A China-Based Cost-Effectiveness Analysis of Novel Oral Anticoagulants versus Warfarin in Patients with Left Ventricular Thrombosis

Purpose

This study aims to conduct a comprehensive cost-effectiveness comparison between novel oral anticoagulants (NOACs) and warfarin in Chinese patients with left ventricular thrombosis (LVT). By incorporating the impact of volume-based procurement (VBP) policy for pharmaceuticals in China, this analysis intends to provide crucial insights for informed healthcare decision-making.

Patients and Methods

A Markov model was employed to simulate the disease progression of LVT over a 54-week time horizon, using weekly cycles and six mutually exclusive health states. The model incorporated transition probabilities between health states calculated based on clinical trial data and literature sources. Various cost and utility parameters were also included. Additionally, a series of sensitivity analyses were conducted to address parameter variations and associated uncertainties.

Results

The study finding suggest that from the perspective of Chinese healthcare, the majority of brand-name drug (BND) NOACs generally lack cost-effectiveness when compared to warfarin. However, when considered the VBP policy, NOACs, particularly rivaroxaban, prove to be more cost-effective than warfarin. Rivaroxaban provided an additional 0.0304 quality-adjusted life years (QALYs) per patient and reduced overall medical costs by 9095.73 CNY, resulting in an incremental cost-effectiveness ratio (ICER) of -298,786.20 CNY/QALY. Sensitivity analysis indicated a 78.4% probability of any NOACs being more cost-effective compared to warfarin. However, specifically considering NOACs under the VBP policy, the likelihood of them being more cost-effective approached 90%.

Conclusion

Taking into account Chinese pharmaceutical procurement policies, the findings highlight the superior efficacy of NOACs, especially rivaroxaban, in enhancing both the quality of life and economic benefits for Chinese LVT patients. NOACs present a more cost-effective treatment option, improving patient quality of life and healthcare cost efficiency compared to warfarin.

The Prescription trends and dosing appropriateness analysis of novel oral anticoagulants in ischemic stroke patients: a retrospective study of 9 cities in China

Background: Novel oral anticoagulants (NOACs) have been recommended by guidelines as the first-line drugs for preventing cardiogenic stroke. We aimed to provide an overview of the prescription trends and dosing appropriateness of NOACs in China. Methods: We conducted a retrospective analysis of NOAC prescriptions using the Hospital Prescription Analysis Cooperation Project data from 2016 to 2022. Various patient features, such as gender, age, city, year, source, department visited, original diagnosis, dosing, cost, and insurance type, were collected and analyzed to examine the trends and dosing appropriateness of NOAC usage in ischemic stroke patients. Results: 62,014 NOAC prescriptions were analyzed, including 16,602 for dabigatran, 45,253 for rivaroxaban, and 159 for apixaban. 85.14% of the patients were aged 65 or above, and tertiary hospitals accounted for 95.97% of NOAC prescriptions. NOAC prescriptions rose from 1828 in 2016 to 13,998 in 2021 but dropped to 13,166 in 2022. The percentage of annual prescriptions for NOACs among stroke patients has increased from 0.05% in 2016 to 0.37% in 2022. Total drug cost increased from ¥704541.18 in 2016 to ¥4128648.44 in 2021, then decreased to ¥1680109.14 in 2022. Prescriptions were divided into 48,321 appropriate and 11,262 inappropriate dosing groups, showing significant differences in medications, age, year, city type, hospital level, source, insurance type, and department visited (all p < 0.001). The median drug cost for inappropriate dosing was higher than for appropriate dosing (¥55.20 VS ¥83.80). The top comorbidities in ischemic stroke patients were atrial fibrillation (35.30%), hypertension (32.75%), and coronary heart disease (16.48%). Conclusion: The application of NOACs in the Chinese population is increasing. Our findings highlight the frequent deviation from labeled dosing of NOACs in clinical practice. Continued efforts are necessary to promote the appropriate use of NOACs according to the standard dosage in the drug insert.

Optimizing Atrial Fibrillation Care: Comparative Assessment of Anticoagulant Therapies and Risk Factors

BACKGROUND AND OBJECTIVES

Atrial fibrillation (AF) is a common arrhythmia associated with various risk factors and significant morbidity and mortality.

MATERIALS AND METHODS

This article presents findings from a study involving 345 patients with permanent AF. This study examined demographics, risk factors, associated pathologies, complications, and anticoagulant therapy over the course of a year.

RESULTS

The results showed a slight predominance of AF in males (55%), with the highest incidence in individuals aged 75 and older (49%). Common risk factors included arterial hypertension (54%), dyslipidemia, diabetes mellitus type 2 (19.13%), and obesity (15.65%). Comorbidities such as congestive heart failure (35.6%), mitral valve regurgitation (60%), and dilated cardiomyopathy (32%) were prevalent among the patients. Major complications included congestive heart failure (32%), stroke (17%), and myocardial infarction (5%). Thromboembolic and bleeding risk assessment using CHA2DS2-VASc and HAS-BLED scores demonstrated a high thromboembolic risk in all patients. The majority of patients were receiving novel oral anticoagulants (NOACs) before admission (73%), while NOACs were also the most prescribed antithrombotic therapy at discharge (61%).

CONCLUSIONS

This study highlights the importance of risk factor management and appropriate anticoagulant therapy in patients with AF, to reduce complications and improve outcomes. The results support the importance of tailored therapeutic schemes, for optimal care of patients with AF.

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.

Treatment of Persistent Left Atrial Appendage Thrombus in Patients with Atrial Fibrillation on Adequate Oral Anticoagulation: Pathways of Care for All-comers and Heart Failure Patients

In patients with AF, the presence of left atrial/left atrial appendage (LA/LAA) thrombus is related to an increased risk of thromboembolic events. Anticoagulation therapy, either with vitamin K antagonists or novel oral anticoagulants (NOACs) is therefore mandatory in AF with LA/LAA thrombus in order to lower the risk of stroke or other systemic embolic events. Despite the efficacy of these treatments, some patients will have persistent LAA thrombus remaining or may have contraindications to oral anticoagulation. Currently, little is known about the occurrence, risk factors and resolution rate of LA/LAA thrombus in patients who are already under optimal chronic oral anticoagulation, including vitamin K antagonists or NOACs. The common action in clinical practice in this scenario is switching from one to another anticoagulant drug exhibiting a different mechanism of action. Repeated cardiac imaging is then advised within several weeks to visually verify thrombus dissolution. Finally, there is a substantial scarcity of data on the role and optimal use of NOACs after LAA occlusion. The aim of this review is to critically evaluate data and provide up-to-date information on the best antithrombotic strategies in this challenging clinical scenario.

Comparative differences in the risk of major gastrointestinal bleeding among different direct oral anticoagulants: An updated traditional and Bayesian network meta-analysis

Background: The most favorable gastrointestinal (GI) bleeding safety profile among different types of direct oral anticoagulants (DOACs) remains controversial. This meta-analysis includes the latest studies and aims to compare GI bleeding risk associated with the use of various DOACs. Methods: PubMed, Cochrane library, and clinicaltrial.gov were searched. Randomized control trials (RCTs) evaluating the safety of DOACs were identified. The primary endpoint assessed was major GI bleeding. Results: A total of 37 RCTs were included in the analyses. Based on the traditional meta-analysis, the major GI bleeding risk was different among various DOACs (interactive p-value <.10). Network meta-analysis findings showed that no DOACs increased the risk of major GI bleeding compared with conventional therapy. Furthermore, a 10 mg daily administration of apixaban reduced the major GI bleeding risk more than daily doses of 60 mg edoxaban, ≥15 mg rivaroxaban, and 300 mg dabigatran etexilate. No difference was observed between daily doses of 300 mg dabigatran etexilate, 60 mg edoxaban, and ≥15 mg rivaroxaban. The major GI bleeding risk associated with 30 mg daily dose of edoxaban was lower than with 10 mg daily rivaroxaban, and no differences between daily 5 mg apixaban, 30 mg edoxaban, and 220 mg dabigatran etexilate were observed. Conclusion: Differences in the major GI bleeding risk were observed when various DOACs were compared. Among standard-dose DOACs, apixaban was associated with the lowest degree of major GI risk. Among low-dose DOACs, edoxaban was associated with a lower major GI bleeding risk than rivaroxaban.

