Long-term Thromboembolic Risk in Patients With Postoperative Atrial Fibrillation After Coronary Artery Bypass Graft Surgery and Patients With Nonvalvular Atrial Fibrillation

Importance

New-onset postoperative atrial fibrillation (POAF) is a common complication of coronary artery bypass graft (CABG) surgery. However, the long-term risk of thromboembolism in patients who develop POAF after CABG surgery remains unknown. In addition, information on stroke prophylaxis in this setting is lacking.

Objective

To examine stroke prophylaxis and the long-term risk of thromboembolism in patients with new-onset POAF after first-time isolated CABG surgery compared with patients with nonsurgical, nonvalvular atrial fibrillation (NVAF).

Design, Setting, and Participants

This cohort study used data from a clinical cardiac surgery database and Danish nationwide registries to identify patients undergoing first-time isolated CABG surgery who developed new-onset POAF from January 1, 2000, through June 30, 2015. These patients were matched by age, sex, CHA2DS2-VASc score, and year of diagnosis to patients with nonsurgical NVAF in a 1 to 4 ratio. Data analysis was completed from February 2017 to January 2018.

Main Outcomes and Measures

The proportion of patients initiating oral anticoagulation therapy within 30 days and the rates of thromboembolism.

Results

A total of 2108 patients who developed POAF after CABG surgery were matched with 8432 patients with NVAF. In the full population of 10 540 patients, the median (interquartile range) age was 69.2 (63.7-74.7) years; 8675 patients (82.3%) were men. Oral anticoagulation therapy was initiated within 30 days postdischarge in 175 patients with POAF (8.4%) and 3549 patients with NVAF (42.9%). The risk of thromboembolism was lower in the POAF group than in the NVAF group (18.3 vs 29.7 events per 1000 person-years; adjusted hazard ratio [HR], 0.67; 95% CI, 0.55-0.81; P < .001). Anticoagulation therapy during follow-up was associated with a lower risk of thromboembolic events in both patients with POAF (adjusted HR, 0.55; 95% CI, 0.32-0.95; P = .03) and NVAF (adjusted HR, 0.59; 95% CI, 0.51-0.68; P < .001) compared with patients who did not receive any anticoagulation therapy. Further, the risk of thromboembolism was not significantly higher in patients with POAF compared with those who did not develop POAF after CABG surgery (adjusted HR, 1.11; 95% CI, 0.94-1.32; P < .24).

Conclusions and Relevance

New-onset POAF in patients who had undergone CABG surgery was associated with a lower long-term thromboembolic risk than that of patients who had NVAF. These data do not support the notion that new-onset POAF should be regarded as equivalent to primary NVAF in terms of long-term thromboembolic risk.

Utilization of oral anticoagulants in Korean nonvalvular atrial fibrillation patients

Background Although the majority of clinical guidelines indicate the use of NOAC (nonvitamin K antagonist oral anticoagulant) over vitamin K antagonist in nonvalvular atrial fibrillation patients, there is no information on real-world prescription factors that lead to a specific type of oral anticoagulant selection. Objective To evaluate the prescription factors for choosing a specific oral anticoagulant for nonvalvular atrial fibrillation patients in Korea. Setting Nationwide sampled database in South Korea. Methods In this study, we defined nonvalvular atrial fibrillation patients as having one or more hospitalizations or two or more out-patient visits with a stroke risk score (CHA2DS2-VASc scores) ≥ 2 eligible for oral anticoagulant therapy from Jan 1st, 2016 to Dec 31st, 2016. Baseline characteristics were analyzed, including sex, age, comorbidities, CHA2DS2-VASc, bleeding risk score (mHAS-BLED), prescribing specialty, insurance type, medical institution type and location. Univariate and multivariate logistic regression analyses were conducted for being prescribed NOAC compared with vitamin K antagonist. Main outcome measure Adjusted odds ratio of the NOAC group and vitamin K antagonist group. Results Of 9,226 patients eligible for oral anticoagulant therapy, 4999 patients (54.2%) received oral anticoagulant therapy, and 4517 patients took NOAC or vitamin K antagonist only during the study period. Prior stroke, transient ischemic attack, thromboembolism, thyroid disease, dyslipidemia, cancer, mHAS-BLED ≥ 5, in-patient care, and specialty in internal medicine and neurology were positive predictors of NOAC use over vitamin K antagonist, whereas young age (≤64), renal dysfunction, and secondary care institution were negative predictors of NOAC use over vitamin K antagonist. Conclusions The presence of comorbidities was linked to NOAC use over vitamin K antagonist, which is different from prescription factor studies in other countries and requires further study.

Subclinical and Asymptomatic Atrial Fibrillation: Current Evidence and Unsolved Questions in Clinical Practice

Atrial Fibrillation (AF) may be diagnosed due to symptoms, or it may be found as an incidental electrocardiogram (ECG) finding, or by implanted devices recordings in asymptomatic patients. While anticoagulation, according to individual risk profile, has proven definitely beneficial in terms of prognosis, rhythm control strategies only demonstrated consistent benefits in terms of quality of life. In fact, evidence collected by observational data showed significant benefits in terms of mortality, stroke incidence, and prevention of cognitive impairment for patients referred to AF catheter ablation compared to those medically treated, however randomized trials failed to confirm such results. The aims of this review are to summarize current evidence regarding the treatment specifically of subclinical and asymptomatic AF, to discuss potential benefits of rhythm control therapy, and to highlight unclear areas.

Atrial Fibrillation in Older People: Concepts and Controversies

Atrial fibrillation (AF) is the commonest cardiac rhythm abnormality and has a significant disease burden. Amongst its devastating complications is stroke, the risk of which increases with age. The stroke risk in an older person with AF is therefore tremendous, and oral-anticoagulation (OAC) therapy is central to minimizing this risk. The presence of age-associated factors such as frailty and multi-morbidities add complexity to OAC prescription decisions in older patients and often, OAC is needlessly withheld from them despite a lack of evidence to support this practice. Generally, this is driven by an over-estimation of the bleeding risk. This review article provides an overview of the concepts and controversies in managing AF in older people, with respect to the existing evidence and current practice. A literature search was conducted on Pubmed and Cochrane using keywords, and relevant articles published by the 1st of May 2019 were included. The article will shed light on common misconceptions that appear to serve as rationale for precluding OAC and focus on clinical considerations that may aid OAC prescription decisions where appropriate, to optimize AF management using an integrated, multi-disciplinary care approach. This is crucial for all patients, particularly older individuals who are most vulnerable to the deleterious consequences of this condition.

Impact of adding a video to patient education on quality of life among adults with atrial fibrillation: a randomized controlled trial

OBJECTIVE

To assess whether adding a video on atrial fibrillation (AF) to a face-to-face educational session improves quality of life (QoL), knowledge, and health resource utilization (HRU) among AF patients.

METHODS

In this parallel clinical trial, adults with AF received a face-to-face educational session on AF and were randomly allocated to watch an educational video or not. Self-reported questionnaires measured QoL (primary outcome; score 0-100), AF knowledge (score 0-25), and HRU. Data were collected before and after interventions. Within- and between-group changes were estimated by mixed models.

RESULTS

Sixty participants (age: 56 ± 13 years; men: n = 41) were allocated to watch the video after education (n = 30) or to receive education only (n = 30). Within groups over time, QoL and knowledge significantly improved. Knowledge increased by 2.3 units (95% confidence interval: 0.5-4.1) more in participants who watched the video than in others (P = 0.014). Changes in QoL and HRU were not different between groups.

CONCLUSION

Complementing education with a video on AF did not result in additional positive impacts on QoL and HRU among AF adults but led to greater improvements in AF knowledge.

PRACTICE IMPLICATIONS

The video on AF could be used as part of educational sessions to increase AF knowledge in AF patients.

