Warfarin doses for anticoagulation therapy in elderly patients with chronic atrial fibrillation

OBJECTIVE: Anticoagulation is a challenge for the prophylaxis of thromboembolic events in elderly patients with chronic atrial fibrillation. Stable anticoagulation is defined as the time within > 70% of the therapeutic range. However, the dosage required to achieve stable anticoagulation remains unknown. The aim of this study was to analyze the warfarin dose necessary for the maintenance of stable oral anticoagulation therapy in elderly patients. METHODS: We analyzed 112 consecutive outpatients with atrial fibrillation who were >= 65 years of age, had received anticoagulation therapy with warfarin for more than 1 year and had a stable international normalized ratio between 2.0 and 3.0 for >= 6 months. The international normalized ratio was measured in the central laboratory using the traditional method. RESULTS: The patients were stratified according to the following age groups:,75 or >= 75 years and <80 or >= 80 years. The mean daily doses of warfarin were similar for patients, <75 or >= 75 years (3.34 +/- 1.71 versus 3.26 +/- 1.27 mg/day, p = 0.794) and <80 or >= 80 years (3.36 +/- 1.49 versus 3.15 +/- 1.23 mg/day, p = 0.433). In 88 (79%) patients, the daily warfarin dose was between 2 and 5 mg/day; in 13 (11%) patients, the daily warfarin dose was,2.0 mg/day; and in 11 (10%) patients, the daily warfarin dose was >5.0 mg/day. The correlation between the daily warfarin dose and the international normalized ratio was 0.22 (p = 0.012). CONCLUSION: Stable anticoagulation was achieved in 80% of patients who received doses of 2 to 5 mg/day of warfarin, and the mean daily dose was similar across the age groups analyzed.

Predictors of the risk of falls among elderly with chronic atrial fibrillation

OBJECTIVES: Though elderly persons with chronic atrial fibrillation have more comorbidities that could limit indications for the chronic use of anticoagulants, few studies have focused on the risk of falls within this particular group. To evaluate the predictors of the risk of falls among elderly with chronic atrial fibrillation, a cross-sectional, observational study was performed. METHODS: From 295 consecutive patients aged 60 years or older with a history of atrial fibrillation who were enrolled within the last 2 years in the cardiogeriatrics outpatient clinic of the Instituto do Coracao do Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, 107 took part in this study. Their age was 77.9 +/- 6.4 years, and 62 were female. They were divided into two groups: a) no history of falls in the previous year and b) a history of one or more falls in the previous year. Data regarding the history of falls and social, demographic, anthropometric, and clinical information were collected. Multidimensional assessment instruments and questionnaires were applied. RESULTS: At least one fall was reported in 55 patients (51.4%). Among them, 27 (49.1%) presented recurrent falls, with body lesions in 90.4% and fractures in 9.1% of the cases. Multivariate logistic regression showed that self-reported difficulty maintaining balance, use of amiodarone, and diabetes were independent variables associated with the risk of falls, with a sensitivity of 92.9% and a specificity of 44.9%. CONCLUSION: In a group of elderly patients with chronic atrial fibrillation who were relatively independent and able to attend an outpatient clinic, the occurrence of falls with recurrence and clinical consequences was high. Difficulty maintaining balance, the use of amiodarone and a diagnosis of diabetes mellitus were independent predictors of the risk for falls. Thus, simple clinical data predicted falls better than objective functional tests.

