and mitral valve disease. Therefore, this meta-analysis was conducted to compare the survival benefits between aortic valve replacement (AVR) plus MVr with a double valve replacement (DVR).

METHOD

A comprehensive literature search was conducted on PubMed, EMBASE, and Cochrane until 20 October 2022. Studies comparing MVr and MVR in patients undergoing concomitant AVR were included. The primary outcome was long-term survival. The secondary outcomes were early mortality, mitral valve reoperation, and valve-related adverse events.

RESULTS

Sixteen studies with a total of 140,638 patients were included in this analysis. Patients undergoing AVR plus MVr exhibited a favourable trend in long-term survival (HR 0.85; 95% CI 0.71-1.03; p=0.10; I2=58%). The reconstructed Kaplan-Meier curve revealed that the long-term survival at 5, 10, and 15 years was higher in the AVR plus MVr (80.95%, 67.63%, and 51.18%, respectively) than in the DVR group (76.62%, 61.36%, 43.21%, respectively). Aortic valve replacement plus MVr had a lower risk of early mortality (RR 0.67; 95% CI 0.58-0.79; p<0.001; I2=77%), thromboembolic events (RR 0.81; 95% CI 0.67-0.98; p=0.03; I2=5%), and haemorrhagic events (RR 0.87; 95% CI 0.78-0.98; p=0.01; I2=59%). Moreover, both groups displayed comparable rates of mitral valve reoperation (HR 1.73; 95% CI 0.86-3.48; p=0.13; I2=60%) and infective endocarditis (RR 1.60; 95% CI 0.65-3.93; p=0.31; I2=0%). However, the rate of reoperation for AVR plus MVr significantly increased in rheumatic heart disease patients (HR 3.30, 95% CI 1.66-6.59; p<0.0001).

CONCLUSIONS

Compared with DVR, AVR plus MVr was associated with favourable long-term survival, reduced early mortality risk, and a lower incidence of thromboembolic and haemorrhagic events without increasing the risk of mitral valve reoperation or infective endocarditis in unselected patients. However, higher reoperation rates were observed in rheumatic heart disease patients undergoing AVR plus MVr.

Andexanet alfa: trials just leave us with more questions

Andexanet Alfa in Acute Intracranial Hemorrhage in Patients Receiving an Oral Factor Xa Inhibitor (ANNEXA-I), the first ever randomized controlled trial of a reversal agent for direct oral anticoagulants, was published in 2024. The trial, which randomized patients with intracranial hemorrhage to andexanet alfa or usual care, was mandated by the United States Food and Drug Administration as part of its conditional approval in 2018. This approval was originally based on the single-arm trial, The Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of Factor Xa Inhibitors (ANNEXA-4). ANNEXA-I was stopped early for benefit and showed a reduction in the number of patients with significant hematoma expansion. However, the study was not powered for clinical endpoints such as disability or death and showed no difference in these outcomes. It did, however, show an increased risk of thrombosis, predominantly stroke with andexanet alfa. In this perspective, I reflect on some of the key criticisms of the trial and the implications for its interpretation.

Multidisciplinary Expert Guidance for the Management of Severe Bleeding on Oral Anticoagulation: An Algorithm for Practicing Clinicians

Bleeding complications associated with oral anticoagulant (OAC) frequently lead to emergency department visits and hospitalization. Short-term all-cause mortality after severe bleeding is substantial ranging from approximately 10% for gastrointestinal bleeding (the most frequent single site) to approximately 50% for intracranial bleeding. A protocol for multidisciplinary approach to bleeding is needed to (i) ensure rapid identification of patients at risk of adverse outcomes, (ii) optimize delivery of supportive measures, (iii) treat the source of bleeding, and (iv) administer anticoagulant reversal or hemostatic therapies judiciously for patients most likely to benefit. We convened a multidisciplinary panel of experts (emergency medicine, gastroenterology, general internal medicine, hematology, neurology, pharmacy, thrombosis) to review the literature and provide practical guidance including a corresponding algorithm for use at the point of care to assist clinicians in the management of patients with acute severe OAC-related bleeding.

Urgent Reversal of Direct Oral Anticoagulants in Critical and Life-Threatening Bleeding: A Multidisciplinary Expert Consensus

Direct oral anticoagulants (DOACs) are increasingly being used due to their improved efficacy/safety ratio and lower clinical and economic burden when compared to vitamin K antagonists. However, bleeding is still the most frequent complication associated with DOACs, and although rare, bleeding episodes can be life-threatening or critical. The impact of DOAC anticoagulation activity during a bleeding event must be evaluated according to patient clinical assessment, dosage and time from last intake, the presence of comorbidities (especially kidney and liver dysfunction), and, whenever possible, coagulation tests. Unfortunately, DOACs' anticoagulation activity is not easily or usually detectable in routine common coagulation testing. Specific DOAC tests allow for specific drug monitoring, but they are too time consuming, and are usually unavailable in routine emergency practice. If a clinically relevant DOAC plasma concentration is assumed or proven in a severe bleeding scenario, DOAC reversal is needed to restore hemostasis. This experts' consensus provides a narrative review about DOAC reversal and practical life-threatening bleeding management in several scenarios (trauma, intracranial hemorrhage and gastrointestinal bleeding), focusing on the selection of patients to whom specific reversal agents should be given.

Adverse events of direct factor Xa inhibitors: a disproportionality analysis of the FAERS database

OBJECTIVES

Direct factor Xa inhibitors rivaroxaban, apixaban, and edoxaban, commonly used direct oral anticoagulant (DOAC), are widely used to prevent and treat stroke and venous thromboembolic events in patients with atrial fibrillation (AF). This study aimed to assess and compare reports of adverse events associated with rivaroxaban, apixaban, and edoxaban, including hemorrhagic and non-hemorrhagic events.

METHODS

Reporting odds ratio (ROR), proportional reporting ratio (PRR), Medications and Health Care Products Regulatory Agency (MHRA), and the information component (IC) were used to perform a risk assessment of adverse event reports in the FDA Adverse Event Reporting System (FAERS) database for the years 2018-2022.

RESULTS

Combined with disproportionality analysis in different backgrounds, the salient risks of the three-factor Xa inhibitors varied. Rivaroxaban had the most significant risk of hemorrhage, apixaban had a higher incidence and risk of death, cardiac and cerebral adverse events, and edoxaban showed a more prominent risk in the kidneys and urinary system.

CONCLUSION

Hemorrhage is a common risk with factor Xa inhibitors, with rivaroxaban being the most significant. Apixaban and edoxaban also showed significant association with non-hemorrhagic adverse events, and increased attention to non-hemorrhagic adverse events is needed in clinical use.

