Atrial fibrillation in the older adult. Presentation and management issues

Atrial fibrillation (AF) is a common cardiac arrhythmia in older adults and the most common cause of embolic stroke. Diagnosis of this illness is a challenge in that the older adult may be asymptomatic and/or may present with such atypical symptoms as a change in function, mood, or cognition. This challenge is demonstrated in three vignettes of older individuals who presented with acute onset AF. Nurses need to evaluate older patients for AF so that prompt treatment can be initiated. This proactive approach can have a major impact on preventing strokes and improving the quality of life in these individuals.     

Stroke prevention in atrial fibrillation: current anticoagulation management and future directions

Atrial fibrillation (AF) is an important cause of stroke, and stroke risk stratification is critical to the management of patients with AF. Anticoagulation with warfarin is the current standard of care for stroke prevention in these patients, despite the need for close monitoring. Aspirin alone is not as effective. Warfarin is recommended for patients with AF and valvular disease or with AF and one or more stroke risk factors. Other novel anticoagulants and antiplatelet combinations are under investigation. Curative procedures for AF are possible, but their long-term safety and effect on stroke risk are unknown.     

AF burden is important – fact or fiction?

Asymptomatic atrial fibrillation (AF) is common and in view of its prognostic impact (the same as of clinically overt AF) knowledge of the overall AF burden (defined as the amount of time spent in AF) appears to be important, both for scientific and clinical reasons. Data collected on more than 12,000 patients indicate that cardiac implantable electrical devices (CIEDs) are validated tools for measuring AF burden and that AF burden is associated with an increased risk of stroke. A maximum daily AF burden of ≥ 1 h carries important negative prognostic implications and may be a clinically relevant parameter for improving risk stratification for stroke. Decision‐making should primarily consider the context in which asymptomatic, subclinical arrhythmias are detected (i.e. primary or secondary prevention of stroke and systemic embolism) and the risk profile of every individual patient with regard to thromboembolic and haemorrhagic risk, as well as patient preferences and values. Continuous monitoring using CIEDs with extensive data storage capabilities allow in‐depth study of the temporal relationship between AF and ischaemic stroke. The relationships between AF and stroke are complex. AF is certainly a risk factor for cardioembolic stroke, with a cause–effect relationship between the arrhythmia and a thromboembolic event, the latter being related to atrial thrombi. However, AF can also be a simple ‘marker of risk’, with a non‐causal association between the arrhythmia and stroke, the latter being possibly related to atheroemboli from the aorta, the carotid arteries or from other sources.     

Pharmacologic and nonpharmacologic therapies for stroke prevention in nonvalvular atrial fibrillation

Thromboembolism is the crucial cause of ischemic stroke in patients with atrial fibrillation (AF). Anticoagulation therapy with vitamin K antagonists, such as warfarin, have been proven to be effective for stroke prevention in AF. Nonetheless, the use of warfarin may be limited due to increased risk of bleeding, the potential interaction with multiple foods and drugs, and the need for routine coagulation monitoring. Over the last decade anticoagulants, such as dabigatran and rivaroxaban, have been developed and have shown superiority compared to warfarin for preventing stroke in patients with nonvalvular AF in large randomized trials. In addition, on account of the risk of thrombus formation in the left atrial appendage (LAA), many nonpharmacologic approaches have been developed to reduce stroke risk in patients with AF who are not candidates for anticoagulant therapy. Surgical, epicardial, and endovascular techniques for LAA closure are being investigated currently. Both novel pharmacotherapy and nonpharmacologic approaches for stroke prevention will be detailed in this review.     

Management of the adverse effects of lenalidomide in multiple myeloma

Atrial fibrillation (AF) is becoming increasingly common in an ageing population. Much of the morbidity and mortality in AF is due to stroke and thromboembolism. Awareness of stroke risk and the need for prevention is well recognized but is far from satisfactory in the real world. Despite refinements in the risk stratification over the years, there is an unmet need for appropriate thromboprophylaxis due to the underuse of oral anticoagulation. Primary care physicians and generalists bear the burden of managing AF. Coordinated multidisciplinary efforts by cardiologists, primary care physicians, and neurologists may be needed to meet the increasing challenge of stroke prevention and rhythm management in AF. This article discusses the potential the role of the cardiologist in the management of stroke prevention in patients with AF.     