GWAS contribution to atrial fibrillation and atrial fibrillation-related stroke: pathophysiological implications

Atrial fibrillation (AF) and stroke are included in a group of complex traits that have been approached regarding of their study by susceptibility genetic determinants. Since 2007, several genome-wide association studies (GWAS) aiming to identify genetic variants modulating AF risk have been conducted. Thus, 11 GWAS have identified 26 SNPs (p < 5 × 10^-2), of which 19 reached genome-wide significance (p < 5 × 10^-8). From those variants, seven were also associated with cardioembolic stroke and three reached genome-wide significance in stroke GWAS. These associations may shed a light on putative shared etiologic mechanisms between AF and cardioembolic stroke. Additionally, some of these identified variants have been incorporated in genetic risk scores in order to elucidate new approaches of stroke prediction, prevention and treatment.

Left Atrial Appendage Transcatheter Occlusion with AMPLATZER™ Amulet™ Device: Real Life Data with Mid-Term Follow-Up Results

Background

Left atrial appendage (LAA) occlusion is an alternative therapy for atrial fibrillation patients who have high embolic risk and contraindications to anticoagulant therapy.

Objective

To evaluate the feasibility, safety, and mid-term outcomes of percutaneous LAA occlusion, including device-related thrombosis.

Methods

Sixty consecutive patients who had undergone percutaneous LAA occlusion with AMPLATZER™ Amulet™ device from September 2015 to March 2018 were enrolled. Patients were followed for 21 ± 15 months (median - 20 months, interquartile range - 9 to 27 months). The postprocedural assessment was done at the 1^st, 6^th, and 12^th month. Patients were clinically evaluated, and transesophageal echocardiography was performed at each visit. We evaluated the condition of normality of variables using the Kolmogorov-Smirnov test. P-values < 0.05 were statistically significant.

Results

The most common indication for the procedure was major bleeding with anticoagulants (n: 53, 88.3%). The procedure was completed successfully in 59 (98.3%) patients. Periprocedural mortality was observed in one patient. Postprocedural antiplatelet treatment was planned as dual or single antiplatelet therapy or low-dose anticoagulant therapy in 52 (88.1%), 2 (3.4%), and 5 (8.5%) patients, respectively. We found no clinically significant cerebrovascular events, device-related thrombus, or embolization in any patient during the follow-up. Two (3.4 %) patients presented significant peri-device leak (>3 mm) at the 1^st month evaluation, which disappeared at the 12^th month follow-up.

Conclusion

We concluded that LAA occlusion using the Amulet™ LAA occluder can be performed with high procedural success and acceptable outcomes.

2019 EACTS Expert Consensus on long-term mechanical circulatory support

Long-term mechanical circulatory support (LT-MCS) is an important treatment modality for patients with severe heart failure. Different devices are available, and many-sometimes contradictory-observations regarding patient selection, surgical techniques, perioperative management and follow-up have been published. With the growing expertise in this field, the European Association for Cardio-Thoracic Surgery (EACTS) recognized a need for a structured multidisciplinary consensus about the approach to patients with LT-MCS. However, the evidence published so far is insufficient to allow for generation of meaningful guidelines complying with EACTS requirements. Instead, the EACTS presents an expert opinion in the LT-MCS field. This expert opinion addresses patient evaluation and preoperative optimization as well as management of cardiac and non-cardiac comorbidities. Further, extensive operative implantation techniques are summarized and evaluated by leading experts, depending on both patient characteristics and device selection. The faculty recognized that postoperative management is multidisciplinary and includes aspects of intensive care unit stay, rehabilitation, ambulatory care, myocardial recovery and end-of-life care and mirrored this fact in this paper. Additionally, the opinions of experts on diagnosis and management of adverse events including bleeding, cerebrovascular accidents and device malfunction are presented. In this expert consensus, the evidence for the complete management from patient selection to end-of-life care is carefully reviewed with the aim of guiding clinicians in optimizing management of patients considered for or supported by an LT-MCS device.

Indirect comparison of novel Oral anticoagulants among Asians with non-Valvular atrial fibrillation in the real world setting: a network meta-analysis

BACKGROUND

The development of novel oral anticoagulants (NOACs) has changed the landscape of non-valvular atrial fibrillation (NVAF) management. In this study, the effectiveness and the safety of several NOACs were evaluated in a real-world setting among Asian patients with NVAF.

METHODS

The literature search was conducted crossing different databases including Embase, MEDLINE, and the Cochrane Library from inception through March 1, 2019, for studies which included real-world perspectives comparing the individual NOACs with each other or with warfarin among Asians with NVAF. The primary outcomes were defined as stroke or systemic embolism (SSE) and major bleeding; ischemic stroke, all-cause death as well as intracranial bleeding were classified as the secondary outcomes.

RESULTS

From sixteen real-world studies, a total of 312,827 Asian patients were included in this analysis. In comparison with warfarin, the utilization of apixaban, dabigatran, and rivaroxaban significantly lowered the risk of major bleeding (apixaban: HR 0.47, 95%CI 0.35-0.63; dabigatran: HR 0.59, 95%CI 0.47-0.73; rivaroxaban: HR 0.66, 95%CI 0.52-0.83) and lessened the all-cause death rate (apixaban: HR 0.29, 95%CI 0.16-0.52; dabigatran: HR 0.40, 95%CI 0.27-0.60; rivaroxaban: HR 0.42, 95%CI 0.28-0.65). Apixaban (HR 0.59; 95%CI 0.40-0.85) reduced the possibility of ischemic stroke when compared against dabigatran. Rivaroxaban showed a higher chance of causing an ischemic stroke (HR 1.61; 95%CI 1.08-2.41) and major bleeding (HR 1.39; 95%CI 1.02-1.90) than Apixaban.

CONCLUSIONS

Apixaban, dabigatran and rivaroxaban were more effective than warfarin on reducing the risks of stroke and haemorrhage; meanwhile, apixaban was likely to lower the risk of major bleeding comparing to rivaroxaban.

TRIAL REGISTRATION

PROSPERO registry number: CRD42018086914 .

Additional cavotricuspid isthmus ablation may reduce recurrent atrial tachyarrhythmia after total thoracoscopic ablation for persistent atrial fibrillation

OBJECTIVES

Unlike catheter ablation, little is known about the benefits of cavotricuspid isthmus (CTI) ablation in total thoracoscopic ablation (TTA) of atrial fibrillation (AF). This study aimed to investigate the incidence of recurrent atrial tachyarrhythmia (ATa) according to additional CTI ablation after TTA in patients with persistent AF.

METHODS

Among 208 consecutive patients who underwent TTA for persistent AF at the Samsung Medical Center from February 2012 to January 2016, a total of 63 patients with CTI ablation and 91 patients without CTI ablation were included in the final analysis. CTI ablation was performed in patients who had long-standing AF or atrial flutter episodes during the admission period.

RESULTS

There was no difference in baseline characteristics between the CTI ablation and non-CTI ablation groups, except for a higher number of male patients in the CTI ablation group. The CTI ablation group showed a significantly higher survival rate free from recurrent ATa than that of the non-CTI ablation group at 5 years (52.5% vs 41.4%, P = 0.046). In the multivariable analysis, CTI ablation (hazard ratio 0.46, 95% confidence interval 0.217-0.971; P = 0.042) and left atrial volume index (hazard ratio 1.05, 95% confidence interval 1.029-1.070; P < 0.001) were significantly correlated with recurrent ATa.

CONCLUSIONS

Patients with CTI ablation showed a better survival rate free from recurrent ATa compared with the non-CTI ablation group. The additional CTI ablation may reduce recurrent ATa after TTA in patients with documented atrial flutter or long-standing AF.

A nurse-coordinated integrated care model to support decision-making and self-care in patients with atrial fibrillation: A study protocol

AIM

This study aims to evaluate the effects of a nurse-coordinated, empowerment-based integrated care model on self-care behaviours and psychosocial outcomes in patients with atrial fibrillation and to explore how this intervention affects patients' self-care behaviours and quality of life.

DESIGN

This mixed-methods study comprises a randomized controlled trial and an exploratory qualitative study.

METHODS

A total of 392 community-dwelling patients aged ≥65 years with a confirmed diagnosis of atrial fibrillation, a high stroke risk and no oral anticoagulants treatment will be recruited from the medical outpatient clinics of a university-affiliated hospital. The patients will be randomly allocated to intervention or control groups, which will receive treatment via the nurse-coordinated integrated care model or standard care, respectively. We hypothesize that compared with patients receiving standard care, atrial fibrillation patients exposed to the nurse-coordinated care model will be more likely to achieve compatible patient and physician decisions regarding the use of oral anticoagulants, better changes in medication adherence, anxiety, depression and health-related quality of life after the intervention. A subsample of 30 participants in the intervention group will also participate in a qualitative interview to provide their views and perceptions about the intervention. The ethical approval has obtained on 5 July 2018. This study is supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region on 29 June 2018.

