Muscle Thickness and Curvature Influence Atrial Conduction Velocities

Electroanatomical mapping is currently used to provide clinicians with information about the electrophysiological state of the heart and to guide interventions like ablation. These maps can be used to identify ectopic triggers of an arrhythmia such as atrial fibrillation (AF) or changes in the conduction velocity (CV) that have been associated with poor cell to cell coupling or fibrosis. Unfortunately, many factors are known to affect CV, including membrane excitability, pacing rate, wavefront curvature, and bath loading, making interpretation challenging. In this work, we show how endocardial conduction velocities are also affected by the geometrical factors of muscle thickness and wall curvature. Using an idealized three-dimensional strand, we show that transverse conductivities and boundary conditions can slow down or speed up signal propagation, depending on the curvature of the muscle tissue. In fact, a planar wavefront that is parallel to a straight line normal to the mid-surface does not remain normal to the mid-surface in a curved domain. We further demonstrate that the conclusions drawn from the idealized test case can be used to explain spatial changes in conduction velocities in a patient-specific reconstruction of the left atrial posterior wall. The simulations suggest that the widespread assumption of treating atrial muscle as a two-dimensional manifold for electrophysiological simulations will not accurately represent the endocardial conduction velocities in regions of the heart thicker than 0.5 mm with significant wall curvature.

The safety and efficacy of second-generation cryoballoon ablation plus catheter ablation for persistent atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Growing evidence suggests that second-generation cryoballoon ablation (2G-CB) is effective in patients with persistent atrial fibrillation (PerAF). The cornerstone of atrial fibrillation (AF) ablation is pulmonary vein isolation (PVI). The purpose of this study was to summarize the available data on the safety and mid-term (≥ 12 months) effectiveness of a 'PVI-only' strategy vs. a 'PVI-plus' strategy using 2G-CB in patients with PerAF.

METHODS

We searched the PubMed, EMBASE and Cochrane library databases for studies on 2G-CB for PerAF. Group analysis was based on the ablation approach: 'PVI-only' versus 'PVI-plus', the latter of which involved PVI plus other substrate modifications. Studies showing clinical success rates at a follow-up (FU) of ≥ 12 months were included. Complication rates were also assessed. Data were analyzed by applying a fixed effects model.

RESULTS

A total of 879 patients from 5 studies were analyzed. After a mid-term FU of 27 months, the overall success rate of 2G-CB for PerAF was 66.1%. In the 'PVI-plus' group, the success rate was 73.8%. In the 'PVI-only' group, the success rate was 53.6%. No heterogeneity was noted among studies (I2 = 0.0%, P = 0.82). Complications occurred in 5.2% of patients (P = 0.93), and the rate of phrenic nerve (PN) injury was 2.8% (P = 0.14). Vascular assess complications were the most frequent at 1.6% (P = 0.33). No death or myocardial infarction was reported.

CONCLUSION

'PVI-plus' involving 2G-CB seems to be safe and effective for treating PerAF.

Mechanical discordance between left atrium and left atrial appendage

During standard transesophageal echocardiographic examinations in sinus rhythm (SR) patients, the left atrial appendage (LAA) is not routinely assessed with Doppler. Despite having a SR, it is still possible to have irregular activity in the LAA. This situation is even more important for SR patients where assessment of the left atrium is often foregone. We describe a case where we encountered this situation and briefly review how to assess the left atrium and its appendage in such a case scenario.

Effectiveness and safety of rivaroxaban vs. warfarin in patients with non-valvular atrial fibrillation and heart failure

Aims

Heart failure (HF) is a common co‐morbidity in non‐valvular atrial fibrillation (NVAF) patients and a potent risk factor for stroke, bleeding, and a decreased time‐in‐therapeutic range with warfarin. We assessed the real‐world effectiveness and safety of rivaroxaban and warfarin in NVAF patients with co‐morbid HF.

Methods and results

Using US Truven MarketScan Commercial and Medicare supplemental database claims data from 11/2011 to 12/2016, we identified oral anticoagulant (OAC)‐naïve NVAF patients with HF (International Classification of Diseases, 10th Revision codes of I50 or I09.81) and ≥12 months of insurance coverage prior to the qualifying OAC dispensing. Rivaroxaban users (20 or 15 mg once daily) were 1:1 propensity score matched to warfarin users, with residual absolute standardized differences <0.1 being achieved for all covariates after matching. Patients were followed up until an event, OAC discontinuation/switch, insurance disenrolment, or end of follow‐up. Rates [events per 100 person‐years (PYs) of follow‐up] for stroke or systemic embolism and major bleeding (using the Cunningham algorithm) were compared between the matched cohorts using Cox proportion hazard regression and reported as hazard ratios (HRs) with 95% confidence intervals (CIs). We matched 3418 rivaroxaban (32% receiving the reduced dose) and 3418 warfarin users with NVAF and HF with a median (interquartile range) available follow‐up of 1.4 (0.6, 2.5) years. Median age was 74 (63, 82) years, and median CHA₂DS₂‐VASc and HASBLED scores were 4 (3, 5) and 2 (2, 3). Common HF medications included beta‐blockers (64%), angiotensin‐converting enzyme inhibitors or angiotensin receptor blockers (62%), loop diuretics (46%), digoxin (11%), and aldosterone receptor antagonists (10%). The hazard of developing stroke or systemic embolism (0.98 events/100PY vs. 1.28 events/100PY; HR = 0.82, 95% CI = 0.47–1.44), ischaemic stroke (0.70 events/100PY vs. 1.02 events/100PY; HR = 0.77, 95% CI = 0.41–1.46), or major bleeding (3.86 events/100PY vs. 4.23 events/100PY; HR = 0.98, 95% CI = 0.73–1.31) was not found to be different between rivaroxaban and warfarin users. Intracranial haemorrhage was infrequent in both cohorts and numerically less with rivaroxaban (0.27 events/100PY vs. 0.36 events/100PY; HR = 0.73, 95% CI = 0.25–2.08).

Conclusions

Effectiveness and safety of rivaroxaban vs. warfarin are sustained in NVAF patients with co‐morbid HF treated in routine practice. The general consistency between this real‐world study and those from phase III randomized trial data of rivaroxaban should provide additional reassurance to clinicians regarding the use of rivaroxaban in NVAF patients with HF.

Outcomes Associated With Apixaban Use in Patients With End-Stage Kidney Disease and Atrial Fibrillation in the United States

BACKGROUND

Patients with end-stage kidney disease (ESKD) on dialysis were excluded from clinical trials of direct oral anticoagulants for atrial fibrillation (AF). Recent data have raised concerns regarding the safety of dabigatran and rivaroxaban, but apixaban has not been evaluated despite current labeling supporting its use in this population. The goal of this study was to determine patterns of apixaban use and its associated outcomes in dialysis-dependent patients with ESKD and AF.