Clinical and Safety Outcomes Associated with Extended Treatment of Venous Thromboembolism: A Network Meta-Analysis

BACKGROUND

Many anticoagulant strategies are available for the extended treatment of venous thromboembolism, yet little guidance exists regarding which drug is most effective and safe.

AIM

A network meta-analysis was performed to resolve this uncertainty.

METHODS

We searched the medical literature through June 2022 for randomized controlled trials (RCTs) evaluating the efficacy and safety of anticoagulants for adults with VTE compared with other anticoagulants or a placebo.

RESULTS

We identified 13 eligible RCTs in 12 articles. All pooled hazard ratios (HR) and 95% credible intervals (CrI) mentioned below, except that for aspirin, were calculated by comparison with standard-intensity warfarin. Novel oral anticoagulants (NOACs) were not inferior to standard-intensity warfarin in preventing recurrence, and edoxaban was ranked first among the NOACs (HR, 0.99; 95% CrI, 0.70-1.39). All the NOACs, except rivaroxaban, were superior to standard-intensity warfarin in preventing bleeding events. Apixaban was ranked first and was considered to be safer than other NOACs for control of both major bleeding (HR = 0.07, 95% CrI: 0.01-0.37) and clinically relevant non-major bleeding (CRNMB, HR = 0.30, 95% CrI: 0.13-0.67). Edoxaban was ranked second among the NOACs for control of major bleeding (HR = 0.44, 95% CI: 0.21-0.88), and dabigatran was ranked second among the NOACs for control of CRNMB (HR = 0.54, 95% CrI: 0.4-0.73).

CONCLUSIONS

There existed no statistically significant differences in recurrence between NOACs and standard-intensity warfarin, and NOACs were associated with a lower risk of bleeding events. Edoxaban effectively prevented VTE recurrence and major bleeding, and apixaban was the best anticoagulant for controlling bleeding events.

Proportion of Patients on Warfarin Therapy Who Are Eligible for Conversion to a Direct Oral Anticoagulant in the Setting of COVID-19

Background:

Warfarin, a commonly prescribed anticoagulant, requires frequent lab monitoring. Lab monitoring puts patients at risk of COVID-19 exposure and diverts medical resources away from health care systems. Direct oral anticoagulants (DOACs) do not require routine therapeutic monitoring and are indicated first line for nonvalvular atrial fibrillation (NVAF) stroke prevention and venous thromboembolism (VTE) prevention/treatment.

Objective:

The purpose of the study was to determine the proportion of patients who qualify for DOACs and assess for predictors of qualification.

Methods:

This cross-sectional study investigated patients on warfarin managed by Michigan Medicine Anticoagulation Service. Direct oral anticoagulant eligibility criteria were established using apixaban, dabigatran, and rivaroxaban package inserts. Patient eligibility was determined through chart review. The primary outcome was the proportion of patients who qualify for DOACs based on clinical factors. Predictors of DOAC qualification were assessed.

Results:

This study included 3205 patients and found 51.8% (n = 1661) of patients qualified for DOACs. Qualifying patients were older (71.9 vs 59.4 years, P < 0.0001) with a higher CHA₂DS₂ VASc (3.7 vs 3.4, P < 0.0007). The primary disqualifying factor was extreme weight, high and low. Accounting for a patient’s sex and referral source, age > 65 (odds ratio [OR] = 1.9, P < 0.0001) and NVAF indication (OR = 5.6, P < 0.0001) were significant predictors for DOAC qualification.

Conclusion and Relevance:

Approximately 52% of patients on warfarin were eligible for DOACs. This presents an opportunity to reduce patient exposure to health care settings and health care utilization in the setting of COVID-19. Increased costs of DOACs need to be assessed.

Gastrointestinal Bleeding Due to NOACs Use: Exploring the Molecular Mechanisms

Novel oral anticoagulants (NOACs) are drugs approved for the prevention and treatment of many thromboembolic cardiovascular conditions as a safer alternative to warfarin. We reviewed studies published in PubMed^®, UpToDate^®, Web of Science^®, and Cochrane^® about NOACs' risks and benefits in patients requiring anticoagulation, with a focus on gastrointestinal bleeding and on molecular and pathophysiological mechanisms underlying the risk of bleeding in patients treated with them. Apixaban resulted in a lower rate of gastrointestinal bleeding compared to dabigatran and rivaroxaban. However, data reported that gastrointestinal bleeding in patients treated with NOACs was less severe compared to warfarin. Studies show promising results on the increased and widespread use of NOACs in patients who require anticoagulation (for example-in case of atrial fibrillation or high risk of venous thromboembolism), reporting an overall lower risk of major bleeding events. The profile of NOACs was more effective and secure compared to warfarin, but a more careful medical prescription is required in patients who are at high risk of gastrointestinal bleeding.

In Vitro Apixaban Removal By CytoSorb Whole Blood Adsorber: An Experimental Study

OBJECTIVES

The use of unopposed oral anticoagulants while undergoing cardiothoracic surgery is associated with severe bleeding and increased morbidity. The aim of this experimental study was to examine if the apixaban concentration in reconstituted blood could be reduced in an in vitro setup by the use of CytoSorb whole blood adsorber, and to study how this affected global coagulation assays.

DESIGN AND SETTING

An experimental study performed in a laboratory.

PARTICIPANTS

An in vitro setup with reconstituted whole blood.

INTERVENTIONS

Reconstituted whole blood spiked with apixaban circulated in an in vitro circuit with the CytoSorb 300 mL device connected.

MEASUREMENTS AND MAIN RESULTS

Blood samples were drawn at 0, 5, 15, 30, 60, and 120 minutes of adsorption. The apixaban concentration was measured at each time point. In addition, the global coagulation assays, thromboelastometry clotting time and thrombin generation, were performed, and the results were compared with baseline values obtained before spiking blood with apixaban. After 30 minutes of adsorption, the mean apixaban concentration was reduced from 414.3 (±69.1) ng/mL to 33 (±11.4) ng/mL. Thrombin generation showed maximum effect after 60 minutes, and the thromboelastometry clotting time was close to baseline values after 120 minutes.

CONCLUSIONS

In this in vitro study, apixaban concentrations were effectively reduced, and the clotting time and thrombin generation assays were normalized by the use of CytoSorb whole blood adsorber.

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.

Novel oral anticoagulants versus vitamin K antagonists in patients with atrial fibrillation after transcatheter aortic valve replacement: A systematic review and meta-analysis

BACKGROUND

The efficacy and safety of novel oral anticoagulants (NOACs) compared to the current guideline-recommended vitamin K antagonists (VKAs) in atrial fibrillation (AF) patients undergoing transcatheter aortic valve replacement (TAVR) has not been well established. We pooled evidence from all available studies to assess the risks and benefits of this drug class.

METHODS

We queried electronic databases (MEDLINE, Scopus, and Cochrane central) up until January 28th, 2022 for studies comparing NOACs to VKAs in AF patients undergoing TAVR. Results from studies were presented as risk ratios (RR) and pooled using a random-effects model. Subgroup analysis by study design and meta-regression analysis were performed to explore heterogeneity.

RESULTS

A total of 12 studies (3 RCTs and 9 observational) containing 12,203 patients (mean age 81.2 years; 50.5% men) were identified and included in the analysis. Pooled analysis revealed no significant difference between NOACs and VKAs in terms of stroke or systemic embolism (RR: 0.78; p = 0.18), major bleeding (RR: 0.84; p = 0.32), intracranial hemorrhage (RR 0.61; p = 0.06), all-cause mortality (RR: 0.69; p = 0.07), and myocardial infarction (RR: 1.60; p = 0.24) at a mean length of follow-up of 15.1 months. RCTs and observational studies did not significantly differ across outcomes on subgroup analysis. Meta-regression analysis found heterogeneity in all-cause mortality to be significantly explained by percentage of males (coefficient: 0.049, p = 0.007), mean age (coefficient: 0.221, p < 0.001), and CHA2DS2-VASc score (coefficient: -1.657, p < 0.001).

CONCLUSIONS

This meta-analysis suggests that outcomes with NOACs do not significantly differ compared to VKAs following TAVR in patients with AF.