DISCUSSION

This study will uniquely adopt an empowerment-based approach to equip patients as active agents in atrial fibrillation management through a nurse-coordinated integrated care model that comprehensively addresses their needs.

IMPACT

Patients with atrial fibrillation are currently receiving inadequate guideline-recommended care. This study will address this important evidence-practice gap by optimizing oral anticoagulant prescription and therapeutic effects and promotes effective patient self-care, so as to achieve worldwide reductions in atrial fibrillation-related morbidity, mortality, and healthcare burdens.

CLINICAL TRIAL REGISTRATION

This study has been registered at ClinicalTrials.gov (NCT03924739).

Stroke Risk in Atrial Fibrillation: Beyond the CHA2DS2-VASc Score

PURPOSE OF REVIEW

Stroke prevention is the cornerstone of atrial fibrillation (AF) management and the anticoagulation decision is currently based on CHA₂DS₂-VASc risk score. We discuss several novel risk factors besides those included in CHA₂DS₂-VASc score and alternative models for stroke prediction.

RECENT FINDINGS

Several clinical markers including obstructive sleep apnea and renal failure, laboratory markers like brain natriuretic peptide, imaging criteria including left atrial appendage morphology, spontaneous echo contrast, and coronary artery calcium score may predict stroke in AF patients. Addition of African American ethnicity to CHA₂DS₂-VASc score also improves stroke prediction in AF. Finally, novel models including TIMI-AF score, ATRIA score, and GARFIELD-AF scores have potential roles in risk stratification for stroke. While CHA₂DS₂-VASc score is the currently recommended risk stratification model for stroke prediction in AF, use of additional clinical, laboratory, imaging markers, ethnicity, and novel stroke prediction models may further assist in decision to anticoagulate the AF patient for stroke prevention.

Rate or Rhythm Control in Older Atrial Fibrillation Patients: Risk of Fall-Related Injuries and Syncope

OBJECTIVES

Management of atrial fibrillation (AF) with rate and/or rhythm control could lead to fall-related injuries and syncope, especially in the older AF population. We aimed to determine the association of rate and/or rhythm control with fall-related injuries and syncope in a real-world older AF cohort.

DESIGN

A retrospective cohort study.

SETTING

Danish nationwide administrative registries from 2000 to 2015.

PARTICIPANTS

A total of 100 935 patients with AF aged 65 years or older claiming prescription of rate-lowering drugs (RLDs) and/or anti-arrhythmic drugs (AADs) were included. We compared the use of rate-lowering monotherapy with rate-lowering dual therapy, AAD monotherapy, and AAD combined with rate-lowering therapy.

MEASUREMENTS

Outcomes were fall-related injuries and syncope as a composite end point (primary) or separate end point (secondary).

RESULTS

In this population, the median age was 78 years (interquartile range [IQR] = 72-84 y), and 53 481 (53.0%) were women. During a median follow-up of 2.1 years (IQR = 1.0-5.1), 17 132 (17.0%) experienced a fall-related injury, 5745 (5.7%) had a syncope, and 21 093 (20.9%) experienced either. Compared with rate-lowering monotherapy, AADs were associated with a higher risk of fall-related injuries and syncope. The incidence rate ratio (IRR) for the composite end point was 1.29 (95% confidence interval [CI]: 1.17-1.43) for AAD monotherapy and 1.46 [95% CI = 1.34-1.58] for AAD combined with rate-lowering therapy. When stratifying by individual drugs, amiodarone significantly increased the risk of fall-related injuries and syncope (IRR = 1.40 [1.26-1.55]). Compared with more than 180 days of rate-lowering monotherapy, a higher risk of all outcomes was seen in the first 90 days of any treatment; however, the greatest risk was in the first 14 days for those treated with AADs.

CONCLUSION

In AF patients aged 65 years and older, AAD use was associated with a higher risk of fall-related injuries and syncope, and the risk was highest within the first 14 days for those treated with AADs. Only amiodarone use was associated with a higher risk. J Am Geriatr Soc 67:2023-2030, 2019.

Arrhythmic Burden and Outcomes in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a devastating, life-limiting disease driven by small vessel vascular remodeling leading to a rise in pulmonary vascular resistance (PVR). Patients present with a range of symptoms including shortness of breath, exercise intolerance, palpitations or syncope. Symptoms may be related to vascular disease progression or arrhythmia secondary to the adaptation of the right heart to pressure overload. Arrhythmic burden is high in patients with left heart disease and guideline-based treatment of arrhythmias improves quality of life and prognosis. In PAH the incidence and prevalence of arrhythmias is less well-defined and there are no PAH-specific guidelines for arrhythmia management. We undertook a literature search identifying 13 relevant papers; detection of arrhythmias was acquired from 12-lead electrocardiogram (ECG) or Holter monitors. In all forms of pulmonary hypertension (PH) the prevalence of supraventricular arrhythmias (SVA) was 26-31%, ventricular arrhythmias (VA) 24% and a 5-year incidence of SVA ~13.2-25.1%. Prevalence and incidence of arrhythmias in PAH is less clear due to limited study numbers and the heterogenous nature of the patient population studied. For arrhythmia treatment, only single-arm studies of therapeutic strategies were reported using antiarrhythmic drugs (AAD), direct current cardioversion (DCCV) and ablation. Periods between ECG or Holter have not been investigated, highlighting the possibility that significant arrhythmias may be undetected. Advances in monitoring allow long-term surveillance via implanted/non-invasive monitors. Use of such technologies may provide an accurate estimate of incidence and prevalence of arrhythmias in patients with PAH, further defining relationships to adverse outcomes, and therapeutic options.

Non-Vitamin K Antagonist Oral Anticoagulants Versus Warfarin in Patients With Cancer and Atrial Fibrillation: A Systematic Review and Meta-Analysis

Background Several studies have investigated the effect of non-vitamin K antagonist oral anticoagulants (NOACs) in atrial fibrillation (AF) patients with cancer, but the results remain controversial. Therefore, we conducted a meta-analysis to compare the efficacy and safety of NOACs versus warfarin in this population. Methods and Results We systematically searched the PubMed and Embase databases until February 16, 2019 for studies comparing the effect of NOACs with warfarin in AF patients with cancer. Risk ratios (RRs) with 95% CIs were extracted and pooled by a random-effects model. Five studies involving 8908 NOACs and 12 440 warfarin users were included. There were no significant associations between cancer status and risks of stroke or systemic embolism, major bleeding, or death in AF patients. Compared with warfarin, NOACs were associated with decreased risks of stroke or systemic embolism (RR, 0.52; 95% CI, 0.28-0.99), venous thromboembolism (RR, 0.37, 95% CI, 0.22-0.63), and intracranial or gastrointestinal bleeding (RR, 0.65; 95% CI, 0.42-0.98) and with borderline significant reductions in ischemic stroke (RR, 0.63; 95% CI, 0.40-1.00) and major bleeding (RR, 0.73; 95% CI, 0.53-1.00). In addition, risks of efficacy and safety outcomes of NOACs versus warfarin were similar between AF patients with and without cancer. Conclusions In patients with AF and cancer, compared with warfarin, NOACs had lower or similar rates of thromboembolic and bleeding events and posed a reduced risk of venous thromboembolism.

The imminent epidemic of atrial fibrillation and its concomitant diseases - Myocardial infarction and heart failure - A cause for concern

Atrial fibrillation (AF) is increasingly common in the general population. It often coincides with myocardial infarction (MI) and heart failure (HF) which are also diseases in older adults. All three conditions share common cardiovascular risk factors. While hypertension and obesity are central risk factors for all three diseases, smoking and diabetes appear to have less impact on AF. To date, age is the single most important risk factor for AF in the general population. Further, epidemiological studies suggest a strong association of AF to MI and HF. The underlying pathophysiological mechanisms are complex and not fully understood. Both MI and HF can trigger development of AF, mainly by promoting structural and electrical atrial remodeling. On the other hand, AF facilitates HF and MI development via multiple mechanisms, resulting in a vicious circle of cardiac impairment and adverse cardiovascular prognosis. Consequently, to prevent and treat the coincidence of AF and HF or MI a strict optimization of cardiovascular risk factors is required.

