Practical Management of Anticoagulation in Patients With Atrial Fibrillation

NF2-Related Schwannomatosis (NF2): Molecular Insights and Therapeutic Avenues

NF2-related schwannomatosis (NF2) is a genetic syndrome characterized by the growth of benign tumors in the nervous system, particularly bilateral vestibular schwannomas, meningiomas, and ependymomas. This review consolidates the current knowledge on NF2 syndrome, emphasizing the molecular pathology associated with the mutations in the gene of the same name, the NF2 gene, and the subsequent dysfunction of its product, the Merlin protein. Merlin, a tumor suppressor, integrates multiple signaling pathways that regulate cell contact, proliferation, and motility, thereby influencing tumor growth. The loss of Merlin disrupts these pathways, leading to tumorigenesis. We discuss the roles of another two proteins potentially associated with NF2 deficiency as well as Merlin: Yes-associated protein 1 (YAP), which may promote tumor growth, and Raf kinase inhibitory protein (RKIP), which appears to suppress tumor development. Additionally, this review discusses the efficacy of various treatments, such as molecular therapies that target specific pathways or inhibit neomorphic protein-protein interaction caused by NF2 deficiency. This overview not only expands on the fundamental understanding of NF2 pathophysiology but also explores the potential of novel therapeutic targets that affect the clinical approach to NF2 syndrome.

[Preoperative evaluation of adult patients before elective, non-cardiothoracic surgery : A joint recommendation of the German Society for Anesthesiology and Intensive Care Medicine, the German Society for Surgery and the German Society for Internal Medicine]

The 70 recommendations summarize the current status of preoperative risk evaluation of adult patients prior to elective non-cardiothoracic surgery. Based on the joint publications of the German scientific societies for anesthesiology and intensive care medicine (DGAI), surgery (DGCH), and internal medicine (DGIM), which were first published in 2010 and updated in 2017, as well as the European guideline on preoperative cardiac risk evaluation published in 2022, a comprehensive re-evaluation of the recommendation takes place, taking into account new findings, the current literature, and current guidelines of international professional societies. The revised multidisciplinary recommendation is intended to facilitate a structured and common approach to the preoperative evaluation of patients. The aim is to ensure individualized preparation for the patient prior to surgery and thus to increase patient safety. Taking into account intervention- and patient-specific factors, which are indispensable in the preoperative risk evaluation, the perioperative risk for the patient should be minimized and safety increased. The recommendations for action are summarized under "General Principles (A)," "Advanced Diagnostics (B)," and the "Preoperative Management of Continuous Medication (C)." For the first time, a rating of the individual measures with regard to their clinical relevance has been given in the present recommendation. A joint and transparent agreement is intended to ensure a high level of patient orientation while avoiding unnecessary preliminary examinations, to shorten preoperative examination procedures, and ultimately to save costs. The joint recommendation of DGAI, DGCH and DGIM reflects the current state of knowledge as well as the opinion of experts. The recommendation does not replace the individualized decision between patient and physician about the best preoperative strategy and treatment.

Comparative Effectiveness and Safety of Direct Oral Anticoagulants in Low Body Weight Patients with Atrial Fibrillation: A Systematic Review and Meta-analysis

INTRODUCTION

Direct oral anticoagulant (DOAC) agents are established as the anticoagulation strategy of choice for a variety of clinical risks. Despite this, uncertainty still exists with regard to their efficacy and safety for the prevention of stroke and systemic embolism in some patient populations; most notably those with low body weight (LBW) (<60 kg or body mass index [BMI] <18 kg/m2). Currently, there is a paucity of trial and non-trial data to support a prescriptive recommendation for their use in these patient cohorts. We have carried out a pooled systematic review of the most up to date published data of patients stabilized on various DOAC analogs with the view to ascertaining the exact matrices of their efficacy and safety in these cohorts of patients.

METHODS

We initially carried out a comprehensive search of databases from inception to June 2023 for eligible studies exploring the efficacy and safety of various analogs of direct oral anticoagulants in patients with atrial fibrillation who had low body weight. Databases accessed include PubMed, EMBASE, the Science Citation Index, the Cochrane Database of Systematic Reviews, and the Database of Abstracts of Reviews of Effectiveness. We carried out a weighted comparison of derived pooled odd ratios (with their corresponding confidence intervals) of mortality outcomes between various DOACs using the random effects model.

RESULTS

Thirteen studies (n = 165,205 patients) were included in our meta-analysis. DOAC analogs were associated with increased stroke-related events, composite outcome, and mortality in low body weight patients compared to non-low body weight patients (odds ratio [OR] 1.50, 95% confidence interval [CI] 1.17-1.92), (OR 1.55, 95% CI 1.29-1.86), (OR 2.92, 95% CI 1.87-4.58), respectively. There was no significant difference in the safety outcome (major bleeding events) between the DOAC analogs (OR 1.19, 95% CI 0.93-1.52).

DISCUSSION

In this meta-analytical review comprising both real-world and randomized controlled studies, the use of DOAC analogs in low body weight patients (body weight of <60 kg or BMI<18 kg/m2) with atrial fibrillation was associated with increased risks of stroke-related events, composite outcomes, and mortality compared to non-low body weight cohorts patients. At the same time, there was no significant difference in terms of major bleeding events. This finding has provided the first resolution of pervading uncertainty surrounding the use of DOAC analogs in these patient cohorts and suggests the need for follow-up confirmatory systematic studies in this group of patients.

Management of Antithrombotic Drugs before Elective Spine Surgery: A Nationwide Web-Based Questionnaire Survey in Japan

Introduction

The number of patients on antithrombotic drugs for coronary heart disease or cerebrovascular disease has been increasing with the aging of society. We occasionally need to decide whether to continue or discontinue antithrombotic drugs before spine surgery. The purpose of this study is to understand the current perioperative management of antithrombotic drugs before elective spine surgery in Japan.

Methods

In 2021, members of the Japanese Society for Spine Surgery and Related Research (JSSR) were asked to complete a web-based questionnaire survey that included items concerning the respondents' surgical experience, their policy regarding discontinuation or continuation of antithrombotic drugs, their reasons for decisions concerning the management of antithrombotic drugs, and their experience of perioperative complications related to the continuation or discontinuation of these drugs.

Results

A total of 1,181 spine surgeons returned completed questionnaires, giving a response rate of 32.0%. JSSR board-certified spine surgeons comprised 75.1% of the respondents. Depending on the management policy regarding antithrombotic drugs for each comorbidity, approximately 73% of respondents discontinued these drugs before elective spine surgery, and about 80% also discontinued anticoagulants. Only 4%-5% of respondents reported continuing antiplatelet drugs, and 2.5% reported continuing anticoagulants. Among the respondents who discontinued antiplatelet drugs, 20.4% reported having encountered cerebral infarction and 3.7% reported encountering myocardial infarction; among those who discontinued anticoagulants, 13.6% reported encountering cerebral embolism and 5.4% reported encountering pulmonary embolism. However, among the respondents who continued antiplatelet drugs and those who continued anticoagulants, 26.3% and 27.2%, respectively, encountered an unexpected increase in intraoperative bleeding, and 10.3% and 8.7%, respectively, encountered postoperative spinal epidural hematoma requiring emergency surgery.

