Epidemiology and significance of atrial fibrillation

Left Atrial Appendage Occlusion and Its Role in Stroke Prevention

Atrial fibrillation is a frequent cardiac arrhythmia and is associated with an increased risk of cardioembolic stroke. The left atrial appendage is a finger-like extension originating from the main body of the left atrium and the main location of thrombus formation in patients with atrial fibrillation. Surgical or percutaneous left atrial appendage occlusion (LAAO) aims at preventing clot formation in the left atrial appendage. Here, we describe available surgical and percutaneous approaches to achieve LAAO and discuss the available evidence for LAAO in patients with atrial fibrillation. We discuss the role of LAAO and its role in stroke prevention in frequent scenarios in cerebrovascular medicine: LAAO as a potential alternative to oral anticoagulation in patients with a history of intracranial hemorrhage, and LAAO as a promising add-on therapy to direct oral anticoagulant therapy in patients with breakthrough stroke despite anticoagulation. Finally, we provide an outlook on currently ongoing trials that will provide further evidence in the next years.

Hypermethylation of Hif3a and Ifltd1 is associated with atrial remodeling in pressure-overload murine model

Atrial remodeling is a major pathophysiological mechanism of atrial fibrillation (AF). Atrial remodeling progresses with aging and background diseases, including hypertension, heart failure, and AF itself. However, its mechanism of action and reversibility have not been completely elucidated. In this study, we investigated the involvement of DNA methylation in atrial remodeling. Mice underwent transverse aortic constriction (TAC) to generate a pressure overload model. After 14 days, the TAC-operated mice showed a significant increase in the atrium/body weight ratio and deposition of collagen fibers in the atria. A comprehensive analysis using RNA-sequencing (RNA-Seq) and methyl-CpG-binding domain sequencing (MBD-Seq) in the left atrial tissue identified Hif3a and Ifltd1 as showing increased DNA methylation in their promoter regions and decreased RNA expression. In addition, we created a transient pressure overload model by removing the aortic constriction 3 or 7 days after the initial TAC procedure (R3 or R7 groups). A reduction in RNA expression was achieved at R3 for Hif3a and at R7 for Ifltd1. Heterozygous Dnmt1 gene-targeting mice (Dnmt1mut) showed disappearance of the reduction in RNA expression and an increase in the atrium/body weight ratio. Altogether, DNA methylation contributed to at least part of atrial remodeling in the pressure overload mouse model.

Atrial Fibrillation Surgery in Australia: Are We Doing Enough?

AIM

This study aimed to examine contemporary burden and treatment trends of atrial fibrillation (AF) in patients undergoing cardiac surgery in Australia and New Zealand. This allows comparison of contemporary practice with the Society of Thoracic Surgeons guideline recommendations for the surgical treatment of AF in patients undergoing cardiac surgery.

METHOD

A 10-year retrospective review of the Australian & New Zealand Society of Cardiac & Thoracic Surgeons National Cardiac Surgery Database was performed, examining all adult cardiac surgery patients from 2011 to 2021. Patients were grouped by the presence or absence of AF, and simple descriptive statistical analysis was performed to assess baseline demographics and premorbid condition of the patients. The incidence of AF was analysed by type of surgery. Trends for surgical treatment of AF were then analysed using simple descriptive statistics, examining isolated left atrial appendage ligation, isolated surgical ablation, and combined ligation and ablation.

RESULTS

In the last 10 years, the Australian & New Zealand Society of Cardiac & Thoracic Surgeons database has recorded 140,680 patients who underwent cardiac surgery. Atrial fibrillation (AF) was present in 21,077 patients (14%). Patients with AF were generally older (72.25 vs 66.65 years; p<0.001). Among patients undergoing cardiac surgery, AF was more common in female than in male patients (18% vs 13%, respectively). Patients with AF more often had a higher classification of dyspnoea according to the New York Heart Association and lower ejection fractions compared with their AF-free counterparts. The incidence of AF as a comorbid condition was more frequent in patients undergoing mitral valve surgery or combined coronary artery bypass grafting and valve surgery (aortic, mitral, or both) compared with those undergoing isolated coronary or aortic surgery. Only 11.90% (n=2,509) of patients with AF received a combined ablation and left atrial appendage ligation, and 19.54% (n=693) of those received a Cox-Maze IV ablation.

CONCLUSIONS

The burden of concomitant AF in patients undergoing cardiac surgery in Australia is higher than previously reported (14% vs 5%-11%). Despite strong recommendation for the surgical management of AF in patients undergoing cardiac surgery and clear evidence of its benefit, both left atrial appendage ligation and surgical ablation independently or concomitantly remain heavily underutilised in this cohort.

Characteristics of successful termination of atrial fibrillation by atrial antitachycardia pacing in patients with cardiac implantable electronic devices

Asymptomatic paroxysmal atrial fibrillation (AF) is often found in patients implanted with cardiac implantable electronic devices (CIEDs). Second-generation atrial antitachycardia pacing (A-ATP) is effective in managing AF in patients implanted with CIEDs. The purpose of this study was to evaluate the efficacy and safety of A-ATP in patients implanted with CIEDs. This was a single-center retrospective study involving 91 patients (male 46 patients, mean age 74 ± 9 years) implanted with Reactive A-ATP equipped devices (84 patients with pacemakers, 6 with ICDs, and 1 with a CRT-D). The AF burden, rate of AF termination, and details of the activation of the A-ATP were analyzed in each patient. During a mean follow-up period of 21 ± 13 months, A-ATP was activated in 45 of 91 patients (49.5%). No patients had adverse events. Although the efficacy of the A-ATP varied among the patients, the median rate of AF termination was 44%. In comparison to the A-ATP start time, "0 min" had a higher AF termination rate by the A-ATP (39.4% vs. 24.4%, P = 0.011). The rate of termination by the A-ATP was high for AF with a long cycle length and a relatively regular rhythm. A-ATP successfully terminated AF episodes in some patients implanted with CIEDs. The optimal settings of the A-ATP will be determined in future studies.

A Crowdsourced AI Framework for Atrial Fibrillation Detection in Apple Watch and Kardia Mobile ECGs

Background: Atrial fibrillation (AFib) detection via mobile ECG devices is promising, but algorithms often struggle to generalize across diverse datasets and platforms, limiting their real-world applicability. Objective: This study aims to develop a robust, generalizable AFib detection approach for mobile ECG devices using crowdsourced algorithms. Methods: We developed a voting algorithm using random forest, integrating six open-source AFib detection algorithms from the PhysioNet Challenge. The algorithm was trained on an AliveCor dataset and tested on two disjoint AliveCor datasets and one Apple Watch dataset. Results: The voting algorithm outperformed the base algorithms across all metrics: the average of sensitivity (0.884), specificity (0.988), PPV (0.917), NPV (0.985), and F1-score (0.943) on all datasets. It also demonstrated the least variability among datasets, signifying its highest robustness and effectiveness in diverse data environments. Moreover, it surpassed Apple's algorithm on all metrics and showed higher specificity but lower sensitivity than AliveCor's Kardia algorithm. Conclusions: This study demonstrates the potential of crowdsourced, multi-algorithmic strategies in enhancing AFib detection. Our approach shows robust cross-platform performance, addressing key generalization challenges in AI-enabled cardiac monitoring and underlining the potential for collaborative algorithms in wearable monitoring devices.