Anticoagulation in Patients With Advanced Chronic Kidney Disease: Walking the Fine Line Between Benefit and Harm

Chronic kidney disease affects more than 3 million Canadians and is highly associated with cardiovascular diseases that require anticoagulation, such as atrial fibrillation and venous thromboembolism. Patients with chronic kidney disease are at a problematic crossroads; they are at high risk of thrombotic conditions requiring anticoagulation and bleeding complications due to anticoagulation. The limited high-quality clinical evidence to guide decision-making in this area further compounds the dilemma. In this review, we discuss the physiology and epidemiology of bleeding and thrombosis in patients with kidney disease. We specifically focus on patients with advanced kidney disease (estimated glomerular filtration rate ≤ 30 mL/min) or who are receiving dialysis and focus on the nephrologist perspective regarding these issues. We summarize the existing evidence for anticoagulation use in the prevention of stroke with atrial fibrillation and provide practical clinical recommendations for considering anticoagulation use in this population. Last, we examine specific scenarios such as the use of a glomerular filtration rate estimating equation and dosing, the use of existing prediction tools for stroke and hemorrhage risk, current patterns of anticoagulation use (including during the dialysis procedure), and vascular calcification with vitamin K antagonist use in patients with chronic kidney disease.

Deep learning for cardiovascular medicine: a practical primer

Deep learning (DL) is a branch of machine learning (ML) showing increasing promise in medicine, to assist in data classification, novel disease phenotyping and complex decision making. Deep learning is a form of ML typically implemented via multi-layered neural networks. Deep learning has accelerated by recent advances in computer hardware and algorithms and is increasingly applied in e-commerce, finance, and voice and image recognition to learn and classify complex datasets. The current medical literature shows both strengths and limitations of DL. Strengths of DL include its ability to automate medical image interpretation, enhance clinical decision-making, identify novel phenotypes, and select better treatment pathways in complex diseases. Deep learning may be well-suited to cardiovascular medicine in which haemodynamic and electrophysiological indices are increasingly captured on a continuous basis by wearable devices as well as image segmentation in cardiac imaging. However, DL also has significant weaknesses including difficulties in interpreting its models (the 'black-box' criticism), its need for extensive adjudicated ('labelled') data in training, lack of standardization in design, lack of data-efficiency in training, limited applicability to clinical trials, and other factors. Thus, the optimal clinical application of DL requires careful formulation of solvable problems, selection of most appropriate DL algorithms and data, and balanced interpretation of results. This review synthesizes the current state of DL for cardiovascular clinicians and investigators, and provides technical context to appreciate the promise, pitfalls, near-term challenges, and opportunities for this exciting new area.

Warfarin Use and Mortality, Stroke, and Bleeding Outcomes in a Cohort of Elderly Patients with non-Valvular Atrial Fibrillation

Aims

To determine exposure to warfarin and the associated outcomes in a population of older patients with non-valvular atrial fibrillation (NVAF).

Methods

Cohort study of patients aged 65-89 years admitted to hospital July 2003-December 2008 with newly-diagnosed or pre-existing AF. Outcomes at three years among one-year survivors post-index admission (landmark date) were all-cause mortality, stroke/systemic thromboembolism (stroke/TE) and bleeding. Multivariate Cox models were used to identify factors associated with each outcome.

Results

AF was the principal diagnosis for 27.5% of 17,336 index AF admissions. Of 14,634 (84.4%) patients alive at one-year 1,384 (9.5%) died in the following year. Vascular disease (42%) was the most frequent cause of death.Warfarin use, prior to the index admission and/or the 1-year landmark, did not exceed 40%.Compared to non-exposure or discontinuation at the index admission, initiation or persistence with warfarin prior to the landmark date was associated with reduced risk for all-cause mortality, a statistically non-significant reduction in risk for stroke/TE, and an increased risk for bleeding. Higher CHA2DS2-VASc scores were associated with increased risk for each outcome.

Conclusions

In a population-based cohort of hospitalised NVAF patients, the initiation and persistent use of warfarin was associated with lower all-cause mortality risk to three years, although reduction in risk for stroke/TE did not reach statistical significance. The apparent under-use of warfarin in this older, high-risk cohort reinforces the opportunity for further reduction in stroke/TE with the uptake of non-vitamin K oral anti-coagulants (NOACs) among those not prescribed, or not persistent with, warfarin.

Prevalence and Incidence of Atrial Fibrillation and Other Arrhythmias in the General Older Population: Findings From the Swedish National Study on Aging and Care

Aim: To study the prevalence and cumulative incidence of arrhythmias in the general population of adults aged 60 and older over a 6-year period. Study Design and Setting: Data were taken from the Swedish National Study on Aging and Care (SNAC), a national, longitudinal, multidisciplinary study of the general elderly population (defined as 60 years of age or older). A 12-lead resting electrocardiography (ECG) was performed at baseline and 6-year follow-up. Results: The baseline prevalence of atrial fibrillation (AF) was 4.9% (95% confidence interval [CI] = [4.5%, 5.5%]), and other arrhythmias including ventricular premature complexes (VPCs), supraventricular tachycardia (SVT), and supraventricular extrasystole (SVES) were seen in 8.4% (7.7%, 9.0%) of the population. A first- or second-degree atrioventricular (AV) block was found in 7.1% of the population (95% CI = [6.5%, 7.7%]), and there were no significant differences between men and women in baseline arrhythmia prevalence. The 6-year cumulative incidence of AF was 4.1% (95% CI = [3.5%, 4.9%]), or 6.9/1,000 person-years (py; 95% CI = [5.7, 8.0]). The incidence of AF, other arrhythmias, AV block, and pacemaker-induced rhythm was significantly higher in men in all cohorts except for the oldest. Conclusion: Our data highlight the prevalence and incidence of arrhythmias, which rapidly increase with advancing age in the general population.

A prospective observational survey on landiolol in atrial fibrillation/atrial flutter patients with chronic heart failure - AF-CHF landiolol survey

BACKGROUND

Atrial fibrillation and atrial flutter occur commonly in patients with heart failure. Ultrashort-acting β-blockers, including landiolol, can rapidly control heart rate. As part of postmarketing surveillance for landiolol in Japan, a real-world drug-use survey (AF-CHF landiolol survey) was established for the treatment of atrial fibrillation and atrial flutter in patients with heart failure. We report the safety and effectiveness of landiolol from this survey, focusing on adverse events/adverse drug reactions.

METHODS

Consecutive patients with cardiac dysfunction who received landiolol (continuous intravenous infusion, starting at 1μg/kg/min) for atrial fibrillation or atrial flutter in routine clinical practice in Japan were enrolled between June 2014 and May 2016. Safety variables included adverse events and adverse drug reactions (number of patients and events, incidence rate, types, seriousness). Effectiveness variables included the proportion of patients with a ≥20% decrease in heart rate.

RESULTS

Data were available for 1121 patients (safety analysis set); 888 patients were evaluable for effectiveness parameters. Mean (± standard deviation) patient age was 72.5±13.5 years, 57.2% were male. Most patients (84.2%) received landiolol for atrial fibrillation. Overall, 174 adverse events occurred in 140 patients (12.5%), including 105 serious adverse events. The most common type of adverse events was cardiac (60 events). Seventy-five events in 63 patients were categorized as adverse drug reactions (5.6% of patients). Mean heart rate decreased substantially after treatment with landiolol, by ≥20% in 77.5% of patients.

CONCLUSIONS

In a real-world setting in Japan, landiolol for the treatment of atrial fibrillation or atrial flutter with heart failure was acceptable without new safety concerns, and most patients achieved effective heart rate control during their arrhythmias.