Prothrombin complex concentrate for direct factor Xa inhibitor-associated bleeding or before urgent surgery

INTRODUCTION

Factor Xa inhibitor (FXaI)-associated bleeding events are common and associated with substantial morbidity. Systematic evaluation of widely available, effective, and affordable FXaI bleed management strategies is needed.

MATERIALS AND METHODS

We conducted a single-center retrospective cohort study of FXaI-treated patients presenting to a tertiary academic medical center from January 2018 to May 2019 who received 25-50 IU/kg 4F-PCC for either FXaI-associated major bleeding or urgent surgery. The primary outcome was hemostatic efficacy, and the safety outcome was the 30-day risk of thromboembolism.

RESULTS

PCC was used to treat FXaI-associated bleeding in 83 cases (79.1 %) and was given before urgent surgery in 22 cases (20.9 %). Sixty-six patients were on apixaban, 38 were on rivaroxaban and one patient was on edoxaban. Intracranial hemorrhage (ICH) and gastrointestinal bleeding accounted for most bleeds (74.7 %). Median interval between last DOAC intake and presentation to triage was 9 h [IQR 5.3-14.8] and median PCC dosing was 40.0 IU/kg [IQR 28.5-46.6]. Forty-two patients (40.0 %) had pre-PCC FXaI levels drawn with median FXaI levels of 114.5 ng/mL [IQR 70.0-175.0]. Effective hemostasis occurred in 66.7 % [95%CI 55.4-76.3] of patients receiving PCC for bleeding and surgical hemostasis was rated as normal in 95.5 % (95%CI 76.5-100.0) for patients having urgent surgery. The 30-day risk of thromboembolism was 7.6 % [95%CI 3.7-14.5] and 22.9 % [95%CI 15.8-31.8] of patients died.

CONCLUSIONS

PCC for FXaI-associated bleeding was associated with hemostatic efficacy in two-thirds of patients and thromboembolic events were uncommon. PCC represents a promising treatment strategy for FXaI-associated bleeding.

Anticoagulant Effect of Snow mountain garlic: In Vitro Evaluation of Aqueous Extract

Snow mountain garlic is traditionally eaten by Himalayan locals for its medicinal properties. Although different species of the genus Allium are known to have other biological effects, such as antiplatelet and antithrombotic activities, little is known about the anticoagulant effect of Snow mountain garlic, a member of the genus Allium. Therefore, the present study examined the in vitro anticoagulant effect of the aqueous extract, the lyophilized aqueous extract, and the isoflavone extract from the lyophilized aqueous extract of Snow mountain garlic in samples from 50 human blood donors. Compared to the control, concentrations of 25, 12.5, and 6.25 mg/100 µL lengthened the clotting times of prothrombin, and concentrations of 25 and 12.5 mg/100 µL lengthened the activated partial thromboplastin time (p ˂ 0.05). The isoflavone extract from the lyophilized aqueous extract containing isoflavones, organosulfur compounds, a polyphenol, and a steroid glycoside showed a significant effect (p ˂ 0.05) on the prothrombin time and the activated partial thromboplastin time at a dose of 20 µL (volume) compared to the control. The results regarding the use of Snow mountain garlic as a preventive measure and aid in treating thromboembolic disease are promising.

Reversal of direct oral anticoagulants: guidance from the SSC of the ISTH

The currently approved direct oral anticoagulants (DOACs) are increasingly used in clinical practice. Although serious bleeding risks are lower with DOACs than with vitamin K antagonists, bleeding remains the most frequent side effect. Andexanet alfa and idarucizumab are the currently approved specific reversal agents for oral factor (F)Xa inhibitors and dabigatran, respectively. Our prior guidance document was published in 2016, but with more information available on the utility and increased use of these reversal agents and other bleeding management strategies, we have updated this International Society on Thrombosis and Haemostasis guidance document on DOAC reversal. In this narrative review, we compare the mechanism of action of specific and nonspecific reversal agents, review the clinical data supporting their use, and provide guidance on when reversal is indicated. In addition, we briefly discuss the reversal of oral FXIa inhibitors, a new class of DOACs currently under clinical development.

International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024

The "International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024" updates and replaces the "Listing Criteria for Heart Transplantation: International Society for Heart and Lung Transplantation Guidelines for the Care of Cardiac Transplant Candidates-2006" and the "2016 International Society for Heart Lung Transplantation Listing Criteria for Heart Transplantation: A 10-year Update." The document aims to provide tools to help integrate the numerous variables involved in evaluating patients for transplantation, emphasizing updating the collaborative treatment while waiting for a transplant. There have been significant practice-changing developments in the care of heart transplant recipients since the publication of the International Society for Heart and Lung Transplantation (ISHLT) guidelines in 2006 and the 10-year update in 2016. The changes pertain to 3 aspects of heart transplantation: (1) patient selection criteria, (2) care of selected patient populations, and (3) durable mechanical support. To address these issues, 3 task forces were assembled. Each task force was cochaired by a pediatric heart transplant physician with the specific mandate to highlight issues unique to the pediatric heart transplant population and ensure their adequate representation. This guideline was harmonized with other ISHLT guidelines published through November 2023. The 2024 ISHLT guidelines for the evaluation and care of cardiac transplant candidates provide recommendations based on contemporary scientific evidence and patient management flow diagrams. The American College of Cardiology and American Heart Association modular knowledge chunk format has been implemented, allowing guideline information to be grouped into discrete packages (or modules) of information on a disease-specific topic or management issue. Aiming to improve the quality of care for heart transplant candidates, the recommendations present an evidence-based approach.

The Incidence of Thrombotic Events After the Concomitant Use of Andexanet alfa and 4-Factor Prothrombin Complex Concentrate

Limited data exists on the safety and efficacy with the concomitant use of 4 factor prothrombic complex concentrate (4F-PCC) and andexanet alfa (AA). This case series describes 7 patients at our institution who received both 4F-PCC and AA for the management of life-threatening bleeding associated with apixaban or rivaroxaban. Four patients received AA due to worsening bleeding after 4F-PCC. Of the 7 patients in this case series, 1 had a documented thrombotic event which was an acute ischemic stroke. The thrombotic event rate in our case series was similar to the incidence of thrombotic events reported with the use of AA alone. In-hospital mortality occurred in 2 of 7 patients with 1 additional patient discharged to hospice care.