Changes in anticoagulation practice in subjects admitted with stroke associated with atrial fibrillation, following introduction of direct oral anticoagulants over 2013-2021

BACKGROUND

The adoption of direct oral anticoagulants (DOACs) has changed practice in prevention of stroke in atrial fibrillation (AF). We used Irish data national data on stroke and anticoagulation therapy over 9 years to investigate changes in anticoagulation practice and potential consequences on stroke prevalence and thrombolysis.

METHODS

AF, anticoagulation, thrombolysis, and stroke data from the Irish National Audit of Stroke (INAS) 2013-2021 were reviewed. The proportion of patients with ischemic stroke (IS) and intracerebral hemorrhage (IH) with known AF admitted on anticoagulation was determined. Effects on age distribution in the population and thrombolysis practice were assessed.

RESULTS

AF data were available on 34,630 of 35,241 individuals (98.3%) included in INAS; median age was 74 years and 56% were male. AF was found in 10,016 (28.9%, 9059 IS, 957 IH). 6313 had known AF prior to stroke (63.1%). The proportion all total IS due to AF decreased by 15.3% (31.3%-26.5%, chi-square = 24.6, p < 0.0001). The proportion of IH did not change significantly (21.6%-20.2%, chi-square = 1.8, p = 0.18). Over the 9 years, 3875 (38.6%) of the subjects with AF were recorded as receiving anticoagulants at admission. In 2013, 4.4% of AF-associated strokes were admitted on a DOAC and 21.4% on warfarin; by 2021, 44.1% were receiving a DOAC and 6.2% warfarin. There was a strong inverse correlation between the proportion of anticoagulated stroke patients and the total proportion of AF-associated strokes over time (r = -0.82, p = 0.006). In contrast, no correlation was found between increasing DOAC usage and IH (r = 0.14, p = 0.71). Increased anticoagulation usage correlated with a reduction in patients ⩾ 80 years (r = -0.83, p = 0.006) and also correlated with a relative reduction of 30.1% in subjects thrombolysed <4 h from onset (r = -0.89, p = 0.001).

CONCLUSION

DOACs have led to increased use of anticoagulation, but warfarin use fell by two-thirds. There has been a reduction in the proportion of AF-associated IS without a noticeable increase in IH. Increased anticoagulation correlated with reduced numbers of strokes in those >80 years and in the proportion of patients thrombolysed.

Off-Target Effects of Cancer Therapy on Development of Therapy-Induced Arrhythmia: A Review

BACKGROUND

Advances in cancer therapeutics have improved overall survival and prognosis in this patient population; however, this has come at the expense of cardiotoxicity including arrhythmia.

SUMMARY

Cancer and its therapies are associated with cardiotoxicity via several mechanisms including inflammation, cardiomyopathy, and off-target effects. Among cancer therapies, anthracyclines and tyrosine kinase inhibitors (TKIs) are particularly known for their pro-arrhythmia effects. In addition to cardiomyopathy, anthracyclines may be pro-arrhythmogenic via reactive oxygen species (ROS) generation and altered calcium handling. TKIs may mediate their cardiotoxicity via inhibition of off-target tyrosine kinases. Ibrutinib-mediated inhibition of CSK may be responsible for the increased prevalence of atrial fibrillation. Further investigation is warranted to further elucidate the mechanisms behind arrhythmias in cancer therapies.

KEY MESSAGES

Arrhythmias are a common cardiotoxicity of cancer therapies. Cancer therapies may induce arrhythmias via off-target effects. Understanding the mechanisms underlying arrhythmogenesis associated with cancer therapies may help design cancer therapies that can avoid these toxicities.

Outcomes of Patients With Atrial Fibrillation Following Thrombectomy for Stroke: A Systematic Review and Meta-analysis

Importance

Patients with atrial fibrillation (AF) treated with mechanical thrombectomy (MT) for acute ischemic stroke (AIS) have been reported to experience worse outcomes compared with patients without AF.

Objective

To assess differences between patients with AF and their counterparts without AF treated with MT for AIS, focusing on safety outcomes, clinical outcomes, and baseline characteristics in both groups.

Data Sources

A systematic literature review of the English language literature from inception to July 14, 2022, was conducted using Web of Science, Embase, Scopus, and PubMed databases.

Study Selection

Studies that focused on patients with and without AF treated with MT for AIS were included. Multiple reviewers screened studies to identify studies included in analysis.

Data Extraction and Synthesis

Data were extracted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline to ensure accuracy. Data were pooled using a random-effects model.

Main Outcomes and Measures

The primary outcome of interest was rate of modified Rankin Scale (mRS) scores of 0 to 2 at 90 days. Secondary outcomes of interest included rates of successful reperfusion, defined as thrombolysis in cerebral infarction (TICI) scores of 2b to 3, 90-day mortality, symptomatic intracranial hemorrhage (SICH), and baseline patient characteristics.

Results

Of 1696 initially retrieved studies, 10 studies were included, with 6543 patients. Patients with AF were a mean of 10.17 (95% CI, 8.11-12.23) years older (P < .001) and had higher rates of hypertension (OR, 1.89 [95% CI, 1.57-2.27]; P < .001) and diabetes (OR, 1.16 [95% CI, 1.02-1.31]; P = .02). Overall, there were comparable rates of mRS scores of 0 to 2 between patients with AF and patients without AF (odds ratio [OR], 0.72 [95% CI, 0.47-1.10]; P = .13), with significant heterogeneity among the included studies. After sensitivity analysis, the rate of mRS scores of 0 to 2 was significantly lower among patients with AF (OR, 0.65 [95% CI, 0.52-0.81]; P < .001). Successful reperfusion rates were similar between the groups (OR, 1.11 [95% CI, 0.78-1.58]; P = .57). The rate of SICH was similar between groups (OR, 1.05 [95% CI, 0.84-1.31]; P = .68). Mortality was significantly higher in the AF group (OR, 1.47 [95% CI, 1.12-1.92]; P = .005).

Conclusions and Relevance

In this systematic review and meta-analysis, patients with AF experienced worse 90-day outcomes, even in the setting of similar rates of successful reperfusion. This was likely associated with greater age and greater rates of comorbidities among patients with AF.