Hybrid thoracoscopic surgical and transvenous catheter ablation versus transvenous catheter ablation in persistent and longstanding persistent atrial fibrillation (HARTCAP-AF): study protocol for a randomized trial

Background

Success rates with conventional transvenous endocardial pulmonary vein isolation in patients with persistent and longstanding persistent atrial fibrillation (AF) are variable due to advanced electrical and structural remodeling of the atria. As a consequence, more extensive endocardial lesions, minimally invasive thoracoscopic surgical techniques, and hybrid ablation (combining thoracoscopic epicardial surgical and endocardial catheter ablation) have been developed.

Hypothesis

The HARTCAP-AF trial hypothesizes that hybrid AF ablation is more effective than (repeated) transvenous endocardial catheter ablation in (longstanding) persistent AF, without increasing the number of associated major adverse events.

Methods

This randomized controlled trial will include 40 patients with persistent or longstanding persistent AF who will be 1:1 randomized to either hybrid ablation or (repeated) catheter ablation. The procedures and follow-up are conducted according to the guidelines. The primary effectiveness endpoint is freedom from any supraventricular arrhythmia lasting longer than 5 min without the use of Vaughan-Williams class I or III antiarrhythmic drugs through 12 months of follow-up after the last procedure. In the catheter ablation arm, a second procedure planned within 6 months after the index procedure is allowed for obtaining the primary endpoint. Additionally, adverse events, cost-effectiveness, and quality of life data will be recorded.

Trial registration

ClinicalTrials.gov, NCT02441738. Registered on 12 May 2015.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3365-9) contains supplementary material, which is available to authorized users.

Effect of catheter ablation on pre-existing abnormalities of left atrial systolic, diastolic, and neurohormonal functions in patients with chronic heart failure and atrial fibrillation

The critical role of the left atrium (LA) in cardiovascular homoeostasis is mediated by its reservoir, conduit, systolic, and neurohormonal functions. Atrial fibrillation is generally a reflection of underlying disease of the LA, especially in patients with heart failure. Disease-related LA remodelling leads to a decline in both atrial contractility and distensibility along with an impairment in the control of neurohormonal systems that regulate intravascular volume. Catheter ablation can lead to further injury to the atrial myocardium, as evidenced by post-procedural troponin release and tissue oedema. The cardiomyocyte loss leads to replacement fibrosis, which may affect up to 30-35% of the LA wall. These alterations further impair atrial force generation and neurohormonal functions; the additional loss of atrial distensibility can lead to a 'stiff LA syndrome', and the fibrotic response predisposes to recurrence of the atrial arrhythmia. Although it intends to restore LA systole, catheter ablation often decreases the chamber's transport functions. This is particularly likely in patients with long-standing atrial fibrillation and pre-existing LA fibrosis, especially those with increased epicardial adipose tissue (e.g. patients with obesity, diabetes and/or heart failure with a preserved ejection fraction). Although the fibrotic LA in these individuals is an ideal substrate for the development of atrial fibrillation, it may be a suboptimal substrate for catheter ablation. Such patients are not likely to experience long-term restoration of sinus rhythm, and catheter ablation has the potential to worsen their haemodynamic and clinical status. Further studies in this vulnerable group of patients are needed.

Individual and Combined Impact of Heart Failure and Atrial Fibrillation on Ischemic Stroke Outcomes

Background and Purpose- We aimed to determine individual and combined effects of atrial fibrillation (AF) and heart failure (HF) on acute ischemic stroke outcomes: in-hospital mortality, length-of-stay, and poststroke disability; long-term mortality and stroke recurrence. Methods- Prospective cohort study of patients with acute ischemic stroke admitted to a UK center with a catchment population of ≈900 000 between 2004 and 2016. Exposure groups were patients with neither AF nor HF (reference group), those with AF but without HF, those with HF but without AF, and those with AF+HF. Logistic and Cox regressions were used to model in-hospital and long-term outcomes, respectively. Results- A total of 10 816 patients with a mean age±SD =77.9±12.1 years, 48% male were included. Only 30 (4.9%) of the patients with HF but not AF were anticoagulated at discharge. Both AF (odds ratio, 1.24 [95% CI, 1.07-1.43]), HF (odds ratio, 1.40 [1.10-1.79]), and their combination (odds ratio, 2.23 [1.83-2.72]) were associated with increased odds of in-hospital mortality. All 3 exposure groups were associated with increased length-of-stay, while only AF predicted increased disability (1.36 [1.12-1.64]). Patients were followed for a median of 5.5 and 3.7 years for mortality and recurrence, respectively. Long-term mortality was associated with AF (hazard ratio, 1.45 [95% CI, 1.33-1.59]), HF (2.07 [1.83-2.36]), and their combination (2.20 [1.96-2.46]). Recurrent stroke was associated with AF 1.50 (1.26-1.78), HF (1.33 [1.01-1.75]), and AF with HF (1.62 [1.28-2.07]). Conclusions- The AF-associated excess risk of stroke recurrence was independent of comorbid HF. HF without AF was also associated with a significant risk of recurrence. Anticoagulation for secondary stroke prevention in patients with HF without AF may require further evaluation in a clinical trial setting.

Electrocardiographic RR Interval Dynamic Analysis to Identify Acute Stroke Patients at High Risk for Atrial Fibrillation Episodes During Stroke Unit Admission

Patients at short-term risk of paroxysmal atrial fibrillation (PAF) often exhibit increased RR interval variability during sinus rhythm. We studied if RR dynamic analysis, applied in the first hours after stroke unit (SU) admission, identified acute ischemic stroke patients at higher risk for subsequent PAF episodes detected within the SU hospitalization. Acute ischemic stroke patients underwent continuous cardiac monitoring (CCM) using standard bedside monitors immediately after SU admission. The CCM tracks from the first 48 h were analyzed using a telemedicine service (SRA clinic, Apoplex Medical, Germany). Based on the RR dynamics, the stroke risk analysis (SRA) algorithm stratified the risk for PAF as follows: low risk for PAF, high risk for PAF, presence of manifest AF. The subsequent presence/absence of PAF during the whole SU hospitalization was ruled out using all available CCMs, standard ECGs, or 24-h Holter ECGs. Two hundred patients (40% females, mean age 71 ± 16 years) were included. According to the initial SRA analysis, 111 patients (56%) were considered as low risk for PAF, 52 (26%) as high risk while 37 patients (18%) had manifest AF. A low-risk level SRA was associated with a reduced probability for subsequent PAF detection (1/111, 0.9%, 95% CI 0-4.3%) while a high-risk level SRA predicted an increased probability (20/52, 38.5% (95% CI 25-52%). RR dynamic analysis performed in the first hours after ischemic stroke may stratify patients into categories at low or high risk for forthcoming paroxysmal AF episodes detected within the SU hospitalization.

Practice Variation in Anticoagulation Prescription and Outcomes After Device-Detected Atrial Fibrillation

BACKGROUND

Device-detected atrial fibrillation (AF) is associated with increased risk of stroke; however, there are no clearly defined thresholds of AF burden at which to initiate oral anticoagulation (OAC). We sought to describe OAC prescription practice variation in response to new device-detected AF and the association with outcomes.

METHODS

We performed a retrospective cohort study using data from the Veterans Health Administration linked to remote monitoring data that included day-level AF burden. We included patients with cardiac implantable electronic devices and remote monitoring from 2011 to 2014, CHA2DS2-VASc score ≥2, and no prior stroke or OAC receipt in the preceding 2 years. We determined the proportion of patients prescribed OAC within 90 days after new device-detected AF across a range of AF thresholds (≥6 minutes to >24 hours) and examined site variation in OAC prescription. We used multivariable Cox proportional hazards regressions to determine the association of OAC prescription with stroke by device-detected AF burden.

RESULTS

Among 10 212 patients with cardiac implantable electronic devices, 4570 (45%), 3969 (39%), 3263 (32%), and 2469 (24%) had device-detected AF >6 minutes, >1 hour, >6 hours, and >24 hours, respectively. For device-detected AF >1 hour, 1712 patients met inclusion criteria (72±10 years; 1.5% female; CHA2DS2-VASc score 4.0±1.4; HAS-BLED score 2.6±1.1). The proportion receiving OAC varied based on device-detected AF burden (≥6 minutes: 272/2101 [13%]; >1 hour: 273/1712 [16%]; >6 hours: 263/1279 [21%]; >24 hours: 224/818 [27%]). Across 52 sites (N=1329 patients), there was substantial site-level variation in OAC prescription after device-detected AF >1 hour (median, 16%; range, 3%-67%; median odds ratio, 1.56 [95% credible interval, 1.49-1.71]). In adjusted models, OAC prescription after device-detected AF >24 hours was associated with reduced stroke risk (hazard ratio, 0.28; 95% CI, 0.10-0.81; P=0.02), although the propensity-adjusted model was significant when AF lasted at least 6 minutes.