Conclusions

Our findings indicate that, in principle, >70% of JSSR members discontinue antithrombotic drugs before elective spine surgery. However, those with a discontinuation policy have encountered thrombotic complications, while those with a continuation policy have encountered hemorrhagic complications.

[Targeting anticoagulated patients for medication reconciliation at discharge in orthopaedic surgery]

In orthopedic surgery, the well-known iatrogenic risk of oral anticoagulants is particularly increased due to surgical management (suspension and resumption of treatment). In order to prevent avoidable iatrogenic events linked to incomplete discharge documents, targeted medical reconciliation (MR) has been deployed. This is a single-center prospective study conducted in orthopaedic surgery for six months including any patient treated upon admission with an oral anticoagulant. The analysis of the compliance of discharge documents (hospitalization report and prescriptions) was carried out before and after pharmaceutical interventions. The criteria analysed included the mention of the oral treatment, its dosage as well as the supervision of the switch from heparin therapy to the usual oral treatment. The documents were compliant if the mention of oral anticoagulant treatment and the date of the shift were correctly documented. Thirty-seven patients were included. The compliance rate of discharge documents was significantly improved by MR, going from 13.5 % to 78.4 % (P <0.05). The non-compliances before the intervention concerned the absence of mention of: the usual treatment (64.9 %), its dosage (81.1 %) or the switch's securing (75.7 %). Discharge from surgery of the patient on anticoagulants is a stage presenting a real risk which can be managed by the intervention of pharmacists. Improving the compliance of discharge documents is a first step towards better securing drug management.

Comparison of Patient Outcomes Before and After Switching From Warfarin to a Direct Oral Anticoagulant Based on Time in Therapeutic Range Guideline Recommendations

This cohort study evaluates stroke and major bleeding rates before and after switching from warfarin to a direct oral anticoagulant (DOAC) in patients grouped by pre-switch time-in-therapeutic range guideline thresholds.

Rationale and design of a prospective study evaluating population pharmacokinetics and pharmacodynamics of rivaroxaban in Chinese patients with non-valvular atrial fibrillation

INTRODUCTION

Rivaroxaban is one of the most commonly used non-vitamin K antagonists for stroke prevention in patients with non-valvular atrial fibrillation (NVAF). Different individual exposures exist for Asian and non-Asian populations, and dose selection is different for Japanese and non-Japanese subjects. Few studies have investigated the pharmacokinetics (PK) and pharmacodynamics (PD) of rivaroxaban in Chinese patients and provided a solid reference for dose selection and individualised therapy.

METHODS AND ANALYSIS

This is a single-centre prospective study. Rivaroxaban-treated Chinese NVAF patients will be recruited according to predetermined inclusion criteria. Blood samples will be collected from both outpatients and inpatients with different sampling strategies at steady state. Rivaroxaban plasma concentration, factor Xa activity, prothrombin time and single-nucleotide polymorphisms of candidate genes will be evaluated. Follow-up will be conducted following 3 and 6 months after enrolment to collect information about the safety and efficacy outcomes. A nonlinear mixed-effects modelling strategy will be used to develop a population PK-PD model of rivaroxaban.

ETHICS AND DISSEMINATION

The study has been approved by the Ethics Committee of Huashan Hospital, Fudan University (KY2020-016). The study findings will be submitted to peer-reviewed journals and shared with public health authorities.

TRIAL REGISTRATION NUMBER

ChiCTR2100046685.

Cutaneous Ulcer Caused by Apixaban Treatment Is Resolved after Replacement with Dabigatran

Nowadays, novel oral anticoagulants (NOACs) have shown improved safety profile and efficacy compared to vitamin K antagonists in the prevention of thromboembolic events occurring during different pathological conditions. However, there are concerns and safety issues, mostly related to adverse events following interactions with other drugs, in real-world practice. We report the case of an 83-year-old woman who developed a non-bleeding leg ulcer not caused by trauma or other evident pathological conditions after 10 days of treatment with apixaban 5 mg/q.d. She was switched from apixaban to dabigatran and the leg ulcer rapidly improved and completely cicatrized in 40 days. The resolution of the ulcer and the toleration of dabigatran therapy suggest an apixaban-specific reaction; however, the pathological mechanism of ulcer onset is currently unclear. Careful evaluation of hospital databases of Molise region (Southern Italy) hospitals identified two similar cases between 2019 and 2021. These cases underline the necessity of careful post-marketing surveillance, considering the rapidly increasing number of patients treated with NOACs and patient’s risk factors such as old age, high polypharmacy rate, co-morbidities, and peculiar genetic background related to NOACs pharmacokinetic features.

Perioperative Anticoagulation Management

Management of anticoagulation in individuals undergoing operative procedures is a complex situation. Each case should be assessed individually with proper risk assessment, monitoring, and plan for perioperative and postoperative anticoagulation. Clinical evidence for the management of these patients is relatively scarce, and clinicians are often assessing each individual case with minimal guidance. This review provides nurses with a summary of available literature on the assessment, laboratory monitoring, timing of adjusting anticoagulation, and bridging prior to procedures. In addition to general perioperative anticoagulation management, this review discusses perioperative management in special populations and provides a summary on principles when anticoagulation should be resumed following a procedure.

Association Between Apelin and Atrial Fibrillation in Patients With High Risk of Ischemic Stroke

Background: Atrial fibrillation (AF) is associated with high risk of stroke preventable by timely initiation of anticoagulation. Currently available screening tools based on ECG are not optimal due to inconvenience and high costs. Aim of this study was to study the diagnostic value of apelin for AF in patients with high risk of stroke.

Methods: We designed a multicenter, matched-cohort study. The population consisted of three study groups: a healthy control group (34 patients) and two matched groups of 60 patients with high risk of stroke (AF and non-AF group). Apelin levels were examined from peripheral blood.

Results: Apelin was significantly lower in AF group compared to non-AF group (0.694 ± 0.148 vs. 0.975 ± 0.458 ng/ml, p = 0.001) and control group (0.982 ± 0.060 ng/ml, p < 0.001), respectively. Receiver operating characteristic (ROC) analysis of apelin as a predictor of AF scored area under the curve (AUC) of 0.658. Apelin's concentration of 0.969 [ng/ml] had sensitivity = 0.966 and specificity = 0.467. Logistic regression based on manual feature selection showed that only apelin and NT-proBNP were independent predictors of AF. Logistic regression based on selection from bivariate analysis showed that only apelin was an independent predictor of AF. A logistic regression model using repeated stratified K-Fold cross-validation strategy scored an AUC of 0.725 ± 0.131.

Conclusions: Our results suggest that apelin might be used to rule out AF in patients with high risk of stroke.