Novel antithrombotic agents for atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia. It is estimated that 1 in 4 individuals aged 40 years or above will develop at least 1 episode of AF during their lifetime. Stroke is a leading cause of serious, long-term disability and death, and a major socioeconomic burden in developed countries. The major risk factor for thromboembolic stroke is AF. Oral antithrombotic treatment for AF patients has been limited to vitamin K antagonists for more than 60 years. Treatment with warfarin can reduce, but fails to abolish thromboembolic stroke associated with AF. Despite anticoagulation, patients with AF are at increased stroke risk. Furthermore, warfarin has important limitations namely, the limited time in therapeutic range, the need for INR monitoring, risk of major bleeding including stroke, and drug interactions. Recently there have been very exciting and important new advances in thromboprophylaxis for AF. Novel oral agents have been developed and evaluated clinically. These include direct thrombin inhibitors (dabigatran etexilate), oral selective factor Xa inhibitors (rivaroxaban, apixaban and edoxaban) and PAR-1 inhibitors (vorapaxar and atopaxar). Some of the new drugs have demonstrated promising results in the clinical studies, they are convenient in use and do not require monitoring. The downsides are lack of antidotes or specific blood assays to monitor the anticoagulant effect. This review evaluates traditional and novel approaches to thromboprophylaxis in patients with AF.     

A comparison of risk stratification schemes for stroke in 79 884 atrial fibrillation patients in general practice

Summary. Background: Anticoagulation management of patients with atrial fibrillation (AF) should be tailored individually on the basis of ischemic stroke risk. The objective of this study was to compare the predictive ability of 15 published stratification schemes for stroke risk in actual clinical practice in the UK. Methods: AF patients aged ≥ 18 years in the General Practice Research Database, which contains computerized medical records, were included. The c‐statistic was estimated to determine the predictive ability for stroke for each scheme. Outcomes included stroke, hospitalizations for stroke, and death resulting from stroke (as recorded on death certificates). Results: The study cohort included 79 844 AF patients followed for an average of 4 years (average of 2.4 years up to the start of warfarin therapy). All risk schemes had modest discriminatory ability in AF patients, with c‐statistics for predicting events ranging from 0.55 to 0.69 for strokes recorded by the general practitioner or in hospital, from 0.56 to 0.69 for stroke hospitalizations, and from 0.56 to 0.78 for death resulting from stroke as reported on death certificates. The proportion of patients assigned to individual risk categories varied widely across the schemes, with the proportion categorized as moderate risk ranging from 12.7% (CHA₂DS₂‐VASc) to 61.5% (modified CHADS₂). Low‐risk subjects were truly low risk (with annual stroke events < 0.5%) with the modified CHADS₂, National Institute for Health and Clinical Excellence and CHA₂DS₂‐VASc schemes. Conclusion: Current published risk schemes have modest predictive value for stroke. A new scheme (CHA₂DS₂‐VASc) may discriminate those at truly low risk and minimize classification of subjects as intermediate/moderate risk. This approach would simplify our approach to stroke risk stratification and improve decision‐making for thromboprophylaxis in patients with AF.     

Incidental atrial fibrillation and its management

Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia, yet because AF can often be intermittent or lacking in overt symptoms, its prevalence is underestimated, and it may be diagnosed only incidentally. Because AF is a potent ischemic stroke risk factor and stroke rates are similar for paroxysmal, persistent, and permanent AF, all AF types require prompt management. This involves identifying and treating underlying causative factors, then implementing a "rate-control" or "rhythm-control" strategy. Regardless of approach, concomitant antithrombotic therapy for stroke risk reduction is recommended. Antithrombotic agent choice (acetylsalicylic acid or warfarin) depends on level of stroke risk; this review covers both the CHADS2 and CHA2DS2-VASc risk stratification schemes. Warfarin provides effective ischemic stroke prophylaxis but has numerous drawbacks, including a narrow therapeutic range, unpredictable pharmacokinetics, slow on-/offset of action, and multiple food and drug interactions. New oral anticoagulants that lack many of these drawbacks are in development. Here we review these drugs for stroke prevention in AF.     