Bleeding Outcomes After Dental Extraction in Patients Under Direct-Acting Oral Anticoagulants vs. Vitamin K Antagonists: A Systematic Review and Meta-Analysis

Background: The current systematic review aimed to compare bleeding outcomes in dental extraction patients receiving uninterrupted Direct-acting oral anticoagulant (DOAC) or Vitamin K antagonists (VKAs) for various systemic diseases.

Methods: PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar databases were searched for randomized controlled trials, controlled clinical trials, prospective and retrospective cohort studies, and case control studies, conducted on adult patients undergoing dental extraction under uninterrupted DOAC or VKAs therapy and reporting bleeding outcomes. The search was conducted up to March 31, 2021. We pooled data to calculate risk ratios (RR) with 95% confidence intervals (CI) in a random-effects model.

Results: Eight studies comparing 539 patients on DOAC therapy and 574 patients on VKAs were included. Meta-analysis indicated a statistically significant lower bleeding risk in patients under DOAC therapy (RR 0.68 95% CI 0.49, 0.95 I² = 0%). However, on sensitivity analysis, the results were statistically non-significant after exclusion of any of the included studies. On pooled analysis of limited number of studies, we found no statistically significant difference in the risk of bleeding between apixaban (RR 0.85 95% CI 0.45, 1.60 I² = 0%), rivaroxaban (RR 0.95 95% CI 0.36, 2.48 I² = 45%), dabigatran (RR 0.49 95% CI 0.19, 1.28 I² = 5%), edoxaban (RR 0.41 95% CI 0.13, 1.27 I² = 0%) and VKAs.

Conclusion: The results of the first review comparing bleeding outcomes after dental extraction in patients on uninterrupted DOAC or VKA therapy indicates that patients on DOAC may have a reduced risk of hemorrhage. Current evidence is of very low-quality and should be interpreted with caution. Data on individual DOAC is scarce and at this point, the difference in the risk of bleeding between these drugs cannot be elucidated. Further studies with a large sample size shall supplement our conclusion.

Novel Drug Interaction index and Risk of Mortality in Older Patients With Atrial Fibrillation Receiving Non Vitamin K Oral Anticoagulants (NOEL Drug)

Drug interactions with novel oral anticoagulants (NOACs) may decrease their advantages. We aimed to explore the drug interaction rates with NOACs and impacts of drug interaction index (DII) on mortality among older patients with atrial fibrillation (AF). In this retrospective cohort study, we enrolled 704 eligible patients aged 65≤ with AF between January 1, 2018 and December 30, 2019 in a tertiary outpatient cardiology clinic. We recorded demographic, clinical characteristics, and medications for the last 3 months. At the end of the evaluation visit (March 1, 2020), death events and dates were recorded. All medications were checked for drug interactions using Lexicomp® software. Each drug interaction was annotated according to risk grade. Moreover, we determined a new index ratio of C/D/X classes to total interactions called DII. The mean age was 75.19  ±  7.13 and 398 (56%) were male. Death events were observed in 106 (15%) patients. A total of 9883 drugs were analyzed for drug interactions. The majority of drug interactions were in class A (80.7%). Clinically relevant interactions were 14.6% (Class C/D/X). The area under receiver operating characteristic curve was 0.704 (95% confidence interval: 0.653-0.754) and 0.167 cutoff value (68.9% sensitivity and 80.2% specificity [3.11 positive likelihood ratio]) for DII to predict mortality. This study showed an overview of the NOACs interactions in older patients with AF. Additionally, the inappropriate NOAC dose and DII showed an association with mortality. NOAC treatment should be guided by drug interaction applications to reduce mortality.

The risk of gastrointestinal hemorrhage with non-vitamin K antagonist oral anticoagulants: A network meta-analysis

BACKGROUND

Non-vitamin K antagonist oral anticoagulants (NOACs) have been widely used for stroke prevention in atrial fibrillation (AF) and the treatment and prevention of venous thromboembolism. There is an issue with safety, especially in clinically relevant bleeding. We performed a network meta-analysis to evaluate the risk of major gastrointestinal (GI) bleeding associated with NOACs.

METHODS

Interventions were warfarin, enoxaparin, apixaban, dabigatran, edoxaban, and rivaroxaban. The primary outcome was the incidence of major GI bleeding. A subgroup analysis was performed according to the following indications: AF, deep venous thrombosis/pulmonary embolism, and postsurgical prophylaxis.

RESULTS

A total of 29 randomized controlled trials (RCTs) and 4 large observation population studies were included. Compared with warfarin, apixaban showed a decreased the risk of major GI bleeding (relative risk [RR] 0.54, 95% confidence interval [CI] 0.25-0.76), and rivaroxaban tended to increase this risk (RR 1.40, 95% CI 1.06-1.85). Dabigatran (RR 1.25, 95% CI 0.98-1.60), edoxaban (RR 1.07, 95% CI 0.69-1.65), and enoxaparin (RR 1.24, 95% CI 0.63-2.43) did not significantly increase the risk of GI bleeding than did warfarin. In the subgroup analysis, according to indications, apixaban showed a decreased risk of major GI bleeding (RR 0.50, 95% CI 0.34-0.74) than did warfarin in AF studies. Dabigatran (RR 2.36, 95% CI 1.55-3.60, and rivaroxaban (RR 1.75, 95% CI 1.10-6.41) increased the risk of major GI bleeding than did apixaban. An analysis of studies on venous thromboembolism or pulmonary embolism showed that no individual NOAC or enoxaparin was associated with an increased risk of major GI bleeding compared to warfarin.

CONCLUSION

Individual NOACs had varying profiles of GI bleeding risk. Results of analyses including only RCTs and those including both RCTs and population studies showed similar trends, but also showed several differences.

Comparative effectiveness and safety of non-vitamin-K antagonist oral anticoagulants and warfarin in older adults with atrial fibrillation and diabetes

OBJECTIVE

To evaluate comparative effectiveness and safety of non-vitamin-K antagonist oral anticoagulants (NOACs) versus warfarin in Medicare beneficiaries with non-valvular atrial fibrillation (NVAF) and comorbid diabetes mellitus (DM).

METHODS

A retrospective cohort study using 2014-2016 5% national Medicare data was undertaken. NVAF patients with DM aged ≥65 years having at least one prescription for NOACs or warfarin between July 2014 and December 2015 were included in the study. Propensity score matching was used to balance demographic and baseline clinical characteristics of patients in two treatment groups. Cardiovascular outcomes including stroke/systemic embolism (SE) and myocardial infarction (MI) were evaluated to measure effectiveness. Assessment of safety outcomes included intracranial hemorrhage (ICH), major gastrointestinal bleeding (MGB), bleeding from other sites (OB) and all-cause mortality. Stratified Cox proportional hazards models were used to estimate hazard ratios for the outcomes in the matched cohort.

RESULTS

The matched sample consisted of 4582 patients (2291 pairs). Compared to warfarin, NOACs had a significantly lower risk of stroke/SE (hazard ratio (HR): 0.373, 95% confidence interval (CI): 0.247-0.564, p < .001) and all-cause mortality (HR: 0.783, CI: 0.656-0.873, p = .007). NOACs were found to significantly reduce the risk of ICH (HR: 0.500, CI: 0.300-0.834, p = .008) and OB (HR: 0.608, CI: 0.424-0.870, p = .007), but no difference was observed in the risk of MGB (HR: 0.862, CI: 0.640-1.160, p = .326) between NOACs and warfarin. The composite outcome demonstrated superior overall effectiveness and safety of NOAC therapy compared to warfarin therapy (HR: 0.685, CI: 0.587-0.801, p < .001).

CONCLUSION

Oral anticoagulation therapy with NOACs was found to be more effective than warfarin therapy among older adults with NVAF and comorbid DM.