Analysis of Direct Oral Anticoagulant Therapy With Concomitant Use of Interacting Antiretroviral Agents

Background: A theoretical interaction exists between human immunodeficiency virus (HIV) antiretroviral (ARV) agents and direct oral anticoagulants (DOACs), although the clinical significance is unclear. Objective: This study aimed to assess characteristics, prescribing patterns, and outcomes associated with concomitant therapy. Methods: A single-center, retrospective review was performed on patients older than 18 years prescribed a DOAC for any indication with concurrent interacting ARV(s) from June 2016 through June 2019. The primary endpoint was to assess prescribing and population characteristics. Secondary endpoints were to evaluate safety outcomes, DOAC level monitoring, readmissions, outpatient follow-up, and DOAC modification interventions. Results: Thirty-six patients (72 hospital admissions) were identified. The most common DOAC was apixaban (83.3%) and ARV was ritonavir (50%). Of the 72 encounters, 26 (36.1%) DOACs were dosed appropriately per guideline recommendations. Twenty pharmacy interventions for therapy modification were recognized. Eleven (30.6%) patients experienced bleeding and 2 (5.6%) thrombosis. Of the adverse events, all patients had renal impairment. Conclusions: As DOAC utilization grows, increasing use in HIV could be expected. More frequent adjustment or avoidance is recommended per guidelines. Our data suggest the majority of patients receive CYP3A4-inhibiting regimens. Caution should be employed with renal insufficiencies. Further studies are warranted to assess safety and efficacy within this population.

Determinants for under- and overdosing of direct oral anticoagulants and physicians' implementation of clinical pharmacists' recommendations

AIMS

To analyse the appropriateness of direct oral anticoagulant (DOAC) dosing and determinants for under-and overdosing as well as acceptance and implementation rates of pharmacists' interventions.

METHODS

Cross-sectional study in a tertiary hospital in hospitalized patients with atrial fibrillation on DOACs in 2019 (n = 1688). Primary outcome was the proportion of patients with inappropriate DOAC prescribing with identification of determinants for under-and overdosing. Secondary outcomes included acceptance and implementation rates of pharmacists' recommendations and determination of reasons for nonacceptance/nonimplementation.

RESULTS

Inappropriate prescribing was observed in 16.9% of patients (n = 286) with underdosing (9.7%) being more prevalent than overdosing (6.9%). For all DOACs considered together, body weight<60 kg (odds ratio [OR] 0.46 [0.27-0.77]), edoxaban use (OR 0.42 [0.24-0.74]), undergoing surgery (OR 0.57 [0.37-0.87]) and being DOAC naïve (OR 0.45 [0.29-0.71]) were associated with significantly lower odds of underdosing. Bleeding history (OR 1.86 [1.24-2.80]) and narcotic use (OR 1.67 [1.13-2.46]) were associated with significantly higher odds for underdosing. Determinants with a significantly higher odds of overdosing were renal impairment (OR 11.29 [6.23-20.45]) and body weight<60 kg (OR 2.34 [1.42-3.85]), whereas dabigatran use (OR 0.24 [0.08-0.71]) and apixaban (OR 0.18 [0.10-0.32]) were associated with a significantly lower odds of overdosing compared to rivaroxaban. Physicians accepted the pharmacists' advice in 179 cases (79.2%) consisting of 92 (51.4%) recommendations for underdosing, 82 (45.8%) for overdosing and 5 (2.8%) for contraindications.

CONCLUSION

Inappropriate DOAC prescribing remains common, although there is a slight improvement compared to our study of 2016. Clinical services led by pharmacists help physicians to reduce the number of inadequate prescriptions for high-risk medications such as DOACs.

Assessment of Oral Anticoagulant Adverse Drug Events Before and After Implementation of a Real-Time Clinical Surveillance Tool

OBJECTIVE

The aim of the study was to determine the effect on occurrence of oral anticoagulant adverse drug events (ADEs) after implementation of a real-time clinical surveillance tool in a large health system.

METHODS

Records of patients receiving an oral anticoagulant during a 6-month period before and after implementation of a real-time clinical surveillance tool were reviewed for 31 hospitals within a nationwide health system. The real-time clinical surveillance tool analyzed clinical data from the electronic medical record and alerted the pharmacist of potential opportunities for patient clinical intervention. Oral anticoagulant administration data, International Classification of Diseases, Ninth Edition code documentation of ADEs caused by oral anticoagulants, and alert notification data from the real-time clinical surveillance tool were evaluated.

RESULTS

A total of 56,761 patients were included in the study. The oral anticoagulant ADE ratio decreased from 0.69% during the period before implementation of the real-time clinical surveillance tool to 0.41% during the period after implementation (P < 0.001). Most alert notifications and greatest impact on ADE ratio occurred in patients administered a single oral anticoagulant during hospitalization.

CONCLUSIONS

Implementation of a real-time clinical surveillance tool prompting pharmacist intervention reduced the oral anticoagulant ADE ratio for the health system.

Quality of life in patients with nonvalvular atrial fibrillation treated with oral anticoagulants

OBJECTIVES

Health-related quality of life (HRQL) is a key factor in making anticoagulant treatment decisions. The objective of this study was to assess the HRQL of patients with nonvalvular atrial fibrillation by treatment type: direct oral anticoagulants (DOACs) or vitamin K antagonists (VKAs).

METHODS

We carried out a cross-sectional observational study with clinical practice data, gathering demographic and clinical variables. HRQL was measured using the 5-level 5-dimension EuroQol questionnaire (EQ-5D-5L). Differences between the study groups in HRQL as measured by the EQ-5D-5L were analyzed using two-part multivariate regression models. First, using logistic regression, the adjusted probability, p(x), of having perfect health was estimated in each subgroup. Secondly, generalized linear models were used to estimate mean disutility values, w(x), in a population that does not have perfect health, i.e. utility less than 1 or 1-w(x).

RESULTS

We recruited 333 patients, of whom 126 were on DOACs and 207 on VKAs. A significant difference was observed in the EQ-5D-5L anxiety/depression dimension, with a higher percentage of patients classified in the 'no problems' category in the DOAC group. The same type of analysis did not identify significant differences in any of the other dimensions (mobility, self-care, usual activities or pain/discomfort).

DISCUSSION

In the multivariate model, utility was significantly higher in the DOAC group than in the VKA group, although the difference was small (0.0121). This difference is attributable to patients on DOACs having less anxiety/depression.

CONCLUSION

Patients treated with DOACs report a slightly better quality of life than those treated with VKAs.

Thromboembolism in Older Adults

Arterial and venous thromboembolism are both more common in older adults. The use of anticoagulants, the mainstay to prevent thromboembolism, requires consideration of the balance between risk and benefit. Such consideration is even more important in the very elderly in whom the risk of anticoagulant-related bleeding and thrombosis are higher. This review will focus on the challenges of implementing and managing anticoagulant therapy in older patients in an era when the options for anticoagulants include not only vitamin K antagonists (VKAs), but also direct-acting oral anticoagulants (DOACs).