METHODS

We performed a retrospective cohort study of Medicare beneficiaries included in the United States Renal Data System (October 2010 to December 2015). Eligible patients were those with ESKD and AF undergoing dialysis who initiated treatment with an oral anticoagulant. Because of the small number of dabigatran and rivaroxaban users, outcomes were only assessed in patients treated with apixaban or warfarin. Apixaban and warfarin patients were matched (1:3) based on prognostic score. Differences between groups in survival free of stroke or systemic embolism, major bleeding, gastrointestinal bleeding, intracranial bleeding, and death were assessed using Kaplan-Meier analyses. Hazard ratios (HRs) and 95% CIs were derived from Cox regression analyses.

RESULTS

The study population consisted of 25 523 patients (45.7% women; 68.2±11.9 years of age), including 2351 patients on apixaban and 23 172 patients on warfarin. An annual increase in apixaban prescriptions was observed after its marketing approval at the end of 2012, such that 26.6% of new anticoagulant prescriptions in 2015 were for apixaban. In matched cohorts, there was no difference in the risks of stroke/systemic embolism between apixaban and warfarin (HR, 0.88; 95% CI, 0.69-1.12; P=0.29), but apixaban was associated with a significantly lower risk of major bleeding (HR, 0.72; 95% CI, 0.59-0.87; P<0.001). In sensitivity analyses, standard-dose apixaban (5 mg twice a day; n=1034) was associated with significantly lower risks of stroke/systemic embolism and death as compared with either reduced-dose apixaban (2.5 mg twice a day; n=1317; HR, 0.61; 95% CI, 0.37-0.98; P=0.04 for stroke/systemic embolism; HR, 0.64; 95% CI, 0.45-0.92; P=0.01 for death) or warfarin (HR, 0.64; 95% CI, 0.42-0.97; P=0.04 for stroke/systemic embolism; HR, 0.63; 95% CI, 0.46-0.85; P=0.003 for death).

CONCLUSIONS

Among patients with ESKD and AF on dialysis, apixaban use may be associated with a lower risk of major bleeding compared with warfarin, with a standard 5 mg twice a day dose also associated with reductions in thromboembolic and mortality risk.

Left Atrial or Left Atrial Appendage Thrombus Resolution After Adjustment of Oral Anticoagulant Treatment

BACKGROUND

There are few reports about non-vitamin K antagonist oral anticoagulant (NOAC) treatment for resolution of left atrium (LA) or left atrial appendage (LAA) thrombus. LAA thrombus is an important cause of cardiogenic cerebral thromboembolism, and the detection rate increases due to more and more patients receiving catheter ablation. However, the results from NOAC use for LA or LAA thrombus are still unknown in real-world practice. The aim of this study was to discover the resolution of LA or LAA thrombus after anticoagulant treatment in real-world practice.

METHOD

From January 2013 to December 2016, a total 864 patients underwent transesophageal echocardiography (TEE), and 41 cases of LA or LAA thrombus were detected in our hospital. Among them, a total of 22 patients underwent follow-up TEE to detect the resolution of LA or LAA thrombus.

RESULT

The average age of the study patients was 72.0 ± 11 years old, and 61% were male. The average CHA2DS2-VASc scores were 3.76 ± 2.01 points. A total of 22 patients underwent follow-up TEE, and 19 (86.4%) patients presented LA or LAA thrombus resolution. The average resolution duration was 258.47 ± 218.17 days. One-year all-cause mortality was 4.9%, and the incidence of ischemic stroke was 4.9%. Most physicians favored titration of the dosage of NOAC or warfarin in real-world practice.

CONCLUSION

In real-world practice, most physicians favored titration of the dosage of NOAC or warfarin for LA or LAA thrombus. LA or LAA thrombus could exist if the patient received a reduced dose of NOAC. High frequency of LAA or LA thrombi could resolve, and a low incidence of ischemic stroke occurred after adjustment of oral anticoagulant treatment.

Management of patients with stroke treated with direct oral anticoagulants

Since their market approval, direct oral anticoagulants (DOACs) are being increasingly used for stroke prevention in patients with atrial fibrillation. However, the management of DOAC-treated patients with stroke poses several challenges for physicians in everyday clinical practice, both in the acute setting and in long-term care. This has spurred extensive research activity in the field over the past few years, which we review here.

Percutaneous versus thoracoscopic ablation of symptomatic paroxysmal atrial fibrillation: a randomised controlled trial - the FAST II study

BACKGROUND

The most efficient first-time invasive treatment, for achieving sinus rhythm, in symptomatic paroxysmal atrial fibrillation has not been established. We aimed to compare percutaneous catheter and video-assisted thoracoscopic pulmonary vein radiofrequency ablation in patients referred for first-time invasive treatment due to symptomatic paroxysmal atrial fibrillation. The primary outcome of interest was the prevalence of atrial fibrillation with and without anti-arrhythmic drugs at 12 months.

METHODS

Ninety patients were planned to be randomised to either video-assisted thoracoscopic radiofrequency pulmonary vein ablation with concomitant left atrial appendage excision or percutaneous catheter pulmonary vein ablation. Episodes of atrial fibrillation were defined as more than 30 s of atrial fibrillation observed on Holter monitoring/telemetry or clinical episodes documented by ECG.

RESULTS

The study was terminated prematurely due to a lack of eligible patients. Only 21 patients were randomised and treated according to the study protocol. Thoracoscopic pulmonary vein ablation was performed in 10 patients, and 11 patients were treated with catheter ablation. The absence of atrial fibrillation without the use of anti-arrhythmic drugs throughout the follow-up was observed in 70% of patients following thoracoscopic pulmonary vein ablation and 18% after catheter ablation (p < 0.03).

CONCLUSION

Thoracoscopic pulmonary vein ablation may be superior to catheter ablation for first-time invasive treatment of symptomatic paroxysmal atrial fibrillation with regard to obtaining sinus rhythm off anti-arrhythmic drugs 12 months postoperative.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01336075 . Registered April 15th, 2011.

Female Sex as a Risk Factor for Ischemic Stroke and Systemic Embolism in Chinese Patients With Atrial Fibrillation: A Report From the China-AF Study

Background Previous studies have provided conflicting results as to whether women are at higher risk than men for thromboembolism in the setting of atrial fibrillation ( AF ). We investigated whether women with AF were at higher risk of ischemic stroke in the China-AF (China Atrial Fibrillation Registry) Study. Methods and Results A total of 19 515 patients were prospectively enrolled between August 2011 and December 2016 in the China- AF Study. After exclusion of patients receiving anticoagulation or ablation therapy, 6239 patients (2574 women) with results from at least 6 months of follow-up were used for the analysis. Cox proportional hazards models were performed to evaluate whether female sex was an independent risk factor for thromboembolism after multivariate adjustment. The primary outcome was the time to the first occurrence of ischemic stroke or systemic embolism. After a mean follow-up of 2.81±1.46 years, 152 female patients reached the primary outcome, as compared with 172 male patients. Crude incidence rates of thromboembolism between women and men were of borderline statistical significance (2.08 versus 1.68 per 100 patient-years, P=0.058). After multivariable analysis, female sex was not independently associated with an increased thromboembolism risk (hazard ratio 1.09, 95% confidence interval 0.86-1.39). There was no significant difference in thromboembolism risk by sex stratified by age and presence or absence of risk factors ( P for interaction all >0.1). Conclusions Although crude incidence rates of thromboembolism were higher in Chinese female patients with AF compared with male patients, female sex did not emerge as an independent risk factor for thromboembolism on multivariate analysis. Clinical Trial Registration URL : http://www.chictr.org.cn/ . Unique identifier: Chi CTR - OCH -13003729.