Meta-analysis of the influence of chronic kidney disease on the risk of thromboembolism among patients with nonvalvular atrial fibrillation

Chronic kidney disease (CKD) and atrial fibrillation (AF) frequently coexist. However, the extent to which CKD increases the risk of thromboembolism in patients with nonvalvular AF and the benefits of anticoagulation in this group remain unclear. We addressed the role of CKD in the prediction of thromboembolic events and the impact of anticoagulation using a meta-analysis method. Data sources included MEDLINE, EMBASE, and Cochrane (from inception to January 2014). Three independent reviewers selected studies. Descriptive and quantitative information was extracted from each selected study and a random-effects meta-analysis was performed. After screening 962 search results, 19 studies were considered eligible. Among patients with AF, the presence of CKD resulted in an increased risk of thromboembolism (hazard ratio [HR] 1.46, 95% confidence interval [CI] 1.20 to 1.76, p = 0.0001), particularly in case of end-stage CKD (HR 1.83, 95% CI 1.56 to 2.14, p <0.00001). Warfarin decreased the incidence of thromboembolic events in patients with non-end-stage CKD (HR 0.39, 95% CI 0.18 to 0.86, p <0.00001). Recent data on novel oral anticoagulants suggested a higher efficacy of these agents compared with warfarin (HR 0.80, 95% CI 0.66 to 0.96, p = 0.02) and aspirin (HR 0.32, 95% CI 0.19 to 0.55, p <0.0001) in treating non-end-stage CKD. In conclusion, the presence of CKD in patients with AF is associated with an almost 50% increased thromboembolic risk, which can be effectively decreased with appropriate antithrombotic therapy. Further prospective studies are needed to better evaluate the interest of anticoagulation in patients with severe CKD.

Atrial fibrillation in congestive heart failure

Atrial fibrillation (AF) and heart failure (HF) are common and interrelated conditions, each promoting the other, and both associated with increased mortality. HF leads to structural and electrical atrial remodeling, thus creating the basis for the development and perpetuation of AF; and AF may lead to hemodynamic deterioration and the development of tachycardia-mediated cardiomyopathy. Stroke prevention by antithrombotic therapy is crucial in patients with AF and HF. Of the 2 principal therapeutic strategies to treat AF, rate control and rhythm control, neither has been shown to be superior to the other in terms of survival, despite better survival in patients with sinus rhythm compared with those in AF. Antiarrhythmic drug toxicity and poor efficacy are concerns. Catheter ablation of AF can establish sinus rhythm without the risks of antiarrhythmic drug therapy, but has important procedural risks, and data from randomized trials showing a survival benefit of this treatment strategy are still lacking. In intractable cases, ablation of the atrioventricular junction and placement of a permanent pacemaker is a treatment alternative; and biventricular pacing may prevent or reduce the negative consequences of chronic right ventricular pacing.

The effectiveness and safety of d,l-sotalol in the ambulatory treatment of atrial fibrillation and flutter

Data on short and long term efficacy and safety of d,l sotalol in patients with atrial fibrillation or atrial flutter is limited. The aims of this study were to (1) assess the antiarrhythmic efficacy of d,l sotalol maintaining normal sinus rhythm in patients with refractory atrial fibrillation or flutter, (2) evaluate the efficacy of d,l sotalol in preventing recurrences of paroxysmal atrial fibrillation or flutter, (3) evaluate the control of ventricular rate in patients with paroxysmal or refractory atrial fibrillation or flutter unsuccessfully treated with other antiarrhythmic agents, (4) determine predictors of efficacy (5) assess the safety of d,l sotalol in this setting. Two hundred patients with chronic or paroxysmal atrial fibrillation or atrial flutter or both, who had failed one to six previous antiarrhythmic drug trials were treated with d,l sotalol 80 to 440 mg/day orally. Fifty four percent was female, age 47 +/- 16 years (range 7-79), follow up period 7 +/- 7 months (range 1 to 14 months), 79% of patients had the arrhythmia for more than one year. The atrial fibrillation in 37.5% of patients was chronic and paroxysmal in 23.5. The atrial flutter was chronic in 31% of patients and paroxysmal in 8%. Eighty two percent of patients was in functional class I (NYHA) and 82% had cardiac heart disease: left atrial (LA) size 44 +/- 10 mm, right atrial (RA) size 37 +/- 7 mm and left ventricular ejection fraction (LVEF) 58 +/- 8%. Total success was achieved in 58% of patients (atrial fibrillation 40% and 18% in atrial flutter), partial success in 38% (atrial fibrillation in 18% and 20% in atrial flutter) and 4% of patients failure. It was p < 0.07 when compared total success vs partial success among atrial fibrillation and atrial flutter groups. Patients with cardiac heart disease responded worst (p = 0.10) to the drug than those without it, specially if the heart was dilated. We concluded that d,l sotalol has moderate efficacy to convert and maintain normal sinus rhythm, as well as it acts controlling paroxysmal relapses and ventricular heart rate.