CONCLUSIONS

Among veterans with cardiac implantable electronic devices, device-detected AF is common. There is large practice variation in 90-day OAC initiation after new device-detected AF, with low rates of treatment overall, even for episodes that last >24 hours. The strongest association of OAC with reduction in stroke was observed after device-detected AF >24 hours. Randomized trials are needed to confirm these observational findings.

Cerebrovascular events, bleeding complications and device related thrombi in atrial fibrillation patients with chronic kidney disease and left atrial appendage closure with the WATCHMAN™ device

BACKGROUND

Impaired renal function increases the bleeding risk, leading to a conservative prescription and frequent discontinuation of oral anticoagulation in atrial fibrillation patients with chronic kidney disease (CKD). Interventional left atrial appendage closure (LAAC) might be an alternative therapeutic strategy for these patients.

METHODS

We aimed to prospectively assess cerebrovascular (CE) and bleeding events, as well as peri-procedural and long-term complications in a cohort of consecutive patients undergoing interventional LAAC using the WATCHMAN™ device, with focus on CKD patients.

RESULTS

One hundred and eighty-nine consecutive patients undergoing interventional LAAC were included in this analysis; 171 (90.5%) patients had a reduced estimated glomerular filtration rate (eGFR; patients for each CKD stage: II = 66; IIIa = 32; IIIb = 43; IV = 18; V = 12). During a follow-up of 310 patient years three (1.0%) patients suffered a CE (two strokes, one transitory ischemic attack) and five (1.6%) other ones a bleeding complication. The observed stroke rate was more than two-thirds and the bleeding risk more than half lower than expected. Device related thrombi (DRT) were detected in twelve (6.5%) patients; women had significantly more DRT than men (12.5% vs. 2.6%; p = 0.009). Patients with an eGFR< 30 ml/min/1.73m2 showed a trend to a higher DRT rate as compared to the opposite group (13.3% vs. 5.1%; p = 0.10). Thrombus resolved with temporary oral anticoagulation therapy in ten patients without sequelae; thrombus consolidation was confirmed by serial TEE controls in the remaining two patients.

CONCLUSIONS

Atrial fibrillation patients with CKD have low CE and bleeding rates after LAAC with the WATCHMAN™ device. DRT risk is higher in female and patients with severe CKD. More frequent post-interventional TEE controls might be justified for early DRT detection and safe management of patients at high DRT risk.

TRIAL REGISTRATION

(German Clinical Trials Register ID: DRKS00 010768 ; Registration Date 07.07.2016).

Dabigatran dual therapy with ticagrelor or clopidogrel after percutaneous coronary intervention in atrial fibrillation patients with or without acute coronary syndrome: a subgroup analysis from the RE-DUAL PCI trial

AIMS

After percutaneous coronary intervention (PCI) in patients with atrial fibrillation, safety and efficacy with dabigatran dual therapy were evaluated in pre-specified subgroups of patients undergoing PCI due to acute coronary syndrome (ACS) or elective PCI, and those receiving ticagrelor or clopidogrel treatment.

METHODS AND RESULTS

In the RE-DUAL PCI trial, 2725 patients were randomized to dabigatran 110 mg or 150 mg with P2Y12 inhibitor, or warfarin with P2Y12 inhibitor and aspirin. Mean follow-up was 14 months, 50.5% had ACS, and 12% received ticagrelor. The risk of the primary endpoint, major or clinically relevant non-major bleeding event, was reduced with both dabigatran dual therapies vs. warfarin triple therapy in patients with ACS [hazard ratio (95% confidence interval), 0.47 (0.35-0.63) for 110 mg and 0.67 (0.50-0.90) for 150 mg]; elective PCI [0.57 (0.43-0.76) for 110 mg and 0.76 (0.56-1.03) for 150 mg]; receiving ticagrelor [0.46 (0.28-0.76) for 110 mg and 0.59 (0.34-1.04) for 150 mg]; or clopidogrel [0.51 (0.41-0.64) for 110 mg and 0.73 (0.58-0.91) for 150 mg], all interaction P-values >0.10. Overall, dabigatran dual therapy was comparable to warfarin triple therapy for the composite endpoint of death, myocardial infarction, stroke, systemic embolism, or unplanned revascularization, with minor variations across the subgroups, all interaction P-values >0.10.

CONCLUSION

The benefits of both dabigatran 110 mg and 150 mg dual therapy compared with warfarin triple therapy in reducing bleeding risks were consistent across subgroups of patients with or without ACS, and patients treated with ticagrelor or clopidogrel.

Prevention and Treatment of Acute Stroke in the Nonagenarians and Beyond: Medical and Ethical Issues

PURPOSE OF REVIEW

As one of the fastest growing portions of the population, nonagenarians will constitute a significant percentage of the stroke patient population in the near future. Nonagenarians are nevertheless not specifically targeted by most clinical guidelines. In this review, we aimed to summarise the available evidence guiding stroke prevention and treatment in this age group.

RECENT FINDINGS

Several recent observational studies have shown that the benefits of anticoagulation for the oldest old patients with atrial fibrillation may outweigh the bleeding risk. A sub-analysis of the IST-3 trial has shown for the first time that thrombolysis treatment in acute ischaemic stroke may be beneficial and safe even in octogenarian patients and older. Several recent observational studies have assessed thrombolysis in nonagenarians. The latest of these has shown better disability outcomes without increased rates of symptomatic intracerebral haemorrhage with thrombolysis. Nonagenarian stroke patients may benefit from similar preventative and therapeutic strategies as their younger counterparts. A few important exceptions include primary prevention using aspirin or statins. Patient selection is nevertheless essential given the increased adverse event rates. Patient preference should play a key role in the decision-making process. Clinical trials including more nonagenarian patients are required to yield more robust evidence.

The clinical outcomes of patients who developed typical atrial flutter on class 1C anti arrhythmic medications treated with hybrid approach

Introduction

A common approach to patients, who developed atrial flutter secondary to treatment with class 1C anti‐arrhythmic drugs for atrial fibrillation (AF) (1C flutter), is a hybrid approach: ablation of the Cavo‐Tricuspid isthmus (CTI) and continuation 1C medical treatment to prevent recurrence of AF. We aim to explore the clinical outcome of patients treated in this approach.

Methods and Results

Two hundred and four consecutive patients who underwent ablation for typical AFL at a tertiary medical center between 2010 and 2016 were enrolled and followed up. The clinical outcome of patient treated by the hybrid approach (treatment group; n = 67) was compared to patient without history of AF (control group; n = 137). The primary endpoint was time to occurrence of AF. Twenty‐eight (41.8%) patients in treatment group had AF occurrence in 1 year, including 9 (13.4%) patients who needed to escalate anti‐arrhythmic drug treatment to class III, and 11 (16.4%) patients who underwent AF ablation. In comparison, only 21 (15.3%) patients in control group had occurrence during the first year after ablation. The median time from ablations till AF occur was 106 ± 481 days in treatment group, and 403 ± 668 days in control group (P < .01).

Conclusions

There is a relatively high rate of AF recurrence in patients treated with the hybrid approach during the first year after CTI ablation. An alternative approach should be considered in this selected population.

Long-term outcomes of radiofrequency catheter ablation for atrial fibrillation in rheumatic heart disease patients with mild mitral stenosis

PURPOSE

To assess efficacy of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) in rheumatic heart disease (RHD) patients with mild mitral stenosis (MS).

METHODS

This retrospective cohort study included 62 consecutive RHD patients with mild MS and AF and 124 AF patients without RHD with matched age, gender, AF types as control. Procedure endpoints were defined as circumferential pulmonary vein ablation (CPVA) for paroxysmal AF, CPVA plus bidirectional block of lines, and disappearance of complex fractionated atrial electrograms for non-paroxysmal patients in both groups.