Antithrombotic therapy for stroke prevention in patients with atrial fibrillation

Atrial fibrillation(AF) is a common arrhythmia that is an important independent risk factor for stroke. The overall risk of stroke in AF patients averages about 5%/y, but with wide variation depending on the presence of coexistent thromboembolic risk factors, which include increasing age, history of hypertension, previous stroke or transient ischemic attack(TIA), and diabetes. AF patients with prior stroke or TIA are at highest risk(about 12%/y). Adjusted-dose warfarin(target INR 2.0-3.0) is highly efficacious for preventing stroke in AF patients, and is safe for selected patients. Aspirin has a modest effect on reducing stroke. Warfarin is recommended for high-risk AF patients who can safely receive it. Aspirin may be indicated for those with a low stroke risk and for those who cannot receive warfarin.     

Update on anti-coagulation in atrial fibrillation

Atrial fibrillation (AF), the most common clinically relevant arrhythmia, affects 2.2 million individuals in the USA and 4.5 million in Europe, resulting in significant morbidity and mortality. Pharmacotherapy aimed at controlling both heart rate and rhythm is employed to relieve AF symptoms, though debate continues about which approach is preferable. AF prevalence rises with age from 0.4% to 1% in the general population to 11% in those aged >70 years. AF is associated with a pro-thrombotic state and other comorbidities; age, hypertension, heart failure and diabetes mellitus all play a key role in AF pathogenesis. Anti-coagulation is essential for stroke prevention in patients with AF and is recommended for patients with one or more risk factors for stroke. Used within the recommended therapeutic range, warfarin and other vitamin K antagonists decrease the incidence of stroke and mortality in AF patients. Warfarin remains under-used, however, because of the perceived high risk of haemorrhage, narrow therapeutic window and need for regular monitoring. Several novel anti-coagulants show promise in AF-related stroke prevention. In particular, the novel, oral, direct thrombin inhibitor, dabigatran etexilate, recently licensed by the US Food and Drug Administration (FDA) and Health Canada has shown improved efficacy and safety compared with warfarin for stroke prevention in AF, and has the potential to replace warfarin in this indication. The increasing number of new therapeutic options, including improved anti-arrhythmic agents, novel anti-coagulants and more accessible ablation techniques, are likely to deliver better care for AF patients in the near future.     

Aspirin in stroke prevention in nonvalvular atrial fibrillation and stable vascular disease: an era of new anticoagulants

Atrial fibrillation (AF) is a major cause of ischemic stroke, especially in the elderly. There are currently enough data to support the notion that anticoagulation with warfarin or dabigatran is far superior to aspirin in the prevention of stroke or systemic embolism in AF. Aspirin is the preferred modality in patients who are either not candidates for anticoagulation, such as patients with increased risk for bleeding, low-risk patients based on the CHADS2 score or patients who have difficulty in maintaining a therapeutic international normalized ratio. There is no dispute on the recommendations regarding stroke prevention in high-risk patients (CHADS2 risk score of 2 and beyond) with AF. However, there is some controversy regarding the appropriate strategy (anticoagulation vs aspirin) for stroke prevention in low-risk patients (CHA2DS2-VASc score of 0-1). Novel oral anticoagulant drugs (direct thrombin inhibitors and Factor Xa inhibitors) might further diminish the role of aspirin for stroke prevention in AF due to their superior efficacy, lack of need for monitoring of therapeutic effects and lower bleeding risk when compared with warfarin, especially in patients with stable vascular disease.     

老年患者房颤并发脑卒中的临床特征及其预后

为探讨老年患者房颤并发脑卒中的临床特征和预后，将房颤并发首次脑卒中的２５例老年患者列为研究对象（ＡＦ组），另选年龄、性别与ＡＦ组相匹配的脑血栓形成脑卒中患者２５例为对照组，分别于脑卒中发病〉４８ｈ和治疗１个后评估２组患者的神经功能缺损程度和日常生活活动功能（ＡＤＬ）。结果：入院时ＡＦ组的神经功能和ＡＤＬ与对照组比较差异有显著性（Ｐ〈０．０５和０．００１）；１个月的ＡＦ神经功能和ＡＤＬ的恢复程度仍明     

Antithrombotics in atrial fibrillation and coronary disease

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia and approximately 18–45% of AF patients have concomitant coronary artery disease (CAD). Several studies have demonstrated that oral anticoagulation is the mainstay of therapy for stroke prevention in AF. Similarly, antiplatelet therapy including aspirin and P2Y12 inhibitor is recommended in the management of acute coronary syndrome and stable CAD. Despite the high prevalence of CAD with AF, practice guidelines are scarce on the appropriate antithrombotic regimen due to lack of large-scale randomized clinical trials. The use of direct thrombin and factor Xa inhibitors for stroke prevention in AF has also complicated the possible combinations of antithrombotic therapies. This review aims to discuss the available evidence regarding aspirin as an antithrombotic strategy, the role of novel anticoagulants and the specific clinical situations where aspirin may be beneficial in patients with AF and CAD.     