Percutaneous or surgical LAAO for stroke prevention in patients with atrial fibrillation: A network meta-analysis

Background

Stroke, which is mainly caused by thrombus formation in the left atrial appendage, represents the most prevalent complication of atrial fibrillation (AF). Both percutaneous left atrial appendage occlusion (p-LAAO) and surgical LAAO (s-LAAO) are used to treat AF and prevent stroke events. However, no head-to-head randomized controlled trials (RCTs) compared these strategies.

Objective

To examine the efficacy and safety of diverse strategies for reducing stroke risk using a network meta-analysis (NMA).

Methods

PubMed, EMBASE, and Cochrane repositories were explored to identify RCTs involving p-LAAO or s-LAAO, and five were included for NMA. This investigation adhered to the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-analyses. The NMA was pooled using the Bayesian random effect framework. All findings were expressed as odds ratios accompanied by a 95 % confidence interval.The primary efficacy endpoint was any stroke (AS), and the secondary efficacy endpoint was combined AS and systematic embolism (AS/SE). The primary and secondary safety endpoints were major bleeding (MB) and all-cause death (ACD), respectively.

Results

Our meta-analysis incorporated 6337 individuals diagnosed with AF. The NMA demonstrated a reducing trend in AS and AS/SE for s-LAAO versus p-LAAO, while p-LAAO showed a benefit in reducing MB and ACD.

Conclusions

and Relevance: s-LAAO could potentially benefit individuals at elevated risk for stroke, whereas p-LAAO may be linked to a reduced likelihood of bleeding.

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.

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.

Latest advances in the reversal strategies for direct oral anticoagulants

BACKGROUND

Since the late 2000s, Europe has granted approval for various thrombotic risk-related uses of direct oral anticoagulants (DOACs). Unlike traditional anticoagulants, DOACs do not necessitate routine coagulation monitoring. Nevertheless, clinical practice often encounters bleeding events associated with these medications, making the need for effective reversal strategies evident.

OBJECTIVES

The study aims to take stock of current reversal strategies for DOACs, with a particular emphasis on the latest compounds that have been developed or are currently under development.

METHODS

For obtaining information regarding the ongoing reversal strategies and the compounds under development, we referred to ClinicalTrials website, PubMed, and Google Scholar.

RESULTS

In 2024, two specific antidotes to DOACs have already received approval when reversal of anticoagulation is needed owing to life-threatening or uncontrolled bleeding: idarucizumab that reverses the effects of dabigatran, and andexanet alfa, designed to counteract activated factor X inhibitors such as apixaban and rivaroxaban. Furthermore, ciraparantag, a potential universal reversal agent, is currently in advanced stages of clinical development. Concerns remain regarding the safety of specific reversal agents, especially concerning the risk of thrombosis. Additionally, the cost of these antidotes remains high. Consequently, nonspecific strategies to counteract anticoagulant medications, including activated charcoal, hemodialysis, and concentrates of coagulation factors, still have utility.

CONCLUSION

With the validation of specific and nonspecific antidotes, DOACs could supplant traditional oral anticoagulants. This progress represents a significant advancement in anticoagulation therapy. However, ongoing research is crucial to address remaining safety concerns of the specific reversion agents of DOACs in clinical practice.

The Relationship Between Heavy Metals and Missed Abortion: Using Mediation of Serum Hormones

Accumulating evidence suggests that heavy metal exposure may have adverse effects on the fetal development. Furthermore, disruption of serum hormone homeostasis can result in the adverse pregnancy outcomes. Therefore, this study aimed to investigate the potential association between heavy metals and missed abortion, with a focus on whether serum hormones mediate this relationship. The concentrations of heavy metals and hormones in serum were measured in this case-control study. Statistical models including, logistic regression model, principal component analysis (PCA), and weighted quantile sum (WQS) regression model were employed to examine the relationship between heavy metals, serum hormones, and missed abortion. Furthermore, the mediation analysis was performed to assess the role of serum hormones as potential mediators in this relationship. This study revealed significant associations between heavy metal exposure and missed abortion. Notable, the WQS index weight, which was mainly influenced by copper (Cu) and zine (Zn), is associated with missed abortion. Moreover, heavy metals including manganese (Mn), nickel (Ni), Zn, arsenic (As), Cu, cadmium (Cd), and lead (Pb) were found to be associated with serum levels of β-human chorionic gonadotropin (β-hCG), progesterone (P), estradiol (E2), and lactogen (HPL). In addition, the mediation analysis indicated that β-hCG explained a portion of the association (ranging from 18.77 to 43.51%) of between Mn, Ni, Zn, and As exposure and missed abortion. Serum P levels explained 17.93 to 51.70% of the association between Ni, Cu, and As exposure and missed abortion. Serum E2 levels played a significant mediating role, explaining a portion of the association (ranging from 22.14 to 73.60%) between Mn, Ni, Cu, As, Cd, and Pb exposure and missed abortion. Our results suggested that β-hCG, P, and E2 are one of the potential mediators in the complex relationship between heavy metals exposure and missed abortion. These results highlight the importance of considering both heavy metal exposure and serum hormone levels in understanding the etiology of missed abortion.

Direct Oral Anticoagulants: Probability of Recurrent Venous Thromboembolism and Bleeding Risk in an Obese Population

BACKGROUND

Direct-acting oral anticoagulants (DOACs) have become the preferred drugs for managing venous thromboembolism (VTE). Despite their advantages over vitamin K antagonists such as warfarin, their use in obese patients remains controversial with many providers reluctant to switch patients managed on warfarin. Outcome research that opts to increase provider confidence when prescribing DOACs for patients with obesity will be invaluable.

OBJECTIVE

This investigation evaluated whether patients with a body mass index (BMI) 35 kg/m2 or greater who were prescribed a DOAC had a higher risk for a recurrent VTE or bleed event relative to warfarin.

METHODS

The study was conducted in West Virginia which has the highest rate of obesity in the United States.

RESULTS

Of the total study population (1633), 2.3% (37) had a recurrent thrombotic event, 5.5% (89) had a major bleed event, and 10.7% (174) had some type of bleeding event. No individual patient characteristic was associated with recurrent thrombosis-including BMI. Older age, antiplatelet use, and taking a medication with a theoretical risk of increasing the effect of DOACs were associated with any and major bleeding events. The use of warfarin was associated with major bleeding events more frequently versus a DOAC. Body mass index was not a predictor for recurrent VTE or any bleed or major bleed events.

CONCLUSIONS

These findings support the conclusion that DOACs are an appropriate and effective drug class for the management of VTE in patients with obesity.

