Advancing age and bleeding risk are the strongest barriers to anticoagulant prescription in atrial fibrillation

Appropriate Use Criteria of Left Atrial Appendage Closure Devices: Latest Evidences

Atrial fibrillation is the most common arrythmia and it is linked to an increased risk of stroke. Even if anticoagulation therapy reduces the rate of stroke the benefits of this therapy have to been balanced with the increased risk of hemorrhagic event. Left atrial appendage closure is a valid alternative to long term anticoagulation in patients with atrial fibrillation and high hemorrhagic risk. Actually new devices with different features have been tested and introduced progressively in the clinical practice. Improvements preprocedural imaging evaluation and the learning curve of the operators led to percutaneous left atrial appendage closure a safe and effective procedure. A good knowledge of different devices and the technique of implant is necessary for optimization percutaneous left atrial appendage closure and the reduction of complications during the acute phase and follow up.

Antithrombotic strategy variability in atrial fibrillation and obstructive coronary disease revascularised with percutaneous coronary intervention: primary results from the AVIATOR 2 international registry

BACKGROUND

Managing percutaneous coronary intervention (PCI) patients with atrial fibrillation (AF) presents challenges given that there are several potential antithrombotic therapy (ATT) strategies.

AIMS

We examined ATT patterns, agreement between subjective physician ratings and validated risk scores, physician-patient perceptions influencing ATT and 1-year outcomes.

METHODS

The AVIATOR 2 prospective registry enrolled 514 non-valvular AF-PCI patients from 11 sites. Treating physicians selected ATT and completed smartphone surveys rating stroke and bleeding risks, compared against CHA2DS2-VASc and HAS-BLED scores. Patients completed surveys regarding treatment understanding. Primary outcomes were 1-year major adverse cardiac or cerebrovascular events (MACCE: composite of death, myocardial infarction, definite/probable stent thrombosis, stroke, target lesion revascularisation) and actionable bleeding (Bleeding Academic Research Consortium 2, 3 or 5).

RESULTS

The mean patient age was 73.2±9.0 years, including 25.8% females. Triple therapy (TT: 1 anticoagulant and 2 antiplatelet agents) was prescribed in 66.5%, dual antiplatelet therapy (DAPT) in 20.7% and dual therapy (1 anticoagulant+1 antiplatelet agent) in 12.8% of patients. Physician ratings and validated risk scores showed poor agreement (stroke: kappa=0.03; bleeding: kappa=0.07). Physicians rated bleeding-related safety (93.8%) as the main factor affecting ATT choice. Patients worried about stroke over bleeding (50.6% vs 14.8%). No group differences by ATT strategy were observed in 1-year MACCE (TT 14.1% vs dual therapy 12.7% vs DAPT 18.5%; p=0.25), or actionable bleeding (14.7% vs 7.9% vs 15.1%, respectively; p=0.89).

CONCLUSIONS

The AVIATOR 2 study is the first digital health study examining physician-patient perspectives on ATT choices after AF-PCI. TT was the most common strategy without differences in 1-year outcomes in ATT strategy. Physicians rated safety first when prescribing ATT; patients feared stroke over bleeding.

CLINICALTRIALS

gov: NCT02362659.

Age associated non-linear regulation of redox homeostasis in the anucleate platelet: Implications for CVD risk patients

Background

Aging is a complex physiological phenomenon, intricately associated with cardiovascular pathologies, where platelets play a central pathophysiological role. Although antiplatelets are commonly employed to prevent and treat major adverse cardiovascular events, aging associated intraplatelet changes remain largely unexplored.

Methods

Platelets were studied in high cardiovascular risk patients (aged 40–100 years) comparing them to younger healthy subjects. This was followed by cross sectional and longitudinal mice studies. Flow cytometry, biochemical and molecular assays were used to study platelets comprehensively.

Findings

CVD Patients were categorized in the age groups 40–59, 60–79, and 80–100 years. Progressive decline in platelet health was observed in the 40–79 years age cohort, marked by increase in oxidative stress, hyperactivation and apoptotic markers. Paradoxically, this was reversed in patients aged above 79 years and the improved platelet phenotype was associated with lower oxidative damage. The platelets from the very old (80–100 year) group were found to be preloaded with increased antioxidants, which also contributed to higher resistance against induced redox insults. Cross sectional mouse studies excluded the effect of comorbidities and medications. Longitudinal mouse studies implicate an adaptive increase in antioxidant levels as the mechanism.