Atrial Fibrillation Detection with Low Signal-to-Noise Ratio Data Using Artificial Features and Abstract Features

Detecting atrial fibrillation (AF) of short single-lead electrocardiogram (ECG) with low signal-to-noise ratio (SNR) is a key of the wearable heart monitoring system. This study proposed an AF detection method based on feature fusion to identify AF rhythm (A) from other three categories of ECG recordings, that is, normal rhythm (N), other rhythm (O), and noisy (∼) ECG recordings. So, the four categories, that is, N, A, O, and ∼ were identified from the database provided by PhysioNet/CinC Challenge 2017. The proposed method first unified the 9 to 60 seconds unbalanced ECG recordings into 30 s segments by copying, cutting, and symmetry. Then, 24 artificial features including waveform features, interval features, frequency-domain features, and nonlinear feature were extracted relying on prior knowledge. Meanwhile, a 13-layer one-dimensional convolutional neural network (1-D CNN) was constructed to yield 38 abstract features. Finally, 24 artificial features and 38 abstract features were fused to yield the feature matrix. Random forest was employed to classify the ECG recordings. In this study, the mean accuracy (Acc) of the four categories reached 0.857. The F ₁ of N, A, and O reached 0.837. The results exhibited the proposed method had relatively satisfactory performance for identifying AF from short single-lead ECG recordings with low SNR.

Convolutional neural networks predict the onset of paroxysmal atrial fibrillation: Theory and applications

In this study, we aimed to detect paroxysmal atrial fibrillation episodes before they occur so that patients can take precautions before putting their and others' lives in potentially life-threatening danger. We used the atrial fibrillation prediction database, open data from PhysioNet, and assembled our process based on convolutional neural networks. Conventional heart rate variability features are calculated from time-domain measures, frequency-domain measures using power spectral density estimations, time-frequency-domain measures using wavelet transform, and nonlinear Poincaré plot measures. In addition, we also applied an alternative heart rate normalization, which gave promising results only in a few studies, before calculating these heart rate variability features. We used these features directly and their normalized versions using min-max normalization and z-score normalization methods. Thus, heart rate variability features extracted from six different combinations of these normalizations, in addition to no normalization cases, were applied to the convolutional neural network classifier. We tuned the classifiers' hyperparameters using 90% of feature sets and tested the classifiers' performances using 10% of feature sets. The proposed approach resulted in 87.76% accuracy, 91.30% precision, 80.04% recall, and 87.50% f1-score in heart rate variability with z-score feature normalization. When the heart rate normalization was also utilized, the suggested method gave 100% accuracy, 100% precision, 100% recall, and 100% f1-score in heart rate variability with z-score feature normalization. The proposed method with heart rate normalization and z-score normalization methods resulted in better classification performance than similar studies in the literature. By comparing the existing studies, we conclude that our approach provides a much better tool to determine a near-future paroxysmal atrial fibrillation episode. However, although the achieved benchmarks are impressive, we note that the approach needs to be supported by other studies and on other datasets before clinical trials.

Mitral Regurgitation and Prognosis After Non-ST-Segment Elevation Myocardial Infarction in Very Old Patients

BACKGROUND/OBJETCTIVES

Mitral regurgitation (MR)after an acute coronary syndrome is associated with a poor prognosis. However,the prognostic impact of MR in elderly patients with non-ST-segment elevation myocardialinfarction (NSTEMI) has not been well addressed.

DESIGN

Prospective registry.

SETTING AND PARTICIPANTS

The multicenter LONGEVO-SCA prospective registry included 532 unselected NSTEMI patients aged ≥80 years.

MEASUREMENTS

MR was quantified using echocardiography during admission in 497 patients. They were classified in two groups: significant (moderate or severe) or not significant MR (absent or mild). We evaluated the impact of MR status on mortality or readmission at 6 months.

RESULTS

Mean age was 84.3±4.1 years, and 308 (61.9%) were males. A total of 108 patients (21.7%) had significant MR. Compared with those without significant MR, they were older and showed worse baseline clinical status, with higher frailty, disability, and risk of malnutrition. They also had lower systolic blood pressure, higher heart rate, worse Killip class, lower left ventricular ejection fraction, and higher pulmonary pressure on admission, as well as more often new onset atrial fibrillation (all p values = 0.001). Patients with significant MR also had higher in-hospital mortality (4.6% vs. 1.3%, p = 0.04), longer hospital stay (median 8 [5-12] vs. 6 [4-10] days, p = 0.002), and higher mortality/readmission at 6 months (hazard ratio 1.54, 95% confidence interval 1.09-2.18, p = 0.015). However, after adjusting for potential confounders, this last association was not significant.

CONCLUSIONS

Significant MR is seen in one fifth of octogenarians with NSTEMI. Patients with significant MR have a poor prognosis, mainly determined by their baseline clinical characteristics. J Am Geriatr Soc 67:1641-1648, 2019.

Rate Versus Rhythm Control in Patients with Normal to Mild Left Atrial Enlargement: Insights from the AFFIRM Trial

Background

Atrial fibrillation is the most commonly encountered sustained arrhythmia and is associated with significant morbidity and mortality. Several trials have demonstrated that no mortality benefit exists when choosing a rhythm-control strategy over a rate-control strategy, with some trials suggesting an increase in mortality. Using the AFFIRM trial database we sought to determine the effect of rhythm control strategy in patients with normal or mild atrial enlargement.

Methods

AFFIRM Trial database was used to evaluate the effect of rhythm-control strategy compared to rate-control strategy in a subgroup of patients with normal to mild left atrial (LA) enlargement. The primary outcome measures of this study were all-cause mortality, cardiovascular mortality, non-cardiovascular mortality, and hospitalization/ED visit.

Results

We identified a subgroup of subjects from the AFFIRM trial with normal or mild LA enlargement (n=2022 of 4060 total subjects). Subjects in the rhythm-control group(n= 1022) had an increased risk of all-cause mortality by 34% (RR 1.34, 95% CI 1.08-1.67; P=0.007) and hospitalization/ED visits by 10% (RR 1.10, 95% CI 1.05-2.16; P=<0.001) compared to rate control group(n= 1000).

Conclusion

This study demonstrated that rhythm-control strategy increases the risk of mortality and hospitalization in a subgroup of patients with normal to mild atrial enlargement compared to rate-control strategy. Amiodarone use in this subgroup of patients likely drove these findings.

Dietary sodium intake is associated with long-term risk of new-onset atrial fibrillation

BACKGROUND

The association between dietary salt intake and hypertension has been well documented. We evaluated the association between dietary sodium intake and the incidence of new-onset atrial fibrillation (AF) during a mean follow-up of 19 years among 716 subjects from the Oulu Project Elucidating Risk of Atherosclerosis (OPERA) cohort.

MATERIAL AND METHODS

Dietary sodium intake was evaluated from a seven-day food record. The diagnosis of AF (atrial flutter included) was made if ICD-10 code I48 was listed in the hospital discharge records during follow-up.

RESULTS

In the Kaplan-Meier curves, when quartiles of sodium consumption were considered, the cumulative proportional probabilities for AF events were higher in the highest (4th) quartile (16.8%) than in the lower quartiles (1st 6.7%, 2nd 7.3% and 3rd 10.6%) (p = .003). In the Cox regression analysis, sodium consumption (g/1000 kcal) as a continuous variable was independently associated with AF events (Hazard Ratio = 2.1 (95% CI, 1.2 to 3.7) p =.015) when age, body mass index, smoking (pack-years), office systolic blood pressure, left atrium diameter, left ventricular mass index and the use of any antihypertensive therapy were added as covariates.