Development of an Institutional Periprocedural Management Guideline for Oral Anticoagulants

Patients on oral anticoagulation commonly undergo surgery or other invasive procedures. Periprocedural management of oral anticoagulants involves a careful balance of the thromboembolic risk and bleeding risk. To standardize clinical practice at our institution, we developed a guideline for periprocedural management for patients taking oral anticoagulants that incorporates published data and expert opinion. In this article, we present our clinical practice guideline as a decision support tool to aid clinicians in developing a consistent strategy for managing periprocedural anticoagulation and for safely bridging anticoagulation in patients who require it.

Association between platelet count and the risk of bleeding among patients with nonvalvular atrial fibrillation taking dabigatran after radiofrequency ablation: a cohort study

Background

A reduction in platelet count or function can be a risk factor for bleeding in anticoagulated patients. However, the association between platelet count and the risk of bleeding among nonvalvular atrial fibrillation (NVAF) patients taking dabigatran remains unclear. The aim of this study was to investigate the relationship between platelet count and the risk of bleeding among patients with NVAF taking dabigatran after radiofrequency ablation.

Methods

In this multicenter, prospective and observational study, a total of 576 NVAF patients treated with dabigatran (110 mg bid) after radiofrequency ablation were recruited from 12 centers in China from February 2015 to December 2017. All patients were followed for 3 months. The association between platelet count and the risk of bleeding was evaluated by Cox proportional hazards regression analysis. To explore the nonlinearity between platelet count and bleeding, we used a Cox proportional hazards regression model with cubic spline functions and smooth curve fitting and a two-piecewise Cox proportional hazards model.

Results

During a median follow-up duration of 87 days, 50 patients experienced bleeding events. Overall, there was an inverse relationship between the risk of bleeding and platelet count. Low platelet count (<100×10⁹/L) were associated with an increased risk of bleeding [hazard ratio (HR), 4.05; 95% confidence interval (CI): 1.32-12.46] compared to normal counts. The adjusted smooth curve showed a nonlinear relationship between platelet count and bleeding events. The inflection point of the platelet count was 105×10⁹/L. For platelet counts <105×10⁹/L, the HR (95% CI) was 0.89 (0.84-0.95), and for platelet counts ≥105×10⁹/L, the HR (95% CI) was 1.01 (0.95-1.08).

Conclusions

Low platelet counts were associated with an increased risk for bleeding among patients with NVAF taking dabigatran after catheter ablation.

Efficacy and safety of ShenSongYangXin Capsule combined with antiarrhythmic drugs for atrial fibrillation: A protocol for systematic review and network meta-analysis

BACKGROUND

Shen-Song-Yang-Xin Capsule (SSYX), a Chinese patent medicine, combined with antiarrhythmic drugs (AADs) in the treatment of atrial fibrillation (AF) has been widely applied in clinical practice, but the results are controversial. This study aims to conduct a network meta-analysis (NMA) based on data from the randomized controlled trials (RCTs) to evaluate the efficacy and safety of SSYX combined with ADDs in the treatment of AF.

METHODS AND ANALYSIS

A comprehensive systematic literature search will be conducted in Cochrane Library, PubMed, Web of Science, EMBASE, Chinese Biomedical Literature Database (SinoMed), Chinese National Knowledge Infrastructure (CNKI), and WanFang database for RCTs about SSYX combined with ADDs. The primary outcomes will be the frequency of AF attack and P-wave dispersion, and the secondary outcomes will be the symptom improvements, left atrial diameter, and adverse events. Statistical analyses will be conducted by using WinBUGS software (version 1.4.3), Stata software (version 14.0) and RevMan software (version 5.3).

RESULTS

The results of this NMA will provide a high-quality evidence for the efficacy of SSYX combined with ADDs in the treatment of AF, and a ranking of the therapeutic classes will also be presented.

CONCLUSION

The protocol will provide updated evidence for the application of SSYX for AF. INTERNATIONAL PLATFORM OF REGISTERED SYSTEMATIC REVIEW AND META-ANALYSIS PROTOCOLS (INPLASY) REGISTRATION NUMBER:: The protocol of this systematic review and meta-analysis was registered on the INPLASY website (https://inplasy.com/inplasy-2020-8-0075/) and INPLASY registration number is INPLASY202080075.

Appropriate Dosing Regimens of Non-Vitamin K Antagonist Oral Anticoagulants for Treatment of Patients With Non-Valvular Atrial Fibrillation: An Evidence-Based Consideration

Patients with non-valvular atrial fibrillation (NVAF) exhibit a high risk of stroke, which is associated with high mortality. Thus, stroke prevention is crucial for the overall management of NVAF. Two categories of drugs, vitamin K antagonist warfarin and non-vitamin K antagonist oral anticoagulants (NOACs), are clinically used to prevent NVAF-related stroke. In some circumstances, NOACs are superior to warfarin. However, NOACs selection for NVAF patients is affected by many factors, including individual patient characteristics, comorbidities, risk factors, or laboratory variables. This article summarizes the discrepancy in NOACs management with emphasis on the dosing regimens and influencing factors, such as stroke risk, age, body weight, renal function, gastrointestinal bleeding (GIB) risk, and combination of antiplatelet therapy, in order to identify individual groups with particular clinical characteristics who may obtain more benefit from a certain dosing regimen of NOACs. Determination of a particular subset of patient populations for the appropriate dose regimen of NOACs will help to achieve desired clinical outcomes. Furthermore, to compensate clinical evidence, we should place more emphasis on the findings of current clinical trials and supplement real-world data.

Association Between the Change in Total Bilirubin and Risk of Bleeding Among Patients With Nonvalvular Atrial Fibrillation Taking Dabigatran

There is still a lack of effective biomarkers for the prediction of the risk of bleeding events among patients with nonvalvular atrial fibrillation (NVAF) taking dabigatran. This study aimed to investigate the association between change in total bilirubin (CTBIL) and risk of bleeding among patients with NVAF taking dabigatran. The CTBIL was the difference in serum total bilirubin at out of follow-up from baseline serum total bilirubin. A total of 486 patients with NVAF treated with dabigatran (110 mg twice daily) were recruited from 12 centers in China from February 2015 to December 2017. All patients were followed for 3 months. Cox proportional hazards regression analysis was used to evaluate the association between the CTBIL and bleeding. Moreover, a Cox proportional hazards regression with cubic spline functions and smooth curve fitting (the penalized spline method) and 2 piecewise Cox proportional hazards models were used to address the nonlinearity between CTBIL and bleeding. The mean (SD) follow-up duration was 81.2 (20.2) days. In all, 67 patients experienced bleeding events. A U-shaped association was observed between the CTBIL and bleeding, with increased hazard ratios (HRs) in relation to either low or high CTBIL levels. For CTBIL <6.63 µmol/L, the HR (95% confidence interval [CI]) was 0.90 (0.84-0.96), and for CTBIL ≥6.63 µmol/L, the HR (95% CI) was 1.35 (1.14-1.60). Our findings showed a U-shaped relationship between CTBIL and bleeding. Both low and high levels of CTBIL were associated with a higher risk of bleeding.