Comparison of Novel Oral Anticoagulants and Vitamin K Antagonists in Patients With Cerebral Venous Sinus Thrombosis on Efficacy and Safety: A Systematic Review

Vitamin K antagonists (VKAs) are guideline-suggested subacute anticoagulants for cerebral venous sinus thrombosis (CVST), although there is potential hemorrhage risk in clinical use. In the last decade, novel oral anticoagulants (NOACs) have been applied as an alternative to VKAs in some kinds of thromboembolic diseases. Whether NOACs could replace VKAs in CVST treatment remains unclear. We conducted a comparison between the two types of medicines on efficacy and safety for the treatment of CVST based on the present clinical evidence from a literature search. Six studies [four retrospective studies, one prospective study, and 1 randomized clinical trial (RCT)] including 398 patients were included. Data suggested no significant difference between NOACs and VKAs in terms of recurrence of venous thrombotic events (VTEs) or death [risk ratio (RR) = 0.34, 95% confidence interval (CI) 0.06-1.98], partial recanalization (RR = 0.97, 95% CI 0.93-1.14), and overall hemorrhage events (RR = 0.86, 95% CI 0.47-1.58). In conclusion, the application of NOACs for CVST is similar to that of VKAs in terms of efficacy and safety.

Mechanical thrombectomy for acute ischaemic stroke during therapeutic anticoagulation: long-term outcomes

AIM OF STUDY

Mechanical thrombectomy (MT) is one of the aetiological treatment options recommended for anticoagulated patients with acute ischaemic stroke (AIS). We analysed its long-term outcomes using the modified Rankin Score (mRS) or mortality on day 90.

CLINICAL RATIONALE FOR THE STUDY

Data describing the anticoagulant efficacy and safety of MT in patients with AIS is limited.

MATERIALS AND METHODS

This study included 291 patients with AIS (49% women, mean [SD] age 66 [15] years) who underwent MT in the Comprehensive Stroke Centre in Krakow, Poland. Data describing demographics, stroke risk factors, NIHSS on admission, postprocedural thrombolysis in cerebral infarction score, 24-hour postprocedural haemorrhagic transformation (ECASS-2) as seen on computed tomography, and time between stroke onset and groin puncture was collected. The outcome measure was the mRS on day 90 after stroke onset (a favourable outcome was defined as an mRS not exceeding 2 points; an unfavourable outcome was death).

RESULTS

Thirty-seven patients (13%) were on therapeutic anticoagulation during MT. Univariate analysis showed that anticoagulated patients were older and more likely to have been diagnosed with hypertension, ischaemic heart disease, or atrial fibrillation. The patient groups did not differ in terms of clot location, postprocedural thrombolysis in cerebral infarction score, haemorrhagic transformation on computed tomography, or mRS on day 90. Multivariate logistic regression analysis showed that younger age, male sex, no history of diabetes mellitus, lower NIHSS score on admission, shorter time between stroke onset and groin puncture, and better recanalisation were associated with favourable outcomes at day 90, and that therapeutic anticoagulation was not (OR, 1.00; 95%CI, 0.46-2.15; p = 0.99). Anticoagulation did not affect mortality at day 90 (OR, 1.28; 95%CI, 0.56-2.92; p = 0.55).

CONCLUSION AND CLINICAL IMPLICATIONS

In anticoagulated patients with AIS, MT does not affect long-term outcomes.

Novel Dual Therapy: A Paradigm Shift in Anticoagulation in Patients of Atrial Fibrillation Undergoing Percutaneous Coronary Intervention

Patients with atrial fibrillation (AF) on long-term oral anticoagulation (OAC) either have underlying coronary artery disease or suffer from acute coronary syndromes necessitating a percutaneous coronary intervention (PCI). In such a scenario, an amalgamation of antiplatelet and antithrombotic therapy (conventionally called as “triple therapy”) is obligatory for preventing coronary ischemia and stroke. But such ischemic benefits are accrued at the cost of increased bleeding. We also now know that bleeding events following PCI are related to increased mortality. Balancing the bleeding and ischemic risks is often a clinical dilemma. With the advent of novel oral anticoagulants (NOAC's) with preserved efficacy and attenuated bleeding rates, anticoagulation in AF is undergoing paradigm shift. The spotlight is now shifting from conventional triple therapy (vitamin-K antagonist + dual antiplatelet therapy [VKA + DAPT]) to novel dual therapy (NOAC + single antiplatelet therapy [SAPT]) in situation of anticoagulated AF patients undergoing PCI. Such a strategy aims to ameliorate the higher bleeding risk with conventional VKA's while retaining the ischemic benefits. In this review, we briefly discuss the need for combination therapy, trials of novel dual therapy, strategies for mitigating bleeding, the current guidelines, and the future perspectives in AF undergoing PCI with stent(s).

Knowledge, attitude, and practice of institutional dental professionals regarding management of patients taking oral antithrombotic medications

OBJECTIVES

Nowadays, there is an increasing number of patients prescribed regular antithrombotics. With these long-term medications, complications like postoperative bleeding are extremely important. Despite available guidelines on this issue, disparities in approach have been noticed. The current study aimed to explore the knowledge, attitude, and practice of dental professionals associated with a dental school in Saudi Arabia regarding the management of patients with oral antithrombotic medications.

METHOD AND MATERIALS

A cross-sectional study was conducted on institutional-based dental professionals in Saudi Arabia. Fifty-six subjects, including 12 interns, 20 demonstrators, and 24 faculty members were included in the study. A modified semistructured questionnaire comprising 20 questions was used to gather respondents' knowledge, attitude, and practice related to oral antithrombotic medications. The chi-square test was applied for computing inferential statistics. Spearman correlation coefficient was performed for significant variables.

RESULTS

The faculty members had comparable knowledge (P = .010) as well as practice (P = .001) levels, and significantly outscored the other two groups. The interns displayed a significantly higher knowledge score over the demonstrators, whereas the reverse scenario was seen for practice scores. Interestingly, participants were frequently found to be significantly overestimating the bleeding risk for procedures falling into the "no risk" category. A significantly positive correlation regarding the professional level could be shown in all domains.

CONCLUSION

Professionals need to regularly update about novel anticoagulants, and should strictly comply with the established practice guidelines, thus improving the quality, safety, and value of dental health care.

Shared decision making for thromboembolic prophylaxis in non-valvular atrial fibrillation: promise and problems with the American College of Cardiology's AnticoagEvaluator (based on SPARCtool)

BACKGROUND AND METHODS

People with atrial fibrillation face an increased risk of thromboembolic events, and deciding on an antithromboembolic strategy in non-valvular atrial fibrillation is a prime opportunity for shared decision making. Therefore, tools facilitating this process are highly desirable. The American College of Cardiology strives for such with its 'AnticoagEvaluator', which is based on Peter Loewen's 'SPARCtool'. However, it appears these tools were released without standard peer review. Therefore, an analysis of these tools was undertaken to evaluate their soundness, namely proper use of baseline risk and effect estimates from the available evidence.

RESULTS

Despite Loewen's laudable idea and the American College of Cardiology developing AnticoagEvaluator based on Loewen's work, both tools have a flaw: they use relative effect estimates based on composite outcomes (thromboembolic and haemorrhagic) that do not match the baseline risk to which they are applied (thromboembolic). This can lead to importantly inaccurate impressions of therapeutic efficacy. This analysis explores this issue and offers potential solutions.

CONCLUSIONS

The American College of Cardiology releasing and promoting a tool that gives misleading impressions of therapeutic efficacy is of considerable importance, though SPARCtool should also be corrected as a matter of importance. Means to correct the tools are identified herein, and if corrected, these tools stand to better fulfil their intended purpose as important and useful additions for clinical and shared decision making. This article's analysis of the tools has a directly practical purpose, but it also serves as an instructive example of key elements of evidence-based medicine and shared decision making.

Real-world adherence to oral anticoagulants in atrial fibrillation

Introduction: In the treatment of non-valvular atrial fibrillation (AF) with oral anticoagulant (OAC), the patients' adherence to therapy is a very important factor in stroke prevention. Aim: To investigate the one-year persistence of different OAC therapies (vitamin K antagonist [VKA] and new oral anticoagulants [NOAC]) in patients with AF. Method: The authors investigated the persistence of oral anticoagulant (OAC = VKA/NOAC) in atrial fibrillation using the National Health Insurance Fund of Hungary prescriptions database on pharmacy claims between June 1, 2016 and December 31, 2016. Results: 122 870 patients met the inclusion criteria. 18 650 patients started OACs therapy newly (therapy-naïve group), while 104 220 were already on one of the OACs. Among new patients, the one-year persistence of NOACs was 65.7% and that of VKA was 39.0% (p<0.001). The one-year persistence rate was 72.6% for NOAC and 53.9% for VKA (p<0.001) in patients already on OACs. In the therapy-naïve group, the one-year persistence to rivaroxaban was 65.7%. To apixaban it was 62.6%, and to dabigatran it was 59.2% (logrank p<0.001 in all comparisons except rivaroxaban vs. apixaban: p = 0.017, and dabigatran vs. apixaban: p<0.01). The one-year persistence rate of patients treated with NOACs was 73.4% to rivaroxaban, 68.0% to apixaban, and 68.4% to dabigatran (logrank p<0.001 in all comparisons except apixaban vs. dabigatran, NS). Conclusions: The one-year persistence of NOACs was significantly higher in AF compared to VKA therapy (in therapy-naïve and in already treated patients, too). Among the NOACs, rivaroxaban has the best one-year persistence in all patient populations. Orv Hetil. 2020; 161(20): 839-845.