Dabigatran accumulation in acute kidney injury: is more better than less to prevent bleeding? A case report

Dabigatran is an oral anticoagulant that is mainly renally excreted. Despite its efficacy in preventing thromboembolic events, concerns arise regarding bleeding complications in patients with acute kidney injury. Idarucizumab is its specific antidote and reverses quickly and effectively dabigatran anticoagulation effects in situations of severe bleeding or pending surgical procedures, but its benefit beyond these two indications remains uncertain. We present a case of a woman with atrial fibrillation anticoagulated by dabigatran and admitted with Streptococcus agalactiae meningitis, acute kidney injury and dabigatran accumulation. Idarucizumab was not administered initially as she did not meet its current strict indications. However, subsequently, significant bleeding necessitated its use. A rebound increase in dabigatran concentration was associated with an intracranial hemorrhage, but the combination of additional doses of idarucizumab with hemodialysis lowered the dabigatran concentration and prevented significant rebound increases. Further investigation into the optimal management of dabigatran accumulation and acute kidney injury-associated bleeding is needed to enhance patient outcomes and safety. Early initiation of hemodialysis together with idarucizumab administration may be crucial in preventing life-threatening bleeding events in these patients.

Stroke

Stroke affects up to one in five people during their lifetime in some high-income countries, and up to almost one in two in low-income countries. Globally, it is the second leading cause of death. Clinically, the disease is characterised by sudden neurological deficits. Vascular aetiologies contribute to the most common causes of ischaemic stroke, including large artery disease, cardioembolism, and small vessel disease. Small vessel disease is also the most frequent cause of intracerebral haemorrhage, followed by macrovascular causes. For acute ischaemic stroke, multimodal CT or MRI reveal infarct core, ischaemic penumbra, and site of vascular occlusion. For intracerebral haemorrhage, neuroimaging identifies early radiological markers of haematoma expansion and probable underlying cause. For intravenous thrombolysis in ischaemic stroke, tenecteplase is now a safe and effective alternative to alteplase. In patients with strokes caused by large vessel occlusion, the indications for endovascular thrombectomy have been extended to include larger core infarcts and basilar artery occlusion, and the treatment time window has increased to up to 24 h from stroke onset. Regarding intracerebral haemorrhage, prompt delivery of bundled care consisting of immediate anticoagulation reversal, simultaneous blood pressure lowering, and prespecified stroke unit protocols can improve clinical outcomes. Guided by underlying stroke mechanisms, secondary prevention encompasses pharmacological, vascular, or endovascular interventions and lifestyle modifications.

Reversal or Repletion Treatment Strategies and Outcomes of Patients With Major Bleeding Events Managed in the Emergency Department: Large Real-Life Investigation in the Northwestern Healthcare District of Tuscany

OBJECTIVE

To verify the incidence of bleeding events in patients on ongoing anticoagulant treatment in the real world and compare the results of different reversal or repletion strategies currently available for pharmacological treatment.

METHODS

Patients managed in the emergency department (ED) with major bleeding events, on ongoing anticoagulation were stratified according to bleeding site and reversal or repletion therapy with andexanet alfa (ADX), idarucizumab (IDA), prothrombin complex concentrate (PCC), and vitamin K (Vit-K).

ENDPOINT

Death at 30 days was compared in the subgroups with cerebral hemorrhage (CH) and gastrointestinal (GI) bleeding.

RESULTS

Of the 809,397 visits in the years 2022-2023 at 6 EDs in the northwestern health district of Tuscany, 5372 patients with bleeding events were considered; 3740 were excluded due to minor bleeding or propensity score matching. Of the remaining 1632 patients with major bleeding, 548 on ongoing anticoagulation were enrolled; 334 received reversal or repletion agents. Patients with CH (n = 176) and GI bleeding (n = 108) represented the primary analysis cohorts in the study's strategic treatment assessment. Overall, 30-day survival of patients on ongoing aFXa treatment receiving on-label ADX versus off-label PCC showed a relative increase of 71%, while 30-day survival of patients on ongoing aFII receiving on-label IDA versus off-label PCC showed a relative increase of 30%; no substantial difference was found when comparing on-label PCC combined with Vit-K versus off-label Vit-K alone. Indeed, patients undergoing on-label ADX or IDA showed a statistically significant difference over off-label PCC (ADX vs. PCC: n = 15, events = 4, mean ± SD 82.50 ± 18.9, vs. 49, 13, 98.82 ± 27, respectively; analysis of variance [ANOVA] variance 8627; P < 0.001; posthoc test diff 32, 95% confidence interval: 28-35; P < 001; IDA vs. PCC: 20, 5, 32.29 ± 15.0 vs. 2, 1, 28.00 ± 0.0, respectively; ANOVA 1484; P < 0.001; posthoc test -29, -29 -29, respectively; P = n.d.). On-label PCC combined with Vit-K showed overall a slight statistically significant difference versus off-label Vit-K alone (52, 16, 100.58 ± 22.6 vs. 53, 11, 154.62 ± 29.8, respectively; ANOVA 310; P < 0.02; posthoc test 4, 0.7-7.2, respectively; P < 0.02). Data were confirmed in the group of patients with CH (ADX vs. PCC: n = 13, events = 3, mean ± SD 91.55 ± 18.6 vs. 78, 21, 108.91 ± 20.9, respectively; ANOVA variance 10,091, F = 261; P < 0.001; posthoc difference test 36, 95% confidence interval: 30-41; P < 0.001; IDA vs. PCC: 10, 2, 4.50 ± 2.5 vs. 78, 21, 108.91 ± 20.9, respectively; ANOVA 16,876,303, respectively; P < 0.001; posthoc test 41, 34-47, respectively; P < 0.001). On-label PCC combined with Vit-K showed an overall slight statistically significant difference compared with off-label Vit-K alone (P < 0.01 and P < 0.001 in the subgroups of CH and GI bleeding).

CONCLUSIONS

Patients undergoing specific reversal therapy with on-label ADX or IDA, when treated with aFXa or aFII anticoagulants, respectively, showed statistically elevated differences in 30-day death compared with off-label repletion therapy with PCC. Overall, 30-day survival of patients on ongoing aFXa or aFII receiving on-label reversal therapy with ADX or IDA compared with off-label PCC repletion agents showed an increase of 71% and 30%, respectively.