Expert opinion paper on atrial fibrillation detection after ischemic stroke

This expert opinion paper on atrial fibrillation detection after ischemic stroke includes a statement of the "Heart and Brain" consortium of the German Cardiac Society and the German Stroke Society. This paper was endorsed by the Stroke Unit-Commission of the German Stroke Society and the German Atrial Fibrillation NETwork. In patients with ischemic stroke, detection of atrial fibrillation should usually lead to a change in secondary stroke prevention, since oral anticoagulation is superior to antiplatelet drugs. The detection of previously undiagnosed atrial fibrillation can be improved in patients with ischemic stroke to optimize stroke prevention. This paper summarizes the present knowledge on atrial fibrillation detection after ischemic stroke. We propose an interdisciplinary standard for a "structured analysis of ECG monitoring" on the stroke unit as well as a staged diagnostic scheme for the detection of atrial fibrillation. Since the optimal duration and mode of ECG monitoring has not yet been finally established, this paper is intended to give advice to physicians who are involved in stroke care. In line with the nature of an expert opinion paper, labeling of classes of recommendations is not provided, since many statements are based on the expert opinion, reported case series and clinical experience. Therefore, this paper is not intended as a guideline.

Management of Anticoagulation in Patients with Atrial Fibrillation Undergoing PCI: Double or Triple Therapy?

PURPOSE OF REVIEW

This review aims to discuss the use of antithrombotic therapy in patients with atrial fibrillation who undergo coronary stenting with emphasis on the use of double vs triple therapy.

RECENT FINDINGS

When combined with systemic anticoagulation, dual antiplatelet therapy results in an unacceptable increase in bleeding without any improvement in prevention of thrombotic events. Direct oral anticoagulants combined with single antiplatelet therapy have reduced bleeding compared with warfarin plus dual antiplatelet therapy. Triple anticoagulation therapy with warfarin or direct oral anticoagulants leads to an excess of bleeding and is not superior in preventing thrombotic events. Recent randomized, controlled trials have shown a significant reduction in major bleeding events in patients treated with dual antithrombotic therapy compared with triple therapy without any difference in efficacy. These findings call into question whether triple therapy should remain a part of standard practice.

Antithrombotic treatment is associated with intraplaque haemorrhage in the atherosclerotic carotid artery: a cross-sectional analysis of The Rotterdam Study

Aims

Antithrombotic treatment plays a key role in stroke prevention, but their direct effects on the composition of carotid artery atherosclerotic plaques are unknown. To investigate the association of antithrombotic treatment with carotid artery plaque composition, with a specific focus on an intraplaque haemorrhage (IPH).

Methods and results

From the population-based Rotterdam Study, 1740 participants with carotid atherosclerosis on ultrasound (mean age 72.9 years, 46.0 women) underwent magnetic resonance imaging of the carotid arteries to assess plaque composition. Information on the use of oral anticoagulants [vitamin K antagonists (VKA)] and antiplatelet agents (salicylates), including duration of use and dosage, was obtained from pharmacy records for all participants. We used logistic regression models to assess the association between the use of anticoagulants and antiplatelet agents, and the different plaque components adjusting for confounders. Current and past use of VKA [adjusted odds ratio (OR): 1.88, 95% confidence interval (CI): 0.74-4.75 and OR 1.89, 95% CI: 0.91-3.93] and antiplatelet agents (OR: 1.22, 95% CI: 0.91-1.62), and (OR: 1.23, 95% CI: 0.86-1.75) showed positive trend with a higher presence of IPH. Also, a longer duration of use was associated with a higher frequency of IPH (OR: 3.15, 95% CI: 1.23-8.05) for the use of VKA, and longer duration of the use for antiplatelet agents showed a positive trend (OR: 1.21, 95% CI: 0.88-1.67). We also found that higher levels of international normalized ratio above 2.97 for VKA (OR: 1.48, 95% CI: 1.03-2.15) and higher daily defined dosage than 1.0 for antiplatelet agents (OR: 1.50, 95% CI: 1.21-1.87) were related to a higher frequency of IPH. We found no association with lipid core or calcification.

Conclusions

The use of antithrombotic treatment relates to a higher frequency of IPH in carotid atherosclerotic plaques.

Predicting Bleeding Events in Anticoagulated Patients With Atrial Fibrillation: A Comparison Between the HAS-BLED and GARFIELD-AF Bleeding Scores

Background Patients with atrial fibrillation (AF) treated with oral anticoagulants may be exposed to an increased risk of bleeding events. The HAS-BLED (Hypertension, Abnormal renal and liver function, Stroke, Bleeding, Labile INRs, Elderly, Drugs or alcohol) score is a simple, well-established, clinical bleeding-risk prediction score. Recently, a new algorithm-based score was proposed, the GARFIELD-AF (Global Anticoagulant in the Field-AF) bleeding score. We compared HAS-BLED and GARFIELD-AF scores in predicting adjudicated bleeding events in a clinical trial cohort of patients with AF taking anticoagulants, in the first external comparative validation of both scores. Methods and Results We analyzed patients from the SPORTIF (Stroke Prevention Using an Oral Thrombin Inhibitor in Patients With AF) III and V trials. All patients assigned to the warfarin arm with information to calculate the scores were considered. Outcomes were major, major/clinically relevant nonmajor, and any bleeding. A total of 3550 warfarin-treated patients were available for analysis. Of these patients, 2519 (71.0%) had a HAS-BLED score ≥3, whereas based on GARFIELD-AF median value, 2056 (57.9%) were categorized as "high score." Both HAS-BLED and GARFIELD-AF C-indexes showed modest predictive value (C-index [95% confidence interval] for major bleeding, 0.58 [0.56-0.60] and 0.56 [0.54-0.57], respectively); however, GARFIELD-AF was not predictive of any bleeding. The GARFIELD-AF bleeding score had a significantly lower sensitivity and a negative reclassification for any bleeding compared with HAS-BLED, assessed by integrated discrimination improvement and net reclassification improvement (both P<0.001). HAS-BLED showed a 5% net benefit for any bleeding occurrence. Conclusions The algorithm-based GARFIELD-AF bleeding score did not show any significant improvement in major and major/clinically relevant nonmajor prediction compared with the simple HAS-BLED score. For clinical usefulness in prediction of any bleeding, the HAS-BLED score showed a significant net benefit compared with the GARFIELD-AF.