Examining the evidence for PFO closure and novel oral anticoagulants for treatment of cryptogenic stroke

Introduction: There has been considerable study assessing the treatment of cryptogenic stroke (CS) recently. This review examines the role of patent foramen ovale (PFO) closure in CS, while also discussing the evidence for alternative medical therapies in disease treatment.Areas covered: PFO closure for treatment of CS has been assessed in 6 randomized controlled trials (RCTs). This review summarizes the background, results and limitations of these trials. Methodological and treatment-related differences in RCTs provide potential explanations for the discordance in outcomes observed between older (CLOSURE, PC, RESPECT-Early) and newer PFO closure trials (RESPECT-Late, CLOSE, REDUCE, DEFENSE-PFO). With regards to medical therapy for CS, two RCTs (NAVIGATE ESUS and RE-SPECT ESUS) did not show any benefit in recurrent stroke prevention with the use of novel oral anticoagulants (NOAC) compared with aspirin. Marked differences in baseline characteristics and rates of recurrent stroke between PFO closure and NOAC trials underlie the heterogeneous nature of CS.Expert commentary: In young patients with CS, PFO closure reduces the risk of recurrent stroke, with newer RCTs emphasizing the importance of identifying those with 'high-risk' PFO and the need for continued antiplatelet therapy. Additionally, treatment for CS should not be uniform but directed at disease-specific pathologies.

Healthcare resource utilization and expenditures among newly-diagnosed elderly non-valvular atrial fibrillation patients initiating oral anticoagulants

Aims: Non-valvular atrial fibrillation (NVAF) prevalence increases with age. Hence, evaluating the economic burden among older-aged patients is vital. This study aimed to compare healthcare resource utilization (HRU) and costs among newly-diagnosed older-aged NVAF patients treated with warfarin, rivaroxaban, or apixaban vs. dabigatran.Materials and Methods: Newly-diagnosed older-aged (aged ≥65 years) NVAF patients initiating dabigatran, warfarin, rivaroxaban, or apixaban (first prescription date = index date) from 01JAN2010-31DEC2015 and with continuous enrollment for ≥12 months pre-index date were included from 100% Medicare database. Patient data were assessed until drug discontinuation/switch/dose change/death/disenrollment/study end (up to 12 months). Dabigatran initiators were 1:1 propensity score-matched (PSM) with warfarin, rivaroxaban, or apixaban initiators. Generalized linear models were used to compare all-cause HRU and costs per-patient-per-month (PPPM) between the matched cohorts.Results: After PSM with dabigatran, 70,531 warfarin, 51,673 rivaroxaban, and 25,209 apixaban patients were identified. Dabigatran patients had significantly fewer generalized-linear-model-adjusted PPPM hospitalizations (0.114 vs. 0.123; 0.111 vs. 0.121), and outpatient visits (2.864 vs. 4.201; 2.839 vs. 2.949) than warfarin and rivaroxaban patients, respectively, but had significantly more PPPM hospitalizations (0.103 vs. 0.090) and outpatient visits (2.780 vs. 2.673) than apixaban patients (all p < .0001). Dabigatran patients incurred significantly lower adjusted total PPPM costs ($3,309 vs. $3,362; $3,285 vs. $3,474) than warfarin and rivaroxaban patients, respectively (all p < .01) but higher total PPPM costs ($3,192 vs. $2,986) than apixaban patients (all p < .0001).Limitations: This study is subject to the inherent limitations of any claims dataset, including potential bias from coding errors and identification of medical conditions using diagnosis codes as opposed to clinical evidence. Medications filled over-the-counter or provided as samples by the physician are never captured in claims data.Conclusions: Newly-diagnosed older-aged NVAF patients initiating dabigatran incurred significantly lower adjusted all-cause HRU and costs than warfarin and rivaroxaban patients but higher adjusted HRU and costs than apixaban patients.

"A Tale of Two Cities": Anticoagulation Management in Patients with Atrial Fibrillation and Prosthetic Valves in the Era of Direct Oral Anticoagulants

Valvular heart disease and atrial fibrillation often coexist. Oral vitamin K antagonists have represented the main anticoagulation management for antithrombotic prevention in this setting for decades. Novel direct oral anticoagulants (DOACs) are a new class of drugs and currently, due to their well-established efficacy and security, they represent the main therapeutic option in non-valvular atrial fibrillation. Some new evidences are exploring the role of DOACs in patients with valvular atrial fibrillation (mechanical and biological prosthetic valves). In this review we explore the data available in the medical literature to establish the actual role of DOACs in patients with valvular heart disease and atrial fibrillation.

Rivaroxaban in atrial fibrillation cardioversion: an update

Currently, atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, with a prevalence of about 2–3% in the general population, representing a powerful risk factor for stroke and systemic thromboembolism and increased mortality and morbidity. Restoration of sinus rhythm is an important treatment option in AF and has a high success rate, but there is the need for an effective anticoagulation strategy to reduce the risk of embolic events. Anticoagulation with vitamin K antagonists is often associated with failure to achieving effective international normalized ratio. In this setting, recent data have led to extended approval for rivaroxaban in clinical practice, because it is effective and safe in patients with AF undergoing cardioversion, avoiding additional health costs and related time loss, while improving patient satisfaction. The present report provides an overview of the main randomized controlled trial and the main real-life studies, documenting the use of rivaroxaban in patients with non-valvular AF who underwent the cardioversion procedure. Considering that novel non-vitamin K antagonist oral anticoagulants in left atrial appendage thrombi resolution is still unknown in the real-world practice, the main findings on the use of rivaroxaban in this setting are also discussed.

Time-driven activity-based cost analysis for outpatient anticoagulation therapy: direct costs in a primary care setting with optimal performance

OBJECTIVES

To determine how overall cost of anticoagulation therapy for warfarin compares with that of Novel Oral Anticoagulants (NOACs). Also, to demonstrate a scientific, comprehensive, and an analytical approach to estimate direct costs involved in monitoring and management of anticoagulation therapy for outpatients in an academic primary care clinic setting, post-initiation of therapy.

METHODS

A population-based cross-sectional study was conducted in conjunction with observations of patient care processes between August 2014 and January 2015. The study was conducted in an academic primary care outpatient setting at Mayo Clinic's warfarin anticoagulation clinic, Rochester, MN. The anticoagulation clinic serves patients 18 years of age or older in Warfarin therapy management, for any indication, after referral from the patient's primary care provider. The study included anticoagulation clinic enrollment data on a population of 5,526 patients. Time-Driven Activity-Based Costing (TDABC) technique was applied. Detailed process flow maps which showed process steps for all the anticoagulation program components and care continuum phases were created. Staff roles associated with each of the process steps were identified and displayed on the maps. Process times and costs were captured and analyzed. The main outcome was direct cost of monitoring and management of anticoagulation therapy, post-initiation of therapy.

RESULTS

The cost of warfarin management for patients who display unstable International Normalized Ratio (INR) is more than three times those who display stable INR over time. (Comparator to distinguish stability: Frequency of point-of-care visits needed by patients.) For complex anticoagulation patients, total cost of medication and monitoring for warfarin anticoagulation therapy is similar to that for NOACs.

CONCLUSION

Despite warfarin being significantly less expensive to purchase than NOACs, overall warfarin management incurs higher costs due to laboratory monitoring and provider time than NOACs. NOAC treatment, therefore, may not be more expensive than warfarin therapy management for complex anticoagulation patients.