CONCLUSIONS

These findings indicate that sodium intake is associated with the long-term risk of new-onset AF. Further confirmatory studies are needed. Key messages Sodium consumption correlated positively with CV risk factors: age, smoking, SBP, BMI and LDL-cholesterol. When quartiles of sodium consumption were considered, the AF incidence was higher in the highest quartile compared to lower quartiles. Sodium consumption as a continuous variable was independently associated with AF events when age, BMI, smoking, SBP, LAD, LVMI and the use of any antihypertensive therapy were considered.

Spotlight on unmet needs in stroke prevention: The PIONEER AF-PCI, NAVIGATE ESUS and GALILEO trials

Atrial fibrillation (AF) is a major healthcare concern, being associated with an estimated five-fold risk of ischaemic stroke. In patients with AF, anticoagulants reduce stroke risk to a greater extent than acetylsalicylic acid (ASA) or dual antiplatelet therapy (DAPT) with ASA plus clopidogrel. Non-vitamin K antagonist oral anticoagulants (NOACs) are now a widely-accepted therapeutic option for stroke prevention in non-valvular AF (NVAF). There are particular patient types with NVAF for whom treatment challenges remain, owing to sparse clinical data, their high-risk nature or a need to harmonise anticoagulant and antiplatelet regimens if co-administered. This article focuses on three randomised controlled trials (RCTs) that are investigating the utility of rivaroxaban, a direct, oral, factor Xa inhibitor, in additional areas of stroke prevention where data for anticoagulants are lacking: oPenlabel, randomized, controlled, multicentre study explorIng twO treatmeNt stratEgiEs of Rivaroxaban and a dose-adjusted oral vitamin K antagonist treatment (PIONEER AF-PCI); New Approach riVaroxoban Inhibition of factor Xa in a Global trial vs Aspirin to prevenT Embolism in Embolic Stroke of Undetermined Source (NAVIGATE ESUS); and Global study comparing a rivAroxaban-based antithrombotic strategy to an antipLatelet-based strategy after transcatheter aortIc vaLve rEplacement to Optimize clinical outcomes (GALILEO). Data from these studies present collaborative efforts to build upon existing registrational Phase III data for rivaroxaban, driving the need for effective and safe treatment of a wider range of patients for stroke prevention.

Association between Air Pollution and Emergency Room Visits for Atrial Fibrillation

Despite the large prevalence in the population, possible factors responsible for the induction of atrial fibrillation (AF) events in susceptible individuals remain incompletely understood. We investigated the association between air pollution levels and emergency department admissions for AF in Rome. We conducted a 14 years’ time-series study to evaluate the association between the daily levels of air pollution (particulate matter, PM₁₀ and PM_2.5, and nitrogen dioxide, NO₂) and the daily count of emergency accesses for AF (ICD-9 code: 427.31). We applied an over-dispersed conditional Poisson model to analyze the associations at different lags after controlling for time, influenza epidemics, holiday periods, temperature, and relative humidity. Additionally, we evaluated bi-pollutant models by including the other pollutant and the influence of several effect modifiers such as personal characteristics and pre-existing medical conditions. In the period of study, 79,892 individuals were admitted to the emergency departments of Rome hospitals because of AF (on average, 15.6 patients per day: min = 1, max = 36). Air pollution levels were associated with increased AF emergency visits within 24 h of exposure. Effect estimates ranged between 1.4% (0.7–2.3) for a 10 µg/m³ increase of PM₁₀ to 3% (1.4–4.7) for a 10 µg/m³ increase of PM_2.5 at lag 0–1 day. Those effects were higher in patients ≥75 years for all pollutants, male patients for PM₁₀, and female patients for NO₂. The presence of previous cardiovascular conditions, but not other effect modifiers, increase the pollution effects by 5–8% depending on the lag. This study found evidence that air pollution is associated with AF emergency visits in the short term.

Trends in the prevalence and management of pre-stroke atrial fibrillation, the South London Stroke Register, 1995-2014

Background

Previous studies have found low use of anticoagulation prior to stroke, in people with atrial fibrillation (AF). This study examined data on patients with AF-related stroke from a population-based stroke register, and sought to examine changes in management of AF prior to stroke, and reasons for suboptimal treatment, in those who were known to be at a high risk of stroke.

Methods

The South London Stroke Register (SLSR) is an ongoing population-based register recording first-in-a-lifetime stroke. Trends in the prevalence of AF, and antithrombotic medication prescribed before the stroke, were investigated from 1995 to 2014. Multivariable logistic regression analyses were conducted to assess the factors associated with appropriate management.

Results

Of the 5041 patients on the register, 816 (16.2%) were diagnosed with AF before their stroke. AF related stroke increased substantially among Black Carribean and Black African patients, comprising 5% of the overall cohort in 1995–1998, increasing to 25% by 2011–2014 (p<0.001). Anticoagulant prescription in AF patients at high-risk of stroke (CHADS2 score [> = 2]) increased from 9% (1995–1998) to 30% (2011–2014) (p<0.001). Antiplatelet prescription was more commonly prescribed throughout all time periods (43% to 64% of high-risk patients.) Elderly patients (>65) were significantly less likely to be prescribed an anticoagulant, with ethnicity, gender and deprivation showing no association with anticoagulation.

Conclusions

Most AF-related strokes occurred in people who could have been predicted to be at high risk before their stroke, yet were not prescribed optimal preventative treatment. The elderly,despite being at highest stroke risk, were rarely prescribed anticoagulants.

Patient Preferences for Oral Anticoagulation Therapy in Atrial Fibrillation: A Systematic Literature Review

OBJECTIVES

Since the introduction of non-vitamin K antagonist (VKA) oral anticoagulants (NOACs), an additional treatment option, apart from VKAs, has become available for stroke prevention in patients with atrial fibrillation (AF). For various reasons, it is important to consider patients' preferences regarding type of medication, particularly in view of the established relationship between preferences towards treatment, associated burden of treatment, and treatment adherence. This review aimed to systematically analyse the scientific literature assessing the preferences of AF patients with regard to long-term oral anticoagulant (OAC) treatment.

METHODS

We searched the MEDLINE, Scopus and EMBASE databases (from 1980 to 2015), added records from reference lists of publications found, and conducted a systematic review based on all identified publications. Outcomes of interest included any quantitative information regarding the opinions or preferences of AF patients towards OAC treatment, ideally specified according to different clinical or convenience attributes describing different OAC treatment options.