The impact of comorbidities on stroke prophylaxis strategies in atrial fibrillation patients

Arial fibrillation (AF) is the most commonly occurring sustained arrhythmia in the United States and is associated with increased mortality. AF is a risk factor for ischemic stroke, and risk factors for AF include comorbid conditions such as congestive heart failure, diabetes mellitus, older age, hypertension, diabetes, pulmonary disease, and history of stroke, transient ischemic attack, or heart failure. Risk stratification for ischemic stroke in AF patients is based on scoring a group of risk factors that allows for the appropriate tailoring of antithrombotic therapy. The vitamin K antagonists are effective at reducing ischemic stroke rates in medium-risk to high-risk patients and are therefore generally recommended for this group. However, a large proportion of these patients are not treated with vitamin K antagonists because of the potential for adverse outcomes, particularly in elderly patients. New direct thrombin inhibitors and direct Factor Xa inhibitors in development offer the possibility of simplifying treatment and management although offering similar or better efficacy and safety profiles to warfarin. In light of these potential new treatments, the importance and improvement of risk stratification methods and the resulting recommendations in thromboprophylaxis become even more paramount as they make it more likely that medium-risk to high-risk patients can be treated safely.     

Combination of clopidogrel and aspirin for reduction of vascular events in patients with atrial fibrillation

Evaluation of: The ACTIVE Investigators. Effect of clopidogrel added to aspirin in patients with atrial fibrillation. N. Engl. J. Med. 360(20), 2066–2078 (2009).

Atrial fibrillation (AF) is the most common heart rhythm disorder and increases the risk for stroke by fivefold. Therefore, antithrombotic pharmacological agents are recommended and commonly used to prevent stroke and thromboembolic vascular events in patients with AF. Although, aspirin is an effective and acceptable agent for low-risk patients, oral vitamin K antagonists anticoagulants have superiority over aspirin in patients with AF who are at high risk for complications. However, given several practical impediments, vitamin K antagonists may not be suitable for certain high-risk patients with AF. It is not unusual for clinicians to encounter situations where selection of appropriate pharmacotherapy options for stroke prevention may be quite challenging in high-risk patients with AF who are deemed to be unsuitable candidates for oral anticoagulants. It may be hypothesized that, in such a situation, a combination of clopidogrel with aspirin, possibly by their additive effect in the prevention of platelet-mediated thrombosis may be used effectively instead of oral anticoagulants. In this article, we have discussed this issue and review one of the recently published Atrial Fibrillation Clopidogrel Trial with Irbesartan for Prevention of Vascular Events (ACTIVE) studies, the ACTIVE-A trial, in which the treatment strategies utilizing ‘clopidogrel plus aspirin’ and ‘aspirin alone’ in patients with AF who were at increased risk for stroke and for whom therapy with a vitamin K antagonist was considered unsuitable were compared.     

The increasing need for anticoagulant therapy to prevent stroke in patients with atrial fibrillation

Ischemic stroke, a major complication of atrial fibrillation (AF), is believed to result from atrial thrombus formation caused by ineffective atrial contraction. Oral anticoagulant therapy effectively reduces the risk of ischemic stroke in patients with AF; this therapy is recommended for patients with any frequency or duration of AF and other risk factors for stroke, such as increased age (>75 years), hypertension, prior stroke, left ventricular dysfunction, diabetes, or heart failure. Recently published data comparing rate-control and rhythm-control strategies in AF emphasized the importance of maintaining an international normalized ratio higher than 2.0 during warfarin therapy and the need for continuing anticoagulant therapy to prevent stroke in high-risk patients, even if the strategy is rhythm control. Hemorrhagic complications can be minimized by stringent control of the international normalized ratio (particularly in elderly patients) and appropriate therapy for comorbidities such as hypertension, gastric ulcer, and early-stage cancers. Undertreatment of patients with AF is a continuing problem, particularly in the elderly population. Patients perceived as likely to be noncompliant, such as the functionally impaired, are less likely to receive warfarin therapy. However, stroke prevention with anticoagulants is cost-effective and improves quality of life, despite the challenges of maintaining appropriate anticoagulation with monitoring and warfarin dose titration. New medications in development with more predictable dosing and fewer drug-drug interactions may reduce the complexities of achieving optimal anticoagulation and increase the practicality of long-term anticoagulant therapy for patients with AF at risk of stroke.     