Direct Oral Anticoagulants in Patients With Nonvalvular Atrial Fibrillation: Update and Periprocedural Management

Vitamin K antagonists (eg, warfarin) have been the standard of care for stroke prophylaxis in atrial fibrillation. The direct oral anticoagulants dabigatran (direct thrombin inhibitor) and rivaroxaban, apixaban, and edoxaban (direct factor Xa inhibitors) are as efficacious as and in some instances superior to vitamin K antagonists in the prevention of stroke, systemic embolism, and major bleeding compared with warfarin for nonvalvular atrial fibrillation. Benefits of direct oral anticoagulants include a rapid onset of therapeutic effect, fixed dose-response relationships without the need for routine monitoring, a short half-life, and infrequent need for periprocedural bridging with a parenteral agent. However, direct oral anticoagulants differ in subsets of patients. Critical care and advanced practice nurses must understand these differences, prescribing considerations, drug aherence interventions, drug-drug interactions, and periprocedural management. This article presents an update and review of direct oral antigcoagulants based on the latest national guidelines.

Management of Severe Bleeding in Patients Treated With Oral Anticoagulants: Proceedings Monograph From the Emergency Medicine Cardiac Research and Education Group-International Multidisciplinary Severe Bleeding Consensus Panel October 20, 2018

In this Emergency Medicine Cardiac Research and Education Group (EMCREG)-International Proceedings Monograph from the October 20, 2018, EMCREG-International Multidisciplinary Consensus Panel on Management of Severe Bleeding in Patients Treated With Oral Anticoagulants held in Orlando, FL, you will find a detailed discussion regarding the treatment of patients requiring anticoagulation and the reversal of anticoagulation for patients with severe bleeding. For emergency physicians, critical care physicians, hospitalists, cardiologists, internists, surgeons, and family physicians, the current approach and disease indications for treatment with anticoagulants such as coumadin, factor IIa, and factor Xa inhibitors are particularly relevant. When a patient treated with anticoagulants presents to the emergency department, intensive care unit, or operating room with severe, uncontrollable bleeding, achieving rapid, controlled hemostasis is critically important to save the patient's life. This EMCREG-International Proceedings Monograph contains multiple sections reflecting critical input from experts in Emergency Cardiovascular Care, Prehospital Emergency Medical Services, Emergency Medicine Operations, Hematology, Hospital Medicine, Neurocritical Care, Cardiovascular Critical Care, Cardiac Electrophysiology, Cardiology, Trauma and Acute Care Surgery, and Pharmacy. The first section provides a description of the current indications for the treatment of patients using oral anticoagulants including coumadin, the factor IIa (thrombin) inhibitor dabigatran, and factor Xa inhibitors such as apixaban and rivaroxaban. In the remaining sections, the treatment of patients presenting to the hospital with major bleeding becomes the focus. The replacement of blood components including red blood cells, platelets, and clotting factors is the critically important initial treatment for these individuals. Reversing the anticoagulated state is also necessary. For patients treated with coumadin, infusion of vitamin K helps to initiate the process of protein synthesis for the vitamin K-dependent coagulation proteins II, VII, IX, and X and the antithrombotic protein C and protein S. Repletion of clotting factors for the patient with 4-factor prothrombin complex concentrate, which includes factors II (prothrombin), VII, IX, and X and therapeutically effective concentrations of the regulatory proteins (protein C and S), provides real-time ability to slow bleeding. For patients treated with the thrombin inhibitor dabigatran, treatment using the highly specific, antibody-derived idarucizumab has been demonstrated to reverse the hypocoagulable state of the patient to allow blood clotting. In May 2018, andexanet alfa was approved by the US Food and Drug Administration to reverse the factor Xa anticoagulants apixaban and rivaroxaban in patients with major bleeding. Before the availability of this highly specific agent, therapy for patients treated with factor Xa inhibitors presenting with severe bleeding usually included replacement of lost blood components including red blood cells, platelets, and clotting factors and 4-factor prothrombin complex concentrate, or if not available, fresh frozen plasma. The evaluation and treatment of the patient with severe bleeding as a complication of oral anticoagulant therapy are discussed from the viewpoint of the emergency physician, neurocritical and cardiovascular critical care intensivist, hematologist, trauma and acute care surgeon, hospitalist, cardiologist, electrophysiologist, and pharmacist in an approach we hope that the reader will find extremely practical and clinically useful. The clinician learner will also find the discussion of the resumption of oral anticoagulation for the patient with severe bleeding after effective treatment important because returning the patient to an anticoagulated state as soon as feasible and safe prevents thrombotic complications. Finally, an EMCREG-International Severe Bleeding Consensus Panel algorithm for the approach to management of patients with life-threatening oral anticoagulant-associated bleeding is provided for the clinician and can be expanded in size for use in a treatment area such as the emergency department or critical care unit.

Oral Anticoagulation in Patients With Liver Disease

Patients with liver disease are at increased risks of both thrombotic and bleeding complications. Many have atrial fibrillation (AF) or venous thromboembolism (VTE) necessitating oral anticoagulant agents (OACs). Recent evidence has contradicted the assumption that patients with liver disease are "auto-anticoagulated" and thus protected from thrombotic events. Warfarin and non-vitamin K-antagonist OACs have been shown to reduce thrombotic events safely in patients with either AF or VTE. However, patients with liver disease have largely been excluded from trials of OACs. Because all currently approved OACs undergo metabolism in the liver, hepatic dysfunction may cause increased bleeding. Thus, the optimal anticoagulation strategy for patients with AF or VTE who have liver disease remains unclear. This review discusses pharmacokinetic and clinical studies evaluating the efficacy and safety of OACs in patients with liver disease and provides a practical, clinically oriented approach to the management of OAC therapy in this population.

Reversal agents for direct oral anticoagulants: considerations for hospital physicians and intensivists

Direct oral anticoagulants (DOACs) include dabigatran etexilate, a direct thrombin inhibitor, and specific inhibitors of activated coagulation factor X (FXa; e.g. apixaban, betrixaban, edoxaban, rivaroxaban). DOACs are associated with lower rates of major and fatal bleeding events compared with warfarin. Clinicians may need to achieve rapid reversal of anticoagulation effects of the DOACs in an emergency setting. Idarucizumab and andexanet alfa, which reverse the anticoagulant effects of dabigatran and FXa inhibitors, respectively, are DOAC reversal agents available in the US. Other reversal agents (e.g. ciraparantag for heparins, DOACs) are in development. Alternative nonspecific agents (e.g. fresh frozen plasma, prothrombin complex concentrate) are available. Nonspecific prohemostatic agents can counteract the anticoagulant action of DOACs in emergency situations, when specific reversal agents are unavailable. However, specific reversal agents are efficacious and safe and should be preferred when available. In this review, we discuss practical issues in the initiation of DOAC therapy, situations where reversal may be needed, coagulation assays, reversal agents, and post-reversal complications in the context of published evidence and guidelines.

