Atrial fibrillation and risk of stroke: a nationwide cohort study

Association between pain and incident arrhythmias in 422,654 individuals: evidence from the UK Biobank cohort

AIMS

Pain is associated with cardiovascular disease; however, its association with incident arrhythmias is unclear. We assessed associations between different pain characteristics (pain type, chronic pain, chronic widespread pain [chronic widespread pain], chronic musculoskeletal pain [chronic musculoskeletal pain], and number of chronic pain and chronic musculoskeletal pain sites) and incident cardiac arrhythmias, overall and by subtype.

METHODS

The study included 422,654 UK Biobank participants. Pain was ascertained via a touchscreen questionnaire. The outcomes were incident arrhythmias: all cardiac arrhythmias, atrial fibrillation (AF), other (non-AF) cardiac arrhythmias, bradyarrhythmias, and ventricular arrhythmias. Multivariable Cox-proportional regression was used to investigate the associations.

RESULTS

Over a mean (SD) follow-up of 13.19 (1.96) years, 36,860 (8.72%) participants developed arrhythmia. Compared with those without pain, those with chronic localized pain and chronic widespread pain had increased risk of all cardiac arrhythmias (hazard ratio [HR] 1.13, 95% confidence interval [CI], 1.10-1.17; 1.34, 1.19-1.51), AF (1.09, 1.05-1.14; 1.33, 1.15-1.55), and other cardiac arrhythmias (1.17, 1.12-1.22; 1.41, 1.20-1.66). There was evidence of a dose-relationship between number of chronic pain sites and risk of all cardiac arrhythmias, AF and bradyarrhythmias. Effect estimates were significantly larger among participants aged <60 years than those aged ≥60 years, and larger in women than men.

CONCLUSIONS

Chronic pain was associated with cardiac arrhythmias. Whilst causation cannot be assumed in any observational study, there was evidence of both a temporal relationship and dose-relationship. These findings reinforce the need for pain management approaches that include a broad assessment of individuals' risk factors, wider health status, and appropriate vigilance for emerging conditions.

Arterial Stiffness and Markers of Atrial Myopathy

BACKGROUND

Arterial stiffness, measured using carotid-femoral pulse wave velocity (c-f PWV) and heart rate-corrected augmentation index (Aix75), is associated with cardiovascular disease, and in some studies incident atrial fibrillation (AF). In this cross-sectional study, we aimed to investigate whether arterial stiffness is associated with markers of atrial myopathy, which refers to structural and electrical changes in the atria that indicate increased AF risk.

METHODS

We included 1050 participants (age 57 ± 4.3 years, 47% males) from the population-based Swedish CArdioPulmonary bioImage Study with c-f PWV and Aix75 data. A random subsample (n = 331) underwent echocardiography. The association between arterial stiffness and atrial myopathy markers was studied using multivariable-adjusted negative binomial regression models for premature atrial complexes (PACs) on 24 h ECG, linear regression for P-wave duration and left atrial volume index (LAVi), and logistic regression models for abnormal P-wave terminal force in V1 (PWTFV1) and P-wave axis.

RESULTS

Arterial stiffness was associated with fewer PACs: incidence rate ratio (IRR) 0.45 (95% CI: 0.31 to 0.65, p < 0.001) per 1 m/s increase in c-f PWV and IRR 0.66 (95% CI: 0.49 to 0.89, p = 0.01) per % increase in Aix75. There was no association between arterial stiffness and P-wave indices, OR 1.09 (95% CI: 0.85 to 1.40), p = 0.50 for abnormal PWTFV1, and β -0.003 (-0.10 to 0.09), p = 0.95 for P-wave duration, both per 1 m/s increase in c-f PWV.

CONCLUSIONS

Arterial stiffness, measured as either c-f PWV or Aix75, was associated with fewer PACs, whereas no association was found with P-wave indices. The association between arterial stiffness and atrial myopathy is complex and merits further study.

The one-year incidence of stroke in patients with atrial fibrillation in Jordan and its associated factors

Background

An elevated risk of stroke is linked to atrial fibrillation (AF). Effective care and prevention measures for individuals with AF require an understanding of the factors impacting the incidence of stroke in this population. Evidence regarding the incidence of stroke among patients with AF is insufficient in Jordan. This study aimed to determine the incidence of stroke and its associated factors among patients with AF in Jordan.

Methods

The Jordan Atrial Fibrillation Registry JoFib was used to identify a total of 2020 AF patients meeting the study inclusion and exclusion criteria. Demographics, clinical characteristics, and the CHA2DS2-VASc score-based evaluation of stroke risk were extracted from the registry.

Results

This study encompassed 2020 participants diagnosed with AF, with 925 (45.8%) being men and 1,095 (54.2%) women. The one-year stroke incidence among the 2020 AF patients was 3.4%. Notably, stroke incidence significantly increased with age (p = 0.04) and was associated with the history of stroke (7.4% vs. 2.7%), hypertension (3.9% vs. 1.9%), and diabetes (5.1% vs. 2.1%). In the multivariate analysis, diabetes (OR = 2.6, 95% CI: 1.5-4.4, p = 0.001) and history of stroke (OR = 2.6, 95% CI: 1.5-4.6, p = 0.001) were significantly associated with stroke incidence.

Conclusion

This study emphasizes Jordan's high stroke rate among AF patients. Diabetes and prior stroke history are associated with increased odds of stroke, like all stroke patients. These results highlight the necessity for specialized management strategies among AF patients and highlight the significance of thorough risk assessment and focused interventions to reduce stroke risk in AF patients.

Temporal trends in lifetime risks of atrial fibrillation and its complications between 2000 and 2022: Danish, nationwide, population based cohort study

OBJECTIVES

To examine how the lifetime risks of atrial fibrillation and of complications after atrial fibrillation changed over time.

DESIGN

Danish, nationwide, population based cohort study.

SETTING

Population of Denmark from 1 January 2000 to 31 December 2022.

PARTICIPANTS

3.5 million individuals (51.7% women and 48.3% men) who did not have atrial fibrillation at 45 years of age or older were followed up until incident atrial fibrillation, migration, death, or end of follow-up, whichever came first. All 362 721 individuals with incident atrial fibrillation (46.4% women and 53.6% men), but with no prevalent complication, were further followed up until incident heart failure, stroke, or myocardial infarction.

MAIN OUTCOME MEASURES

Lifetime risk of atrial fibrillation and lifetime risks of complications after atrial fibrillation over two prespecified periods (2000-10 v 2011-22).