RESULTS

Cumulative success rate during the total follow-up (RHD, 23-140 months; control, 24-140 months) was lower in RHD group than control (32.3 vs. 56.5%, log-rank P = 0.006). In RHD patients, the success rate was higher in paroxysmal AF patients than non-paroxysmal AF patients during the mid-term follow-up (55.0 vs. 26.2%, log-rank P = 0.041), and was similar between the two AF types during the total follow-up (45.0 vs. 26.2%, log-rank P = 0.130). Patients without mitral regurgitation (MR) or with mild MR had a higher success rate than patients with moderate MR during the total follow-up in both groups (45.0 vs. 9.1%, log-rank P = 0.014 in RHD group; 64.5 vs. 43.8%, log-rank P = 0.001 in control group).

CONCLUSIONS

The long-term outcome of RFCA for AF in RHD patients with mild MS was mediocre and worse than that for AF patients without RHD. The severity of MR was associated with RFCA outcome in both groups. In RHD patients with mild MS, a better prognosis of paroxysmal AF than non-paroxysmal AF was observed initially but turned similar over time.

Invasive therapies for patients with concomitant heart failure and atrial fibrillation

Atrial fibrillation (AF) and heart failure (HF) are two clinical entities that can present either separately or concurrently. One entity can lead to the other and vice versa as AF can not only be the underlying etiology of HF but also exacerbate HF due to other cardiac diseases. Besides prevention of cerebral and systemic embolism and elimination of AF-related symptoms, restoration of sinus rhythm for AF patients helps to avoid or reduce HF, irrespective of their underlying heart disease. Successful rates of medical therapy for AF are low in persistent AF, and much lower in long-standing AF, while invasive procedures for AF yield promising results. In this review, the authors evaluate the value of invasive therapies for HF patients complicated with non-valvular AF. We examine this clinical problem by interpreting the relationships between these two entities: the mechanism of tachycardia-induced cardiomyopathy (TIC), past opinions about rhythm control and rate control of AF, discrimination of HF-related AF and AF-induced HF, how to identify the AF patients that could benefit from invasive therapies, and how to select invasive therapies for different AF patients and peri-operative treatments.

High-resolution Mapping in Patients with Persistent AF

Ablation of AF through electrical isolation of the pulmonary veins is a well-established technique and a cornerstone in the ablation of AF, although there are a variety of techniques and ablation strategies now available. However, high numbers of patients are returning to hospital after ablation procedures such as pulmonary vein isolation (PVI). Scar tissue (as identified by contact voltage mapping) is found to be present in many of these patients, especially those with persistent AF and even those with paroxysmal AF. This scarring is associated with poor outcomes after PVI. Cardiac mapping is necessary to locate triggers and substrate so that an ablation strategy can be optimised. Multipolar mapping catheters offer more information regarding the status of the tissue than standard ablation catheters. A patient-tailored catheter ablation approach, targeting the patient-specific low voltage/fibrotic substrate can lead to improved outcomes.

Stroke prevention in patients from Latin American countries with non-valvular atrial fibrillation: Insights from the GARFIELD-AF registry

BACKGROUND

Atrial fibrillation (AF) is an important preventable cause of stroke. Anticoagulation (AC) therapy can reduce this risk. However, prescribing patterns and outcomes in patients with non-valvular AF (NVAF) from Latin American countries are poorly described.

METHODS

Using data from the Global Anticoagulant Registry in the FIELD-AF (GARFIELD-AF), we examined the stroke prevention strategies and the 1-year outcomes in patients from four Latin American countries: Argentina, Brazil, Chile, and Mexico.

RESULTS

A total of 4162 patients (2010-2014) were included in this analysis. At the time of AF diagnosis, 39.9% of patients were prescribed vitamin K antagonists (VKA) ± antiplatelet (AP) therapy, 21.8% non-VKA oral anticoagulant (NOAC) ± AP, 24.1% AP only and 14.1% no antithrombotic treatment. The proportion of moderate-high risk patients receiving no AC therapy at participating centers was highest in Mexico (46.4%) and lowest in Chile (14.3%). During 1-year follow-up, the rates of all-cause mortality, stroke/SE and major bleeding were: 5.77 (95% CI) (5.06-6.56), 1.58 (1.23-2.02), and 0.99 (0.72-1.36) and per 100 person-years, respectively, which are higher than the global rates across all countries in GARFIELD-AF. Unadjusted rates of all-cause mortality were highest in Argentina, 6.95 (5.43-8.90), and lowest in Chile, 4.01 (2.92-5.52).

CONCLUSIONS

GARFIELD-AF results describes the marked variation in the baseline characteristics and patterns of antithrombotic treatments in patients with NVAF in four Latin American countries. Over one-third of patients with a moderate-to-high risk of stroke received no AC therapy, highlighting the need for improved management of patients according to national guideline. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362.

Utility of left atrial strain for predicting atrial fibrillation following ischemic stroke

Twenty-five percent of ischemic strokes (IS) are cryptogenic, but it is estimated that paroxysmal atrial fibrillation (PAF) is the underlying cause in up to a third of cases. We aimed to investigate the predictive value of speckle tracking of the left atrium (LA) in diagnosing PAF in IS patients. We retrospectively studied 186 IS patients with a clinical echocardiographic examination during sinus rhythm. Outcome was PAF defined by at least one reported episode of AF following their IS. Conventional echocardiographic measures were performed. Global longitudinal strain (GLS), LA reservoir-(ε_s), conduit-(ε_e), contraction-strain (ε_a) and LA dyssynchrony (standard deviation of time-to-peak ε_s; LA SD-T2P) were obtained by left ventricular and LA speckle tracking. Of 186 patients, 28 (15%) were diagnosed with PAF. PAF-patients did not differ from non-PAF patients with regards to GLS nor SD-TPS, but atrial strain measures were significantly impaired at baseline (ε_s 27 vs. 35%, ε_e 12 vs. 16%, ε_a 15 vs. 18%, p < 0.02 for all, for PAF and non-PAF, respectively). However, only ε_s remained independently associated with PAF after adjustment for clinical and echocardiographic parameters (OR 1.13 [1.04; 1.22], p = 0.003, per 1% decrease). ε_s also provided the highest area under the receiver operating characteristic curve among all variables (AUC = 0.74). With a cutoff of 29%, ε_s had a specificity of 76% and a negative predictive value of 93%. Atrial reservoir strain is independently associated with PAF and may be used to improve the diagnosis of PAF following IS.

New-Onset Atrial Fibrillation in Adult Patients After Cardiac Surgery

Purpose of Review

An overview of recent literature regarding pathophysiology, risk factors, prophylaxis, and treatment of new-onset atrial fibrillation (AF) in post-cardiac surgical patients.

Recent Findings

AF is the most frequent adverse event after cardiac surgery with significant associated morbidity, mortality, and financial cost. Its causes are multifactorial, and models to stratify patients into risk categories are progressing but a consistent, evidence-based system has not yet been developed. Pharmacologic and surgical interventions to prevent and treat this complication have been an area of ongoing research and recent societal guidelines reflect this.

Summary

Inconsistencies remain surrounding how to best identify higher-risk AF patients, which interventions should be used to prevent and treat AF, and which patient groups should receive these interventions. The evidence for these available strategies and their place in contemporary guidelines are summarized.

Body composition and atrial fibrillation: a Mendelian randomization study

AIMS

Increases in fat-free mass and fat mass have been associated with higher risk of atrial fibrillation (AF) in observational studies. It is not known whether these associations reflect independent causal processes. Our aim was to evaluate independent causal roles of fat-free mass and fat mass on AF.