Features of Thromboembolic and Hemorrhagic Complications in Planned Surgical Interventions in Patients with Atrial Fibrillation

Aim. To study the frequency and characteristics of the development of thromboembolic and hemorrhagic complications in patients with atrial fibrillation (AF) during planned surgical interventions.Material and methods. Preoperative examination and postoperative observation of 214 patients with AF (139 men and 75 women) who received anticoagulant therapy (ACT) and underwent planned surgery was carried out. The consistency of the used perioperative ACT regimens when performing interventions with current international recommendations was analyzed.Results. Complications developed in 33 patients (15.4%) from the total sample of 214 patients: in 14 (6.5%) thromboembolism, in 19 (8.9%) hemorrhagic complications. Analysis of the complication frequency in various types of surgical interventions showed that the frequency of thromboembolism during heart and vascular operations was 9.8% (4 cases), with interventions for malignant tumors – 7 (6.2%), while performing general surgical abdominal tumors operations – 3 (5.0%). The frequency of bleeding was maximum during operations for cancer 18.6%, this value was significantly higher compared with the frequency of these complications when performing general surgical abdominal operations – 3 cases (5.0%), and during interventions on the heart and vascular vessels bleedings were not observed. The total frequency of complications was also maximal when performing interventions for malignant tumors – 24.8%. This value was significantly higher than in the groups of patients who underwent general surgical abdominal operations – 10.0%, and interventions on the heart and vessels – 9.8%. Analysis of the frequency of compliance with the recommendations of the European Society of Cardiology in terms of ACT usage in patients with AF in the perioperative period and the structure of errors in choosing the ACT regimen showed that among the examined patients the recommendations were followed only in 102 (47.7%), while the frequency of non-recommended regimens use reached 52.3% (112 patients). The most frequently incorrectly used scheme was “bridge therapy” with the possibility of canceling oral anticoagulants in 107 (50.0%) patients.Conclusion. A significantly higher frequency of complications was found in patients, whose management did not follow the recommendations for perioperative ACT.

Antithrombotics: From Aspirin to DOACs in Coronary Artery Disease and Atrial Fibrillation (Part 3/5)

For secondary prevention of coronary artery disease (CAD), oral antiplatelet therapy is essential. In case of coronary intervention, temporary dual antiplatelet therapy is mandatory as well. Recently, low-dose oral anticoagulation has entered the CAD arena. Atrial fibrillation (AF) is often seen in CAD and vice versa. In most patients stroke prevention in AF consists of oral anticoagulation. In many cases of CAD in patients with AF, anticoagulation has to be combined with antiplatelet agents (so called, dual pathway antithrombotic therapy). Excess bleeding in these conditions is a rapidly rising problem. This review addresses the antithrombotic options in CAD alone, in AF alone, and in their combination, when either an invasive or a noninvasive approach has been chosen.

Economic Analysis of Apixaban Therapy for Patients With Atrial Fibrillation From a US Perspective: Results From the ARISTOTLE Randomized Clinical Trial

Importance

The Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial reported that apixaban therapy was superior to warfarin therapy in preventing stroke and all-cause death while causing significantly fewer major bleeds. To establish the value proposition of substituting apixiban therapy for warfarin therapy in patients with atrial fibrillation, we performed a cost-effectiveness analysis using patient-level data from the ARISTOTLE trial.

Objective

To assess the cost and cost-effectiveness of apixaban therapy compared with warfarin therapy in patients with atrial fibrillation from the perspective of the US health care system.

Design, Setting, and Participants

This economic analysis uses patient-level resource use and clinical data collected in the ARISTOTLE trial, a multinational randomized clinical trial that observed 18 201 patients (3417 US patients) for a median of 1.8 years between 2006 and 2011.

Interventions

Apixaban therapy vs warfarin therapy.

Main Outcomes and Measures

Within-trial resource use and cost were compared between treatments, using externally derived US cost weights. Life expectancies for US patients were estimated according to their baseline risk and treatment using time-based and age-based survival models developed using the overall ARISTOTLE population. Quality-of-life adjustment factors were obtained from external sources. Cost-effectiveness (incremental cost per quality-adjusted life-year gained) was evaluated from a US perspective, and extensive sensitivity analyses were performed.

Results

Of the 3417 US patients enrolled in ARISTOTLE, the mean (SD) age was 71 (10) years; 2329 (68.2%) were male and 3264 (95.5%) were white. After 2 years of anticoagulation therapy, health care costs (excluding the study drug) of patients treated with apixaban therapy and warfarin therapy were not statistically different (difference, -$60; 95% CI, -$2728 to $2608). Life expectancy, modeled from ARISTOTLE outcomes, was significantly longer with apixaban therapy vs warfarin therapy (7.94 vs 7.54 quality-adjusted life years). The incremental cost, including cost of anticoagulant and monitoring, of achieving these benefits was within accepted US norms ($53 925 per quality-adjusted life year, with 98% likelihood of meeting a $100 000 willingness-to-pay threshold). Results were generally consistent when model assumptions were varied, with lifetime cost-effectiveness most affected by the price of apixaban and the time horizon.

Conclusions and Relevance

Apixaban therapy for ARISTOTLE-eligible patients with atrial fibrillation provides clinical benefits at an incremental cost that represents reasonable value for money judged using US benchmarks for cost-effectiveness.

Trial Registration

clinicaltrials.gov Identifier: NCT00412984.

Idarucizumab, but not procoagulant concentrates, fully restores dabigatran-altered platelet and fibrin components of hemostasis

BACKGROUND

Comparative studies on the restoration of hemostasis with different reversal agents after dabigatran therapy have not been performed. We compared the efficacy and prothrombotic potential of the specific antidote idarucizumab with that of previously recommended non-specific procoagulant concentrates.

STUDY DESIGN AND METHODS

We explored the in vitro effects of dabigatran (184 ng/mL) on fibrin and platelet-aggregate formation onto a damaged vessel under flow conditions (600 s^-1 ). The reversal mechanisms and efficacy of idarucizumab (0.3-3 mg/mL) were compared with that of the non-specific procoagulant concentrates aPCC (25-75 U/Kg), PCC (70 U/Kg), or rFVIIa (120 μg/Kg). Generation of thrombin and prothrombin fragment (F1 + 2), and thromboelastometry parameters of clot formation were measured.

RESULTS

Dabigatran caused pronounced reductions in fibrin (87%) and platelet interactions (36%) with damaged vessels (p < 0.01) and significantly impaired thrombin generation and thromboelastometric parameters (delayed dynamics and reduced firmness). Idarucizumab completely normalized rates of fibrin and platelet coverage to baseline values in flow studies; and reversed the alterations in thrombin generation, F1 + 2 and thromboelastometry parameters produced by dabigatran. In comparison, aPCC and PCC only partially compensated for the dabigatran-induced alterations in fibrin deposition, but were unable to fully restore them to baseline values. Reversal with aPCC or PCC improved the majority of alterations in coagulation-related tests, but tended to overcompensate thrombin generation kinetics and significantly increased F1 + 2 levels.

CONCLUSION

Idarucizumab antagonizes alterations of direct and indirect biomarkers of hemostasis caused by dabigatran. In our studies, idarucizumab was clearly more efficacious than strategies with non-specific procoagulant concentrates and devoid of the excessive procoagulant tendency observed with the latter.