RESULTS

The lifetime risk of atrial fibrillation increased from 24.2% in 2000-10 to 30.9% in 2011-22 (difference 6.7% (95% confidence interval 6.5% to 6.8%)). After atrial fibrillation, the most frequent complication was heart failure with a lifetime risk of 42.9% in 2000-10 and 42.1% in 2011-22 (-0.8% (-3.8% to 2.2%)). Individuals with atrial fibrillation lost 14.4 years with no heart failure. The lifetime risks of stroke and of myocardial infarction after atrial fibrillation decreased slightly between the two periods, from 22.4% to 19.9% for stroke (-2.5% (-4.2% to -0.7%)) and from 13.7% to 9.8% for myocardial infarction (-3.9% (-5.3% to -2.4%). No evidence was reported of a differential decrease between men and women.

CONCLUSION

Lifetime risk of atrial fibrillation increased over two decades of follow-up. In individuals with atrial fibrillation, about two in five developed heart failure and one in five had a stroke over their remaining lifetime after atrial fibrillation diagnosis, with no or only small improvement over time. Stroke risks and heart failure prevention strategies are needed for people with atrial fibrillation.

AF-React study: Prevalence of thrombotic events in patients with atrial fibrillation receiving NOACs - real-world data analysis from northern Portugal primary healthcare

Introduction

Anticoagulation is recommended for stroke prevention in patients with atrial fibrillation (AF). The guidelines suggest non-vitamin K antagonist anticoagulants (NOACs) as the primary therapy for anticoagulation in AF. Several patient-related factors increase the risk of thrombotic events: elderly individuals, a previous history of stroke, and chronic kidney disease. This study aims to determine the association between NOACs and other patient variables in AF and the occurrence of thrombotic events.

Methods

The database included all adults with the code K78 (ICPC-2 code for AF) who received clinical care in Northern Portugal's Primary Health Care between January 2016 and December 2018 and were dispensed the same NOAC at the pharmacy.

Results

The results indicate that 10.2% of AF patients on NOAC anticoagulation experienced a stroke. Furthermore, patients treated with apixaban and dabigatran had higher odds of experiencing a stroke compared to those treated with rivaroxaban. Among patients with the same age, gender, and CHA2DS2Vasc Score, apixaban was significantly associated with a higher likelihood of thrombotic events than rivaroxaban.

Discussion

These results have not been previously reported in studies with real-world data; therefore, a more detailed analysis should be conducted to enhance the validity of these findings.

Stroke and bleeding risk in atrial fibrillation with CHA2DS2-VASC risk score of one: the Norwegian AFNOR study

BACKGROUND AND AIMS

The benefit of oral anticoagulant (OAC) therapy in atrial fibrillation (AF) and intermediate stroke risk is debated. In a nationwide Norwegian cohort with a non-sex CHA2DS2-VASc risk score of one, this study aimed to investigate (i) stroke and bleeding risk in AF patients with and without OAC treatment, and (ii) the risk of stroke in non-anticoagulated individuals with and without AF.

METHODS

A total of 1 118 762 individuals including 34 460 AF patients were followed during 2011-18 until ischaemic stroke, intracranial haemorrhage, increased CHA2DS2-VASc score, or study end. One-year incidence rates (IRs) were calculated as events per 100 person-years (%/py). Cox regression models provided adjusted hazard ratios (aHRs [95% confidence intervals]).

RESULTS

Among AF patients, the ischaemic stroke IR was 0.51%/py in OAC users and 1.05%/py in non-users (aHR 0.47 [0.37-0.59]). Intracranial haemorrhage IR was 0.28%/py in OAC users and 0.19%/py in non-users (aHR 1.23 [0.88-1.72]). Oral anticoagulant use was associated with an increased risk of major bleeding (aHR 1.37 [1.16-1.63]) but lower risk of the combined outcome of ischaemic stroke, major bleeding, and mortality (aHR 0.57 [0.51-0.63]). Non-anticoagulated individuals with AF had higher risk of ischaemic stroke compared to non-AF individuals with the same risk profile (aHR 2.47 [2.17-2.81]).

CONCLUSIONS

In AF patients at intermediate risk of stroke, OAC use was associated with overall favourable clinical outcomes. Non-anticoagulated AF patients had higher risk of ischaemic stroke compared to the general population without AF with the same risk profile.

Screening for atrial fibrillation to prevent stroke in elderly individuals with or without preexisting cardiovascular disease: A post hoc analysis of the randomized LOOP Study

BACKGROUND

An evidence-based approach for risk stratification of subclinical atrial fibrillation (AF) and hereby AF screening is lacking. This study aimed to investigate whether established cardiovascular diseases (CVD) could help to identify the population more likely to benefit from AF screening.

METHODS

The LOOP Study randomized AF-naïve individuals aged ≥70 years and with additional stroke risk factors to either screening with implantable loop recorder (ILR) and subsequent anticoagulation upon detection of new-onset AF episodes ≥6 min, or usual care. In this sub-study, all participants were divided into two risk groups according to the presence/absence of CVD (defined as ischemic heart disease, heart failure, previous stroke, valvular heart disease, or peripheral artery disease).

RESULTS

A total of 1997 (33.3%) had CVD at baseline and experienced higher incidences of stroke or systemic arterial embolism (SAE), ischemic stroke, stroke/SAE/cardiovascular death, and all-cause death (adjusted HR 1.34 [1.06-1.69], 1.31 [1.02-1.69], 1.49 [1.23-1.79], and 1.59 [1.36-1.85], respectively) than those without. For ILR screening versus usual care, there was no decrease in stroke/SAE, ischemic stroke, or stroke/SAE/cardiovascular death among participants with CVD (adjusted p-values >0.05), whereas significant reductions in these outcomes were obtained by screening among those without CVD (adjusted HR 0.64 [0.44-0.93], 0.54 [0.35-0.82], 0.64 [0.46-0.87], respectively); adjusted p-values for interaction ≤0.05.

CONCLUSIONS

In an elderly, at-risk population, ILR screening did not prevent stroke significantly in individuals with CVD, whereas screening was associated with approximately 40% stroke risk reduction among those without CVD. However, these findings should be considered as hypothesis-generating and warrant further study.

Risk Factors and Risk Model Construction of Stroke in Patients with Vertigo in Emergency Department

Objective

We aimed to explore the risk factors of stroke in patients with vertigo in the emergency department and establish a risk prediction model for stroke patients.

Methods

A total of 301 patients experiencing vertigo in our hospital from January 2020 to January 2021 were retrospectively included. Patients were divided into the stroke group (n = 56) and the nonstroke group (n = 245). The clinical characteristics of patients in both groups were collected and compared, followed by binary logistic regression that was employed to determine the risk factors that affect stroke diagnosis. The receiver operating characteristic (ROC) curve was used to clarify the effectiveness of the constructed model.