METHODS AND RESULTS

We conducted a large observational study to estimate the associations between fat-free mass and fat mass on incident AF in the UK Biobank (N = 487 404, N events = 10 365). Genome-wide association analysis was performed to obtain genetic instruments for Mendelian randomization (MR). We evaluated the causal effects of fat-free mass and fat mass on AF with two-sample method by using genetic associations from AFGen consortium as outcome. Finally, we evaluated independent causal effects of fat-free mass and fat mass with multivariate MR. Both fat-free mass and fat mass had observational associations with incident AF [hazard ratio (HR) = 1.77, 95% confidence interval (CI) 1.72-1.83; HR = 1.40, 95% CI 1.37-1.43 per standard deviation increase in fat-free and fat mass, respectively]. The causal effects using the inverse-variance weighted method were 1.55 (95% CI 1.38-1.75) for fat-free mass and 1.30 (95% CI 1.17-1.45) for fat mass. Weighted median, Egger regression, and penalized methods showed similar estimates. The multivariate MR analysis suggested that the causal effects of fat-free and fat mass were independent of each other (causal risk ratios: 1.37, 95% CI 1.06-1.75; 1.28, 95% CI 1.03-1.58).

CONCLUSION

Genetically programmed increases in fat-free mass and fat mass independently cause an increased risk of AF.

Data-driven discovery and validation of circulating blood-based biomarkers associated with prevalent atrial fibrillation

AIMS

Undetected atrial fibrillation (AF) is a major health concern. Blood biomarkers associated with AF could simplify patient selection for screening and further inform ongoing research towards stratified prevention and treatment of AF.

METHODS AND RESULTS

Forty common cardiovascular biomarkers were quantified in 638 consecutive patients referred to hospital [mean ± standard deviation age 70 ± 12 years, 398 (62%) male, 294 (46%) with AF] with known AF or ≥2 CHA2DS2-VASc risk factors. Paroxysmal or silent AF was ruled out by 7-day ECG monitoring. Logistic regression with forward selection and machine learning algorithms were used to determine clinical risk factors, imaging parameters, and biomarkers associated with AF. Atrial fibrillation was significantly associated with age [bootstrapped odds ratio (OR) per year = 1.060, 95% confidence interval (1.04-1.10); P = 0.001], male sex [OR = 2.022 (1.28-3.56); P = 0.008], body mass index [BMI, OR per unit = 1.060 (1.02-1.12); P = 0.003], elevated brain natriuretic peptide [BNP, OR per fold change = 1.293 (1.11-1.63); P = 0.002], elevated fibroblast growth factor-23 [FGF-23, OR = 1.667 (1.36-2.34); P = 0.001], and reduced TNF-related apoptosis-induced ligand-receptor 2 [TRAIL-R2, OR = 0.242 (0.14-0.32); P = 0.001], but not other biomarkers. Biomarkers improved the prediction of AF compared with clinical risk factors alone (net reclassification improvement = 0.178; P < 0.001). Both logistic regression and machine learning predicted AF well during validation [area under the receiver-operator curve = 0.684 (0.62-0.75) and 0.697 (0.63-0.76), respectively].

CONCLUSION

Three simple clinical risk factors (age, sex, and BMI) and two biomarkers (elevated BNP and elevated FGF-23) identify patients with AF. Further research is warranted to elucidate FGF-23 dependent mechanisms of AF.

The cardiac isovolumetric contraction time is an independent predictor of incident atrial fibrillation and adverse outcomes following first atrial fibrillation event in the general population

Aims

Colour tissue Doppler imaging (TDI) M-mode through the mitral leaflet is an easy and precise method to obtain cardiac time intervals including the isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT), and ejection time (ET). The myocardial performance index (MPI) was defined as [(IVCT + IVRT)/ET]. Our aim was to investigate if cardiac time intervals can be used to predict atrial fibrillation (AF) in the general population.

Methods and results

A total of 1915 participants from the general population underwent a health examination including TDI echocardiography. The primary endpoint was AF, and the secondary endpoint was complicated AF as assessed by the occurrence of either stroke or heart failure (HF) after the diagnosis of AF. Participants with known AF were excluded (n = 54). During a median follow-up of 11 years, 166 participants (9%) were diagnosed with AF and of these 44 participants (27%) developed HF or stroke. Assessing the association between IVCT and incident AF, the risk increased with 27% per 10 ms increase in IVCT [per 10 ms increase: hazard ratio (HR) 1.27, 95% confidence interval (CI) (1.17–1.38); P &lt; 0.001]. The association remained significant after multivariable adjustment [per 10 ms increase: HR 1.22, 95% CI (1.09–1.35); P &lt; 0.001]. No associations between the IVRT, ET, MPI, and AF remained significant after multivariable adjustment. The IVCT also predicted complicated AF and the association remained significant even after multivariable adjustment [per 10 ms increase: HR 1.39, 95% CI (1.06–1.81); P = 0.015].

Conclusion

In the general population, the IVCT provides novel and independent prognostic information on the long-term risk of AF. Additionally, the IVCT can identify persons in risk of complicated AF.

Persistence on apixaban in atrial fibrillation patients: a retrospective multicentre study

AIMS

Real-world data on treatment persistence, safety and effectiveness of non-Vitamin K antagonist oral anticoagulants (NOACs) play an important role in the assessment of risks and benefits of these drugs. Our aim was to evaluate persistence on treatment, incidence of major bleeding and incidence of a composite endpoint of major events, including all-cause death, myocardial infarction, stroke and systemic thromboembolism, during treatment with apixaban in a cohort of patients with nonvalvular atrial fibrillation (NVAF).

METHODS

In this multicentre retrospective observational study, we retrieved data from medical records of five Italian hospitals on patients with a diagnosis of NVAF who initiated apixaban between 1 January 2014 and 31 March 2016 and had a first subsequent visit at the same hospital.

RESULTS

We studied 766 patients with mean age of 74.2 (standard deviation 11.1) years and median CHADS2 and CHA2DS2VASc scores of 2.0 and 4.0, respectively. Over a median follow-up period of 339 days, persistence on treatment was 83.5% [95% confidence interval (95% CI) 75.5-89.1%]. The rate of major bleeding (per 100 person-years) was 1.15 (95% CI 0.39-1.90 per 100 person-years), while the cumulative incidence was 4.4% (95% CI 1.6-12.0). The rate of major events was 1.97 (95% CI 1.08-2.86) per 100 patient-years, with a cumulative incidence over the entire follow-up period of 7.7% (95% CI 4.6-12.8).

CONCLUSION

In real-life conditions, NVAF patients treated with apixaban show rates of treatment discontinuation and major bleedings, which are comparable to those found in the ARISTOTLE pivotal study, thus supporting its external validity.

Mobile Phone-Based Use of the Photoplethysmography Technique to Detect Atrial Fibrillation in Primary Care: Diagnostic Accuracy Study of the FibriCheck App

Background

Mobile phone apps using photoplethysmography (PPG) technology through their built-in camera are becoming an attractive alternative for atrial fibrillation (AF) screening because of their low cost, convenience, and broad accessibility. However, some important questions concerning their diagnostic accuracy remain to be answered.

Objective

This study tested the diagnostic accuracy of the FibriCheck AF algorithm for the detection of AF on the basis of mobile phone PPG and single-lead electrocardiography (ECG) signals.

Methods

A convenience sample of patients aged 65 years and above, with or without a known history of AF, was recruited from 17 primary care facilities. Patients with an active pacemaker rhythm were excluded. A PPG signal was obtained with the rear camera of an iPhone 5S. Simultaneously, a single‑lead ECG was registered using a dermal patch with a wireless connection to the same mobile phone. PPG and single-lead ECG signals were analyzed using the FibriCheck AF algorithm. At the same time, a 12‑lead ECG was obtained and interpreted offline by independent cardiologists to determine the presence of AF.

Results

A total of 45.7% (102/223) subjects were having AF. PPG signal quality was sufficient for analysis in 93% and single‑lead ECG quality was sufficient in 94% of the participants. After removing insufficient quality measurements, the sensitivity and specificity were 96% (95% CI 89%-99%) and 97% (95% CI 91%-99%) for the PPG signal versus 95% (95% CI 88%-98%) and 97% (95% CI 91%-99%) for the single‑lead ECG, respectively. False-positive results were mainly because of premature ectopic beats. PPG and single‑lead ECG techniques yielded adequate signal quality in 196 subjects and a similar diagnosis in 98.0% (192/196) subjects.

Conclusions

The FibriCheck AF algorithm can accurately detect AF on the basis of mobile phone PPG and single-lead ECG signals in a primary care convenience sample.