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

In clinical practice many patients with atrial fibrillation (AF) at high thromboembolic risk fail to receive adequate oral anticoagulation (OAC) [1]. The complex management of anticoagulant therapy [frequent international normalised ratio (INR) monitoring because of narrow therapeutic window, interaction with food and alcohol, concomitant medications and comorbities], the overestimation of bleeding risk and the underestimation of stroke risk, may partially explain physicians' reluctance to prescribe anticoagulation. In the current issue of Age and Ageing, Pugh and Mead [2] report a systematic review on physicians' attitudes concerning anticoagulant treatment among AF patients. Through surveys (questionnaire, clinical vignette and interview) on hypothetical case scenarios, they have identified the barriers to effective anticoagulant prescription, as follows: increasing age, bleeding risk or previous bleeding, fall risk, co-morbidities (e.g. chronic alcoholism or cognitive impairment) and lack of compliance. In particular, advanced age has been reported as the most striking reason for with-holding anticoagulation, while risk of falls and previous bleeding are also disproportionate barriers to warfarin prescription.

Educational and behavioural interventions for anticoagulant therapy in patients with atrial fibrillation

Background Current guidelines recommend oral anticoagulation therapy for patients with atrial fibrillation who are at moderate-to-high risk of stroke, however anticoagulation control (time in therapeutic range (TTR)) is dependent on many factors. Educational and behavioural interventions may impact on patients’ ability to maintain their International Normalised Ratio (INR) control. Objectives To evaluate the effects on TTR of educational and behavioural interventions for oral anticoagulation therapy (OAT) in patients with atrial fibrillation (AF). Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) and the Database of Abstracts of Reviews of Effects (DARE) in The Cochrane Library (2012, Issue 7 of 12), MEDLINE Ovid (1950 to week 4 July 2012), EMBASE Classic + EMBASE Ovid (1947 to Week 31 2012), PsycINFO Ovid (1806 to 2012 week 5 July) on 8 August 2012 and CINAHL Plus with Full Text EBSCO (to August 2012) on 9 August 2012. We applied no language restrictions. Selection criteria The primary outcome analysed was TTR. Secondary outcomes included decision conflict (patient's uncertainty in making health-related decisions), percentage of INRs in the therapeutic range, major bleeding, stroke and thromboembolic events, patient knowledge, patient satisfaction, quality of life (QoL), and anxiety. Data collection and analysis The two review authors independently extracted data. Where insufficient data were present to conduct a meta-analysis, effect sizes and confidence intervals (CIs) of the included studies were reported. Data were pooled for two outcomes, TTR and decision conflict. Main results Eight trials with a total of 1215 AF patients (number of AF participants included in the individual trials ranging from 14 to 434) were included within the review. Studies included education, decision aids, and self-monitoring plus education. For the primary outcome of TTR, data for the AF participants in two self-monitoring plus education trials were pooled and did not favour self-monitoring plus education or usual care in improving TTR, with a mean difference of 6.31 (95% CI -5.63 to 18.25). For the secondary outcome of decision conflict, data from two decision aid trials favoured usual care over the decision aid in terms of reducing decision conflict, with a mean difference of -0.1 (95% CI -0.2 to -0.02). Authors' conclusions This review demonstrated that there is insufficient evidence to draw definitive conclusions regarding the impact of educational or behavioural interventions on TTR in AF patients receiving OAT. Thus, more trials are needed to examine the impact of interventions on anticoagulation control in AF patients and the mechanisms by which they are successful. It is also important to explore the psychological implications for patients suffering from this long-term chronic condition.