Results

Patients in the stroke group were older and had higher systolic and diastolic blood pressure on admission than the nonstroke group. Meanwhile, they demonstrated a higher proportion of diabetes and atrial fibrillation and focal muscle weakness, dysarthria, dysphagia, or ataxia in neurological examinations compared to the nonstroke group (all P < 0.05). The proportion of patients in the nonstroke group who had a history of vertigo or inner ear disease was significantly higher than that in the stroke group (P < 0.05). The patient's age ≥ 60 years old (OR = 3.57), diabetes (OR = 4.57), atrial fibrillation (OR = 4.26), previous history of vertigo or inner ear disease (OR = 0.16), focal muscle weakness (OR = 4.34), and dysphagia or ataxia (OR = 4.08) were associated with a higher risk of stroke. The area under the curve for stroke was 0.87, and the sensitivity and specificity were 98.2% and 57.6%, respectively, as the sum of the assigned scores was greater than 3.

Conclusions

Age ≥ 60 years old, diabetes, atrial fibrillation, previous history of vertigo or inner ear disease, focal muscle weakness, dysphagia, or ataxia were associated with a higher risk of stroke. The risk model constructed based on our findings may help to assess the risk of stroke in patients with vertigo in the emergency department.

Universal Clinician Device for improving risk prediction and management of patients with atrial fibrillation: an assumed benefit analysis

Aim

Atrial fibrillation (AF) management guidelines advise using risk tools to optimize AF treatment. This study aims to develop a dynamic and clinically applicable digital device to assess stroke and bleeding risk, and to facilitate outcome improvements in AF patients. The device will provide tailored treatment recommendations according to easily attainable individual patient data.

Methods and Results

This Universal Clinician Device (UCD) was created using the GARFIELD-AF registry using a split sample approach. The GARFIELD-AF risk tool was adapted with two modifications. First, predictors with ≥1000 missing data points were separated, allowing expected risks estimation. Second, recommendations for modifiable risk factors and associated 2-year outcome estimates were incorporated. Outcomes of interest were all-cause mortality, non-haemorrhagic stroke/systemic embolism (SE), and major bleeding. All patients were randomized to a derivation (n = 34853) and validation cohort (n = 17165). In the derivation cohort, predictors were identified using least absolute shrinkage and selection operator regression. Cox models were fitted with the selected parameters. The UCD demonstrated superior predictive power compared with CHA₂DS₂VASc for all-cause mortality [0.75(0.75-0.76) vs. 0.71(0.70-0.72)] and non-haemorrhagic stroke/SE [0.68(0.66-0.70) vs. 0.65(0.63-0.67)], and with HAS-BLED for major bleeding [0.69(0.67-0.71) vs. 0.64(0.62-0.65)]. Universal Clinician Device recommendations reduced all-cause mortality (8.45-5.42%) and non-haemorrhagic stroke/SE (2.58-1.50%). Patients with concomitant diabetes and chronic kidney disease benefitted further, reducing mortality risk from 13.15% to 8.67%. One-third of patients with a CHA₂DS₂VASc score of >1 had the lowest risk of stroke.

Conclusion

The UCD simultaneously predicts mortality, stroke, and bleeding risk in patients using easily attainable individual clinical data and guideline-based optimized treatment plans.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier for GARFIELD-AF: NCT01090362.

Decision aids for shared decision-making and appropriate anticoagulation therapy in patients with atrial fibrillation: a systematic review and meta-analysis

AIMS

Underuse of oral anticoagulants (OACs) is commonly observed among patients with atrial fibrillation (AF), which hinders stroke prevention in AF. Shared decision-making (SDM) can help enhance adherence by minimizing patients' misunderstanding of treatment and aligning care with their preferences. Decision aids (DAs) have been developed to facilitate the SDM process. This study aimed to: (i) evaluate the effects of DAs on AF patients' knowledge, decisional conflict, OAC uptake, and adherence and on the incidence of stroke and bleeding; and (ii) explore characterizing factors associated with enhanced DA effectiveness.

METHODS AND RESULTS

Five databases were searched. Meta-analysis was conducted using RevMan 5.3 when data were available. Comparative analysis between effective and ineffective DAs was conducted to determine the DA designs associated with better effects. Ten studies were included. Pooling results indicated that DAs reduce decisional conflict related to warfarin use [mean difference = -0.10; 95% confidence interval (CI): -0.18 to -0.02; P = 0.01] and enhance OAC uptake [risk ratio: 1.03; 95% CI: 1.01-1.05; P = 0.004]. The effects of DAs on adherence and incidence of stroke and bleeding were unclear. Comparative analysis revealed that DAs with key elements of SDM (situation diagnosis, choice awareness, option clarification, benefits and disadvantages, and patient's preference) and pre-consultation delivery are more likely to be effective in promoting SDM and OAC uptake.

CONCLUSIONS

DAs are promising in promoting SDM and OAC uptake in patients with AF. The evidence on adherence and incidence of stroke and bleeding remains uncertain. More trials with rigorous study design and longer follow-up are necessary to obtain evidence.

Evaluation of the Risk of Stroke Without Anticoagulation Therapy in Men and Women With Atrial Fibrillation Aged 66 to 74 Years Without Other CHA2DS2-VASc Factors

Importance

There are limited clinical trial data and discrepant recommendations regarding use of anticoagulation therapy in patients with atrial fibrillation (AF) aged 65 to 74 years without other stroke risk factors.

Objectives

To evaluate the risk of stroke without anticoagulation therapy in men and women with AF aged 66 to 74 years without other CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes, stroke, vascular disease, age 65-74 years, female sex) risk factors and examine the association of stroke incidence with patient age.

Design, Setting, and Participants

A population-based retrospective cohort study was conducted using linked administrative databases. The population included 16 351 individuals aged 66 to 74 years who were newly diagnosed with AF in Ontario, Canada, between April 1, 2007, and March 31, 2017. Exclusion criteria included long-term care residence, prior anticoagulation therapy, valvular disease, heart failure, hypertension, diabetes, stroke, and vascular disease. The cumulative incidence function was used to estimate the 1-year incidence of stroke in patients who did not receive anticoagulation therapy. Fine-Gray regression was used to study the association of patient characteristics with stroke incidence and derive estimates of stroke risk at each age. Death was treated as a competing risk and patients were censored if they initiated anticoagulation therapy. Inverse probability of censoring weights was used to account for patient censoring. Data analysis was performed from May 26, 2019, to December 9, 2020.

Exposures

Atrial fibrillation and age.

Main Outcomes and Measures

Hospitalizations for stroke.

Results

Of the 16 351 individuals with AF (median [interquartile range] age, 70 [68-72] years), 8352 (51.1%) were men; 6314 individuals (38.6%) started anticoagulation therapy during follow-up. The overall 1-year stroke incidence among patients who did not receive anticoagulation therapy was 1.1% (95% CI, 1.0%-1.3%) and the incidence of death without stroke was 8.1% (95% CI, 7.7%-8.5%). The incidence of stroke was not significantly associated with sex. The estimated 1-year stroke risk increased with patient age from 66 years (0.7%; 95% CI, 0.5%-0.9%) to 74 years (1.7%; 95% CI, 1.3%-2.1%).