Trends in prior antithrombotic medication and risk of in-hospital mortality after spontaneous intracerebral hemorrhage: the J-ICH registry

Spontaneous intracerebral hemorrhage (SICH) remains a devastating form of stroke. Prior use of antiplatelets or warfarin before SICH is associated with poor outcomes, but the effects of direct oral anticoagulants (DOACs) remain unclear. This study aimed to clarify trends in prior antithrombotic use and to assess the associations between prior use of antithrombotics and in-hospital mortality using a multicenter prospective registry in Japan. In total, 1085 patients were analyzed. Prior antithrombotic medication included antiplatelets in 14.2%, oral anticoagulants in 8.1%, and both in 1.8%. Prior warfarin use was significantly associated with in-hospital mortality (odds ratio [OR] 5.50, 95% confidence interval [CI] 1.30-23.26, P < 0.05) compared to no prior antithrombotic use. No such association was evident between prior DOAC use and no prior antithrombotic use (OR 1.34, 95% CI 0.44-4.05, P = 0.606). Concomitant use of antiplatelets and warfarin further increased the in-hospital mortality rate (37.5%) compared to warfarin alone (17.2%), but no such association was found for antiplatelets plus DOACs (8.3%) compared to DOACs alone (11.9%). Prior use of warfarin remains an independent risk factor for in-hospital mortality after SICH in the era of DOACs. Further strategies are warranted to reduce SICH among patients receiving oral anticoagulants and to prevent serious outcomes.

Engineering and evaluation of FXa bypassing agents that restore hemostasis following Apixaban associated bleeding

Direct oral anticoagulants (DOACs) targeting activated factor Xa (FXa) are used to prevent or treat thromboembolic disorders. DOACs reversibly bind to FXa and inhibit its enzymatic activity. However, DOAC treatment carries the risk of anticoagulant-associated bleeding. Currently, only one specific agent, andexanet alfa, is approved to reverse the anticoagulant effects of FXa-targeting DOACs (FXaDOACs) and control life-threatening bleeding. However, because of its mechanism of action, andexanet alfa requires a cumbersome dosing schedule, and its use is associated with the risk of thrombosis. Here, we present the computational design, engineering, and evaluation of FXa-variants that exhibit anticoagulation reversal activity in the presence of FXaDOACs. Our designs demonstrate low DOAC binding affinity, retain FXa-enzymatic activity and reduce the DOAC-associated bleeding by restoring hemostasis in mice treated with apixaban. Importantly, the FXaDOACs reversal agents we designed, unlike andexanet alfa, do not inhibit TFPI, and consequently, may have a safer thrombogenic profile.

Andexanet alfa versus PCC products for factor Xa inhibitor bleeding: A systematic review with meta-analysis

Previous meta-analyses assessed andexanet alfa (AA) or prothrombin complex concentrate (PCC) products for the treatment of Factor Xa inhibitor (FXaI)-associated major bleeding. However, they did not include recent studies or assess the impact of the risk of bias. We conducted a systematic review with meta-analysis on the effectiveness of AA versus PCC products for FXaI-associated major bleeding, inclusive of the studies' risk of bias. PubMed and Embase were searched for comparative studies assessing major bleeding in patients using FXaI who received AA or PCC. We used the Methodological Index for NOn-Randomized Studies (MINORS) checklist and one question from the Joanna Briggs Institute (JBI) Critical Appraisal of Case Series tool to assess the risk of bias. Random-effects meta-analyses were performed to provide a pooled estimate for the effect of AA versus PCC products on hemostatic efficacy, in-hospital mortality, 30-day mortality, and thrombotic events. Low-moderate risk of bias studies were meta-analyzed separately, as well as combined with high risk of bias studies. Eighteen comparative evaluations of AA versus PCC were identified. Twenty-eight percent of the studies (n = 5) had low-moderate risk and 72% (n = 13) had a high risk of bias. Studies with low-moderate risk of bias suggested improvements in hemostatic efficacy [Odds Ratio (OR) 2.72 (95% Confidence Interval (CI): 1.15-6.44); one study], lower in-hospital mortality [OR 0.48 (95% CI: 0.38-0.61); three studies], and reduced 30-day mortality [OR 0.49 (95% CI: 0.30-0.80); two studies] when AA was used versus PCC products. When studies were included regardless of the risk of bias, pooled effects showed improvements in hemostatic efficacy [OR 1.36 (95% CI: 1.01-1.84); 12 studies] and reductions in 30-day mortality [OR 0.53 (95% CI: 0.37-0.76); six studies] for AA versus PCC. The difference in thrombotic events with AA versus PCC was not statistically significant in the low-moderate, high, or combined risk of bias groups. The evidence from low-moderate quality real-world studies suggests that AA is superior to PCC in enhancing hemostatic efficacy and reducing in-hospital and 30-day mortality. When studies are assessed regardless of the risk of bias, the pooled hemostatic efficacy and 30-day mortality risk remain significantly better with AA versus PCC.

Coagulation Tests and Reversal Agents in Patients Treated with Oral Anticoagulants: The Challenging Scenarios of Life-Threatening Bleeding and Unplanned Invasive Procedures

In clinical practice, the number of patients treated with direct oral anticoagulants (DOACs) has consistently increased over the years. Since anticoagulant therapy has been associated with an annual incidence of major bleeding (MB) events of approximately 2% to 3.5%, it is of paramount importance to understand how to manage anticoagulated patients with major or life-threatening bleeding. A considerable number of these patients' conditions necessitate hospitalization, and the administration of reversal agents may be imperative to manage and control bleeding episodes effectively. Importantly, effective strategies for reversing the anticoagulant effects of DOACs have been well recognized. Specifically, idarucizumab has obtained regulatory approval for the reversal of dabigatran, and andexanet alfa has recently been approved for reversing the effects of apixaban or rivaroxaban in patients experiencing life-threatening or uncontrolled bleeding events. Moreover, continuous endeavors are being made to develop supplementary reversal agents. In emergency scenarios where specific reversal agents might not be accessible, non-specific hemostatic agents such as prothrombin complex concentrate can be utilized to neutralize the anticoagulant effects of DOACs. However, it is paramount to emphasize that specific reversal agents, characterized by their efficacy and safety, should be the preferred choice when suitable. Moreover, it is worth noting that adherence to the guidelines for the reversal agents is poor, and there is a notable gap between international recommendations and actual clinical practices in this regard. This narrative review aims to provide physicians with a practical approach to managing specific reversal agents.

Management of patients with proximal femur fractures under DOACs

PURPOSE

In the past, preinjury direct oral anticoagulant (DOAC) intake has led to delays in time to surgery (TTS) in patients with proximal femur fractures and delays in surgery have been associated with impaired outcomes. Although healthcare institutions/federal committees have set rules for treatment within 24 h of injury, comprehensive guidelines for the perioperative management of these patients, in particular when on preinjury DOACs, are still lacking. This contribution aims to summarize the current evidence on the safe time window for surgery in patients with proximal femur fractures on preinjury DOACs and to outline therapeutic options if emergency DOAC reversal becomes necessary.

