Age as a Risk Factor for Stroke in Atrial Fibrillation Patients

2012 HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design

This is a report of the Heart Rhythm Society (HRS) Task Force on Catheter and Surgical Ablation of Atrial Fibrillation, developed in partnership with the European Heart Rhythm Association (EHRA), a registered branch of the European Society of Cardiology and the European Cardiac Arrhythmia Society (ECAS), and in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), the Asia Pacific Heart Rhythm Society (APHRS), and the Society of Thoracic Surgeons (STS). This is endorsed by the governing bodies of the ACC Foundation, the AHA, the ECAS, the EHRA, the STS, the APHRS, and the HRS.

Hypertension and atrial fibrillation: diagnostic approach, prevention and treatment. Position paper of the Working Group 'Hypertension Arrhythmias and Thrombosis' of the European Society of Hypertension

Hypertension is the most common cardiovascular disorder and atrial fibrillation is the most common clinically significant arrhythmia. Both these conditions frequently coexist and their prevalence increases rapidly with aging. There are different risk factors and clinical conditions predisposing to the development of atrial fibrillation, but due its high prevalence, hypertension is still the main risk factor for the development of atrial fibrillation. Several pathophysiologic mechanisms (such as structural changes, neurohormonal activation, fibrosis, atherosclerosis, etc.) have been advocated to explain the onset of atrial fibrillation. The presence of atrial fibrillation per se increases the risk of stroke but its coexistence with high blood pressure leads to an abrupt increase of cardiovascular complications. Different risk models are available for the risk stratification and the prevention of thromboembolism in patients with atrial fibrillation. In all of them hypertension is present and is an important risk factor. Antihypertensive treatment may contribute to reduce this risk, and it seems some classes are superior to others in the prevention of new-onset atrial fibrillation and prevention of stroke. Antithrombotic treatment with warfarin is effective in the prevention of thromboembolic events, although quite recently, new classes of anticoagulants that do not require international normalized ratio monitoring have been introduced with promising results.

Atrial electromechanical coupling interval and P-wave dispersion in patients with white coat hypertension

BACKGROUND

The aim of our study was to investigate the effect of white coat hypertension (WCH) to atrial conduction abnormalities by electrocardiographic P-wave analysis and echocardiographic electromechanical coupling (EMC) interval measurement.

METHODS

The study consisted of sex-, age-, and body mass index-matched 24 patients with WCH, 24 patients with sustained hypertension (SH), and 24 subjects with normotension (NT). The difference between the maximum (Pmax) and minimum P-wave durations on 12-lead electrocardiography was defined as P-wave dispersion (PD). Intra- and inter-atrial EMC were measured by tissue Doppler imaging.

RESULTS

Pmax and PD of subjects with WCH were significantly higher than those of normotensives and lower than those of patients with SH. Inter-atrial EMC and left atrial EMC values of WCH group were intermediate between NT and SH groups. There was a significant correlation between left atrial diameter, PD, Pmax, left ventricle mass index, left atrial EMC, and inter-atrial EMC.

CONCLUSION

White coat hypertension is an intermediate group between SH and NT in terms of atrial electromechanical abnormalities which may be associated with the risk of atrial fibrillation.

Comprehensive risk reduction in patients with atrial fibrillation: emerging diagnostic and therapeutic options--a report from the 3rd Atrial Fibrillation Competence NETwork/European Heart Rhythm Association consensus conference

While management of atrial fibrillation (AF) patients is improved by guideline-conform application of anticoagulant therapy, rate control, rhythm control, and therapy of accompanying heart disease, the morbidity and mortality associated with AF remain unacceptably high. This paper describes the proceedings of the 3rd Atrial Fibrillation NETwork (AFNET)/European Heart Rhythm Association (EHRA) consensus conference that convened over 60 scientists and representatives from industry to jointly discuss emerging therapeutic and diagnostic improvements to achieve better management of AF patients. The paper covers four chapters: (i) risk factors and risk markers for AF; (ii) pathophysiological classification of AF; (iii) relevance of monitored AF duration for AF-related outcomes; and (iv) perspectives and needs for implementing better antithrombotic therapy. Relevant published literature for each section is covered, and suggestions for the improvement of management in each area are put forward. Combined, the propositions formulate a perspective to implement comprehensive management in AF.

