Risk of myocardial infarction and death in patients with atrial fibrillation treated with dabigatran or vitamin K antagonists

Real-world evidence comparing oral anticoagulants in non-valvular atrial fibrillation: a systematic review and network meta-analysis

Aim: To compare real-world effectiveness/safety of non-vitamin K antagonist oral anticoagulants and vitamin K antagonists among patients with non-valvular atrial fibrillation. Materials & methods: A systematic review of electronic databases yielded 7661 citations published from January 2013 to January 2020. Fifty-five studies were included in Bayesian network meta-analyses of hazard ratios. Results & conclusion: In comparison with vitamin K antagonists, apixaban, dabigatran and rivaroxaban were associated with a reduced risk of stroke or systemic embolism, ischemic stroke, intracranial hemorrhage and all-cause mortality. Apixaban, dabigatran and edoxaban, but not rivaroxaban, were associated with a reduced risk of major bleeding. This study confirmed the effectiveness and safety of non-vitamin K antagonist oral anticoagulants for the treatment of non-valvular atrial fibrillation in real-world settings, consistent with clinical trial evidence.

Long-Term Risk of Major Adverse Cardiac Events in Atrial Fibrillation Patients on Direct Oral Anticoagulants

OBJECTIVE

To determine the association between direct oral anticoagulant (DOAC) use and risk of major adverse cardiac events (MACEs) in patients with atrial fibrillation (AF).

PATIENTS AND METHODS

This study is a single-center prospective observational cohort study including 2366 outpatients with non-valvular AF on treatment with DOACs or vitamin K antagonists (VKAs) from February 2008 for patients on VKA and September 2013 for patients on novel oral anticoagulants. The primary endpoint was the incidence of MACE including fatal and non-fatal myocardial infarction (MI), cardiac revascularization, and cardiovascular death.

RESULTS

The mean age was 75.1±9.0 years; 44.7% were women. During a mean follow-up of 33.3±21.9 months (6567 patients/years) 133 MACEs occurred (2.03%/year): 79 MI/cardiac revascularization and 54 cardiovascular deaths. Of these, 101 were on VKAs (2.42%/year) and 32 on DOACs (1.34%/year; log-rank test P=.040). This difference was evident also considering MI alone (1.53%/year and 0.63%/year in the VKA and DOAC group, respectively, log-rank test P=.009). At multivariable Cox proportional hazard regression analysis, use of DOACs was associated with a lower risk of MACE (hazard ratio, 0.636; 95% CI, 0.417 to 0.970; P=.036) and MI (hazard ratio, 0.497; 95% CI, 0.276 to 0.896; p=.020). Sensitivity analysis showed that this association was consistent in younger patients (<75 years), in patients with anemia, and in those without chronic obstructive pulmonary disease and heart failure. We also found that both dabigatran and apixaban/rivaroxaban were associated with a lower rate of MACE, with similar efficacy between full and low doses.

CONCLUSION

DOACs are associated with a lower risk of MACE in patients with AF independently from dosage.

The Risk of Myocardial Infarction in Patients with Atrial Fibrillation Taking a Direct Thrombin Inhibitor: Myths and Reality

The purpose of this review is to analyze the results of randomized clinical trials, meta-analyses of cohort and observational studies in real clinical practice on the influence of dabigatran etexilate on the risk of myocardial infarction in patients with atrial fibrillation. A pivotal RE-LY study on dabigatran use in patients with atrial fibrillation did not show statistically significant differences in the frequency of myocardial infarction between any of the doses of dabigatran and warfarin, and the risk of coronary events did not depend on the presence of coronary heart disease or myocardial infarction in the patient's history. Subsequently, a number of meta-analyses have reported an increased risk of myocardial infarction when dabigatran was administered to patients with atrial fibrillation. In general, these studies were characterized by conflicting data, which did not allow to draw any definite conclusions regarding the use of dabigatran in relation to the risk of myocardial infarction. Two FDA cohort observational studies were published in 2014 and 2017, and the former was significantly criticized by experts, and the results of the second study did not provide a definitive answer to the question about the importance of the effect of dabigatran on the development of myocardial infarction in patients with atrial fibrillation. Even more "confusing" the problem arose after the publication of meta-analyses of randomized trials, which showed that the risk of myocardial infarction was increased in patients treated with direct oral anticoagulants compared to patients treated with warfarin. This review provides high quality evidence for the efficacy of dabigatran in preventing myocardial infarction and other vascular complications in patients with atrial fibrillation.