RESULTS

Overall, 27 publications describing the results of studies conducted in 12 different countries were included in our review. Among these, 16 studies analysed patient preferences towards OACs in general. These studies predominantly assessed which benefits (mainly lower stroke risk) AF patients would require to tolerate harms (mainly higher bleeding risk) associated with an OAC. Most studies showed that patients were willing to accept higher bleeding risks if a certain threshold in stroke risk reduction could be reached. Nevertheless, most of the publications also showed that the preferences of AF patients towards OACs may differ from the perspective of clinical guidelines or the perspective of physicians. The remaining 11 studies included in our review assessed the preferences of AF patients towards specific OAC medication options, namely NOACs versus VKAs. Our review showed that AF patients prefer easy-to-administer treatments, such as treatments that are applied once daily without any food/drug interactions and without the need for bridging and frequent blood controls.

CONCLUSION

Stroke risk reduction and a moderate increase in the risk of bleeding are the most important attributes for an AF patient when deciding whether they are for or against OAC treatment. If different anticoagulation options have similar clinical characteristics, convenience attributes matter to patients. In this review, AF patients favour attribute levels that describe NOAC treatment.

The burden and implications of preoperative atrial fibrillation in Australian heart valve surgery patients

BACKGROUND

Atrial fibrillation (AF) is the most common preoperative arrhythmia in heart valve surgery patients and its prevalence is rising. This study aims to investigate the impact of AF on valve surgery early complications and survival and on valve disease of different aetiologies and populations with particular reference to Indigenous Australians with rheumatic heart disease (RHD).

METHODS

The Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database was analysed to determine the association between preoperative AF and valve surgery outcome. Its association with demographics, co-morbidities, preoperative status and short and long term outcome was assessed.

RESULTS

Outcome of 1594 RHD and 19,029 non-RHD-related surgical procedures was analysed. Patients with preoperative AF were more likely to be older, female, Indigenous, to have RHD and to bear a greater burden of comorbidities. Patients with RHD and preoperative AF had a longer hospital stay and were more likely to require reoperation. Adjusted short (OR 1.4, 95% CI 1.2-1.7) and long term (HR 1.5, 95% CI 1.3-1.7) survival was inferior for patients with non-RHD preoperative AF but was no different for Indigenous and non-Indigenous Australians with RHD.

CONCLUSIONS

In this prospective Australian study, patients with valve disease and preoperative AF had inferior short and long term survival. This was particularly the case for patients with non-RHD valve disease. Earlier intervention or more aggressive AF management should be investigated as mechanisms for enhancing postoperative outcomes. This may influence treatment choice and the need for ongoing anticoagulation.

Does Celecoxib Potentiate the Anticoagulant Effect of Warfarin? A Randomized, Double-Blind, Controlled Trial

Background:

The management of patients who are receiving warfarin therapy and have musculoskeletal problems that require treatment with a nonsteroidal antiinflammatory drug (NSAID) is problematic because NSAID use may increase the risk for bleeding. Cyclooxygenase-2 selective NSAIDs such as celecoxib may be less likely to promote gastrointestinal bleeding; however, there are concerns that they could potentiate the anticoagulation effect of warfarin.

Objective:

To determine whether celecoxib potentiates the anticoagulant effect of warfarin, as measured by the international normalized ratio (INR).

Methods:

We performed a randomized, controlled, crossover trial to assess the effect on INR of celecoxib versus codeine (control treatment) in 15 patients who were receiving warfarin therapy and required analgesic treatment for osteoarthritis. During Phase 1 of the study, patients were randomly allocated to receive celecoxib 200 mg/day or codeine phosphate 7–15 mg 3–4 times daily for 5 weeks. During Phase 2 of the study, patients stopped the first study medication and started the other study medication; there was no drug-free interval between phases. Weekly INR testing was performed during the 10 week study period. Adopting the intent-to-treat principle, we used generalized estimating equations to analyze the data.

Results:

There was no significant difference in the mean INR values during each 5 week treatment period when patients received either celecoxib or codeine. There was, therefore, insufficient evidence to reject the hypothesis that these 2 treatments had an equal effect on the INR (mean difference [95% CI] 0.10 [-0.04 to 0.24]; p=0.16) based on mean imputation. This finding was confirmed after we repeated the analysis with multiple imputations (mean difference [95% CI] 0.093 [-0.16 to 0.35]; p = 0.47).

Conclusions:

Our results suggest that treatment with celecoxib does not potentiate the INR when taken with warfarin. Larger randomized trials are warranted to address the effects of coadministered warfarin and celecoxib on clinical outcomes.

Cardiovascular risk profile and management of atrial fibrillation in India: Real world data from RealiseAF survey

BACKGROUND

Atrial fibrillation (AF) is the most common sustained arrhythmia with high risk for many cardiovascular (CV) complications. Adherence to recommended management guidelines is important to avoid complications. In India, there is little knowledge on how AF is managed in real world.

METHODS

This is a cross-sectional study of patients in India enrolled in RealiseAF survey between February 2010 and March 2010 with a diagnosis of AF within the last 12 months.

RESULTS

From 15 centers, 301 patients {mean age 59.9 years (14.4); 52.5% males} were recruited. AF was controlled in 50% of patients with 77 (26.7%) in sinus rhythm and 67 (23.3%) with heart rate <80beats/min. Hypertension (50.8%), valvular heart disease (40.7%), heart failure (25.9%), and diabetes (20.4%) were the most common underlying CV diseases. Increased risk for stroke (CHADS2 score≥2) was present in 36.6%. Most of the patients (85%) were symptomatic. AF was paroxysmal, persistent, and permanent in 28.7%, 22.7%, and 34.3% respectively. In 14%, AF was diagnosed as first episode. Forty-six percent of patients had rate control, 35.2% rhythm control, 0.3% both strategies, and 18.4% received no therapy for AF before the visit. At the end of the visit, adoption to rate control strategy increased to 52.3% and patients with no therapy decreased to 7%.

CONCLUSION

AF in India is not adequately controlled. Concomitant CV risk factors and risk of stroke are high. The study underscores the need for improved adoption of guideline-directed management for optimal control of AF and reducing the risk of stroke.

Patient Preferences for Oral Anticoagulation Therapy in Atrial Fibrillation: A Systematic Literature Review

OBJECTIVES

Since the introduction of non-vitamin K antagonist (VKA) oral anticoagulants (NOACs), an additional treatment option, apart from VKAs, has become available for stroke prevention in patients with atrial fibrillation (AF). For various reasons, it is important to consider patients' preferences regarding type of medication, particularly in view of the established relationship between preferences towards treatment, associated burden of treatment, and treatment adherence. This review aimed to systematically analyse the scientific literature assessing the preferences of AF patients with regard to long-term oral anticoagulant (OAC) treatment.

METHODS

We searched the MEDLINE, Scopus and EMBASE databases (from 1980 to 2015), added records from reference lists of publications found, and conducted a systematic review based on all identified publications. Outcomes of interest included any quantitative information regarding the opinions or preferences of AF patients towards OAC treatment, ideally specified according to different clinical or convenience attributes describing different OAC treatment options.