Stroke prevention in elderly patients with atrial fibrillation: challenges for anticoagulation

Elderly patients with atrial fibrillation (AF), who constitute almost half of all AF patients, are at increased risk of stroke. Anticoagulant therapies, especially vitamin K antagonists (VKA), reduce the risk of stroke in all patients including the elderly but are frequently under-used in older patients. Failure to initiate VKA in elderly AF patients is related to a number of factors, including the limitations of current therapies and the increased risk for major haemorrhage associated with advanced age and anticoagulation therapy. Of particular concern is the risk of intracranial haemorrhages (ICH), which is associated with high rates of mortality and morbidity. Novel oral anticoagulant agents that are easier to use and might offer similar or better levels of stroke prevention with a similar or reduced risk of bleeding should increase the use of antithrombotic therapy in the management of elderly AF patients. Amongst these new agents, the recently approved direct thrombin inhibitor dabigatran provides effective stroke prevention with a significant reduction of ICH, and enables clinicians to tailor the dose according to age and haemorrhagic risk.

Management of patients with atrial fibrillation: specific considerations for the old age

Atrial fibrillation (AF) is the commonest of all sustained arrhythmias, and most of the patients seeking medical therapy are in the elderly age group. The management of these patients is particularly difficult due to associated comorbidities. Hypertension, congestive heart failure, left ventricular hypertrophy, and coronary artery disease are often present in the elderly patient population, and therefore, antiarrhythmic drugs often fail due to side effects, proarrhythmia, or poor rhythm control. Recently, radiofrequency catheter ablation has been widely performed as an efficient therapy for recurrent, drug-refractory AF. Nevertheless, patients at old age were underrepresented in prior AF ablation trials, and the current guidelines for catheter ablation of AF recommend a noninvasive approach in the elderly patient group due to the lack of clinical data supporting ablation therapy. However, study results of our group and others are suggesting that catheter ablation is a safe and effective treatment for patients over the age of 65 years with symptomatic, drug-refractory AF, and therefore, patients should not be precluded from catheter ablation only on the basis of age. This paper discusses the pharmacological (rhythm control, rate control, and anticoagulation) and catheter management of AF in the elderly population.

Bleeding risk in 'real world' patients with atrial fibrillation: comparison of two established bleeding prediction schemes in a nationwide cohort

BACKGROUND

Oral anticoagulation (OAC) in patients with atrial fibrillation (AF) is a double-edged sword, because it decreases the risk of stroke at the cost of an increased risk of bleeding. We compared the performance of a new bleeding prediction scheme, HAS-BLED, with an older bleeding prediction scheme, HEMORR(2)HAGES, in a cohort of 'real-world' AF patients.

METHODS

By individual-level-linkage of nationwide registers, we identified all patients (n = 118,584) discharged with non-valvular AF in Denmark during the period 1997-2006, with and without OAC. Major bleeding rates during 1 year of follow-up were determined, and the predictive capabilities of the two schemes were compared by c-statistics. The risk of bleeding associated with individual risk factors composing HAS-BLED was estimated using Cox proportional-hazard analyses.

RESULTS

Of AF patients receiving OAC (n = 44,771), 34.8% and 47.3% were categorized as 'low bleeding risk' by HAS-BLED and HEMORR(2)HAGES, respectively, and the bleeding rates per 100 person-years were 2.66 (95% confidence interval [CI], 2.40-2.94) and 3.06 (2.83-3.32), respectively. C-statistics for the two schemes were 0.795 (0.759-0.829) and 0.771 (0.733-0.806), respectively. The risk factors composing HAS-BLED were associated with varying risks, with a history of bleeding (hazard ratio [HR] 2.98; 95% CI 2.68-3.31) and being elderly (HR 1.93; 95% CI 1.71-2.18) being associated with the highest risks. Comparable results were found in AF patients not receiving OAC (n = 77,813).

CONCLUSIONS

In an unselected nationwide cohort of hospitalized patients with atrial fibrillation, the HAS-BLED score performs similarly to HEMORR(2)HAGES in predicting bleeding risk but HAS-BLED is much simpler and easier to use in everyday clinical practise.

Cardiovascular disease in the elderly

The aging of the population worldwide will result in increasing numbers of elderly patients, among whom heart disease is the leading cause of death. Changes in cardiovascular physiology with normal aging and prevalent comorbidities result in differences in the effects of common cardiac problems as well as the response to their treatments. Patient-centered goals of care such as maintenance of independence and reduction of symptoms may be preferred over increased longevity. New less-invasive treatments are likely to improve outcomes in elderly patients who previously have been considered at prohibitive risk for traditional procedures. Clinical trials enrolling elderly patients are limited and recommendations for management from younger patients frequently lack evidence-based support in patients aged >75 years.