Anti-Xa Oral Anticoagulant Plasma Concentration Assay in Real Life: Rivaroxaban and Apixaban Quantification in Emergency With LMWH Calibrator

BACKGROUND

Oral anti-Xa inhibitors have demonstrated noninferiority to vitamin K antagonists (VKAs) for the prevention of stroke in patients with atrial fibrillation and recurrent venous thromboembolism. They are associated with a decrease in major bleeding. In contrast with VKA, no coagulation monitoring is required. However, in clinical practice, determination of drug concentration is sometimes necessary.

OBJECTIVE

The objective of this study was to evaluate a low-molecular-weight heparin (LMWH) calibrated anti-Xa assay for the quantification of rivaroxaban and apixaban plasma concentration in emergency.

METHODS

The anti-Xa plasma concentration of rivaroxaban and apixaban were measured in emergency in 210 patients using STA anti-Xa liquid assay. For each plasma concentration <150 ng/mL of rivaroxaban or apixaban, an anti-Xa assay calibrated with LMWH was performed.

RESULTS

We demonstrated a significant correlation between LMWH anti-Xa activity and rivaroxaban ( R² = 0.947) or apixaban ( R² = 0.959) concentration and a significant correlation between rivaroxaban and apixaban plasma concentration ( R² = 0.972). A LMWH anti-Xa activity <0.50 IU/mL could exclude a plasma concentration of rivaroxaban and apixaban >30 ng/mL and indicate the feasibility of invasive procedure. Conclusion and Relevance: In the absence of a specific test, LMWH-calibrated anti-Xa assay could be used to determine the presence and evaluate the plasma concentration of oral anti-Xa inhibitors. However, these initial findings require confirmation using other chromogenic calibrated oral anti-Xa assays.

Implementation of a Direct Oral Anticoagulation Screening Service at a Large Academic Medical Center Provided by a Pharmacist-managed Antithrombosis Clinic as a Method to Expand Antithrombotic Stewardship Efforts

Background:

How and when to monitor direct oral anticoagulants (DOACs) for safety and efficacy is a question many anticoagulation clinics are trying to answer. A pharmacist-led antithrombosis clinic (ATC) initiated a clinical service to provide oversight for all prescribed DOACs.

Objective:

Describe the implementation and outcomes of a DOAC screening service.

Methods:

The service was initiated utilizing a daily electronic prescribing report of DOAC prescriptions. Prescriptions were reviewed by clinical pharmacists to assess patient insurance, eligibility, and accuracy of prescribed doses.

Results:

In the first year since service implementation in April 2016, 317 new prescriptions and 595 refill prescriptions were reviewed. A DOAC service pharmacist was able to reach 125 (39.4%) of 317 patients about their new prescription and 59 (9.9%) of 595 refill patients to provide education and follow-up on management as needed. Interventions were performed for 79 (28%) of 317 new prescriptions and 86 (14.5%) of 595 refill prescriptions. Common interventions with new prescriptions include contacting the prescriber for a medication or dose change (25.4%), assistance with medication access (21.5%), and coordinating appropriate lab and provider follow up (21.5%). Common interventions with refill prescriptions include recommending appropriate follow-up (50%) and contacting the prescriber for medication or dosage change (24.4%).

Conclusion:

Implementation of a DOAC screening service identified and resolved dosing errors, improved medication access, provided patient education, and improved follow-up.

Impact and treatment success of new-onset atrial fibrillation with rapid ventricular rate development in the surgical intensive care unit

BACKGROUND

Atrial fibrillation (AF) with rapid ventricular rate (RVR; heart rate >100) in noncardiac postoperative surgical patients is associated with poor outcomes. The objective of this study was to evaluate the practice patterns of AF management in a surgical intensive care unit to determine practices associated with rate and rhythm control and additional outcomes.

MATERIALS AND METHODS

Adult patients (≥18 y) admitted to the surgical intensive care unit (SICU) from June 2014 to June 2015 were retrospectively screened for the development of new-onset AF with RVR. Demographics, hospital course, evaluation and treatment of AF with RVR, and outcome were evaluated and analyzed.

RESULTS

Thousand seventy patients were admitted to the SICU during the study period; 33 met inclusion criteria (3.1%). Twenty-six patients (79%) had rate and rhythm control within 48 h of AF with RVR onset. β-Blockers were the most commonly used initial medication (67%) but were successful at rate and rhythm control in only 27% of patients (6/22). Amiodarone had the highest rate of success if used initially (5/6, 83%) and secondarily (11/13, 85%). Failure to control rate and rhythm was associated with a greater likelihood of comorbidities (100% versus 57%; P = 0.06).

CONCLUSIONS

New-onset AF with RVR in the noncardiac postoperative patient is associated with a high mortality (21%). Amiodarone is the most effective treatment for rate and rhythm control. Failure to establish rate and rhythm control was associated with cardiac comorbidities. These results will help to form future algorithms for the treatment of AF with RVR in the SICU.

Direct Oral Anticoagulants in Emergency Trauma Admissions

BACKGROUND

Direct (non-vitamin-K-dependent) oral anticoagulants (DOAC) are given as an alternative to vitamin K antagonists (VKA) to prevent stroke and embolic disease in patients with atrial fibrillation that is not due to pathology of the heart valves. Fatal hemorrhage is rarer when DOACs are given (nonvalvular atrial fibrillation: odds ratio [OR] 0.68; 95% confidence interval [95% CI: 0.48; 0.96], and venous thromboembolism: OR 0.54; [0.22; 1.32]). 48% of emergency trauma patients need an emergency operation or early surgery. Clotting disturbances elevate the mortality of such patients to 43%, compared to 17% in patients without a clotting disturbance. This underscores the impor tance of the proper, targeted treatment of trauma patients who are aking DOAC.

METHODS

This review is based on articles retrieved by a selective search in PubMed and on a summary of expert opinion and the recommendations of the relevant medical specialty societies.

RESULTS

Peak DOAC levels are reached 2-4 hours after the drug is taken. In patients with normal renal and hepatic function, no drug accumulation, and no drug interactions, the plasma level of DOAC 24 hours after administration is generally too low to cause any clinically relevant risk of bleeding. The risk of drug accumulation is higher in patients with renal dysfunction (creatinine clearance [CrCl] of 30 mL/min or less). Dabigatran levels can be estimated from the thrombin time, ecarin clotting time, and diluted thrombin time, while levels of factor Xa inhibitors can be estimated by means of calibrated chromogenic anti-factor Xa activity tests. Routine clotting studies do not reliably reflect the anticoagulant activity of DOAC. Surgery should be postponed, if possible, until at least 24-48 hours after the last dose of DOAC. For patients with mild, non-life threatening hemorrhage, it suffices to discontinue DOAC; for patients with severe hemorrhage, there are special treatment algorithms that should be followed.

CONCLUSION

DOACs in the setting of hemorrhage are a clinical challenge in the traumatological emergency room because of the inadequate validity of the relevant laboratory tests. An emergency antidote is now available only for dabigatran.