RESULTS

Overall, 27 publications describing the results of studies conducted in 12 different countries were included in our review. Among these, 16 studies analysed patient preferences towards OACs in general. These studies predominantly assessed which benefits (mainly lower stroke risk) AF patients would require to tolerate harms (mainly higher bleeding risk) associated with an OAC. Most studies showed that patients were willing to accept higher bleeding risks if a certain threshold in stroke risk reduction could be reached. Nevertheless, most of the publications also showed that the preferences of AF patients towards OACs may differ from the perspective of clinical guidelines or the perspective of physicians. The remaining 11 studies included in our review assessed the preferences of AF patients towards specific OAC medication options, namely NOACs versus VKAs. Our review showed that AF patients prefer easy-to-administer treatments, such as treatments that are applied once daily without any food/drug interactions and without the need for bridging and frequent blood controls.

CONCLUSION

Stroke risk reduction and a moderate increase in the risk of bleeding are the most important attributes for an AF patient when deciding whether they are for or against OAC treatment. If different anticoagulation options have similar clinical characteristics, convenience attributes matter to patients. In this review, AF patients favour attribute levels that describe NOAC treatment.

Prevalence of atrial fibrillation in an urban population in India: the Nagpur pilot study

OBJECTIVES

Atrial fibrillation (AF) is the most common sustained arrhythmia encountered in clinical practice with major public health impact mainly due to the increased risk of stroke. The recent Global Burden of Disease Study reported a lack of prevalence data from India. Our goal was to conduct a pilot study to evaluate the feasibility of assessing AF prevalence and stroke prophylaxis in an urban Indian community.

METHODS

A screening camp was conducted in Nagpur, India, that evaluated adults aged ≥18 years. We collected demographics, recorded blood pressure, height, weight and the 12-lead electrocardiogram (ECG). The presence of diabetes and hypertension was recorded by self-reported history. Patients diagnosed with AF were evaluated further to assess aetiology and management.

RESULTS

Of the total 4077 randomly selected, community-dwelling adults studied, 0.196% (eight patients) were found to have AF. Mean age of the population was 43.9±14.8, and 44.5% were female. The mean age of the patients with AF was 60.5±15.8 years (five females). Rheumatic heart disease was found in five patients with AF. Three patients had history of stroke (37.5%) and one had peripheral arterial thrombosis. Three patients were on warfarin, but without routine international normalised ratio (INR) monitoring. One patient was on aspirin. Five patients were on β-blockers and one on both β-blocker and digoxin.

CONCLUSIONS

The prevalence of AF was low compared with other regions of the world and stroke prophylaxis was underused. A larger study is needed to confirm these findings. This study demonstrates that larger evaluations would be feasible using the community-based techniques employed here.

Holter monitoring to detect silent atrial fibrillation in high-risk subjects: the Perugia General Practitioner Study

Atrial fibrillation (AF) is diagnosed for the first time in about 5 % of patients admitted for acute ischemic stroke. Advanced aged and arterial hypertension are risk factors for AF. We evaluated the prevalence of silent AF in subjects with advanced age and systemic arterial hypertension. Subjects of both gender, aged 65 years or more with systemic arterial hypertension were randomly identified from the patient lists of the participating general practitioners in the Perugia area, in Italy. Study subjects underwent baseline 12-lead ECG and, if this did not show AF, 48-h Holter monitoring was performed. AF was known and confirmed by 12-lead ECG in 4 out of the 308 evaluated subjects (1.3 %). Baseline 12-lead ECG showed no cases of silent AF. Holter monitoring was performed in 300 subjects, mean age 70 ± 4. Twenty-six recordings were not evaluable for the presence of artifacts; therefore, 274 subjects were included in the analysis. Holter monitoring showed AF in 27 out of 274 subjects (10 %; 95 % confidence interval 6.4-13.5 %); AF was longer than 30 s in four of the subjects. In 56 additional subjects, Holter monitoring revealed excessive supraventricular ectopic activity (20 %; 95 % confidence interval 15.3-24.7 %). Holter monitoring was able to detect silent AF in about 10 % of subjects aged 65 or above with systemic arterial hypertension. The risk of stroke associated with screened silent AF should be carefully evaluated.

The prevalence, incidence, management and risks of atrial fibrillation in an elderly Chinese population: a prospective study

BACKGROUND

There is limited information on prevalent and incident atrial fibrillation in Chinese. We aimed to investigate the prevalence, incidence, management and risks of atrial fibrillation in an elderly Chinese population.

METHODS

In a population--based prospective study in elderly (≥ 60 years) Chinese, we performed cardiovascular health examinations including a 12-lead electrocardiogram at baseline in 3,922 participants and biennially during follow-up in 2,017 participants. We collected information on vital status during the whole follow-up period.

RESULTS

The baseline prevalence of atrial fibrillation was 2.0 % (n = 34) in 1718 men and 1.6 % (n = 36) in 2204 women. During a median 3.8 years of follow-up, the incidence rate of atrial fibrillation (n = 34) was 4.9 per 1000 person-years (95 % confidence interval [CI], 3.4-6.9). In univariate analysis, both the prevalence and incidence of atrial fibrillation were higher with age advancing (P < 0.0001) and in the presence of coronary heart disease (P ≤ 0.02). Of the 104 prevalent and incident cases of atrial fibrillation, only 1 (1.0 %) received anticoagulant therapy (warfarin). These patients with atrial fibrillation, compared with those with sinus rhythm, had significantly higher risks of all-cause (n = 261, hazard ratio [HR] 1.87, 95 % CI, 1.09-3.20, P = 0.02), cardiovascular (n = 136, HR 3.78, 95 % CI 2.17-6.58, P < 0.0001) and stroke mortality (n = 44, HR 6.31, 95 % CI 2.81-14.19, P = 0.0003).

CONCLUSIONS

Atrial fibrillation was relatively frequent in elderly Chinese, poorly managed and associated with higher risks of mortality.

Prospective national study of the prevalence, incidence, management and outcome of a large contemporary cohort of patients with incident non-valvular atrial fibrillation

BACKGROUND

There are few studies of atrial fibrillation (AF) outside of North America or Europe. The aim of the present study was to assess the prevalence, incidence, management and outcomes of patients with new atrial fibrillation, in a large contemporary cohort (2004-2012) of adult patients.

METHODS AND RESULTS

The Clalit Health Services (CHS) computerized database of 2 420 000 adults, includes data of community clinic visits, hospital discharge records, medical diagnoses, medications, medical interventions, and laboratory test results. The prevalence of AF on January 1, 2004 was 71 644 (3%). Prevalence and incidence of AF increased with age and was higher in men versus women. During the study period (2004-2012) 98 811 patients developed new non-valvular AF (mean age -72, 50% women, 46% with cardiovascular disease, 6% with prior stroke). The rate of persistent warfarin use (dispensed for >3 months in a calendar year) was low (25.7%) and it increased with increasing stroke risk score. Individual Time in Therapeutic Range (TTR) among warfarin users was 42%. The incidence rate of ischemic stroke and death increased with age. The rate of stroke increased from 2 per 1000 person years in patients with CHA(2)DS(2)_VASC SCORE of 0, to 58 per 1000 person years in those with a score of 9.