METHODS

Narrative review based upon selective review of the pertinent literature.

RESULTS

For the majority of patients with proximal femur fractures and on preinjury DOACs, early surgery appears safe as soon as medical clearance has been obtained. There may be an increase in the need for blood products but with data not yet conclusive. Work-up including assessment of remaining anticoagulant activity and potential reversal should be restricted to patients at risk for bleeding complications, in particular in the presence of renal/hepatic impairment. Methodology for rapid assessment of DOACs including quantitative/qualitative concentration levels is work in progress. In the case of bleeding, rapidly acting reversal agents are available.

CONCLUSION

Preinjury DOAC use should not routinely delay surgery in patients with proximal femur fractures.

ANMCO/SIMEU consensus document on the use of reversal agents for antithrombotic therapies in patients with ongoing bleeding or at high risk of haemorrhagic events

In recent decades, an incredible evolution in antithrombotic therapies used for treating patients with atherosclerosis, atrial fibrillation, and venous thromboembolism has been observed, leading to the availability of increasingly safe drugs. Nonetheless, bleeding complications remain a significant concern, with considerable health, social, and economic implications. To improve the acute management of patients experiencing or at risk for major bleeding events, specific reversal agents for antithrombotic drugs have been recently developed. While these agents demonstrate effectiveness in small-scale pharmacodynamic studies and clinical trials, it is imperative to balance the benefits of reversing antiplatelet or anticoagulant therapy against the risk of prothrombotic effects. These risks include the potential loss of antithrombotic protection and the prothrombotic tendencies associated with bleeding, major surgery, or trauma. This joint document of the Italian Association of Hospital Cardiologists (Associazione Nazionale Medici Cardiologi Ospedalieri) and the Italian Society of Emergency Medicine (Società Italiana di Medicina d'Emergenza-Urgenza) delineates the key features and efficacy of available reversal agents. It also provides practical flowcharts to guide their use in patients with active bleeding or those at elevated risk of major bleeding events.

Antidote vs. unspecific hemostatic agents for the management of direct oral anticoagulant-related bleeding in trauma

PURPOSE OF REVIEW

The advent of direct oral anticoagulants (DOACs) marks a significant milestone in anticoagulant treatment. However, DOACs can exacerbate bleeding, which is challenging for the treating clinician, especially when combined with traumatic injury.

RECENT FINDINGS

In major bleeding associated with DOACs, rapid reversal of the anticoagulant effects is crucial. Recent observational and nonrandomized interventional trials have demonstrated the effectiveness of the specific antidotes andexanet alfa and idarucizumab as well as the unspecific prothrombin complex concentrates (PCCs) to counteract the anticoagulant effects of DOACs. The European Society of Anaesthesiology and Intensive Care guideline for severe perioperative bleeding and the European trauma guideline propose divergent recommendations for the use of andexanet alfa and PCC to obtain hemostasis in Factor Xa inhibitor-related bleeding. The conflicting recommendations are due to limited evidence from clinical studies and the potential increased risk of thromboembolic complications after the administration of andexanet. Regarding dabigatran-associated major bleeding, both guidelines recommend the specific reversal agent idarucizumab as first-line therapy.

SUMMARY

Current guidelines recommend specific antidots and PCCs in DOAC-related major bleeding. Prospective randomized trials comparing specific vs. nonspecific hemostatic agents in the perioperative setting are needed to evaluate the effectiveness and safety of the hemostatic agents.

Early Goal-Directed Hemostatic Therapy for Severe Acute Bleeding Management in the Intensive Care Unit: A Narrative Review

This is a narrative review of the published evidence for bleeding management in critically ill patients in different clinical settings in the intensive care unit (ICU). We aimed to describe "The Ten Steps" approach to early goal-directed hemostatic therapy (EGDHT) using point-of-care testing (POCT), coagulation factor concentrates, and hemostatic drugs, according to the individual needs of each patient. We searched National Library of Medicine, MEDLINE for publications relevant to management of critical ill bleeding patients in different settings in the ICU. Bibliographies of included articles were also searched to identify additional relevant studies. English-language systematic reviews, meta-analyses, randomized trials, observational studies, and case reports were reviewed. Data related to study methodology, patient population, bleeding management strategy, and clinical outcomes were qualitatively evaluated. According to systematic reviews and meta-analyses, EGDHT guided by viscoelastic testing (VET) has been associated with a reduction in transfusion utilization, improved morbidity and outcome in patients with active bleeding. Furthermore, literature data showed an increased risk of severe adverse events and poor clinical outcomes with inappropriate prophylactic uses of blood components to correct altered conventional coagulation tests (CCTs). Finally, prospective, randomized, controlled trials point to the role of goal-directed fibrinogen substitution to reduce bleeding and the amount of red blood cell (RBC) transfusion with the potential to decrease mortality. In conclusion, severe acute bleeding management in the ICU is still a major challenge for intensive care physicians. The organized and sequential approach to the bleeding patient, guided by POCT allows for rapid and effective bleeding control, through the rational use of blood components and hemostatic drugs, since VET can identify specific coagulation disorders in real time, guiding hemostatic therapy with coagulation factor concentrates and hemostatic drugs with individual goals.

The clinical outcomes of different doses of rivaroxaban in patients with isolated distal deep vein thrombosis

OBJECTIVE

Isolated distal deep vein thrombosis (IDDVT) is defined as thrombosis involving the infrapopliteal veins. The optimal anticoagulant therapy of IDDVT remains controversial. This study aimed to assess whether reduced dose of rivaroxaban was suitable in patients with IDDVT.

METHODS

Consecutive patients with acute IDDVT were identified by reviewing the venous thromboembolism (VTE) registry databases. Outcomes including VTE recurrence, major bleeding, clinically relevant non-major (CRNM) bleeding, and death. Patients were followed until the first occurrence of any outcomes or the study end date (December 31, 2018). Hazard ratios (HRs) and 95% confidence intervals (CIs) were computed.