Atrial Fibrillation and Risk of Cancer: A Danish Population-Based Cohort Study

Background Atrial fibrillation ( AF ) and cancer are frequent diseases worldwide. The timewise association between the diagnosis of AF and a subsequent diagnosis of cancer may clarify whether a mutual cause exists, and may also guide clinicians about time windows of high risk of cancer occurrence. Methods and Results We conducted a population-based cohort study among 26 222 men and 28 879 women free of AF and cancer at baseline based on the Danish Diet, Cancer and Health study. The participants were followed for the development of AF (the Danish National Patient Registry) and subsequent cancer (the Danish Cancer Registry) until 2013. We used Cox proportional hazard models with new-onset AF as time-dependent exposure. The men (median age 56 years) and women (median age 56 years) were followed for medians of 16.7 and 19.6 years, respectively. AF was associated with higher risks of any type of cancer (men: hazard ratio [ HR ] 1.41, 95% confidence interval [ CI ], 1.26-1.58; women: HR 1.15, 95% CI , 1.02-1.32), and for men only, lung ( HR 1.66, 95% CI , 1.19-2.30), and colorectal cancer ( HR 1.37, 95% CI , 1.02-1.85). Within the initial 90 days following the diagnosis of AF , the risks of any type of cancer (men: HR 2.89, 95% CI , 2.10-3.98; women: HR 3.72, 95% CI , 2.49-5.56), lung (men: HR 7.70, 95% CI , 4.34-13.68; women: HR 7.98, 95% CI , 3.96-16.09), and colorectal cancer (men: HR 3.35, 95% CI , 1.03-10.90; women: HR 5.91, 95% CI , 2.44-14.29) were higher for men and women. Conclusions A diagnosis of AF is associated with a higher incidence rate of cancer among men and women. The cancer incidence rate is particularly elevated within 90 days after the diagnosis of AF .

Preparation for and Implementation of Shared Medical Appointments to Improve Self-Management, Knowledge, and Care Quality Among Patients With Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia in adults and is associated with an increased risk of stroke, heart failure, and death. Therapy for this pervasive arrhythmia is complex, involving multiple options that chiefly manage symptoms and prevent stroke. Current therapeutic strategies are also of limited efficacy, and can present potentially life-threatening side effects and/or complications. Emerging research suggests that the burden of AF can be reduced by improving patient understanding of the arrhythmia and teaching patients to adopt and maintain lifestyle and behavior changes. Shared medical appointments (SMAs) have been successfully used to deliver education and develop patient coping and disease management skills for patients with complex needs, but there is a paucity of studies examining the use of SMAs for managing AF. Moreover, few studies have examined strategies for implementing SMAs into routine clinical care. We detail our approach for (1) adapting a patient-centered SMA curriculum; (2) designing an evaluation comparing SMAs to routine care on patient outcomes; and (3) implementing SMAs into routine clinical practice. We conclude that evaluation and implementation of SMAs into routine clinical practice requires considerable planning and continuous engagement from committed key stakeholders, including patients, family members, schedulers, clinical staff, nurse educators, administrators, and billing specialists.

Antithrombotic Therapy After Percutaneous Coronary Intervention in Atrial Fibrillation: The Triple Trouble

One of the most common conundrums in all cardiovascular medicine pertains to the care of patients with atrial fibrillation after percutaneous coronary intervention, because of both dual antiplatelet therapy and oral anticoagulant therapy would seem to be necessary to reduce risks of stent thrombosis and thromboembolism, respectively, but also with an inevitable trade-off of more bleeding. Patients who require triple therapy are at high risk of both ischaemia and bleeding; therefore, defining a personalised secondary prevention strategy aimed at achieving the best net clinical benefit is essential. The good news is that we have entered an era of increased perceived and tangible safety that applies to both non-vitamin K-antagonist oral anticoagulants and newer drug-eluting stents. Even if the consistency across the major trials and the significantly lower risk of bleeding with dual therapy make it hard to argue that triple therapy should be used routinely, the aggregate evidence suggests that the net clinical benefit of dual therapy should give cardiologists confidence to drop aspirin when they are using a contemporary percutaneous coronary intervention strategy with drug-eluting stents. Waiting for more randomised trials and meta-analyses, for the time being, in patients not in clinical trials, full-dose oral triple therapy with dual antiplatelet agents and full-dose anticoagulation should be avoided as a routine practice, and the choice of the proper, that is, safer, oral anticoagulant, namely a non-vitamin K-antagonist oral anticoagulant, may be regarded by now as an additional bleeding avoiding strategy in patients with atrial fibrillation undergoing percutaneous coronary intervention.

Anticoagulation in atrial fibrillation with factor X deficiency-A management dilemma

Factor X (FX) deficiency is a rare bleeding disorder. There is currently no clear guideline or recommendation for the appropriate selection of anticoagulation and management of patients with FX deficiency who require anticoagulation. We shared our experience in managing such patient, and we further discussed other possible treatment options.

Creation and Implementation of an Outpatient Pathway for Atrial Fibrillation in the Emergency Department Setting: Results of an Expert Panel

Atrial fibrillation and flutter (AF) is a common condition among emergency department (ED) patients in the United States. Traditionally, ED care for primary complaints related to AF focus on rate control, and patients are often admitted to an inpatient setting for further care. Inpatient care may include further telemetry monitoring and diagnostic testing, rhythm control, a search for identification of AF etiology, and stroke prophylaxis. However, many patients are eligible for safe and effective outpatient management pathways. They are widely used in Canada and other countries but less widely adopted in the United States. In this project, we convened an expert panel to create a practical framework for the process of creating, implementing, and maintaining an outpatient AF pathway for emergency physicians to assess and treat AF patients, safely reduce hospitalization rates, ensure appropriate stroke prophylaxis, and effectively transition patients to longitudinal outpatient treatment settings from the ED and/or observation unit. To support local pathway creation, the panel also reached agreement on a protocol development plan, a sample pathway, consensus recommendations for pathway components, sample pathway metrics, and a structured literature review framework using a modified Delphi technique by a technical expert panel of emergency medicine, cardiology, and other stakeholder groups.

Prognostic efficacy of platelet count in patients with nonvalvular atrial fibrillation

BACKGROUND

The prognostic efficacy of quantitative platelet activity in atrial fibrillation (AF) remains unclear.

OBJECTIVE

The purpose of this study was to evaluate the platelet count (PLT) as a prognostic indicator in patients with nonvalvular AF.

METHODS

Data on 10,978 patients with nonvalvular AF were retrieved from a prospective registry of a single medical center in Korea. Cumulative risk for stroke and bleeding events were compared between patients with normal PLT (n = 8322), mild thrombocytopenia (n = 1791), and moderate to severe thrombocytopenia (n = 865) after propensity score matching. Prediction models for stroke were derived by conventional risk factors (model 1) and by combining PLT with model 1 (model 2), and model performance was assessed by area under the receiver operator characteristics curve (AUC).

RESULTS

During the follow-up period, 7.3%, 7.0%, and 4.5% had stroke and 7.6%, 10.8%, and 17.2% had bleeding events in the normal PLT, mild, and moderate to severe thrombocytopenia groups, respectively. Compared to the normal PLT group, the moderate to severe thrombocytopenia group showed a lower risk of stroke (hazard ratio [HR] 0.57; 95% confidence interval [CI] 0.40-0.80; P = .002). A reverse relationship was found between PLT and bleeding risk (moderate to severe thrombocytopenia: HR 2.19; 95% CI 1.77-2.70; P <.001; mild thrombocytopenia: HR 1.43; 95% CI 1.18-1.73; P <.001). Compared to model 1, model 2 showed significant improvement in risk prediction (AUC 0.628 vs 0.644; P <.001).