CONCLUSIONS

In the present study the prevalence and incidence of AF, stroke, and death were comparable to those reported in Europe and North America. The low use of anticoagulation calls for measures to increase adherence to current treatment recommendations in order to improve outcomes.

Perioperative management of elderly patients

The older population only represents 13.7% of the US population but has grown by 21% since 2002. The centenarian population is growing at a faster rate than the total US population. This unprecedented growth has significantly increased surgical demand. The establishment of quality and performance improvement data has allowed researchers to focus attention on the older patient population, resulting in an exponential increase in studies. Although there is still much work to be done in this field, overlying themes regarding the perioperative management of elderly patients are presented in this article based on a thorough literature review.

Untreated atrial fibrillation in the United Kingdom: Understanding the barriers and treatment options

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a major preventable cause of stroke and hospitalization. Its prevalence is on the rise worldwide and experts believe it will continue to rise for the foreseeable future, due to the ageing population and increased survival from conditions associated with AF. Despite the fact that oral anticoagulation is effective in preventing strokes due to AF, there is extensive evidence suggesting this therapy remains underused. Barriers to the prescription of anticoagulation include patients' age per se, comorbidities, inadequate risk stratification, perceived risk of falls and bleeding, and the difficulty in achieving a stable international normalized ratio (INR) on warfarin. Also, asymptomatic patients with AF may not be identified and therefore not be candidates for anticoagulation. Physicians need continued better education on the identification of patients at risk of stroke and management of oral anticoagulation. This article reviews the barriers to anticoagulation in patients with AF in the United Kingdom and considers how those barriers may be overcome.

Burden of disease and cost of illness of atrial fibrillation in Portugal

INTRODUCTION AND OBJECTIVES

Atrial fibrillation is the most prevalent sustained arrhythmia. This paper estimates the burden and cost of illness attributable to atrial fibrillation in Portugal based on demographic and health statistics.

METHODS

Mortality data by cause of death came from the European Detailed Mortality Database of the World Health Organization (WHO). Hospital data were taken from the Portuguese diagnosis-related groups database. The burden of disease was measured using DALYs (disability-adjusted life years), a metric adopted by the WHO. Costs studied included resource use and lost productivity. The burden and cost of illness are those attributable to atrial fibrillation and its main complication, ischemic stroke.

RESULTS

In Portugal, 4070 deaths were attributable to atrial fibrillation in 2010, corresponding to 3.8% of all deaths. In total, the burden of disease attributable to atrial fibrillation was estimated at 23,084 DALYs: 10,521 resulting from premature deaths (1.7% of the total DALYs due to death in 2010 in Portugal), and 12,563 resulting from disability. The total estimated direct costs attributable to atrial fibrillation at 2013 prices were €115 million: €34 million for inpatient care and €81 million for outpatient care. Indirect costs resulting from lost production due to disability were estimated at €25 million.

CONCLUSIONS

Atrial fibrillation has an important social impact in Portugal due to its associated mortality and morbidity, and was responsible in 2013 for a total cost of €140 million, about 0.08% of gross domestic product.

Atrial fibrillation: an observational study with outpatients

BACKGROUND

Atrial fibrillation (AF) is the most common sustained arrhythmia with serious clinical consequences in the absence of treatment. However, there are limited data on the treatment of these patients in Argentina. The objective was to describe the therapeutic management of patients with nonacute AF by Argentinean cardiologists and to determine the incidence of clinical events after 12 months follow-up.

METHODS

The Atrial Fibrillation study in Argentina (FARAON) was an observational, descriptive, prospective, national, and multicentric study that included outpatients with AF, followed for 12 months. The study included 38 sites in Argentina. Each researcher included the first 10 patients who met the inclusion criteria of being over 21 and also being an AF carrier documented by electrocardiogram or Holter within 12 months prior to or at the time of enrollment.

RESULTS

A total of 373 patients were included, mean age 70 ± 11.5 years, 40% women; 65% had AF rhythm at the time of inclusion, 57% had permanent AF, and 56% were asymptomatic. At the time of enrollment, 40% of physicians opted for rhythm control strategy. β-blockers and amiodarone were the most used drugs. Patients with rhythm control drugs had higher success rate than those with frequency control drug therapy (80% vs 57%).

CONCLUSION

Cardiologists in Argentina receive patients with AF that are mostly permanent AF. More than half of the patients are asymptomatic. They opt primarily by controlling the pace. When choosing antiarrhythmic drugs, nearly half of them indicated amiodarone.

Renal function, attributes and coagulation treatment in atrial fibrillation (R-FACT Study): retrospective, observational, longitudinal cohort study of renal function and antithrombotic treatment patterns in atrial fibrillation patients with documented eGFR in real-world clinical practices in Germany

AIMS

This retrospective, observational, longitudinal study aimed to document the distribution, changes in renal function [measured by estimated glomerular filtration (eGFR)] and antithrombotic treatment pattern in atrial fibrillation (AF) patients in real-world settings managed by general practitioners in Germany.

METHODS AND RESULTS

Data were extracted from the German Longitudinal Patient Database. A total of 15,900 patients with AF were identified. Among 1660 having eGFR available at baseline, 3.4% had severely impaired eGFR, 9.7% and 25.6% had moderate severe decrease and moderate decrease in eGFR, respectively, and 61.3% had mildly decreased/normal eGFR. Patients with moderately and severely decreased eGFR tended to be older. The proportion of patients with a CHADS2 score ≥ 2 was 92.9% in those with severely decreased eGFR, and 87.0% and 79.1% in those with moderately severe and moderately decreased eGFR. During follow up, 52.1% of patients with severely decreased eGFR, and 26.3% to 23.7% of patients with moderately decreased eGFR were not treated by antithrombotic. When comparing baseline with follow-up eGFR, 55.0% of patients showed decreased eGFR. Age, diabetes, dyslipidaemia and history of myocardial infarction were identified as significant predictors for renal function deterioration based on results from multivariate Cox regression model.

CONCLUSIONS

Moderate-to-severe renal dysfunction is prevalent (~38%) in German AF patients with documented eGFR managed in actual clinical practices. The risk of stroke, as measured by the CHADS2 score, was associated with decreased renal function. Treatment with anticoagulation therapies decreased with decreasing renal function, despite increasing risk of stroke. Anticoagulation treatments remain suboptimal during the 12-month follow up in patients with moderate or severe renal impairment.

Saudi Atrial Fibrillation Survey

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The Saudi Atrial Fibrillation Survey registry was designed to provide epidemiological and clinical data on patients with AF. The registry included 400 consecutive patients who met the eligibility criteria. Control of AF at the time of the initial visit was achieved by 211 (52.75%) patients. Cardiovascular risk profile of the patients with AF was smoking 92 (23.5%), hypertension 253 (63.25%), diabetes 192 (48%), and dyslipidemia 173 (44%). Rate control was the most frequent management strategy (in 265 patients, 66.2%) whereas rhythm control was chosen in 48 (12%) patients. Both strategies were attempted in 5 (1.2%) patients. This is the first nationwide registry of patients with AF in Saudi Arabia. Compared to developed countries, our patients with AF are relatively young and have higher rates of diabetes and rheumatic heart disease. Rate control is the main strategy currently used for managing AF.