Atrial fibrillation in the aging heart: pharmacological therapy and catheter ablation in the elderly

The majority of patients with atrial fibrillation (AF) seeking medical treatment are in the elderly age group and the management of these patients is often complicated by comorbidities, challenging the pharmacological management of these patients. Owing to hypertension, congestive heart failure, left ventricular hypertrophy and coronary artery disease, antiarrhythmic treatment often fails due to side effects, proarrhythmia or poor rhythm control. In recent years, radiofrequency catheter ablation has been widely performed as an effective treatment for recurrent, drug-refractory AF. However, few elderly patients were included in prior AF catheter ablation studies and the current guidelines for catheter ablation of AF recommend a conservative approach in the elderly population owing to the absence of clinical data. However, study results from our group and others suggest that catheter ablation is a safe and effective treatment for patients over the age of 65 years with symptomatic, drug-refractory AF and, therefore, patients should not be excluded from catheter ablation on the basis of age alone. In this article, we discuss the pharmacological (rhythm control, rate control and anticoagulation) and catheter management of AF in the elderly population.

A review of the safety of anticoagulants in older people using the medicines management pathway: weighing the benefits against the risks

Anticoagulant drugs maintain a high potential for adverse events due to their inherent risk of haemorrhage and/or complex pharmacology. In addition, compromising the safety of these agents is the context in which they are principally used; that is, in the long-term prevention of thromboembolic diseases in an older patient population. These challenges are especially pronounced in the prevention of stroke in older persons with atrial fibrillation (AF), where the need for thromboprophylaxis is paramount and in whom the arrhythmia is most prevalent, but where the target population is simultaneously at high risk of adverse drug events. Essentially, this translates to the use of high-risk therapies on an indefinite basis, in persons who have multiple comorbidities, use polypharmacy, and who may have age-related functional and cognitive decline, culminating in a higher potential for medication misadventure. For this reason, anticoagulants mandate extra pharmacovigilance, and therefore the aim of this review is to address some of the key safety considerations in the use of anticoagulant drugs (warfarin, dabigatran, rivaroxaban), spanning the initiation of therapy to its ongoing management. Using the Medication Management Pathway (MMP) as a framework, in this review we canvas and highlight specific developments in practical strategies to facilitate the safe use of anticoagulants (particularly warfarin) in 'at-risk' elderly patients including: comprehensive risk/benefit assessment using novel risk stratification tools; focused medicines review services; therapeutic drug monitoring services delivered in the primary care setting; and practical education strategies and resources targeting the older patient population. Until newer alternative anticoagulants become viable options for widespread use, clinicians will necessarily need to rely on specific resources and interventions to facilitate the safe use of currently available anticoagulants (i.e. warfarin) in 'at-risk' older people.

[Update on geriatric cardiology]

This article contains a review of the main developments in the field of geriatric cardiology reported during 2010. The focus is on research into the specific characteristics of elderly patients with heart failure, ischemic heart disease, valvular heart disease and arrhythmias.

Validation of risk stratification schemes for predicting stroke and thromboembolism in patients with atrial fibrillation: nationwide cohort study

OBJECTIVES

To evaluate the individual risk factors composing the CHADS(2) (Congestive heart failure, Hypertension, Age ≥ 75 years, Diabetes, previous Stroke) score and the CHA(2)DS(2)-VASc (CHA(2)DS(2)-Vascular disease, Age 65-74 years, Sex category) score and to calculate the capability of the schemes to predict thromboembolism.

DESIGN

Registry based cohort study.

SETTING

Nationwide data on patients admitted to hospital with atrial fibrillation. Population All patients with atrial fibrillation not treated with vitamin K antagonists in Denmark in the period 1997-2006.

MAIN OUTCOME MEASURES

Stroke and thromboembolism.

RESULTS

Of 121,280 patients with non-valvular atrial fibrillation, 73,538 (60.6%) fulfilled the study inclusion criteria. In patients at "low risk" (score = 0), the rate of thromboembolism per 100 person years was 1.67 (95% confidence interval 1.47 to 1.89) with CHADS(2) and 0.78 (0.58 to 1.04) with CHA(2)DS(2)-VASc at one year's follow-up. In patients at "intermediate risk" (score = 1), this rate was 4.75 (4.45 to 5.07) with CHADS(2) and 2.01 (1.70 to 2.36) with CHA(2)DS(2)-VASc. The rate of thromboembolism depended on the individual risk factors composing the scores, and both schemes underestimated the risk associated with previous thromboembolic events. When patients were categorised into low, intermediate, and high risk groups, C statistics at 10 years' follow-up were 0.812 (0.796 to 0.827) with CHADS(2) and 0.888 (0.875 to 0.900) with CHA(2)DS(2)-VASc.

CONCLUSIONS

The risk associated with a specific risk stratification score depended on the risk factors composing the score. CHA(2)DS(2)-VASc performed better than CHADS(2) in predicting patients at high risk, and those categorised as low risk by CHA(2)DS(2)-VASc were truly at low risk for thromboembolism.