CONCLUSION

A lower PLT was associated with a lower risk of stroke and a higher risk of bleeding events. PLT combined with conventional risk factors showed significant improvement in prediction for stroke.

Stroke prevention in Europe: how are 11 European countries progressing toward the European Society of Cardiology (ESC) recommendations?

Purpose

Stroke is a leading cause of death and disability, although studies show that 90% of strokes can be prevented. The evidence base for stroke prevention is well established, and this study aimed to investigate how well European countries are adopting the European Society of Cardiology (ESC) guidelines, particularly toward implementation of the recommended best practice in stroke prevention.

Materials and methods

We developed a stroke prevention scorecard – populated with World Health Organization (WHO) data, secondary research, time-series data, and a survey of 550 physicians – to benchmark 11 European countries in the context of the ESC guidelines.

Results

All countries were found to have policies in place to manage general behavioral risk factors of noncommunicable disease (NCD), but we found that more needs to be done to address cardiovascular disease – specifically, stroke risk factors. Although ten of the countries in this study endorse the ESC cardiovascular clinical guidelines, implementation is lacking. Eight out of the 11 countries received the lowest score in regard to raising awareness around stroke, and 7 countries were found not to have a stroke registry. Among physicians surveyed in primary care it was reported that less than 30% of patients over 40 years old were screened for blood pressure, whereas even fewer were screened for atrial fibrillation; in 10 out of the 11 countries, less than 20% of patients over 65 years old were screened for atrial fibrillation.

Conclusion

Although progress is being made in managing the burden of NCDs, our findings reveal opportunities for improvement in the primary prevention of stroke. Further developments in strategic planning, raising awareness, and monitoring disease are required, as is research on barriers to the implementation of best practice screening of blood pressure and atrial fibrillation in primary care.

Apixaban compared to heparin/vitamin K antagonist in patients with atrial fibrillation scheduled for cardioversion: the EMANATE trial

Aim

The primary objective was to compare apixaban to heparin/vitamin K antagonist (VKA) in patients with atrial fibrillation (AF) and ≤48 h anticoagulation prior to randomization undergoing cardioversion.

Methods

One thousand five hundred patients were randomized. The apixaban dose of 5 mg b.i.d. was reduced to 2.5 mg b.i.d. in patients with two of the following: age ≥ 80 years, weight ≤ 60 kg, or serum creatinine ≥ 133 µmol/L. To expedite cardioversion, at the discretion of the investigator, imaging and/or a loading dose of 10 mg (down-titrated to 5 mg) was allowed. The endpoints for efficacy were stroke, systemic embolism (SE), and death. The endpoints for safety were major bleeding and clinically relevant non-major (CRNM) bleeding.

Results

There were 1038 active and 300 spontaneous cardioversions; 162 patients were not cardioverted. Imaging was performed in 855 patients, and 342 received a loading dose of apixaban. Comparing apixaban to heparin/VKA in the full analysis set, there were 0/753 vs. 6/747 strokes [relative risk (RR) 0; 95% confidence interval (95% CI) 0-0.64; nominal P = 0.015], no SE, and 2 vs. 1 deaths (RR 1.98; 95% CI 0.19-54.00; nominal P > 0.999). In the safety population, there were 3/735 vs. 6/721 major (RR 0.49; 95% CI 0.10-2.07; nominal P = 0.338) and 11 vs. 13 CRNM bleeding events (RR 0.83; 95% CI 0.34-1.89; nominal P = 0.685). On imaging, 60/61 with thrombi continued randomized treatment; all (61) were without outcome events.

Conclusions

Rates of strokes, systemic emboli, deaths, and bleeds were low for both apixaban and heparin/VKA treated AF patients undergoing cardioversion.

Clinical Trials.gov number

NCT02100228.

Apixaban in patients at risk of stroke undergoing atrial fibrillation ablation

Aims

It is recommended to perform atrial fibrillation ablation with continuous anticoagulation. Continuous apixaban has not been tested.

Methods and results

We compared continuous apixaban (5 mg b.i.d.) to vitamin K antagonists (VKA, international normalized ratio 2-3) in atrial fibrillation patients at risk of stroke a prospective, open, multi-centre study with blinded outcome assessment. Primary outcome was a composite of death, stroke, or bleeding (Bleeding Academic Research Consortium 2-5). A high-resolution brain magnetic resonance imaging (MRI) sub-study quantified acute brain lesions. Cognitive function was assessed by Montreal Cognitive Assessment (MoCA) at baseline and at end of follow-up. Overall, 674 patients (median age 64 years, 33% female, 42% non-paroxysmal atrial fibrillation, 49 sites) were randomized; 633 received study drug and underwent ablation; 335 undertook MRI (25 sites, 323 analysable scans). The primary outcome was observed in 22/318 patients randomized to apixaban, and in 23/315 randomized to VKA {difference -0.38% [90% confidence interval (CI) -4.0%, 3.3%], non-inferiority P = 0.0002 at the pre-specified absolute margin of 0.075}, including 2 (0.3%) deaths, 2 (0.3%) strokes, and 24 (3.8%) ISTH major bleeds. Acute small brain lesions were found in a similar number of patients in each arm [apixaban 44/162 (27.2%); VKA 40/161 (24.8%); P = 0.64]. Cognitive function increased at the end of follow-up (median 1 MoCA unit; P = 0.005) without differences between study groups.

Conclusions

Continuous apixaban is safe and effective in patients undergoing atrial fibrillation ablation at risk of stroke with respect to bleeding, stroke, and cognitive function. Further research is needed to reduce ablation-related acute brain lesions.

Risk factors for stroke and choice of oral anticoagulant in atrial fibrillation

PURPOSE

To investigate risk factors for stroke in patients initiating oral anticoagulants for atrial fibrillation in Norway and their association with receiving DOACs versus warfarin.

METHODS

From nationwide registries, we identified naïve users initiating treatment with warfarin, dabigatran, rivaroxaban, or apixaban for atrial fibrillation from 2010 to 2015 in Norway. We studied temporal changes in the CHA₂DS₂-VASc score and its component risk factors. We used multiple logistic regressions to identify CHA₂DS₂-VASc risk factors associated with receiving DOACs versus warfarin in 2015.

RESULTS

From 2010 to 2015, the yearly number of new oral anticoagulant users increased from 7588 to 13,344. All new users initiated warfarin in 2010, while 86% initiated a DOAC in 2015. The mean CHA₂DS₂-VASc score decreased from 3.2 (SD 1.7) to 3.1 (SD 1.6) in the same period. Vascular disease (0.56 [0.49-0.63]), congestive heart failure (OR 0.65 [95% CI 0.58-0.72]), and diabetes (0.83 [0.73-0.95]) decreased the odds of receiving DOACs instead of warfarin, and ischemic stroke/transient ischemic attack/arterial thromboembolism (1.31 [1.12-1.54]), age 65-74 (1.23 [1.06-1.43]), and female sex (1.22 [1.10-1.36]) increased it. Age ≥ 75 (reference age < 65) and hypertension had no impact.