Educational and behavioural interventions for anticoagulant therapy in patients with atrial fibrillation

background Current guidelines recommend oral anticoagulation therapy for patients with atrial fibrillation who are at moderate-to-high risk of stroke, however anticoagulation control (time in therapeutic range (TTR)) is dependent on many factors. Educational and behavioural interventions may impact on patients’ ability to maintain their International Normalised Ratio (INR) control. Objectives To evaluate the effects on TTR of educational and behavioural interventions for oral anticoagulation therapy (OAT) in patients with atrial fibrillation (AF). Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) and the Database of Abstracts of Reviews of Effects (DARE) in The Cochrane Library (2012, Issue 7 of 12), MEDLINE Ovid (1950 to week 4 July 2012), EMBASE Classic + EMBASE Ovid (1947 to Week 31 2012), PsycINFO Ovid (1806 to 2012 week 5 July) on 8 August 2012 and CINAHL Plus with Full Text EBSCO (to August 2012) on 9 August 2012. We applied no language restrictions. Selection criteria The primary outcome analysed was TTR. Secondary outcomes included decision conflict (patient's uncertainty in making health-related decisions), percentage of INRs in the therapeutic range, major bleeding, stroke and thromboembolic events, patient knowledge, patient satisfaction, quality of life (QoL), and anxiety. Data collection and analysis The two review authors independently extracted data. Where insufficient data were present to conduct a meta-analysis, effect sizes and confidence intervals (CIs) of the included studies were reported. Data were pooled for two outcomes, TTR and decision conflict. Main results Eight trials with a total of 1215 AF patients (number of AF participants included in the individual trials ranging from 14 to 434) were included within the review. Studies included education, decision aids, and self-monitoring plus education. For the primary outcome of TTR, data for the AF participants in two self-monitoring plus education trials were pooled and did not favour self-monitoring plus education or usual care in improving TTR, with a mean difference of 6.31 (95% CI -5.63 to 18.25). For the secondary outcome of decision conflict, data from two decision aid trials favoured usual care over the decision aid in terms of reducing decision conflict, with a mean difference of -0.1 (95% CI -0.2 to -0.02). Authors' conclusions This review demonstrated that there is insufficient evidence to draw definitive conclusions regarding the impact of educational or behavioural interventions on TTR in AF patients receiving OAT. Thus, more trials are needed to examine the impact of interventions on anticoagulation control in AF patients and the mechanisms by which they are successful. It is also important to explore the psychological implications for patients suffering from this long-term chronic condition.

Developing a complex educational–behavioural intervention:the TREAT intervention for patients with atrial fibrillation

This article describes the theoretical and pragmatic development of a patient-centred intervention for patients with atrial fibrillation (AF). Theoretical models (Common Sense Model, Necessity-Concerns Framework), clinical frameworks, and AF patient feedback contributed to the design of a one-off hour-long behaviour-change intervention package. Intervention materials consisted of a DVD, educational booklet, diary and worksheet, which were patient-centred and easy to administer. The intervention was evaluated within a randomised controlled trial. Several “active theoretical ingredients” were identified (for e.g., where patients believed their medication was less harmful they spent more time within the therapeutic range (TTR), with general harm scores predicting TTR at 6 months). Allowing for social comparison and adopting behaviour change techniques enabled accurate patient understanding of their condition and medication. The process of developing the intervention using theory-derived content and evaluation tools allowed a greater understanding of the mechanisms by which this intervention was successful. Alleviating concerns about treatment medication by educating patients can help to improve adherence. This process of intervention development could be adopted for a range of chronic illnesses and treatments. Critical elements should include the use of: (1) clinical guidelines; (2) appropriate theoretical models; (3) patient input; and (4) appropriate evaluation tools.