[One-year persistence of patients already treated with oral anticoagulants for atrial fibrillation]

INTRODUCTION

In the treatment of non-valvular atrial fibrillation (AF) with oral anticoagulants (OAC), medical adherence is a relevant factor for stroke prevention.

AIM

To evaluate the one-year persistence of vitamin K antagonists (VKA) and direct oral anticoagulants (DOAC) in patients suffering from AF and already treated with OACs.

METHOD

Information from the National Health Insurance Fund of Hungary prescriptions database on pharmacy claims between June 1, 2015 and December 31, 2015 was analysed. Authors identified patients who filled prescriptions for OACs (VKAs or DOACs) prescribed for AF who have already received OACs therapy during one year before. Apparatus of survival analysis was used, where 'survival' was the time to abandon the medication.

RESULTS

196 016 patients met the inclusion criteria. 181 810 patients received VKA and 14 206 patients were treated with DOACs. The one-year persistence rate in patients taking VKA was 52.9% whereas it was 66.8% in those on the DOACs. The persistence rates after 360 days were 67.5% for rivaroxaban, 63.6% for apixaban and 63.4% for dabigatran. The mean duration of persistence was 311 days for rivaroxaban, 308 days for apixaban and 284 days for dabigatran. The actual rate of discontinuation was 14% (HR = 1.14 [95% CI 1.05-1.24]), p = 0.0015) for apixaban, 15% (HR = 1.15 [95% CI 1.08-1.23], p = 0.003) for dabigatran and 62% (HR = 1.62 [95% CI 1.56-1.69], p<0.0001) for VKA compared to rivaroxaban (reference).

CONCLUSIONS

The authors have confirmed that the one-year persistence of DOAKs was significantly higher compared to KVA therapy in AF. The one-year persistence of rivaroxaban was more favoured than apixaban and dabigatran. Orv Hetil. 2019; 160(13): 509-515.

Thrombolysis in an acute ischemic stroke patient with rivaroxaban anticoagulation: A case report

RATIONALE

Whether intravenous recombinant tissue plasminogen activator (r-TPA) therapy can be administered in acute ischemic stroke patients treated with novel oral anticoagulants (NOACs), including rivaroxaban, remains controversial.

PATIENT CONCERNS

A 76-year-old woman with nonvalvular atrial fibrillation, who had been receiving 15 mg rivaroxaban once daily, was brought to the emergency department with right-side hemiparesis and aphasia. The onset of neurological deficits occurred 8 hours after the last dose of rivaroxaban administration.

DIAGNOSIS

The patient was diagnosed with acute ischemic stroke.

INTERVENTIONS

Intravenous infusion of 0.6 mg/kg of r-TPA (total dose: 29 mg) was performed 9 hours and 40 minutes after the last rivaroxaban administration. During r-TPA infusion, improvement in the patient's neurological deficit was observed.

OUTCOMES

The clinical picture evidently improved from with National Institutes of Health Stroke Scale 21 to 16 on completion of r-TPA treatment.

LESSONS

Although current guidelines do not recommend administering thrombolytics in patients using NOACs with a doubtful anticoagulation status and administered within the last 24 or, even more strictly, 48 hours, this and other case studies suggest that r-TPA treatment could be considered in selected acute ischemic stroke patients receiving rivaroxaban or other Xa inhibitors, taking the patient's clinical condition and the prospective clinical benefits of r-TPA into account.

Dabigatran as an alternative for atrial thrombosis resistant to rivaroxaban: A case report

RATIONALE

Anti-thrombosis therapy for atrial fibrillation (AF) management and stroke prevention is an important aspect of disease management. Novel oral anticoagulants (NOACs) are recommended by guidelines for AF management. However, if one can switch one NOAC to another when the former showed a poor effect has not been fully determined.

PATIENT CONCERNS

A 52-year-old man was admitted to our center for heart failure and AF with a thrombus in the left atrium.

DIAGNOSES

Cardiomyopathy was diagnosed by cardiac magnetic resonance (CMR) and echocardiography.

INTERVENTIONS

He was prescribed rivaroxaban (20 mg daily) as treatment, and dabigatran (150 mg twice daily) was used when the thrombus was found to be non-response to rivaroxaban.

OUTCOMES

The rivaroxaban did not diminish the atrial thrombus, and dabigatran was given instead which finally eliminated the thrombus.

LESSONS

Individualized responsiveness to NOACs should be considered and paid more attention to during clinical practice.

Anticoagulation in the cardiac patient: A concise review

Anticoagulation has multiple roles in the treatment of cardiovascular disease, including in management of acute myocardial infarction, during percutaneous coronary intervention, as stroke prophylaxis in patients with atrial arrhythmias, and in patients with mechanical heart valves. Clinical anticoagulation choices in the aforementioned diseases vary widely, due to conflicting data to support established agents and the rapid evolution of evidence-based practice that parallels more widespread use of novel oral anticoagulants. This review concisely summarizes evidence-based guidelines for anticoagulant use in cardiovascular disease, and highlights new data specific to direct oral anticoagulants.

Advances and Application of a Novel Oral Anticoagulant in Specific Populations: Dabigatran Etexilate

BACKGROUND

Dabigatran etexilate (DE) was approved by the FDA in 2010 to reduce the risk of stroke and systemic embolism in adults with Non-valvular Atrial Fibrillation (NVAF). Compared with warfarin, a traditional anticoagulant drug, DE exhibits a shorter half-life, improved dose-effect relationship, fewer food and drug interactions, and can be taken orally without monitoring the conventional coagulation index. DE can also prevent or reduce the severity of adverse events, such as attenuated drug efficacy or bleeding. It is convenient for patients to take DE due to low levels of individual variation. This review aims to application of Dabigatran etexilate in specific populations.

METHODS

Fifty-five papers were included in the review.

RESULTS

We review the pharmacological mechanisms, pharmacokinetics and drug interactions, as well as the application of DE for different clinical populations, and provide clinical guidelines.

CONCLUSION

When using DE, one should consider the risk of bleeding, age, renal function, drug interactions, and other factors.

Safety and effectiveness of apixaban in comparison to warfarin in patients with nonvalvular atrial fibrillation: a propensity-matched analysis from Japanese administrative claims data

OBJECTIVE

To investigate the risk of bleeding events and stroke/systemic embolism (SE) among Japanese patients with nonvalvular atrial fibrillation (NVAF), focusing on the initial dosage of apixaban and patient age.

METHODS

This retrospective cohort study used de-identified electronic health records based claims data from 314 acute-care hospitals in Japan. NVAF patients newly initiated on warfarin or apixaban, with no prescription during the 180-day blanking period, were eligible. Patients were allocated to receive warfarin or 5 or 2.5 mg twice daily (BID) apixaban. One-to-one propensity-score matching was used to balance patient characteristics between apixaban and warfarin.

RESULTS

Among 31,006 eligible patients, 11,972 matched pairs were identified for apixaban versus warfarin. Mean age ± standard deviation was 77.7 ± 10.0 and 77.6 ± 10.0 years and CHADS₂ score was 2.2 ± 1.4 and 2.2 ± 1.4 for warfarin and apixaban, respectively. In the apixaban cohort, 39.4% of patients received the standard dose (5 mg BID) and 60.6% received the reduced dose (2.5 mg BID). Incidence rates (events per 100 person-years) of major bleeding, any bleeding and stroke/SE were 3.7, 23.1 and 3.1, and 2.5, 18.6 and 2.0 for warfarin and apixaban cohorts, respectively. Apixaban was associated with a significantly lower risk of any bleeding (hazard ratio [HR] 0.809, 95% confidence interval [CI] 0.731-0.895; p < .001), major bleeding (HR 0.655, 95% CI 0.505-0.849; p = .001) and stroke/SE (HR 0.637, 95% CI 0.478-0.850; p = .002).

CONCLUSIONS

Our observational data from clinical practice broadly confirms the safety and efficacy results of pivotal randomized controlled trials of apixaban for stroke prevention among NVAF patients.

Successful Application of Edoxaban in the Treatment of Venous Thromboembolism Recurrence in a Patient with Non-small Cell Lung Cancer after Tumor Shrinkage

This report describes the case of a 66-year-old man with non-small cell lung cancer and venous thromboembolism (VTE). Unfractionated heparin (UFH) was initially used to control VTE before chemotherapy. However, switching UFH to warfarin or edoxaban, a novel oral anticoagulant (NOAC), failed. Chemotherapy was then administered to control the tumor which was thought to have been the main cause of VTE, which had been treated by UFH. After tumor shrinkage was achieved by chemotherapy, we were able to successfully switch from UFH to edoxaban. Controlling the tumor size and activity enabled the use of edoxaban as maintenance therapy for VTE.