Conclusions and Relevance

The risk of stroke more than doubled in this study as men and women with AF but no other CHA2DS2-VASc risk factors aged from 66 to 74 years. These data suggest that anticoagulation therapy is more likely to benefit older individuals within this group of patients, whereas younger individuals are less likely to gain net clinical benefit from anticoagulation therapy.

Sacubitril/Valsartan Decreases Atrial Fibrillation Susceptibility by Inhibiting Angiotensin II-Induced Atrial Fibrosis Through p-Smad2/3, p-JNK, and p-p38 Signaling Pathways

Sacubitril/valsartan (SAC/VAL) prevents angiotensin II (AngII) from binding AT1-R and blocks degradation of natriuretic peptides. Despite its efficacy in reducing ventricular fibrosis and preserving cardiac functions, which has been extensively demonstrated in myocardial infarction or pressure overload models, few studies have been conducted to determine whether SAC/VAL could attenuate atrial fibrosis and decrease atrial fibrillation (AF) susceptibility. Our study provided evidence for the inhibition of atrial fibrosis and reduced susceptibility to AF by SAC/VAL. After 28 days of AngII continuous subcutaneous stimulation, rats in SAC/VAL group exhibited reduced extent of atrial fibrosis, inhibited proliferation, migration, and differentiation of atrial fibroblasts, and decreased susceptibility to AF. We further found that inhibition of p-Smad2/3, p-JNK, and p-p38MAPK pathways is involved in the role of SAC/VAL on AngII-induced atrial fibrosis in vivo. These results emphasize the importance of SAC/VAL in the prevention of AngII-induced atrial fibrosis and may help to enrich the options for AF pharmacotherapy.

Modelling tool to support decision-making in the NHS Health Check programme: workshops, systematic review and co-production with users

BACKGROUND

Local authorities in England commission the NHS Health Check programme to invite everyone aged 40-74 years without pre-existing conditions for risk assessment and eventual intervention, if needed. However, the programme's effectiveness, cost-effectiveness and equity impact remain uncertain.

AIM

To develop a validated open-access flexible web-based model that enables local commissioners to quantify the cost-effectiveness and potential for equitable population health gain of the NHS Health Check programme.

OBJECTIVES

The objectives were as follows: (1) co-produce with stakeholders the desirable features of the user-friendly model; (2) update the evidence base to support model and scenario development; (3) further develop our computational model to allow for developments and changes to the NHS Health Check programme and the diseases it addresses; (4) assess the effectiveness, cost-effectiveness and equity of alternative strategies for implementation to illustrate the use of the tool; and (5) propose a sustainability and implementation plan to deploy our user-friendly computational model at the local level.

DESIGN

Co-production workshops surveying the best-performing local authorities and a systematic literature review of strategies to increase uptake of screening programmes informed model use and development. We then co-produced the workHORSE (working Health Outcomes Research Simulation Environment) model to estimate the health, economic and equity impact of different NHS Health Check programme implementations, using illustrative-use cases.

SETTING

Local authorities in England.

PARTICIPANTS

Stakeholders from local authorities, Public Health England, the NHS, the British Heart Foundation, academia and other organisations participated in the workshops. For the local authorities survey, we invited 16 of the best-performing local authorities in England.

INTERVENTIONS

The user interface allows users to vary key parameters that represent programme activities (i.e. invitation, uptake, prescriptions and referrals). Scenarios can be compared with each other.

MAIN OUTCOME MEASURES

Disease cases and case-years prevented or postponed, incremental cost-effectiveness ratios, net monetary benefit and change in slope index of inequality.

RESULTS

The survey of best-performing local authorities revealed a diversity of effective approaches to maximise the coverage and uptake of NHS Health Check programme, with no distinct 'best buy'. The umbrella literature review identified a range of effective single interventions. However, these generally need to be combined to maximally improve uptake and health gains. A validated dynamic, stochastic microsimulation model, built on robust epidemiology, enabled service options analysis. Analyses of three contrasting illustrative cases estimated the health, economic and equity impact of optimising the Health Checks, and the added value of obtaining detailed local data. Optimising the programme in Liverpool can become cost-effective and equitable, but simply changing the invitation method will require other programme changes to improve its performance. Detailed data inputs can benefit local analysis.

LIMITATIONS

Although the approach is extremely flexible, it is complex and requires substantial amounts of data, alongside expertise to both maintain and run.

CONCLUSIONS

Our project showed that the workHORSE model could be used to estimate the health, economic and equity impact comprehensively at local authority level. It has the potential for further development as a commissioning tool and to stimulate broader discussions on the role of these tools in real-world decision-making.

FUTURE WORK

Future work should focus on improving user interactions with the model, modelling simulation standards, and adapting workHORSE for evaluation, design and implementation support.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42019132087.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 35. See the NIHR Journals Library website for further project information.

Impact of atrial fibrillation on the risk of ischemic stroke in patients on hemodialysis: BOREAS-HD3 Study

BACKGROUND

Atrial fibrillation (AF) is an established risk factor for ischemic stroke in a general population. However, its impact in patients on hemodialysis (HD), a group with a high risk for stroke, is still controversial. Here we examined this issue in a Japanese cohort.

METHODS

This study was designed as a multicenter cohort study. HD patients (n = 1,067) were enrolled from 22 institutes in January 2009 and followed up for 3 years. Patients with missing data (n = 196) or kidney transplantation (n = 4) were excluded, and 867 patients contributed to the analysis of the risk of new-onset of ischemic stroke.

RESULTS

At baseline, AF was observed in 123 patients (14.2%, AF group) and not in the others (n = 744: 85.8%, non-AF group). During a follow-up period of 31.3 months, the cumulative incidence rate for ischemic stroke was significantly higher in the AF group than in the non-AF group (6.5% vs. 2.9%, p < 0.05). In Cox regression analysis, AF was a significant independent risk factor for new-onset of ischemic stroke after adjustment for age, sex, prior history of ischemic stroke, use of warfarin, dialysis vintage, comorbidity of diabetic nephropathy, and interdialytic weight gain (hazard ratio 2.17-2.68).

CONCLUSION

Present analyses using comprehensive adjustment for multiple confounders, including prior history of ischemic stroke, indicated that AF independently increases the risk of new-onset of ischemic stroke by more than twofold in Japanese HD patients.