Fitting the right non-vitamin K antagonist oral anticoagulant to the right patient with non-valvular atrial fibrillation: an evidence-based choice

Atrial fibrillation (AF) is the most prevalent arrhythmia and is associated with an increased risk of ischemic stroke (IS) and systemic embolism (SE). Stroke prevention is a key element for the overall management of AF patients. The non-vitamin K antagonist oral anticoagulants (NOACs), such as dabigatran, rivaroxaban, apixaban and edoxaban, are at least as effective as warfarin in reducing IS/SE with a lower rate of major bleeding. Various analyses from the large Phase III randomized trials demonstrated different efficacy and safety of NOACs in specific subgroups of patients. The randomized trials are supplemented by effectiveness and safety data from real-world observational cohorts following the availability of these drugs for use in everyday clinical practice. Given the clinical heterogeneity of AF patients, the available data from trials and real-world studies allow us to fit the right NOAC to the particular patient's characteristics, with the aim of optimizing outcomes for the individual patient. This review article aims to provide a summary of the evidence on the performance of NOACs in AF patients with specific clinical characteristics. Evidence-based suggestions are presented to provide a simple and viable strategy for clinicians for the choice of a particular NOAC. KEY MESSAGE Given the different performance of the new-oral anticoagulants in patients with the different clinical situation, evidence-based choice of fitting the right new-oral anticoagulants to the patients is provided in this review article.

Stroke prevention in atrial fibrillation: Past, present and future

Concepts and our approaches to stroke prevention in atrial fibrillation (AF) have changed markedly over the last decade. There has been an evolution over the approach to stroke and bleeding risk assessment, as well as new treatment options. An increasing awareness of AF has led to calls to improve the detection of and population screening for AF. Stroke and bleeding risk assessment continues to evolve, and the ongoing debate on balance between simplicity and practicality, against precision medicine will continue. In this review article, we provide an overview of past, present and the (likely) future concepts and approaches to stroke prevention in AF. We propose three simple steps (the Birmingham ‘3-step’) that offers a practical management pathway to help streamline and simplify decision-making for stroke prevention in patients with AF.

Note: The review process for this paper was fully handled by Christian Weber, Editor in Chief.

Recent advances in the understanding and management of atrial fibrillation: a focus on stroke prevention

Atrial fibrillation (AF) is associated with an increased risk of stroke compared with the general population. It is anticipated that by 2030 an estimated 14-17 million patients will be diagnosed with this most prevalent arrhythmia within the European Union. AF-related stroke confers a higher mortality and morbidity risk, and thus early detection and assessment for the initiation of effective stroke prevention with oral anticoagulation (OAC) is crucial. Recent guidelines point to the use of non-vitamin K antagonist OACs (NOACs) where appropriate in stroke prevention of patients with non-valvular AF. At present, there are four NOACS available, with no direct head-to-head comparisons to suggest the superiority of one drug over another. Simple and practical risk assessment tools have evolved over the years to facilitate stroke and bleeding risk assessment in busy clinics and wards to aid decision-making. At present, the CHA ₂DS ₂VASc (congestive heart failure, hypertension, age 65-74/>75, diabetes mellitus, stroke/transient ischemic attack/thromboembolism, vascular disease, female sex) score is recommended by many international guidelines as a simple and practical method of assessing stroke risk in such patients. Alongside this, use of the HAS BLED (hypertension systolic blood pressure >160 mmHg, abnormal liver/renal function [with creatinine ≥200 μmol/L], stroke, bleeding history or predisposition, labile international normalized ratio [range <60% of the time], elderly [>65], concomitant drugs/alcohol) score aims to identify patients at high risk of bleeding for more regular review and follow-up and draws attention to potentially reversible bleeding risk factors. The aim of this review article is to provide an overview of recent advances in the understanding and management of AF with a focus on stroke prevention.