Management of Complications in Anticoagulated Patients with Atrial Fibrillation

Oral anticoagulation is mandatory for patients at high risk of thromboembolism, but the risk of bleeding should also be taken into account. Direct oral anticoagulants are now recommended for non-valvular AF as a potential alternative to warfarin. In this article we discuss methods to assess the anticoagulant effect of these agents, specific and general antidotes, and management of complications such as embolic and haemorrhagic stroke, and significant bleeding.

Patient values and preferences for antithrombotic therapy in atrial fibrillation

Guidelines recommend that patients’ values and preferences should be considered when selecting stroke prevention therapy for atrial fibrillation (SPAF). However, doing so is difficult, and tools to assist clinicians are sparse. We performed a narrative systematic review to provide clinicians with insights into the values and preferences of AF patients for SPAF antithrombotic therapy. Narrative systematic review of published literature from database inception. Research questions: 1) What are patients’ AF and SPAF therapy values and preferences? 2) How are SPAF therapy values and preferences affected by patient factors? 3) How does conveying risk information affect SPAF therapy preferences? and 4) What is known about patient values and preferences regarding novel oral anticoagulants (NOACs) for SPAF? Twenty-five studies were included. Overall study quality was moderate. Severe stroke was associated with the greatest disutility among AF outcomes and most patients value the stroke prevention efficacy of therapy more than other attributes. Utilities, values, and preferences about other outcomes and attributes of therapy are heterogeneous and unpredictable. Patients’ therapy preferences usually align with their values when individualised risk information is presented, although divergence from this is common. Patients value the attributes of NOACs but frequently do not prefer NOACs over warfarin when all therapy-related attributes are considered. In conclusion, patients’ values and preferences for SPAF antithrombotic therapy are heterogeneous and there is no substitute for directly clarifying patients’ individual values and preferences. Research using choice modelling and tools to help clinicians and patients clarify their SPAF therapy values and preferences are needed.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Management of Elective Surgery and Emergent Bleeding with Direct Oral Anticoagulants

PURPOSE OF REVIEW

The purpose of this review was to offer practical management strategies for when patients receiving direct oral anticoagulants require elective surgery or present with bleeding complications.

RECENT FINDINGS

Clinical practice guidelines are now available on the timing of periprocedural interruption of treatment with the newer direct oral anticoagulants based on their pharmacodynamics and pharmacokinetics and based on findings from cohort studies and clinical trials. An antibody that reverses the effects of dabigatran is now available, and a factor Xa decoy is being developed as an antidote to apixaban, betrixaban, edoxaban, and rivaroxaban. The timing of interruption of direct oral anticoagulants for elective surgery is based on multiple factors, including pharmacologic properties and interactions, the patient's renal function, and the type of planned surgery. There is little role for low-molecular-weight heparin bridging. Idarucizumab is the treatment of choice for dabigatran-related life-threatening bleeding, while andexanet alfa is being developed to reverse factor Xa inhibitors.

Systemic Octreotide Therapy in Prevention of Gastrointestinal Bleeds Related to Arteriovenous Malformations and Obscure Etiology in Atrial Fibrillation

OBJECTIVES

The present study describes the use of octreotide (OCT) in patients with atrial fibrillation (AF) receiving oral anticoagulation (OAC) who have gastrointestinal (GI) bleeding related to arteriovenous malformations (AVMs), as well as its effect on OAC tolerance and subsequent rebleeding.

BACKGROUND

AVMs cause significant GI bleeding, especially in patients with AF who are receiving OAC for stroke prevention. OCT has been shown to minimize recurrent GI bleeds related to AVMs.

METHODS

In a multicenter, observational study, 38 AF patients with contraindications to OAC because of AVM-related GI bleeding were started on 100 μg of subcutaneous OCT twice daily. OAC was resumed in all patients within 48 h. Incidence of recurrent GI bleeds was calculated, and hemoglobin levels were recorded at enrollment and at 3 and 6 months' follow-up.

RESULTS

After a median follow-up of 8 months, 36 patients (mean age 69 ± 8.0 years; mean CHA₂DS₂-VASc score 3 ± 1 and mean HAS-BLED score 3 ± 1) were available for analysis. All were able to successfully resume OAC, and 28 of 36 (78%) remained on OAC at the conclusion of the study, whereas 8 underwent left atrial appendage closure with subsequent OAC discontinuation. No systemic thromboembolic events occurred in follow-up. Of the 28 patients who continued receiving OAC, 19 (68%) were free of recurrent GI bleed, 4 had minor GI bleeds, 4 required transfusion, and 1 required colectomy for GI bleeding. Mean hemoglobin levels in all patients receiving OAC were significantly higher at 3- and 6-month follow-up than at baseline (p < 0.001).

CONCLUSIONS

Subcutaneous OCT therapy is an attractive option in AF patients receiving OAC who have AVM-related GI bleeds. It allows successful reinitiation of OAC as a bridge to left atrial appendage exclusion or short-term relief from bleeding.

Anticoagulation in Pulmonary Embolism: Update in the Age of Direct Oral Anticoagulants

The emergence of direct oral anticoagulants (DOACs) represents a major advancement and paradigm shift in the treatment of venous thromboembolism. Currently, dabigatran, rivaroxaban, apixiban, and edoxoban are approved and used routinely for the prevention and treatment of patients with venous thromboembolism. Because each of the DOACs has different doses and dosing regimens, clinicians need to become familiar with their use. This article focuses on the practical considerations of how and when to use the DOACs. It also aims to explore follow-up monitoring, use in special populations, reversal agents, periprocedural management, and how to handle bleeding complications with the DOACs.

Emerging therapeutic uses of direct-acting oral anticoagulants: An evidence-based perspective

Direct-acting oral anticoagulants (DOACs) were claimed to cause a potential paradigm shift in the therapeutic scenario of patients requiring short- and long-term anticoagulation, by virtue of their pharmacological properties, perceived as innovative. The evidence gathered so far (from pre-approval pivotal trials to real-world post-marketing observational data) consistently confirmed that DOACs are overall comparable to vitamin-K antagonists (VKAs) in terms of safety, efficacy and effectiveness and unequivocally documented a consistent and clinically relevant reduced risk of intracranial bleeding in the settings of non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE). Interestingly, two parallel paths can be identified in the current research scenario: A) in the aforementioned consolidated therapeutic indications, an innovative approach is directed towards tailored treatment strategies, to identify patients most likely to benefit from one of the different anticoagulant drugs, in particular subpopulations at increased risk of adverse events (e.g., bleeding); B) in unconventional settings, DOACs are gaining interest for potential use in emerging diseases characterized by arterial and venous thromboembolic risk. In these scenarios, the risk-benefit profile of DOACs, as compared to VKAs or heparins, is less defined. The aim of this review is to critically assess the body of evidence underlying emerging therapeutic uses of DOACs (e.g., heparin-induced thrombocytopenia, anti-phospholipid antibody syndrome), including evolving issues in special populations (e.g., patients with VTE and cancer or cirrhosis). This will be achieved by analyzing the strength (i.e., systematic reviews, randomized clinical trials, observational studies, case report/series) and consistency (i.e., concordance) of both published and unpublished evidence registered in major public repositories.