A Novel Model for Prediction of Thromboembolic and Cardiovascular Events in Patients Without Atrial Fibrillation

Patients without atrial fibrillation (AF) constitute approximately 75% of patients suffering thromboembolism and major adverse cardiovascular events (MACE), but evidence supporting risk stratification in these patients is sparse. We aimed to develop a risk prediction model for identification of patients without AF at high risk of first-time thromboembolic events. We included 72,381 coronary angiography patients without AF and without previous ischemic stroke or transient ischemic attack. The cohort was randomly divided into a derivation cohort (80%, n = 57,680) and a validation cohort (20%, n = 14,701). The primary thromboembolic end point was a composite of ischemic stroke, transient ischemic attack, and systemic embolism. MACE was defined as a composite of cardiac death, myocardial infarction, and ischemic stroke. The final model was compared with 2 validated clinical risk models (CHADS₂ and CHA₂DS₂-VASc). The risk prediction model assigned 1 point to heart failure, hypertension, diabetes mellitus, renal disease, age 65 to 74 years, active smoking, and multivessel obstructive coronary artery disease, and 2 points to age ≥75 years and peripheral artery disease. A C-index of 0.66 (95% CI 0.64 to 0.69) for prediction of the composite thromboembolic end point was found in the validation cohort, which was higher than for CHADS₂ (C-index 0.63 [95% CI 0.60 to 0.67]; p < 0.001) and CHA₂DS₂-VASc (C-index 0.64 [95% CI 0.62 to 0.67]; p = 0.034). The model also predicted MACE (C-index 0.71 [95% CI 0.69 to 0.73]). In conclusion it is possible to identify patients without AF at high risk of first-time thromboembolic events and MACE by use of a simple clinical prediction model.

Paroxysmal Atrial Fibrillation: An Independent Risk Factor for Prothrombotic Conditions

Objective

It remains unclear whether atrial fibrillation (AF) alone determines systemic changes in hemocoagulation. Our aim was to examine the prothrombin fragment F1+2 and fibrinopeptide A (FPA) as early markers of coagulation activity still in the first twenty-four hours of paroxysmal AF (PAF) and to correlate them with the arrhythmia onset.

Methods

51 non-anticoagulated patients (26 men, 25 women, aged 59.84±1.6 years) and 52 controls (26 men, 26 women, aged 59.50±1.46 years) were sequentially selected. F1+2 and FPA plasma levels were measured by enzyme-linked immunoassays.

Results

F1+2 was significantly higher in patients (292.61pmol/L±14.03pmol/L vs 183.40pmol/L±8.38pmol/L; p<0.001). FPA was also substantially higher (4.47ng/mL±0.25 ng/mL vs 3.09ng/mL±0.15ng/mL, p<0.001). Among the potential predictors for these deviations: age, gender, BMI, PAF duration and CHA₂DS₂-VASc score, it was established that higher F1+2 and FPA plasma levels were independently associated only with PAF duration (p<0.05). Moreover, longer episodes were associated with higher values of F1+2 (Adjusted R2 = 0.68) and FPA (Adjusted R2 = 0.70).

Conclusions

Increased coagulation activity was present still in the first twenty-four hours of PAF clinical presentation. The disease itself was associated with increasing hypercoagulability over time, suggesting its importance as an independent risk factor for thromboembolic events.

Self-reported risk of stroke and factors associated with underestimation of stroke risk among older adults with atrial fibrillation: the SAGE-AF study

BACKGROUND

Though engaging patients with atrial fibrillation (AF) in understanding their stroke risk is encouraged by guidelines, little is known regarding AF patients' perceived stroke risk or its relationship with oral anticoagulation (OAC) use. We aim to identify factors associated with underestimation of stroke risk among older patients with AF and relate this to OAC use.

METHODS

Data are from the ongoing SAGE (Systematic Assessment of Geriatric Elements)-AF study, which included older patients (> 65 years) with non-valvular AF and a CHA₂DS₂-VASc score of ≥ 2. Participants reported their perceived risk of having a stroke without OAC. We compared the perceived risk to CHA₂DS₂-VASc predicted stroke risk and classified participants as "over" or "under" estimators, and identified factors associated with underestimation of risk using multiple logistic regression.

RESULTS

The average CHA₂DS₂-VASc score of 915 participants (average age: 75 years, 47% female, 86% white) was 4.3 ± 1.6, 43% of participants had discordant predicted and self-reported stroke risks. Among the 376 participants at highest risk (CHA₂DS₂-VASc score ≥ 5), 46% of participants underestimated their risk. Older participants (≥ 85 years) were more likely and OAC treated patients less likely to underestimate their risk of developing a future stroke than respective comparison groups.

CONCLUSIONS

A significant proportion of study participants misperceived their stroke risk, mostly by overestimating. Almost half of participants at high risk of stroke underestimated their risk, with older patients more likely to do so. Patients on OAC were less likely to underestimate their risk, suggesting that successful efforts to educate patients about their stroke risk may influence treatment choices.

Assessing absolute stroke risk in patients with atrial fibrillation using a risk factor-based approach

AIM

To assess the risk of stroke and thromboembolism in patients with atrial fibrillation (AF) based on risk factor combinations of the CHA2DS2-VASc score.

METHODS AND RESULTS

Using nationwide Danish registries, patients with AF were included from 1997 to 2015 in this retrospective observational study. A multiple logistic regression, including interactions of history of stroke with age at AF, calendar year of AF, and the CHA2DS2-VASc score risk factors (congestive heart failure, hypertension, diabetes, vascular disease, and female sex) were used to predict the personalized risks of stroke within 1 year. A total of 147 842 patients with AF were included in the study cohort (median age 76 years, range 20-100 years, 51% females). Within the first year, 6% of the cohort were diagnosed with stroke. The predicted personalized 1-year absolute risk of stroke varied widely within each CHA2DS2-VASc score. To estimate the personalized risk of stroke an online calculator was created, the Calculator of Absolute Stroke Risk (CARS), which allows calculation of all the possible combinations of the CHA2DS2-VASc score (https://hjerteforeningen.shinyapps.io/riskvisrr/).

CONCLUSION

Calculation of the individual risk using a risk factor-based approach as opposed to using average risk for a particular CHA2DS2-VASc score can improve risk estimates. Furthermore, CARS can assist in the communication of the stroke risk for a more evidence-based shared decision-making of whether to initiate oral anticoagulation therapy.

Incidence of Ischemic Stroke in Individuals With and Without Aortic Valve Stenosis: A Danish Retrospective Cohort Study

Background and Purpose- Aortic valve stenosis may lead to atrial and ventricular remodeling, predisposes to atrial fibrillation, and may also be an independent risk factor of ischemic stroke. However, information on stroke rates among persons with aortic valve stenosis are sparse. We aimed to determine the incidence rates and relative risks of ischemic stroke in individuals with diagnosed aortic valve stenosis compared with age- and sex-matched controls. Methods- All patients with incident aortic valve stenosis aged >18 years (n=79 310) and age- and sex-matched controls were identified using the Danish nationwide registries (1997-2017). Incidence rates per 1000 person-years (PY) and multivariable adjusted hazard ratios with 95% CIs were reported. Results- In total, 873 373 individuals (median age 77 years, 51.5% men, 9.1% with aortic valve stenosis) were included. Ischemic stroke occurred in 70 205 (8.0%) individuals during 4 880 862 PY of follow-up. Incidence rates of ischemic stroke were 13.3/1000 PY among the controls compared with 30.4/1000 PY in patients with aortic valve stenosis, corresponding to a hazard ratio of 1.31 (95% CI, 1.28-1.34). In all age-groups, the incidence rates and relative risks were significantly increased in patients with aortic valve stenosis compared with controls, but the relative risk was greater for younger individuals (eg, age group, 18-45 years: hazard ratio, 5.94 [95% CI, 4.10-8.36]). In patients with aortic valve stenosis above 65 years of age, the risk of ischemic stroke was markedly lower after aortic valve replacement (30.3 versus 19.6/1000 PY before and after valve replacement). Among people with atrial fibrillation the incidence rate of ischemic stroke was 1.5 times higher when aortic valve stenosis was present (33.0/1000 PY versus 49.9/1000 PY). Conclusions- People with aortic valve stenosis have a significantly increased risk of ischemic stroke compared with age- and sex-matched controls. Future studies are warranted to explore whether antithrombotic therapy may be beneficial in some individuals.