The well-being of relatives of patients with atrial fibrillation: a critical incident technique analysis

BACKGROUND: The well-being of relatives of patients having chronic heart diseases (CHD) has been found to be negatively affected by the patient's condition. Studies examining relatives of patients with atrial fibrillation (AF) indicate that their well-being may be affected in a similar manner, but further research is needed. AIM: To explore and describe critical incidents in which relatives of patients experience how AF affects their well-being and what actions they take to handle these situations. DESIGN AND METHOD: An explorative, descriptive design based on the critical incident technique (CIT) was used. Interviews were conducted with 19 relatives (14 women and five men) of patients hospitalised in southern Sweden due to acute symptoms of the AF. RESULTS: The well-being of relatives was found to be affected by their worries (patient-related health), as well as the sacri-ficing of their own needs (self-related health). In handling their own well-being, these relatives adjusted to and supported the patient (practical involvement), along with adjusting their own feelings and responding to the mood of the patients (emotional involvement). CONCLUSION: The well-being of relatives of patients with AF was affected depending on the patients' well-being. In their attempt to handle their own well-being, the relatives adjusted to and supported the patients. Further research is needed in order to evaluate the effects of support to relatives and patients respectively and together.

PALLAS : limiting indications for dronedarone treatment of atrial fibrillation.

Atrial fibrillation increases the risk of stroke. Dronedarone has been shown to reduce the composite of hospitalizations due to cardiovascular events or death, in subjects with intermittent atrial fibrillation or flutter. Recently, dronedarone has been tested in subjects with permanent atrial fibrillation in the PALLAS (permanent atrial fibrillation outcome study using dronedarone on top of standard therapy) trial, and this clinical trial is evaluated in this paper. PALLAS was stopped early as there was an increased incidence of cardiovascular events in the dronedarone group. Dronedarone also increased the rate of hospitalizations in PALLAS. As a result of PALLAS, dronedarone has been contraindicated in permanent atrial fibrillation. The outcomes of PALLAS highlight a discontinuity between dronedarone actions in permanent and intermittent atrial fibrillation. The mechanism(s) underlying the detrimental effects of dronedarone in permanent atrial fibrillation are unknown at present and need to be investigated.

More light at the end of the tunnel – apixaban in atrial fibrillation

Introduction: Subjects with atrial fibrillation are at risk of thromboembolic events. The vitamin K antagonists (e.g., warfarin) are useful at preventing coagulation in atrial fibrillation, but are difficult to use. One of the FXa inhibitors, oral apixaban, has been tested as an anticoagulant in atrial fibrillation. Areas covered: In ARISTOTLE (Apixaban for reduction in stroke and other thromboembolic events in atrial fibrillation) apixaban was compared to warfarin in subjects with atrial fibrillation, and shown to cause a lower rate of stroke or systemic embolism and of major bleeding, than warfarin. In the AVERROES (Apixaban versus acetylsalicylic acid [ASA] to prevent stroke in atrial fibrillations patients who have failed or are unsuitable for vitamin K antagonist treatment) trial, stroke or systemic embolism occurred less often with apixaban than aspirin, whereas the occurrence of major bleeding was similar in the groups. Expert opinion: Apixaban is much easier for subjects with atrial fibrillation to use than warfarin, as it does not require regular monitoring by a health professional, with dosage adjustment. In addition to replacing warfarin in subjects with atrial fibrillation who are unable or not prepared to use warfarin, apixaban has the potential to replace warfarin more widely in the prevention of thromboembolism in subjects with atrial fibrillation.

Utility of dexmedetomidine in sedation for radiofrequency ablation of atrial fibrillation.

[Letter to the Editor] I read with great interest the article recently published in the Journal of PeriAnesthesia Nursing that examined the utility of using dexmedetomidine (DEX) as an adjunct to midazolam and fentanyl for procedural sedation and analgesia during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF).1 With the view toward advancing knowledge about more effective medications for sedation in this challenging context, I offer the following insights for readers to consider regarding this study...