Pharmacogenetics of novel oral anticoagulants: a review of identified gene variants & future perspectives

Novel oral anticoagulants (NOACs) are becoming a therapy of choice in everyday clinical practice after almost 50 years during which warfarin and related coumarin derivatives were used as the main anticoagulants. Advantages of NOACs over standard anticoagulants include their predictable pharmacodynamics and pharmacokinetics, stable plasma concentrations and less drug-drug and food-drug interactions. However, pharmacogenetics has its place in administration of NOACs, as considerable interindividual variations have been detected. In this review, previous findings in pharmacogenetics of dabigatran, rivaroxaban, apixaban and edoxaban are summarized, along with recommendations for studying genes encoding metabolically important enzymes for four selected NOACs. Future directions include identification of clinically relevant SNPs, and change in optimum dosage for patients who are carriers of significant variants.

Assessing an oral surgery specific protocol for patients on direct oral anticoagulants: a retrospective controlled cohort study

Chronic therapy with the new direct oral anticoagulants (DOACs) poses new challenges for dental practitioners assessing the risk versus benefit of cessation versus non-cessation of anticoagulant therapy for dentoalveolar procedures. A retrospective controlled cohort study was designed to evaluate a non-cessation protocol for patients taking DOACs in the setting of dental extractions. A records review covering the period 1 January 2016 to 31 December 2016 identified 43 patients on DOAC therapy; 53 dentoalveolar procedures were performed under local anaesthesia, of which 15 included varying degrees of peri-procedural cessation. A control group of 50 patients on uninterrupted warfarin therapy undergoing 59 dentoalveolar procedures was identified. The incidence, severity, and timing of bleeding events were recorded for each group. Four (10.5%) minor bleeding events were recorded in the non-cessation DOAC group and nine (15.3%) minor bleeding events in the warfarin group. No bleeding events were recorded in the DOAC cessation group. Comparison of the incidence of bleeding events between the non-cessation DOAC group and the warfarin group showed no statistically significant difference (odds ratio 0.65, P=0.56). Within the limitations of this study, dental extractions in the context of continuing DOAC therapy can be performed safely provided extra local haemostatic measures are applied.

Lesson of the month 2: A rare presentation of stroke: diagnosis made on magnetic resonance imaging

Bilateral thalamic infarcts are uncommon posterior circulation strokes. The artery of Percheron (AOP) is a rare anatomical variant involving a singular arterial supply to both thalami and occlusion leads to bilateral thalamic infarction.We report the case of a 71-year-old man who presented with decreased consciousness (fluctuating Glasgow Coma Scale score of 5-7). He had a background of atrial fibrillation and was anticoagulated with dabigatran, a novel oral anticoagulant. Computed tomography (CT) scan showed a mildly reduced attenuation in the region of the left thamalus.Subsequent diffusion-weighted magnetic resonance imaging (MRI) showed acute brainstem infarction, extending into the thalamus bilaterally, likely due to AOP occlusion. Bilateral thalamic infarcts due to AOP occlusion may not be recognised on initial CT scan and are more readily seen using diffusion-weighted MRI, which is the most beneficial imaging modality to aid in early diagnosis and treatment.

Contemporary utilization of antithrombotic therapy for stroke prevention in patients with atrial fibrillation: an audit in an Australian hospital setting

BACKGROUND

To document antithrombotic utilization in patients with nonvalvular atrial fibrillation (NVAF), particularly, recently approved NOACs (nonvitamin K antagonist oral anticoagulants) and warfarin; and identify factors predicting the use of NOACs versus warfarin.

METHODS

A retrospective audit was conducted in an Australian hospital. Data pertaining to inpatients diagnosed with atrial fibrillation (AF) admitted between January and December 2014 were extracted. This included patient demographics, risk factors (stroke, bleeding), social history, medical conditions, medication history, medication safety issues, medication adherence, and antithrombotic prescribed at admission and discharge.

RESULTS

Among 199 patients reviewed, 84.0% were discharged on antithrombotics. Anticoagulants (± antiplatelets) were most frequently (52.0%) prescribed (two-thirds were prescribed warfarin, the remainder NOACs), followed by antiplatelets (33.0%). Among 41 patients receiving NOACs, 59.0% were prescribed rivaroxaban, 24.0% dabigatran, and 17.0% apixaban. Among patients aged 75 years and over, antiplatelets were most frequently used (37.0%), followed by warfarin (33.0%), then NOACs (14.0%). Compared with their younger counterparts, patients aged 75 years and over were significantly less likely to receive NOACs (14.0% versus 28.0%, p = 0.01). Among the 'most eligible' patients (Congestive Cardiac Failure, Hypertension (, Age ⩾ 75 years, Age= 65-74 years, Diabetes Mellitus, Stroke/ Transient Ischaemic Attack/ Thromboembolism, Vascular disease, Sex female[CHA2DS2-VASc] score ⩾2 and no bleeding risk factors), 46.0% were not anticoagulated on discharge. Patients with anaemia (68.0% versus 86.0%, p = 0.04) or a history of bleeding (65.0% versus 87.0%, p = 0.01) were less likely to receive antithrombotics compared with those without these risk factors. Warfarin therapy was less frequently prescribed among patients with cognitive impairment compared with patients with no cognitive issues (12.0% versus 23.0%, p = 0.01). Multivariate logistic regression modelling identified that patients with renal impairment were 3.6 times more likely to receive warfarin compared with NOACs (odds ratio = 3.6, 95% confidence interval = 0.08-0.90, p = 0.03, 60.0% correctly predicted; Cox and Snell R2 = 0.51, Nagelkerke R2 = 0.69).

CONCLUSION

Despite the availability of NOACs, warfarin remains a preferred treatment option, particularly among patients with renal impairment. The high proportion of eligible patients still being prescribed antiplatelet therapy or 'no therapy' needs to be addressed.

Comparative effectiveness of novel oral anticoagulants in UK patients with non-valvular atrial fibrillation and chronic kidney disease: a matched cohort study

OBJECTIVES

To evaluate the effectiveness and safety of novel oral anticoagulants (NOACs) compared with vitamin K antagonists (VKAs) among patients with non-valvular atrial fibrillation (NVAF), particularly those with chronic kidney disease (CKD).

DESIGN

Population-based matched cohort study.

SETTING

Over 670 primary care practices in the UK, contributing to the Clinical Practice Research Datalink.

PARTICIPANTS

Up to 6818 adult patients newly treated with NOACs between 2011 and 2016, matched 1:1 to new users of VKAs on age, sex and high-dimensional propensity score.

INTERVENTIONS

Current exposure to NOACs compared with current exposure to VKAs.

MAIN OUTCOME MEASURES

HRs of ischaemic stroke and systemic embolism (SE), major bleeding, gastrointestinal (GI) bleeding, intracranial bleeding, myocardial infarction and all-cause mortality.

RESULTS

In as-treated analyses, the rates of ischaemic stroke/SE were similar between NOACs and VKAs (HR 0.94; 95% CI 0.62 to 1.42), as were the rates of major bleeding (HR 0.86; 95% CI 0.56 to 1.33). NOACs also significantly increased the risk of GI bleeding (HR 1.78; 95% CI 1.27 to 2.48). In patients with NVAF and CKD, NOACs and VKAs remained comparable with respect to the risk of ischaemic stroke/SE (HR 0.79; 95% CI 0.40 to 1.58) and major bleeding (HR 0.88; 95% CI 0.47 to 1.62), with no difference in the risk of GI bleeding (HR 0.99; 95% CI 0.63 to 1.55). Similar results were obtained in on-treatment analyses using a time-dependent exposure definition.

CONCLUSIONS

Our results suggest that in the UK primary care, NOACs are overall effective and safe alternatives to VKAs, among patients with NVAF altogether, as well as in patients with NVAF and CKD.