CONCLUSIONS

The uptake of DOACs was rapid and spurred an increase in new users of oral anticoagulants for atrial fibrillation from 2010 to 2015 in Norway. The mean CHA₂DS₂-VASc score did not change substantially during this period. Vascular disease, heart failure, and diabetes were associated with initiation of warfarin, and previous stroke, age 65-74 and female sex with initiation of DOACs.

Efficacy and Safety of Non-Vitamin K Antagonist Oral Anticoagulants in Atrial Fibrillation Patients With Impaired Liver Function: A Retrospective Cohort Study

Background Patients with impaired liver function ( ILF ) were excluded from clinical trials that investigated non-vitamin K antagonist oral anticoagulants ( NOAC s) for stroke prevention in patients with atrial fibrillation. The aim of this study was to evaluate the efficacy and safety of NOAC s in atrial fibrillation patients with ILF . Methods and Results A cohort study based on electronic medical records was conducted from 2009 to 2016 at a multicenter healthcare provider in Taiwan and included 6451 anticoagulated atrial fibrillation patients (aged 76.7±7.0 years, 52.5% male). Patients were classified into 2 subgroups: patients with normal liver function (n=5818) and patients with ILF (n=633, 9.8%). Cox regression analysis was performed to investigate the risks of thromboembolism, bleeding, and death associated with use of NOAC s and warfarin in patients with normal liver function and ILF , respectively. In patients with normal liver function, compared with warfarin therapy (n=2928), NOAC therapy (n=4048) was associated with significantly lower risks of stroke or systemic embolism (adjusted hazard ratio: 0.75; 95% confidence interval, 0.65-0.88; P<0.001) and death (adjusted hazard ratio: 0.69; 95% confidence interval, 0.60-0.80; P<0.001) with no difference in major bleeding or gastrointestinal bleeding. In patients with ILF , compared with warfarin therapy (n=394), NOAC therapy (n=342) was associated with significantly lower risk of death (adjusted hazard ratio: 0.64; 95% confidence interval, 0.49-0.83; P<0.001), but no difference in stroke or systemic embolism, major bleeding, or gastrointestinal bleeding. Conclusions In atrial fibrillation patients with ILF , NOAC therapy and warfarin therapy were associated with similar risks of stroke or systemic embolism, major bleeding, and gastrointestinal bleeding.

Atrial Fibrillation Detection Using a Novel Cardiac Ambulatory Monitor Based on Photo-Plethysmography at the Wrist

Background Long-term continuous cardiac monitoring would aid in the early diagnosis and management of atrial fibrillation ( AF ). This study examined the accuracy of a novel approach for AF detection using photo-plethysmography signals measured from a wrist-based wearable device. Methods and Results ECG and contemporaneous pulse data were collected from 2 cohorts of AF patients: AF patients (n=20) undergoing electrical cardioversion ( ECV ) and AF patients (n=40) that were prescribed for 24 hours ECG Holter in outpatient settings ( HOL ). Photo-plethysmography and acceleration data were collected at the wrist and processed to determine the inter-pulse interval and discard inter-pulse intervals in presence of motion artifacts. A Markov model was deployed to assess the probability of AF given irregular pattern in inter-pulse interval sequences. The AF detection algorithm was evaluated against clinical rhythm annotations of AF based on ECG interpretation. Photo-plethysmography recordings from apparently healthy volunteers (n=120) were used to establish the false positive AF detection rate of the algorithm. A total of 42 and 855 hours (AF: 21 and 323 hours) of photo-plethysmography data were recorded in the ECV and HOL cohorts, respectively. AF was detected with >96% accuracy ( ECV, sensitivity=97%; HOL , sensitivity=93%; both with specificity=100%). Because of motion artifacts, the algorithm did not provide AF classification for 44±16% of the monitoring period in the HOL group. In healthy controls, the algorithm demonstrated a <0.2% false positive AF detection rate. Conclusions A novel AF detection algorithm using pulse data from a wrist-wearable device can accurately discriminate rhythm irregularities caused by AF from normal rhythm.

Comparison of Radiofrequency Ablation and Cryoablation for the Recovery of Atrial Contractility and Survival

Background

Limited comparative data are available on the efficacy of cryoablation versus radiofrequency ablation in patients with atrial fibrillation. This study aimed to compare radiofrequency ablation and cryoablation with regard to clinical outcomes and the restoration of sinus rhythm or atrial contractility.

Methods

A total of 239 patients who underwent surgical ablation between August 2003 and December 2016 at our institution were included. The patients were divided into 2 groups according to the energy device that was used (group A: n=140, radiofrequency ablator; group B: n=99, cryoablator). Echocardiographic data, overall survival, and major cardiovascular and cerebrovascular event (MACCE)-free survival were compared between the 2 groups.

Results

At 1 year of follow-up, the atrial contractility recovery rate was 32.2% (19 of 59) in group A and 48.8% (21 of 44) in group B. In addition, cryoablation was found to be a predictive factor for the recovery of atrial contractility (cryoablation vs. radiofrequency ablation: odds ratio, 2.540; 95% confidence interval, 1.063–6.071; p=0.036). The left ventricular ejection fraction was significantly higher in group B (53.1%±11.5% vs. 59.1%±6.3%, p=0.001). The median follow-up duration was 36 months. The 5-year overall survival rate was 80.1%±3.6% in group A and 92.1%±2.9% in group B (p=0.400). The 5-year MACCE-free survival rate was 70.3%±4.0% in group A and 70.9%±5.6% in group B (p=0.818).

Conclusion

Cryoablation was associated with a higher atrial contractility restoration rate and better left ventricular function than radiofrequency ablation. However, no significant relationship was observed between the energy source and overall or MACCE-free survival.

The association of non-alcoholic fatty liver disease and atrial fibrillation: a review

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent and causes an enormous burden to human health and health-care systems all over the world. A great proportion of this burden results from increased risk of cardiovascular diseases. Atrial fibrillation (AF) is the most common chronic heart arrhythmia globally and it increases the risk of embolic stroke and heart failure. Recent studies have explored the association between NAFLD and AF with somewhat conflicting results. However, ultrasound-verified prospective studies concur that NAFLD is associated with the incidence of AF. According to epidemiological evidence, the greater the prevalence of NALFD in a population, the stronger the association with AF incidence and prevalence. Specifically, diabetic individuals with NAFLD are at the greatest risk of AF. Additionally, the risk of AF may concentrate most in individuals with advanced NAFLD, particularly those with liver fibrosis. The possible mechanistic factors between NAFLD and AF, particularly obesity and systemic inflammation, are diverse and form a complex interplaying network. However, further studies are needed to elucidate whether NAFLD has a causative role in the development of AF. The purpose of this article is to review and discuss the epidemiologic evidence and possible mechanistic links between these two conditions. KEY MESSAGES Although epidemiologic studies have provided conflicting results on the association of NAFLD and AF, prospective studies with ultrasound-verified NAFLD concur that NAFLD is associated with about 2-fold greater incidence of AF among general population and about 6-fold greater incidence among subjects with type 2 diabetes. The risk of AF among individuals with NAFLD is increased by other cardiovascular risk factors, especially type 2 diabetes and advanced age. The possible mechanistic links between NALFD and AF are diverse, with obesity and systemic inflammation having a significant role, but further studies are needed until NAFLD can be established as a causal factor in the incidence of AF.