RESULTS

A total of 1246 patients were divided into low-dose (10 or 15 mg/day; n = 716) and standard-dose (20 mg/day; n = 530) groups. The incidences of VTE recurrence, major bleeding, CRNM bleeding, and death between the two groups were 9.64% vs 5.66%, 1.68% vs 3.02%, 4.61% vs 8.68%, and 13.83% vs 10.75%, respectively. After the inverse probability of treatment weighting, HRs for standard-dose vs low-dose of VTE recurrence, major bleeding, CRNM bleeding, and death were 0.54 (95% CI, 0.35-0.84), 1.71 (95% CI, 0.80-3.67), 2.28 (95% CI, 1.40-3.74), and 1.30 (95% CI, 0.91-1.86), respectively. For the subgroup analysis, the interaction with anticoagulation duration and treatment was evident for VTE recurrence (P for interaction = .002), but not for major bleeding. Patients with residual vein thrombosis were associated with an increased risk of VTE recurrence (HR, 1.95; 95% CI, 1.29-2.95). The interaction between risk factors and residual vein thrombosis was evident for VTE recurrence (P for interaction = .085).

CONCLUSIONS

Standard-dose rivaroxaban reduced the risk of VTE recurrence without increasing the risk of major bleeding in patients with IDDVT. Anticoagulant therapy for >1.5 months should be preferred over shorter durations. Residual vein thrombosis should be assessed as a predictor of recurrence in patients with IDDVT, especially for patients with non-transient factors.

Code ICH: A Call to Action

Intracerebral hemorrhage is the most serious type of stroke, leading to high rates of severe disability and mortality. Hematoma expansion is an independent predictor of poor functional outcome and is a compelling target for intervention. For decades, randomized trials aimed at decreasing hematoma expansion through single interventions have failed to meet their primary outcomes of statistically significant improvement in neurological outcomes. A wide range of evidence suggests that ultra-early bundled care, with multiple simultaneous interventions in the acute phase, offers the best hope of limiting hematoma expansion and improving functional recovery. Patients with intracerebral hemorrhage who fail to receive early aggressive care have worse outcomes, suggesting that an important treatment opportunity exists. This consensus statement puts forth a call to action to establish a protocol for Code ICH, similar to current strategies used for the management of acute ischemic stroke, through which early intervention, bundled care, and time-based metrics have substantially improved neurological outcomes. Based on current evidence, we advocate for the widespread adoption of an early bundle of care for patients with intracerebral hemorrhage focused on time-based metrics for blood pressure control and emergency reversal of anticoagulation, with the goal of optimizing the benefit of these already widely used interventions. We hope Code ICH will endure as a structural platform for continued innovation, standardization of best practices, and ongoing quality improvement for years to come.

Use of apixaban in children awaiting heart transplantation

BACKGROUND

The use of apixaban in the pediatric cardiac population is expanding. We describe our apixaban dosing and monitoring strategy in children and young adults awaiting heart transplantation, along with outcomes related to bleeding and thrombosis during wait-list and early post-transplant periods.

METHODS

This study is a retrospective, single-center analysis of all patients receiving apixaban while awaiting cardiac transplantation. Weight-based dosing was monitored with peak drug-specific anti-Xa chromogenic analysis. Significant post-operative bleeding defined by chest tube output or need for surgical intervention.

RESULTS

From September 2020 to December 2022, 19 patients, median age 13.5 years (6.1, 15.8 years), weighing 48.9 kg (15.4, 67.6) received apixaban while awaiting transplant. Indication for apixaban was prophylaxis (n = 18, 3 with ventricular assist devices) and treatment of thrombus (n = 1). There were no clinically relevant non-major or major bleeding, nor thrombotic events while awaiting transplant. The median time from last apixaban dose to arrival in the operating room was 23.2 h (15.6-33.8), with median random apixaban level of 37 ng/mL (28.3, 59), 6.3 h (4.8, 8.4) prior to arrival in the operating room. In this study, 32% of patients had significant post-operative bleeding based on chest tube output post-transplant or need for intervention. No patients meeting criteria for significant post-operative bleeding were thought to be attributable to apixaban.

CONCLUSIONS

Careful use of apixaban can be safe and effective while awaiting heart transplant. There was no appreciable increase in peri-operative bleeding. The use of apixaban is promising in providing safe, predictable and efficacious anticoagulation while avoiding additional patient stressors.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Comparison of Fixed Versus Weight-Based Prothrombin Complex Concentrate Dosing Strategies for Factor Xa Inhibitor Reversal

Background: Our institution introduced fixed-dose prothrombin complex concentrate (PCC) to streamline order verification and medication administration. Previous studies using fixed-dose PCC for vitamin K antagonist reversal showed comparable efficacy to weight-based dosing. Objective: To compare fixed versus weight-based PCC dosing for reversal of Factor Xa Inhibitor (FXaI) effects. Methods: Retrospective cohort study conducted at a tertiary care academic medical center. Patients who received PCC to reverse the effects of apixaban or rivaroxaban were eligible. Subjects in the fixed-dose group (5000 units or 2000 units) were compared to weight-based PCC (50 units/kg). The primary outcome was time between order entry and medication administration. Secondary outcomes included: average PCC dose, postadministration procedures, achieved hemostasis, 30-day mortality, hospital length of stay, and adverse drug events. Results: 72 patients received fixed-dose PCC and 101 received weight-based PCC. Median time between order entry and administration was 4.5 min shorter in the fixed-dose group compared to weight-based (34.5 vs 39 min, P = .10). In patients who received fixed-dose, 79.2% achieved hemostasis versus 71.3% in the weight-based group (RR = 1.11, 95% CI = 0.94-1.32). There was no difference in the number of subsequent hemorrhage-related surgeries (29.2% vs 36.7%, RR = 0.80, 95% CI = 0.51-1.24) or mortality rate (26.4% vs 35.6%, RR = 0.73, 95% CI = 0.46-1.17). There were zero adverse drug events reported. Rates of thrombosis were 2.8% and < 1% (P = .57) in the fixed and weight-based groups, respectively. Conclusion and Relevance: The fixed-dosing strategy did not reduce time to PCC administration nor impact hemostasis or mortality. These data support that the fixed-dosing method is a viable option.