Anticoagulation in Patients with Ischaemic Heart Disease and Peripheral Arterial Disease: Clinical Implications of COMPASS Study

Patients with established cardiovascular disease may suffer further cardiovascular events, despite receiving optimal medical treatment. Although platelet inhibition plays a central role in the prevention of new events, the use of anticoagulant therapies to reduce events in atheromatous disease has, until recently, been overlooked. The recent Rivaroxaban for the Prevention of Major Cardiovascular Events in Coronary or Peripheral Artery Disease (COMPASS) study showed an important reduction in cardiovascular events without increasing the risk of fatal and intracranial bleeding when using rivaroxaban, a novel oral anticoagulant, combined with aspirin. This article reviews the available evidence regarding the use of anticoagulant therapies for prevention of cardiovascular events, the results of the COMPASS study and how these results may affect patient management in everyday clinical practice.

Safety and efficacy of rivaroxaban for the secondary prevention following acute coronary syndromes among biomarker-positive patients: Insights from the ATLAS ACS 2-TIMI 51 trial

BACKGROUND:

Despite dual antiplatelet therapy, persistent thrombin generation and thrombin-mediated platelet activation account in part for the residual risk of atherothrombotic disease among patients with prior acute coronary syndrome (ACS). Inhibition of thrombin generation among high-risk ACS patients (biomarker-positive ACS) with the factor Xa inhibitor rivaroxaban may limit ongoing thrombus formation and myocardial necrosis and thereby improve clinical outcomes.

OBJECTIVES AND METHODS:

ATLAS ACS 2-TIMI 51 was a double-blind, placebo-controlled clinical trial that randomized ACS patients to either rivaroxaban 2.5 mg b.i.d., rivaroxaban 5 mg b.i.d., or placebo plus standard-of-care antiplatelet therapy for a mean of 13.1 months and up to 31 months ( N=15,526). This post-hoc analysis evaluates the safety and efficacy of rivaroxaban among biomarker-positive ACS patients with and without a history of prior stroke of transient ischemic attack in the ATLAS ACS 2-TIMI 51 trial.

RESULTS:

A total of 12,626 biomarker-positive ACS patients were included in this analysis. Among biomarker-positive patients without a prior history of stroke or transient ischemic attack, rivaroxaban 2.5 b.i.d. was associated with a reduction in the primary efficacy endpoint (composite of cardiovascular death, myocardial infarction, or stroke) as compared with placebo (hazard ratio=0.80, 95% confidence interval (0.68-0.94), p=0.007) at the expense of an increase in non-coronary-artery-bypass-graft-related Thrombolysis in Myocardial Infarction major bleeding (1.9% vs. 0.7%, p<0.0001), but not a significant increase in either intracranial hemorrhage (0.4% vs. 0.2%, p=0.11) or fatal bleeding (0.1% vs. 0.3%, p=0.16).

CONCLUSION:

Rivaroxaban 2.5 mg b.i.d. was associated with a significant reduction in the composite of cardiovascular death, myocardial infarction, or stroke with no increase in fatal bleeding. Biomarker-positive patients with no prior history of stroke or transient ischemic attack may be a optimal target population to receive "dual pathway" therapy with rivaroxaban plus dual antiplatelet therapy for secondary prevention following ACS.

Bleeding risk of apixaban, dabigatran, and low-dose rivaroxaban compared with warfarin in Japanese patients with non-valvular atrial fibrillation: a propensity matched analysis of administrative claims data

OBJECTIVES

There is scarce evidence comparing novel oral anticoagulants (NOACs) with warfarin in real-world settings in Japan. This study compared the risk of bleeding events among patients with non-valvular atrial fibrillation (NVAF) initiating treatment with NOACs versus warfarin.

METHODS

A retrospective cohort study was conducted using a de-identified electronic health record based database of health claims and Diagnosis Procedure Combination data from 275 consenting hospitals in Japan. NVAF patients newly initiated on oral anticoagulants were eligible. Based on the first prescription, patients were assigned to 5/2.5 mg BID apixaban, 150/110 mg BID dabigatran, 15/10 mg QD rivaroxaban (approved dose lower in Japan compared to Western countries [20/15 mg QD]) or warfarin groups. One-to-one propensity score matching (PSM) was used to balance patient characteristics between warfarin and each NOAC. Patients were followed up to 1 year post-first prescription.

RESULTS

Among 38,662 eligible patients, a total of 5977, 5090, and 6726 matched pairs were identified for warfarin versus apixaban, warfarin versus dabigatran, and warfarin versus rivaroxaban, respectively after PSM. Compared to warfarin, apixaban (hazard ratio [HR] 0.586; 95% CI 0.421-0.815), dabigatran (HR 0.617; 0.425-0.895) and rivaroxaban (HR 0.693; 0.514-0.933) were associated with a significantly lower risk of major bleeding. The risk of any bleeding was significantly lower for apixaban (HR 0.782; 0.682-0.896), but not for dabigatran (HR 0.988; 0.860-1.135) or rivaroxaban (HR 0.938; 0.832-1.057) when comparing to warfarin.

CONCLUSIONS

Among Japanese patients with NVAF, treatment with apixaban 5/2.5 mg BID was associated with a significantly lower risk of major bleeding and any bleeding when compared to warfarin. Treatment with dabigatran 150/110 mg BID or rivaroxaban 15/10 mg QD was associated with a significantly lower risk of major bleeding, but not any bleeding, than warfarin. The potential benefit of individual NOACs in real-world practice needs to be assessed further.

Resolution of intracardiac thrombus with novel oral anticoagulants in an adult patient with complex CHD

Thromboembolic complications occur frequently in Fontan patients with atrial arrhythmias and are a cause of significant morbidity and all-cause mortality. We report the case of an adult woman with direct atriopulmonary connection and atrial arrhythmia who developed a right atrial thrombus. She was switched to apixaban therapy because of echocardiographic evidence of thrombus progression despite combined therapy with warfarin and aspirin. After 1 year of treatment, there was evidence of complete thrombus resolution, in the absence of bleeding events. Our case shows that direct oral anticoagulants can be effective and safe for the treatment of thrombosis in adult patients with complex CHD.

Influence of novel oral anticoagulants on anticoagulation care management

Anticoagulation treatment was recently improved by the introduction of novel oral anticoagulants (NOACs). Using a combination of qualitative and quantitative methods, this study explores the effects of the introduction of NOACs on anticoagulation care in Slovenia. Face-to-face interviews with key stakeholders revealed evolvement and challenges of anticoagulation care from different perspectives. Obtained information was further explored through the analysis of nationwide data of drug prescriptions and realization of health care services. Simplified management of anticoagulation treatment with NOACs and their high penetration expanded the capacity of anticoagulation clinics, and consequentially the treated population increased by more than 50 % in the last 5 years. The main challenge concerned the expenditures for medicines, which increased approximately 10 times in just a few years. At the same time, the anticoagulation clinics and their core organisation were not affected, which is not expected to change, since they are vital in delivering high-quality care.

Using an Atrial Fibrillation Decision Support Tool for Thromboprophylaxis in Atrial Fibrillation: Effect of Sex and Age

OBJECTIVES

To assess the appropriateness of oral anticoagulant therapy (OAT) in women and elderly adults, looking for patterns of undertreatment or unnecessary treatment.

DESIGN

Retrospective cohort study.

SETTING

Primary care practices of an academic healthcare system.

PARTICIPANTS

Adults (aged 28-93) with nonvalvular atrial fibrillation (AF) seen between March 2013 and February 2014 (N = 1,585).

MEASUREMENTS

Treatment recommendations were made using an AF decision support tool (AFDST) based on projections of quality-adjusted life expectancy calculated using a decision analytical model that integrates individual-specific risk factors for stroke and hemorrhage.

RESULTS

Treatment was discordant from AFDST-recommended treatment in 45% (326/725) of women and 39% (338/860) of men (P = .02). Although current treatment was discordant from recommended in 35% (89/258) of participants aged 85 and older and in 43% (575/1,328) of those younger than 85 (P = .01), many undertreated elderly adults were receiving aspirin as the sole antithrombotic agent.

CONCLUSION

Physicians should understand that female sex is a significant risk factor for AF-related stroke and incorporate this into decision-making about thromboprophylaxis. Treating older adults with aspirin instead of OAT exposes them to significant risk of bleeding with little to no reduction in AF-related stroke risk.