New skip parameter to facilitate recurrence quantification of signals comprised of multiple components

Recurrence analyses are typically performed on discretized time series after applying proper embeddings, delays, and thresholds. In our study of atrial electrograms, we found limitations to this approach when sequential bipolar complexes were defined as the timings of the first two zero crosses following the initiation of each event. The reason for this is that each bipolar component consists of two points in odd-even pairings. Since recurrence analysis starts vectors on each sequential point, incorrect even-odd pairings occur for every other vector. To overcome this limitation, a new parameter SKIP is introduced such that recurrence vectors can skip 1 (or 2) points for signals with defined multiple components. To demonstrate the utility of parameter SKIP, we used the Courtemanche model to simulate the electrical activity in the human atrium on a square, two-dimensional plane with 800 × 800 nodes. Over this plane, a grid of 39 × 39 virtual unipoles was created. Neighboring unipoles formed 39 × 38 bipolar pairs, which were recorded as 1482 continuous and synchronous time series. At each unipolar site, the actual wavefront direction was determined by comparing the relative activation timings of the local intracellular potentials. Parameters were set such that the "tissue" exhibited both spiral waves (organized activity) and wave breakups (chaotic activity). For each bipolar complex in the continuous electrogram, discretized electrogram conformation was defined as the timing delays from the start of the complex to the first two zero-crosses. Long sequences of paired zero-cross timings were subjected to recurrence analysis using SKIP values of 0 (no skipping) and 1 (single skipping). Recurrence variables were computed and correlated with the absolute wavefront directions. The results showed that the introduction of the skipping window improved the correlations of some recurrence variables with absolute wavefront directions. This is critically important because such variables may be better markers for wavefront directions in human recordings when the absolute wavefront directions cannot be calculated directly.

Emergency Department Visits for Atrial Fibrillation in the United States: Trends in Admission Rates and Economic Burden From 2007 to 2014

Background

Atrial fibrillation (AF) is an increasingly prevalent public health problem and one of the most common causes of emergency department (ED) visits. We aimed to investigate the trends in ED visits and hospital admissions for AF.

Methods and Results

This is a repeated cross‐sectional analysis of ED visit‐level data from the Nationwide Emergency Department Sample for 2007 to 2014. We identified adults who visited EDs in the United States, with a principal diagnosis of AF. A sample of 864 759 ED visits for AF, representing a weighted total of 3 886 520 ED visits, were analyzed. The annual ED visits for AF increased by 30.7% from 411 406 in 2007 (95% confidence interval, 389 819–432 993) to 537 801 (95% confidence interval, 506 747–568 855) in 2014. Patient demographics remained consistent, with an average age of 69 to 70 years and slight female predominance (51%–53%) throughout the study period. Hospital admission rates were stable at ≈70% between 2007 and 2010, after which they gradually declined to 62% in 2014 (P_trend=0.017). Despite the decline in hospital admission rates, AF hospitalizations increased from 288 225 in 2007 to 333 570 in 2014 because of the increase in total annual ED visits during the study. The adjusted annual charges for admitted AF patients increased by 37% from $7.39 billion in 2007 to $10.1 billion in 2014.

Conclusions

Annual ED visits and hospital admissions for AF increased significantly between 2007 and 2014, despite a reduction in admission rates. These data emphasize the need for widespread implementation of effective strategies aimed at improving the management of patients with AF to reduce hospital admissions and the economic burden of AF.

The Left Atrial Appendage, Including LAA Occlusion Devices Line Watchman, Amulet, and Lariat

Atrial fibrillation is a very common arrhythmia whose prevalence is expected to increase significantly as the population ages. The associated stroke risk is a major cause of morbidity and mortality. Stroke prevention by anticoagulation carries its own risks, leading to the search for alternative strategies. Multiple techniques have been developed to exclude the left atrial appendage (the main source of thromboembolism in atrial fibrillation) from the circulation. Such techniques offer the hope of stroke prevention without the risks of anticoagulation. This article describes the percutaneous approaches being currently performed in the United States. Particular emphasis is placed on the use of transesophageal echocardiography to guide these procedures.

High-Normal Thyroid-Stimulating Hormone Shows a Potential Causal Association With Arrhythmia Recurrence After Catheter Ablation of Atrial Fibrillation

Background

Hypothyroidism has been shown to contribute to enhanced atrial arrhythmogenesis, resulting in atrial fibrillation (AF) development in animal models and clinical populations. We aimed to elucidate whether high thyroid‐stimulating hormone (TSH) levels are related to outcomes of catheter ablation of AF.

Methods and Results

Of 477 consecutive patients who underwent first‐time pulmonary vein isolation–based radiofrequency catheter ablation of AF, 456 with TSH above the lower limit of the normal range (age, 65.5±9.9 years; men, 73.9%; paroxysmal AF, 56.8%) were analyzed for this study. Atrial tachyarrhythmia recurrence for 3 years was compared across groups with hypothyroidism (n=23) and TSH quartile groups with euthyroidism (normal‐range TSH levels, n=433). Atrial tachyarrhythmia recurrence occurred in 179 patients (39%) after the first session. Patients with hypothyroidism had increased recurrence compared with patients with normal TSH levels (crude hazard ratio, 3.14 after the last session; P=0.001). When focusing on patients with normal TSH levels, recurrence‐free survivals after both the first and last sessions were significantly reduced in euthyroid patients with the highest quartile of TSH levels (quartile 4) compared with others (quartiles 1–3). Cox regression analysis identified high TSH levels as an independent predictor of atrial tachyarrhythmia recurrence after both the first (adjusted hazard ratio, 1.51; P=0.018) and last (adjusted hazard ratio, 1.86; P=0.023) sessions. The difference was more pronounced in patients with paroxysmal AF than in those with nonparoxysmal AF.

Conclusions

Not only hypothyroidism but also high‐normal TSH levels may be an independent predictor of atrial tachyarrhythmia recurrence after catheter ablation of AF.

Cardiac Arrhythmias and Pregnancy

PURPOSE OF REVIEWS

In this review, the challenges of managing cardiac arrhythmias and syncope in the setting of pregnancy will be discussed.

RECENT FINDINGS

Arrhythmias in pregnancy are increasing, as diagnostic and therapeutic options have advanced and women are older at the time of gestation. Atrial fibrillation has become the most common arrhythmia in pregnancy. Inherited arrhythmia has become a more common entity, with advances in treatments and genetic testing, and require specialized treatments in pregnancy. The majority of arrhythmias in pregnancy are benign. The potential risk of increased cardiac morbidity and mortality exists for mother and fetus, especially in women with structural heart disease, which is becoming increasingly common. Early evaluation, diagnosis, and appropriate treatment are necessary to achieve optimal outcomes for both mother and fetus.