Left Atrial Volume as a Biomarker of Atrial Fibrillation at Routine Chest CT: Deep Learning Approach

Purpose

To test the performance of a deep learning (DL) model in predicting atrial fibrillation (AF) at routine nongated chest CT.

Materials and Methods

A retrospective derivation cohort (mean age, 64 years; 51% female) consisting of 500 consecutive patients who underwent routine chest CT served as the training set for a DL model that was used to measure left atrial volume. The model was then used to measure atrial size for a separate 500-patient validation cohort (mean age, 61 years; 46% female), in which the AF status was determined by performing a chart review. The performance of automated atrial size as a predictor of AF was evaluated by using a receiver operating characteristic analysis.

Results

There was good agreement between manual and model-generated segmentation maps by all measures of overlap and surface distance (mean Dice = 0.87, intersection over union = 0.77, Hausdorff distance = 4.36 mm, average symmetric surface distance = 0.96 mm), and agreement was slightly but significantly greater than that between human observers (mean Dice = 0.85 [automated] vs 0.84 [manual]; P = .004). Atrial volume was a good predictor of AF in the validation cohort (area under the receiver operating characteristic curve = 0.768) and was an independent predictor of AF, with an age-adjusted relative risk of 2.9.

Conclusion

Left atrial volume is an independent predictor of the AF status as measured at routine nongated chest CT. Deep learning is a suitable tool for automated measurement.© RSNA, 2019See also the commentary by de Roos and Tao in this issue.

Relationship between hemoglobin A1c and serum troponin in patients with diabetes and cardiovascular events

OBJECTIVES

Diabetes mellitus is a group of metabolic disorders associated with high risk for cardiovascular disease. Although troponins are primarily clinically used for the diagnosis of acute coronary syndrome, they are also used in risk assessment in patients with acute coronary syndrome as well as in a number of other conditions. The aim of this review was to investigate the relationship between hemoglobin A1c and serum troponin in patients with diabetes and cardiovascular events.

METHODS

Hemoglobin A1c has been chosen as the best clinical indicator of glucose control and risk of micro and macrovascular complications. We investigated cardiac troponins as a group of markers of muscle injury which includes troponin T, troponin I and troponin C. Troponin T and I are specific for myocardial injury, compared to C which is specific for skeletal muscle.

RESULTS

In this review, we showed that there was a causal relation between hemoglobin A1c levels and serum troponin concentrations. Hemoglobin A1c has shown to be a positive predictive factor of incidence, mortality and morbidity of conditions such as acute coronary syndrome, arrhythmias, stroke, pulmonary embolism and other conditions that causes troponin elevation by its release in circulation.

CONCLUSIONS

Chronic hyperglycemia decreases glomerular filtration and consequently decreases troponin elimination and also by affecting the heart microcirculation it leads to microvascular damage and consequently to ischemia which contribute to troponin concentration elevation. Furthermore, correlation between hemoglobin A1c and troponin concentration manifests in their prognostic value for mortality.

Ambient Air Pollution and the Risk of Atrial Fibrillation and Stroke: A Population-Based Cohort Study

BACKGROUND

Although growing evidence links air pollution to stroke incidence, less is known about the effect of air pollution on atrial fibrillation (AF), an important risk factor for stroke.

OBJECTIVES

We assessed the associations between air pollution and incidence of AF and stroke. We also sought to characterize the shape of pollutant-disease relationships.

METHODS

The population-based cohort comprised 5,071,956 Ontario residents, age 35–85 y and without the diagnoses of both outcomes on 1 April 2001 and was followed up until 31 March 2015. AF and stroke cases were ascertained using health administrative databases with validated algorithms. Based on annual residential postal codes, we assigned 5-y running average concentrations of fine particulate matter ([Formula: see text]), nitrogen dioxide ([Formula: see text]), and ozone ([Formula: see text]) from satellite-derived data, a land-use regression model, and a fusion-based method, respectively, as well as redox-weighted averages of [Formula: see text] and [Formula: see text] ([Formula: see text]) for each year. Using Cox proportional hazards models, we estimated the hazard ratios (HRs) and 95% confidence intervals (95% CIs) of AF and stroke with each of these pollutants, adjusting for individual- and neighborhood-level variables. We used newly developed nonlinear risk models to characterize the shape of pollutant–disease relationships.

RESULTS

Between 2001 and 2015, we identified 313,157 incident cases of AF and 122,545 cases of stroke. Interquartile range increments of [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] were associated with increases in the incidence of AF [HRs (95% CIs): 1.03 (1.01, 1.04), 1.02 (1.01, 1.03), 1.01 (1.00, 1.02), and 1.01 (1.01, 1.02), respectively] and the incidence of stroke [HRs (95% CIs): 1.05 (1.03, 1.07), 1.04 (1.01, 1.06), 1.05 (1.03, 1.06), and 1.05 (1.04, 1.06), respectively]. Associations of similar magnitude were found in various sensitivity analyses. Furthermore, we found a near-linear association for stroke with [Formula: see text], whereas [Formula: see text], [Formula: see text]-, and [Formula: see text] relationships exhibited sublinear shapes.

CONCLUSIONS

Air pollution was associated with stroke and AF onset, even at very low concentrations. https://doi.org/10.1289/EHP4883.

Predicting stroke in patients without atrial fibrillation

BACKGROUND

Only few studies in selected cohorts have examined whether the CHA₂ DS₂ -VASc score can predict the risk of atrial fibrillation and thromboembolic events in patients without atrial fibrillation.

MATERIALS AND METHODS

Patients with coronary angiography performed between 2004 and 2012 were grouped according to CHA₂ DS₂ -VASc score. We excluded patients with atrial fibrillation, anticoagulant therapy and follow-up <30 days. The endpoints were atrial fibrillation and a composite of ischaemic stroke, transient ischaemic attack and systemic embolism. Event rates per 100 person-years were estimated for each CHA₂ DS₂ -VASc score (0, 1, 2, 3, 4, and >4). Incidence rate ratios were calculated using low-risk patients (CHA₂ DS₂ -VASc score 0 in males or 1 in females) as reference.