Interpretation

We report a novel age associated, non-linear redox regulation in platelets in both humans and mice. In advanced age, there occurs an adaptive increase in platelet antioxidants, reducing the intracellular ROS and leading to a healthier platelet phenotype. Clinically, our results advocate the use of less aggressive antiplatelet therapies for CVD in the elderly population.

Fund

Study funded by NIH-NHLBI, RO1-HL122815 and RO1-HL115247.

Stroke risk reduction outweighed bleeding risk increase from vitamin K antagonist treatment among nonvalvular atrial fibrillation patients with high stroke risk and low bleeding risk

OBJECTIVE

Warfarin is widely used for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF). We compared the rates of stroke and major bleeding in NVAF patients with a high stroke risk and low bleeding risk profile during warfarin treated (W+) and warfarin untreated (W-) periods.

METHOD

Insurance claims from six commercial, Medicaid or Medicare databases were analyzed from 2000 to 2014. NVAF patients treated with warfarin, with a CHADS₂/CHA₂DS₂-VASc score ≥2, and an ATRIA score ≤3 at baseline were identified. Incidence rate ratios (IRRs) of stroke and major bleeding were calculated for W + versus W- episodes of person-time, as well as for first 30 days versus beyond 30 days of W + episodes.

RESULTS

Among 316,145 patients, anticoagulant prophylaxis with warfarin significantly reduced stroke risk, with IRRs ranging from 0.48 (95% CI: 0.46-0.51) to 0.80 (95% CI: 0.70-0.91), and increased major bleeding risk, with IRRs ranging from 1.13 (95% CI: 1.10-1.15) to 1.95 (95% CI: 1.10-3.45). Stroke and major bleeding rates were higher during the first 30 days of W + than beyond.

CONCLUSION

In NVAF patients at high risk for stroke and low risk for bleeding, our data confirm the effectiveness of anticoagulation for stroke prevention. The decrease in stroke risk of anticoagulation may outweigh the risk of major bleeding events, particularly among elderly patients. Potential risks of warfarin during initiation warrant attention, especially among patients who stop and start therapy repeatedly.

Decision-making around antithrombotics for stroke prevention in atrial fibrillation: the health professionals' views

Background For stroke prevention in patients with atrial fibrillation (AF), the decision-making around antithrombotic therapy has been complicated by older age, multiple comorbidities, polypharmacy and the different pharmacological properties of warfarin and the nonvitamin K antagonist oral anticoagulants (NOACs). The complexity of decision-making has been associated with a reluctance by health professionals to use antithrombotic therapy, leading to poor clinical outcomes. In order to improve stroke prevention in patients with AF, the contemporary perspectives of health professionals on the decision-making around antithrombotic therapy needs exploration. Objective To elicit emerging themes describing health professionals' perspectives on the decision-making around antithrombotic therapy for stroke prevention in patients with AF. Setting Sydney metropolitan area of New South Wales, Australia. Method A qualitative study based on face-to-face interviews was conducted from August to October 2014. Seven pharmacists, seven specialists, six general practitioners and six nurses practising in the Sydney metropolitan area and managing antithrombotic therapy for AF were interviewed until theme saturation was achieved in each subgroup. Interview transcripts were analysed using manual inductive coding. Main outcome measure Emerging themes describing health professionals' perspectives on the decision-making around antithrombotic therapy for stroke prevention in patients with AF. Results Three overarching themes emerged. (1) Comprehensive assessment is necessary for decision-making but is not always implemented. Health professionals mostly focused on stroke risk assessment, not on the bleeding risk and medication safety issues. (2) Health professionals from different disciplines have different preferences for antithrombotic therapies. Although the majority of health professionals considered warfarin as the first-line therapy, NOACs were preferred by neurologists and haematologists. (3) Health professionals focused on different aspects of the decision making process: GPs and specialists were concerned about the appropriate prescription of antithrombotics, while pharmacists and nurses focused on daily medication management by patients. Conclusion The decision-making process appears to be partially preference based rather than systematic, and health professionals from various disciplines focus on different parts of the decision-making process.