[Current Management of Patients with Proximal Femur Fractures Receiving Antiplatelet and Anticoagulant Therapy]

Proximal femur fractures (PFF) pose a major challenge in elderly patients with severe comorbidities and receiving antithrombotic therapy since according to the latest guidelines the surgery should be performed as soon as possible, preferably within 24 hours, to reduce mortality and morbidity. This review outlines the practical approach to surgical management of PFF that relies on increasing evidence of safety of early surgery in patients with PFF receiving antiplatelet and anticoagulant therapy. We have also used information from the existing evidence-based guidelines for elective/planned surgery in patients with antithrombotic therapy. The practical approach can be summarised as follows: • Antiplatelet therapy - discontinuation of acetylsalicylic acid (ASA) and clopidogrel in monotherapy or in combination is not necessary prior to surgery. In case of bleeding, antifibrinolytic therapy is recommended as well as administration of platelet concentrate which is rarely needed. • In patients taking warfarin, reversal of its effects is recommended by early administration of vitamin K to allow surgery to be performed within 24 hours. Prothrombin complex concentrate (PCC) as a second-line drug is reserved for extreme cases only. Warfarin therapy is resumed 24 hours after surgery. • Direct oral anticoagulants must be discontinued 24-48 hours prior to surgery, possibly longer depending on the type of drug, time of administration of the last dose, and renal function. In extreme cases, an antidote (idarucizumab, off-label andexanet) can be administered prior to surgery, or PCC in case they are unavailable. Anticoagulation therapy is resumed in 24-48 hours. • Neuraxial anaesthesia is possible when ASA is taken by the patient and in case of effective warfarin reversal. • In early surgery and rapid restart of anticoagulant therapy, bridging therapy with LMWH is not indicated except for in cases with extreme risk of thrombosis. Key words: proximal femur fracture, antiplatelet therapy, anticoagulant therapy, perioperative management.

Occurrence rates and risk factors of in-hospital venous thromboembolism, major bleeding, and death in patients receiving fondaparinux after orthopedic surgery or trauma surgery

AIM

Fondaparinux is a synthetic anticoagulant that inhibits thrombosis by suppressing factor Xa. The efficacy of fondaparinux for orthopedic surgeries has been revealed by several foreign studies; however, relevant evidence in Chinese patients is lacking. This study intended to investigate the occurrence rate and risk factors of in-hospital venous thromboembolism (VTE), major bleeding, and death in patients receiving fondaparinux after orthopedic surgery or trauma surgery.

METHODS

Totally, 1258 patients who received fondaparinux after orthopedic surgery or trauma surgery were retrospectively enrolled. Meanwhile, in-hospital VTE, major bleeding, and death were obtained for assessment. Besides, adverse events were recorded.

RESULTS

The occurrence rates of in-hospital VTE, major bleeding, and death were 2.5%, 21.8%, and 0.0%, respectively. The multivariate logistic regression analysis revealed that only age (> 60 years vs. ≤ 60 years) (odd ratios (OR) = 3.380, P = 0.013) was independently correlated with increased risk of in-hospital VTE. Additionally, osteoarthritis diagnosis (OR = 3.826, P < 0.001), femoral head necrosis diagnosis (OR = 1.809, P = 0.034), hip replacement (vs. internal fracture fixation) (OR = 2.199, P = 0.007), knee replacement (vs. internal fracture fixation) (OR = 2.781, P = 0.002), and serum creatinine (abnormal vs. normal) (OR = 1.677, P = 0.012) were independently linked to a higher risk of in-hospital major bleeding. Moreover, the common adverse events included pain (56.6%), wound bleeding (23.0%), increased drainage (5.2%), etc. CONCLUSION: Fondaparinux realizes low occurrence rates of in-hospital VTE and major bleeding with tolerable adverse events in patients receiving orthopedic surgery or trauma surgery.

Reversal of pre-injury factor-Xa inhibitors with prothrombin complex concentrates in patients following traumatic brain injury

INTRODUCTION

There is substantial debate on the best method to reverse factor Xa-inhibitors in patients following traumatic brain injury (TBI). Prothrombin complex concentrates (PCC) have been used for this indication but their role has been questioned. This study reported failure rates with PCC in patients following TBI and as a secondary objective, compared 4-factor (4 F-PCC) and activated PCC (APCC).

MATERIAL AND METHODS

Consecutive patients with TBI on factor Xa-inhibitors admitted to one of two trauma centers were retrospectively identified. Patients with penetrating TBI, delays in PCC administration (>6 h), receipt of tranexamic acid, factor VIIa or no follow up CT-scan were excluded. The primary outcome was treatment failure defined as hematoma expansion > 20% from baseline for SDH, EDH or IPH, a new hematoma not present on the initial CT scan or any expansion of a SAH or IVH. Hematoma expansion was further categorized as symptomatic or asymptomatic, designated by a change in the motor GCS score, neurologic exam or change ≥ 3 in NIH Stroke Scale. Multi-variate analysis was performed.

RESULTS

There were 43 patients with a mean age of 77 ± 13 years with primarily mild TBI (95%) after a ground level fall (79%). The mean dose was 41 ± 12 units/kg. Sixty percent received 4 F-PCC and 40% APCC. The incidence of treatment failure was 28% (12/43). Of the 12 patients with hematoma expansion, only 3 were symptomatic (9.3%). Hematoma expansion with 4 F-PCC and APCC were similar (27% vs. 29%,p = .859). Only sex was associated with hematoma expansion on multivariate analysis [OR (95% CI) = 6.7 (1.1 - 40.9)].

CONCLUSION

PCC was an effective option for factor Xa inhibitor reversal following TBI. The relationship between radiographic expansion and clinical expansion was poor.

Current Evidence and Expert Opinion on Thromboprophylaxis After Total Knee and Hip Replacement

An effective anticoagulant provides a balance between the risk for venous thromboembolism (VTE) and bleeding and is crucial in achieving optimal clinical outcomes in patients undergoing total hip replacement (THR) and total knee replacement (TKR) surgeries. We performed a review of the literature on thromboprophylaxis for patients undergoing total hip or knee replacement. This review article summarizes current guidelines and evidence for anticoagulation along with the expert opinion about pharmacological VTE prophylaxis, particularly non-Vitamin K antagonist oral anticoagulants (NOACs), for patients after total hip or knee replacement. Aspirin for VTE prophylaxis after TKR/THR has been controversial and most of the evidence is reported from observational research. Although the guidelines do not recommend any specific thromboprophylaxis agent, available evidence suggests that NOACs are as effective as low molecular weight heparins (LMWHs) in preventing VTE. Oral administration and the lack of dose monitoring make NOACs easy to use in outpatient settings in cases with challenging treatment compliances. They can be used for two weeks after TKR and five weeks after THR - six weeks after TKR and THR to cover the at-risk period for VTE post-discharge. Owing to the lack of evidence for a head-to-head comparison of NOACs, an anticoagulant with better efficacy and safety may be suggested in special patient populations (elderly, obese patients, or those with renal dysfunction). The expert opinion on pharmacological VTE prophylaxis provided in this article could address some gaps in the management of anticoagulation in patients with total hip or knee replacement.