Decision-Making in Clinical Practice: Oral Anticoagulant Therapy in Patients with Non-valvular Atrial Fibrillation and a Single Additional Stroke Risk Factor

Approximately 1 in 3–4 patients presenting with an ischemic stroke will also have atrial fibrillation (AF), and AF-related strokes can be effectively prevented using oral anticoagulant therapy (OAC), either with well-controlled vitamin K antagonists (VKAs) or non-vitamin K antagonist oral anticoagulants (NOACs). In addition, OAC use (both VKAs and NOACs) is associated with a 26% reduction in all-cause mortality (VKAs) or an additional 10% mortality reduction with NOACs relative to VKAs. The decision to use OAC in individual AF patient is based on the estimated balance of the benefit from ischemic stroke reduction against the risk of major OAC-related bleeding [essentially intracranial hemorrhage (ICH)]. Better appreciation of the importance of VKAs’ anticoagulation quality [a target time in therapeutic range (TTR) of ≥70%] and the availability of NOACs (which offer better safety compared to VKAs) have decreased the estimated threshold for OAC treatment in AF patients towards lower stroke risk levels. Still, contemporary registry-based data show that OAC is often underused in AF patients at increased risk of stroke. The uncertainty whether to use OAC may be particularly pronounced in AF patients with a single additional stroke risk factor, who are often (mis)perceived as having a “borderline” or insufficient stroke risk to trigger the use of OAC. However, observational data from real-world AF cohorts show that the annual stroke rates in such patients are higher than in patients with no additional stroke risk factors, and OAC use has been associated with reduction in stroke, systemic embolism, or death in comparison to no therapy or aspirin, with no increase in the risk of bleeding relative to aspirin. In this review article, we summarize the basic principles of stroke risk stratification in AF patients and discuss contemporary real-world evidence on OAC use and outcomes of OAC treatment in AF patients with a single additional stroke risk factor in various real-world AF cohorts.     

Left atrial appendage occlusion for stroke prevention in patients with atrial fibrillation

The most severe consequence of atrial fibrillation (AF) is a cardioembolic stroke. The incidence of cardioembolic stroke increases significantly in patients with AF. Although warfarin has been the mainstay of the prevention of cardioembolic stroke, there are several limitations to the use of warfarin that hinder its effectiveness. This article provides the historical development of devices that exclude the left atrial appendage, their effectiveness and potential patient selection, as an alternative to warfarin and the novel oral anticoagulation therapy for the prevention of cardioembolic stroke in patients with AF.     

Prevention of cardioembolic stroke in patients with atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia and an important independent stroke risk factor, especially in the elderly. This article provides the reader with an overview as well as an update on primary and secondary stroke prevention strategies in patients with AF. Vitamin K antagonists remain the cornerstone therapy in AF patients at high risk of stroke. Both aspirin monotherapy and the combination of aspirin and clopidogrel are inferior to vitamin K antagonists in patients with AF. The new direct thrombin inhibitor dabigatran is at least as effective as warfarin and leads to a significant and clinically relevant decrease in hemorrhagic stroke and intracranial bleeds. Interventional therapies such as percutaneous closure of the left atrial appendage or radiofrequency catheter ablation have not yet been proven to decrease the stroke risk in patients with AF.     

Prevention of cardioembolic stroke in patients with atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia and an important independent stroke risk factor, especially in the elderly. This article provides the reader with an overview as well as an update on primary and secondary stroke prevention strategies in patients with AF. Vitamin K antagonists remain the cornerstone therapy in AF patients at high risk of stroke. Both aspirin monotherapy and the combination of aspirin and clopidogrel are inferior to vitamin K antagonists in patients with AF. The new direct thrombin inhibitor dabigatran is at least as effective as warfarin and leads to a significant and clinically relevant decrease in hemorrhagic stroke and intracranial bleeds. Interventional therapies such as percutaneous closure of the left atrial appendage or radiofrequency catheter ablation have not yet been proven to decrease the stroke risk in patients with AF.