RESULTS

In total, 78 233 patients were included with group sizes varying between 8299 (CHA₂ DS₂ -VASc >4) and 19 882 (CHA₂ DS₂ -VASc 2). An increasing CHA₂ DS₂ -VASc score was significantly associated with a future diagnosis of atrial fibrillation (P for trend <0.0001) and an incremental risk of ischaemic stroke, transient ischaemic attack, systemic embolism (P for trend <0.0001) and all-cause death (P for trend <0.0001). Patients with a CHA₂ DS₂ -VASc score of 3 had a rate of ischaemic stroke/transient ischaemic attack/systemic embolism of 1.30 per 100 person-years.

CONCLUSIONS

Among patients undergoing coronary angiography, the CHA₂ DS₂ -VASc score predicted a future diagnosis of atrial fibrillation and the composite risk of ischaemic stroke, transient ischaemic attack or systemic embolism in patients without atrial fibrillation. A CHA₂ DS₂ -VASc score of 3 was associated with a risk that would justify prophylactic oral anticoagulation treatment in a patient with atrial fibrillation.

Stroke risk stratification in atrial fibrillation: a review of common risk factors

Atrial Fibrillation (AF) has become a major global health concern being the most common sustained arrhythmia in clinical practice. Risk factors for AF include congestive heart failure, hypertension, increasing age and diabetes. Many of these factors also increase the risk for thromboembolism and ischemic stroke in AF patients. Great efforts have been made from the latter part of the 20th century towards developing an ideal stroke risk stratification tool in AF with the aim of reducing the incidence of stroke in AF patients and the limiting unnecessary use of thromboprophylaxis. The thromboembolic risks posed by AF with valvular heart disease are an important subgroup that contributes to a significant proportion of stroke in AF patients globally. We review the evolution of stroke risk stratification and summarize the guidelines for stroke prevention in non-valvular AF as well as AF with valvular heart disease, and the most recent recommendations on stroke prevention in AF patients. Abbreviations: AF: Atrial Fibrillation; ACS: Acute Coronary Syndrome; CAD: Coronary Artery Disease; CCF: Congestive Cardiac Failure; DM: Diabetes Mellitus; EHRA: Evaluated Heartvalves, Rheumatic or Artificial; ICH: Intracranial Hemorrhage; NOACs: Novel Oral Anticoagulants; OAC: Oral Anticoagulants; PAD: Peripheral Arterial Disease ; TIA: Transient Ischemic Attack; VHD: Valvular Heart Disease.

Circulating proteomic patterns in AF related left atrial remodeling indicate involvement of coagulation and complement cascade

BACKGROUND

Left atrial (LA) electro-anatomical remodeling and diameter increase in atrial fibrillation (AF) indicates disease progression and is associated with poor therapeutic success. Furthermore, AF leads to a hypercoagulable state, which in turn promotes the development of a substrate for AF and disease progression in the experimental setting. The aim of this study was to identify pathways associated with LA remodeling in AF patients using untargeted proteomics approach.

METHODS

Peripheral blood samples of 48 patients (62±10 years, 63% males, 59% persistent AF) undergoing AF catheter ablation were collected before ablation. 23 patients with left atrial low voltage areas (LVA), defined as <0.5 mV, and 25 patients without LVA were matched for age, gender and CHA2DS2-VASc score. Untargeted proteome analysis was performed using LC-ESI-Tandem mass spectrometry in a label free intensity based workflow. Significantly different abundant proteins were identified and used for pathway analysis and protein-protein interaction analysis.

RESULTS

Analysis covered 280 non-redundant circulating plasma proteins. The presence of LVA correlated with 30 differentially abundant proteins of coagulation and complement cascade (q<0.05).

CONCLUSIONS

This pilot proteomic study identified plasma protein candidates associated with electro-anatomical remodeling in AF and pointed towards an imbalance in coagulation and complement pathway, tissue remodeling and inflammation.

Impact of atrial fibrillation on the rate of mild cognitive impairment in the elderly

Mild cognitive impairment (MCI) in patients with cardiovascular risks is a transitional state to vascular dementia but which still has a possibility of being managed. The objectives of this study were to assess the impact of atrial fibrillation (AF) on cognitive performances in the elderly in comparison with similar cardiovascular risks. One hundred unselected patients were included in AF+ and AF- groups. Patients with prodromal Alzheimer disease as shown by semantic cueing test, and those suffering from major cognitive decline according to DSM 5 criteria were evaluated separately from those patients analysed for vascular cognitive impairment. MCI was distinguished with the help of the Montreal cognitive assessment and the mood status was studied with the geriatric depression scale. AF+ patients predominantly had paroxysmal type of AF with a mean duration of 6.3 years, with 77% of the patients being on anticoagulation. AF- patients had arterial hypertension. Prevalence of MCI was significantly higher among AF- patients, possibly due to lower rates of BP control. These study results show less impact of AF itself on cognitive performances in comparison with uncontrolled hypertension.

Risk of stroke and transient ischaemic attack in patients with a diagnosis of resolved atrial fibrillation: retrospective cohort studies

OBJECTIVES

To determine rates of stroke or transient ischaemic attack (TIA) and all cause mortality in patients with a diagnosis of "resolved" atrial fibrillation compared to patients with unresolved atrial fibrillation and without atrial fibrillation.

DESIGN

Two retrospective cohort studies.

SETTING

General practices contributing to The Health Improvement Network, 1 January 2000 to 15 May 2016.

PARTICIPANTS

Adults aged 18 years or more with no previous stroke or TIA: 11 159 with resolved atrial fibrillation, 15 059 controls with atrial fibrillation, and 22 266 controls without atrial fibrillation.

MAIN OUTCOME MEASURES

Primary outcome was incidence of stroke or TIA. Secondary outcome was all cause mortality.

RESULTS

Adjusted incidence rate ratios for stroke or TIA in patients with resolved atrial fibrillation were 0.76 (95% confidence interval 0.67 to 0.85, P<0.001) versus controls with atrial fibrillation and 1.63 (1.46 to 1.83, P<0.001) versus controls without atrial fibrillation. Adjusted incidence rate ratios for mortality in patients with resolved atrial fibrillation were 0.60 (0.56 to 0.65, P<0.001) versus controls with atrial fibrillation and 1.13 (1.06 to 1.21, P<0.001) versus controls without atrial fibrillation. When patients with resolved atrial fibrillation and documented recurrent atrial fibrillation were excluded the adjusted incidence rate ratio for stroke or TIA was 1.45 (1.26 to 1.67, P<0.001) versus controls without atrial fibrillation.

CONCLUSION

Patients with resolved atrial fibrillation remain at higher risk of stroke or TIA than patients without atrial fibrillation. The risk is increased even in those in whom recurrent atrial fibrillation is not documented. Guidelines should be updated to advocate continued use of anticoagulants in patients with resolved atrial fibrillation.