Development of a shared decision-making tool to assist patients and clinicians with decisions on oral anticoagulant treatment for atrial fibrillation

OBJECTIVE

Decision aids (DAs) are increasingly used to operationalize shared decision-making (SDM) but their development is not often described. Decisions about oral anticoagulants (OACs) for atrial fibrillation (AF) involve a trade-off between lowering stroke risk and increasing OAC-associated bleeding risk, and consideration of how treatment affects lifestyle. The benefits and risks of OACs hinge upon a patient's risk factors for stroke and bleeding and how they value these outcomes. We present the development of a DA about AF that estimates patients' risks for stroke and bleeding and assesses their preferences for outcomes.

RESEARCH DESIGN AND METHODS

Based on a literature review and expert discussions, we identified stroke and major bleeding risk prediction models and embedded them into risk assessment modules. We identified the most important factors in choosing OAC treatment (warfarin used as the default reference OAC) through focus group discussions with AF patients who had used warfarin and clinician interviews. We then designed preference assessment and introductory modules accordingly. We integrated these modules into a prototype AF SDM tool and evaluated its usability through interviews.

RESULTS

Our tool included four modules: (1) introduction to AF and OAC treatment risks and benefits; (2) stroke risk assessment; (3) bleeding risk assessment; and (4) preference assessment. Interactive risk calculators estimated patient-specific stroke and bleeding risks; graphics were developed to communicate these risks. After cognitive interviews, the content was improved. The final AF tool calculates patient-specific risks and benefits of OAC treatment and couples these estimates with patient preferences to improve clinical decision-making.

CONCLUSIONS

The AF SDM tool may help patients choose whether OAC treatment is best for them and represents a patient-centered, integrative approach to educate patients on the benefits and risks of OAC treatment. Future research is needed to evaluate this tool in a real-world setting. The development process presented can be applied to similar SDM tools.

Novel oral anticoagulants for stroke prevention in the geriatric population

Prior to the availability of several newer anticoagulant medications, there had been no new advances in anticoagulation management for stroke prevention since the advent of warfarin in the 1950s. The availability of the novel oral anticoagulants (NOACs) dabigatran, rivaroxaban,and apixaban represent improvements over warfarin in many respects, including the elimination of the need for therapeutic drug monitoring, fewer drug and food interactions,and favorable efficacy; however, these agents are not without risk. Specifically, the use of the NOACs in the geriatric population, who are more likely to have an increased risk of stroke due to atrial fibrillation and other medical comorbidities, is not without risk. The objective of this review is to update the clinician on the use of the NOACs in the geriatric population and introduce the controversies and risks surrounding these newer therapies.

Automated Risk Assessment for Stroke in Atrial Fibrillation (AURAS-AF)--an automated software system to promote anticoagulation and reduce stroke risk: study protocol for a cluster randomised controlled trial

Background

Patients with atrial fibrillation (AF) are at significantly increased risk of stroke. Oral anticoagulants (OACs) substantially reduce this risk, with gains seen across the spectrum of baseline risk. Despite the benefit to patients, OAC prescribing remains suboptimal in the United Kingdom (UK). We will investigate whether an automated software system, operating within primary care electronic medical records, can improve the management of AF by identifying patients eligible for OAC therapy and increasing uptake of this treatment.

Methods/Design

We will conduct a cluster randomised controlled trial, involving general practices using the Egton Medical Information Systems (EMIS) Web clinical system. We will randomise practices to use an electronic software tool or to continue with usual care. The tool will a) produce (and continually refresh) a list of patients with AF who are eligible for OAC therapy - practices will invite these patients to discuss therapy at the start of the trial - and b) generate electronic screen reminders in the medical records of those eligible, appearing throughout the trial. The software will run for 6 months in 23 intervention practices. A total of 23 control practices will manage their AF register in line with the usual care offered. The primary outcome is change in proportion of eligible patients with AF who have been prescribed OAC therapy after six months. Secondary outcomes are incidence of stroke, transient ischaemic attack, other major thromboembolism, major haemorrhage and reports of inappropriate OAC prescribing in the data collection sample - those deemed eligible for OACs. We will conduct a process evaluation in parallel with the randomised trial. We will use qualitative methods to examine patient and practitioner views of the intervention and its impact on primary care practice, including its time implications.

Discussion

AURAS-AF will investigate whether a simple intervention, using electronic primary care records, can improve OAC uptake in a high risk group for stroke. Given previous concerns about safety, especially surrounding inappropriate prescribing, we will also examine whether electronic reminders safely impact care in this clinical area.

Trial registration

http://ISRCTN 55722437