Update on the management of atrial fibrillation

Atrial fibrillation (AF) is a common arrhythmia, with a prevalence that increases markedly with increasing age. Presence of AF has implications for management of future stroke risk. If the patient's pulse is irregular, an electrocardiogram should be ordered. Key management decisions are whether to adopt a rhythm control or a rate control strategy and whether to initiate anticoagulation. The primary aim of a rhythm control strategy is improved symptom control. AF ablation may be considered in younger patients (aged < 65 years) with paroxysmal or early persistent AF. AF increases the risk of stroke, and anticoagulation should be considered on the basis of stroke risk - clearly indicated with a CHADS 2 score (congestive heart failure, hypertension, age ≥ 75 years, diabetes, 1 point each; previous stroke or transient ischaemic attack, 2 points) of ≥ 2 - independent of the type of AF. In most patients with AF, the benefit of stroke reduction with systemic anticoagulation will outweigh its bleeding risks. All anticoagulants and antiplatelet agents increase the risk of bleeding. However, the new oral anticoagulants tend to have an improved safety profile, particularly in regard to intracranial bleeding, and are at least as effective as warfarin for stroke prevention.

Treatment patterns associated with stroke prevention in patients with atrial fibrillation in three major cities in the People's Republic of china

BACKGROUND

Atrial fibrillation (AF) is associated with an increased risk of stroke. This study assessed treatment patterns associated with stroke prevention among patients with AF in three major cities of the People's Republic of China.

METHODS

A random sample of 2,862 medical charts for patients with AF at six tertiary hospitals located in Beijing, Shanghai, and Guangzhou between 2003 and 2008 were reviewed. Patient demographics, clinical characteristics, and treatment patterns were extracted from medical charts. Antithrombotic regimens included antiplatelets, anticoagulants, and a combination of both. Descriptive analyses were performed to summarize basic antithrombotic patterns. A logistic regression model examined demographic and clinical factors associated with antithrombotic treatment patterns.

RESULTS

Of the patient sample, 55% were male, the average age was 72 years (49% ≥75 years), 15% had valvular AF, 78% had nonvalvular AF, and the remainder had unspecified AF. CHADS2 scores ≥2 were reported for 53% of patients. Antithrombotic treatment was not received by 17% of patients during hospitalization, and 66% did not receive warfarin. Among patients with valvular or nonvalvular AF, 33%, 30%, and 20% received antiplatelet, anticoagulation, and antiplatelet plus anticoagulation treatments, respectively. For patients with CHADS2 scores of 0, 1, 2, 3, and ≥4, 52%, 42%, 28%, 21%, and 21%, respectively, were treated with warfarin. Predictors of no antithrombotic treatment included age and hospital location.

CONCLUSION

Anticoagulation therapy was underused in Chinese patients with AF. Antithrombotic treatment was not associated with stroke risk. Further studies need to examine the clinical consequences of various antithrombotic treatment patterns in Chinese patients with AF.

Associations between ambient air pollution and daily mortality among elderly persons in Montreal, Quebec

BACKGROUND

Persons with underlying health conditions may be at higher risk for the short-term effects of air pollution. We have extended our original mortality time series study in Montreal, Quebec, among persons 65 years of age and older, for an additional 10 years (1990-2003) to assess whether these associations persisted and to investigate new health conditions.

METHODS AND RESULTS

We created subgroups of subjects diagnosed with major health conditions one year before death using billing and prescription data from the Quebec Health Insurance Plan. We used parametric log-linear Poisson models within the distributed lag non-linear models framework, that were adjusted for long-term temporal trends and daily maximum temperature, for which we assessed associations with NO2, O3, CO, SO2, and particles with aerodynamic diameters 2.5 μm in diameter or less (PM2.5). We found positive associations between daily non-accidental mortality and all air pollutants but O3 (e.g., for a cumulative effect over a 3-day lag, with a mean percent change (MPC) in daily mortality of 1.90% [95% confidence interval: 0.73, 3.08%] for an increase of the interquartile range (17.56 μg m(-3)) of NO2). Positive associations were found amongst persons having cardiovascular disease (cumulative MPC for an increase equal to the interquartile range of NO2=2.67%), congestive heart failure (MPC=3.46%), atrial fibrillation (MPC=4.21%), diabetes (MPC=3.45%), and diabetes and cardiovascular disease (MPC=3.50%). Associations in the warm season were also found for acute and chronic coronary artery disease, hypertension, and cancer. There was no persuasive evidence to conclude that there were seasonal associations for cerebrovascular disease, acute lower respiratory disease (defined within 2 months of death), airways disease, and diabetes and airways disease.

CONCLUSIONS

These data indicate that individuals with certain health conditions, especially those with diabetes and cardiovascular disease, hypertension, atrial fibrillation, and cancer, may be susceptible to the short-term effects of air pollution.

Higher persistence in newly diagnosed nonvalvular atrial fibrillation patients treated with dabigatran versus warfarin

BACKGROUND

Oral anticoagulation therapy is the primary tool in reducing stroke risk in patients with nonvalvular atrial fibrillation but is underused. Patients nonpersistent with therapy contribute to this underuse. The objective of this study was to compare persistence rates in newly diagnosed nonvalvular atrial fibrillation patients treated with warfarin versus dabigatran as their oral anticoagulation.

METHODS AND RESULTS

US Department of Defense administrative claims were used to identify patients receiving warfarin or dabigatran between October 28, 2010, and June 30, 2012. Patient records were examined for a minimum of 12 months before index date to restrict the analyses to those newly diagnosed with nonvalvular atrial fibrillation and naive-to-treatment, identifying 1775 on warfarin and 3370 on dabigatran. Propensity score matching was used to identify 1745 matched pairs. Persistence was defined as time on therapy to discontinuation. Kaplan-Meier curves were used to depict persistence over time. Cox proportional hazards model was used to determine the factors significantly associated with persistence. Using a 60-day permissible medication gap, the persistence rates were higher for dabigatran than for warfarin at both 6 months (72% versus 53%) and 1 year (63% versus 39%). Patients on dabigatran with a low-to-moderate risk of stroke (CHADS2<2) or with a higher bleed risk (HEMORR2HAGES>3) had a higher likelihood of nonpersistence (hazard ratios, 1.37; 95% confidence interval, 1.17-1.60; P<0.001; and hazard ratios, 1.24; 95% confidence interval, 1.04-1.47; P=0.016).

CONCLUSIONS

Patients who initiated dabigatran treatment were more persistent than patients who began warfarin treatment. Within each cohort, patients with lower stroke risk were more likely to discontinue therapy.