Clinical profile and outcomes in octogenarians with atrial fibrillation: A community-based study in a specific European health care area

BACKGROUND

Age increases risk of stroke and bleeding. Clinical trial data have had relatively low proportions of elderly subjects. We sought to study a Spanish population of octogenarians with atrial fibrillation (AF) by combining different sources of electronic clinical records from an area where all medical centres utilized electronic health record systems.

METHODS

Data was derived from the Galician Healthcare Service information system.

RESULTS

From 383,000 subjects, AF was coded in 7990 (2.08%), 3640 (45.6%) of whom were ≥80 and 4350 (54.4%)<80. All CHA2DS2-VASc's components were more prevalent in the elderly except for diabetes. Of those ≥80, 2178 (59.8%) were women. Mean CHA₂DS₂-VASc was 4.2±1.1. Distribution of CHA₂DS₂-VASc components varied between genders. 2600 (71.4%) were on oral anticoagulant (OA). During a median follow up of 696days (124.23), all-cause mortality was higher in ≥80 (1011/3640 (27.8%) vs 350/4350 (8.05%) (p<0.001). There were differences in rate of thromboembolic (TE) and haemorrhagic events (2.3% vs 0.9%, p<0.01 and 2.5% vs 1.7%, p=0.01 respectively). In octogenarian, differences between genders were observed with regard to TE, but not in haemorrhagic or all-cause mortality rates. Age, heart failure, non-valvular AF, dementia, and OA were independent predictors of all-cause mortality. In regard to TE, female gender, hypertension, previous TE and OA were independent predictive factors.

CONCLUSIONS

Octogenarians with AF had very different characteristics and outcomes from their younger counterparts. These results also provide reassurance about the effectiveness of OA in preventing TE events and maintaining a reasonable haemorrhagic event rate in the extremely elderly.

Established and potential echocardiographic markers of embolism and their therapeutic implications in patients with ischemic stroke

Cardiogenic strokes comprised 11% of all strokes and 25% of ischemic strokes. An accurate identification of the cause of stroke is necessary in order to prepare an adequate preventive strategy. In this review the confirmed and potential causes of embolic strokes are presented, which can be detected in echocardiography in the context of present treatment guidelines and gaps in evidence. There remains a need for further studies assessing the meaning of potential cardiac sources of embolism and establishment of rules for optimal medical prevention (antiplatelet therapy [APT] vs. oral anticoagulation [OAC]) and interventional procedures to reduce the incidence of ischemic strokes. Currently available data does not provide definitive evidence on the comparative benefits of OAC vs. APT in patients with cryptogenic stroke or embolic stroke of undetermined source. There is a lack of antithrombotic treatment scheme in the time between stroke and the completed diagnosis of potential sources of thromboembolism.

Atrial Fibrillation and Cause-Specific Risks of Pulmonary Embolism and Ischemic Stroke

Background

Atrial fibrillation (AF) is a well‐established risk factor for ischemic stroke (IS). Emerging evidence also indicates an association between AF and pulmonary embolism (PE). Because IS may potentially mediate the observed risk of PE in AF, we aimed to assess the impact of AF on the cause‐specific risks of PE and IS in a large cohort recruited from the general population.

Methods and Results

We observed 29 842 participants from 3 surveys of the Tromsø study (inclusion in 1994–1995, 2001–2002, and 2007–2008) to the end of 2012. Incident events of AF, IS, and PE during follow‐up were recorded, and information on potential confounders was obtained at baseline. Cox regression models, with AF as a time‐dependent variable, were used to calculate cause‐specific hazard ratios (HRs) with 95% confidence intervals (CIs) for PE and IS. There were 2067 participants diagnosed as having AF, 296 with PE and 1164 with IS, during a median of 17.6 years of follow‐up. The risks of PE (HR, 10.88; 95% CI, 6.23–18.89) and IS (HR, 6.16; 95% CI, 4.47–8.48) were substantially increased during the first 6 months after AF diagnosis, with crude incidence rates of 18.5 per 1000 person‐years for PE and 52.8 per 1000 person‐years for IS. The risk estimates remained elevated for both PE (HR, 1.72; 95% CI, 1.10–2.71) and IS (HR, 2.45; 95% CI, 2.05–2.92) throughout the study period.

Conclusions

AF was associated with increased cause‐specific risks of both PE and IS. Our findings infer that the risk of PE in AF is not explained by intermediate IS.

Management of Complications in Anticoagulated Patients with Atrial Fibrillation

Oral anticoagulation is mandatory for patients at high risk of thromboembolism, but the risk of bleeding should also be taken into account. Direct oral anticoagulants are now recommended for non-valvular AF as a potential alternative to warfarin. In this article we discuss methods to assess the anticoagulant effect of these agents, specific and general antidotes, and management of complications such as embolic and haemorrhagic stroke, and significant bleeding.

Genetic Interactions with Age, Sex, Body Mass Index, and Hypertension in Relation to Atrial Fibrillation: The AFGen Consortium

It is unclear whether genetic markers interact with risk factors to influence atrial fibrillation (AF) risk. We performed genome-wide interaction analyses between genetic variants and age, sex, hypertension, and body mass index in the AFGen Consortium. Study-specific results were combined using meta-analysis (88,383 individuals of European descent, including 7,292 with AF). Variants with nominal interaction associations in the discovery analysis were tested for association in four independent studies (131,441 individuals, including 5,722 with AF). In the discovery analysis, the AF risk associated with the minor rs6817105 allele (at the PITX2 locus) was greater among subjects ≤ 65 years of age than among those > 65 years (interaction p-value = 4.0 × 10⁻⁵). The interaction p-value exceeded genome-wide significance in combined discovery and replication analyses (interaction p-value = 1.7 × 10⁻⁸). We observed one genome-wide significant interaction with body mass index and several suggestive interactions with age, sex, and body mass index in the discovery analysis. However, none was replicated in the independent sample. Our findings suggest that the pathogenesis of AF may differ according to age in individuals of European descent, but we did not observe evidence of statistically significant genetic interactions with sex, body mass index, or hypertension on AF risk.

Use of direct oral anticoagulants in patients with nonvalvular atrial fibrillation according to clinical profile

The majority of patients with atrial fibrillation should receive oral anticoagulation to reduce the risk of stroke. The limitations of vitamin K antagonists have led to an underuse of anticoagulants in clinical practice which has been associated with a higher risk of stroke, hospitalizations and healthcare costs. Direct oral anticoagulants (DOACs) overcome some of the limitations of vitamin K antagonists and may therefore increase the use of oral anticoagulants in clinical practice. Since no head-to-head trials have been performed, only indirect comparisons can be made among them. In this review, the results of the Phase III randomized controlled trials with DOACs were analyzed, trying to determine whether one or more DOACs could be especially recommended according to different clinical conditions.