Prognostic significance of atrial fibrillation in acute decompensated heart failure with reduced versus preserved ejection fraction

OBJECTIVE

The prognostic impact of atrial fibrillation (AF) in patients with acute decompensated heart failure (ADHF) has not been fully elucidated yet. Aim of the present study was thus to investigate the association of AF with all-cause mortality in patients with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF).

METHODS

We performed a retrospective single center study and analyzed data of 1286 patients admitted for ADHF. Patients were grouped according to AF status (i.e., "never AF", "history of AF", or "AF on admission") and type of heart failure. Patient and treatment characteristics were extracted by chart review. The primary outcome of all-cause mortality within 3 years following index hospitalization was determined by death registry linkage.

RESULTS

In total, 529 (41.1%), 215 (16.7%), and 542 (42.1%) patients were grouped as "never AF", "history of AF", and "AF on admission", respectively. With regard to type of heart failure, 558 (43.4%) and 728 (56.6%) had HFrEF and HFpEF, respectively. Compared to "never AF", "AF on admission" was associated with increased all-cause mortality in an adjusted Cox regression model [hazard ratio, 1.64 (95% confidence interval 1.32-2.04); P < 0.001]. However, this association remained significant only for patients with HFpEF [2.16 (1.58-2.95)], but not for patients with HFrEF [1.18 (0.85-1.63)] in a subgroup analysis (P for effect modification = 0.020).

CONCLUSIONS

AF is common in the setting of ADHF and is associated with increased all-cause mortality. However, this association remained significant only in patients with HFpEF, but not in patients with HFrEF.

Subclinical atrial fibrillation frequency and associated parameters in patients with cardiac resynchronization therapy

AIM

The presence of subclinical atrial fibrillation (SCAF) is relevant to issues such as the risk of stroke and the necessity of anticoagulant use in patients with cardiac resynchronization therapy (CRT). Our study aimed to investigate SCAF frequency and associated parameters in patients with CRT.

METHODS

One hundred ninety-one patients with CRT (77 females, 114 males, mean age 65.9 ± 9.8) were included in the study. Atrial high-rate episodes detected by the device, atrial electrode impedance, P-wave sense amplitude, and atrial lead threshold values were measured during pacemaker controls. SCAF was defined as asymptomatic atrial high-rate episodes (AHRE) longer than 6 min and shorter than 24 h. Patients were divided into two groups as with and without SCAF.

RESULTS

SCAF was detected in 44 (23.2%) of 191 patients with CRT. Age, sex, weight, aortic end-systolic diameter, left atrium (LA) diameter, left bundle branch block morphology, CHA2DS2-VASc score, and right atrium thresholds were associated with SCAF. In multivariate regression analysis, CHA2DS2-VASc score, LA diameter, and atrial threshold values were found to be independent predictors of SCAF occurrence. According to this analysis, every 1 point increase in CHA2DS2-VASc score, every 1 mm increase in LA diameter, and every 0.1 V increase in atrial threshold increased the risk of SCAF by 32.5, 59.6, and 14.6%, respectively. In the ROC analysis, the area under the curve (AUC) was 0.870, 0.638, and 0,652 for LA diameter, CHA2DS2-VASc score, and atrial lead threshold, respectively (p < 0.05, for all). The cut-off values were 34 mm, 3, and 0.6 V for LA diameter, CHA2DS2-VASc score, and atrial lead threshold, respectively.

CONCLUSION

Patients with CRT have significantly higher frequency of SCAF than the normal population. CHA2DS2-VASc score, LA diameter, and atrial threshold values were considered to be useful and easily applicable parameters in identifying the patients to develop SCAF.

Antiplatelet Agents in Secondary Stroke Prevention: Selection, Timing, and Dose

PURPOSE OF REVIEW

This narrative review critically evaluated the published studies regarding the systematic use of antiplatelet agents for secondary stroke prevention.

RECENT FINDINGS

Stroke is a leading cause of morbidity and mortality around the world. Multimodal prevention is the most viable strategy for reducing the societal burden of stroke recurrence. For secondary stroke prevention, antiplatelet therapy is at the core of effective long-term vascular risk reduction among survivors of an ischemic stroke or transient ischemic attack (TIA). In addition to aspirin, there are several antiplatelet agents proven to be efficacious in averting recurrent vascular events after an index ischemic stroke or TIA. However, beyond the challenges of keeping up with recent advances in antiplatelet drug options for secondary stroke prevention, questions linger about the most appropriate selection, timing, and dosing of antiplatelet treatment for a given patient. We narratively summarized the pharmacological properties of key antiplatelet drugs; discussed the evidence regarding efficacy, selection, timing, and dosing of various antiplatelet treatment regimens; and highlighted ongoing clinical trials identifying novel therapies with more favorable risk-benefit profiles than currently available antiplatelet agents for patients with a recent history of ischemic or TIA stroke. Finally, we reviewed published data on antiplatelet therapies that could potentially be applied in the management of commonly encountered challenging clinical scenarios.

A review of factors associated with maintenance of sinus rhythm after elective electrical cardioversion for atrial fibrillation

Atrial fibrillation is the most common heart-rhythm disorder, affecting about 1.5% to 2% of the population with an increased risk of mortality and morbidity due to stroke, thromboembolism, and heart failure. If the conversion back to sinus rhythm does not happen spontaneously, pharmacological or electrical cardioversion (ECV) is the next available treatment options for some patients. However, the long-term success following ECV is variable. This review describes the factors that are associated with maintenance of sinus rhythm following ECV and proposes a clinical strategy based on the available evidence.

Is the prescription right? A review of non-vitamin K antagonist anticoagulant (NOAC) prescriptions in patients with non-valvular atrial fibrillation. Safe prescribing in atrial fibrillation and evaluation of non-vitamin K oral anticoagulants in stroke prevention (SAFE-NOACS) group

BACKGROUND

Non-vitamin K antagonist oral anticoagulants (NOACs) are a major advance for stroke prevention in atrial fibrillation (AF). Use of the vitamin K antagonist (VKA), warfarin, has dropped 40% since 2010 in our institution. There is limited Irish hospital data on NOAC prescribing for stroke prevention.

METHOD

Single centre, retrospective observational cohort study of consecutive AF patients at increased risk of stroke and/or awaiting electrical cardioversion. Data on prescribed NOACs from February 2010 till July 2015 was collected from the electronic inpatient record. Appropriateness of prescriptions was based on CHA2DS2-VASC score and accuracy on individual NOAC SPCs. Potential drug interactions and bleeding risk were also quantified.

RESULTS

A total of 348 patients AF and increased risk of stroke (CHA2DS2-VASC score > 1 for men and > 2 for women) were studied. Forty-eight percent were female with a mean age 71 ± 18.6 years, 52% of whom were > 75. Mean CHA2DS2-Vasc and HAS-BLED scores were 4.1 ± 1.8 and 1.4 ± 0.8, respectively. Rivaroxaban, dabigatran and apixaban were prescribed to 154 (54.2%), 106 (34.3%) and 41 (13.2%) patients, respectively. 20.4% had inaccurate prescriptions; 92.9% (n = 65) underdosed and 7.1% (n = 5) on inappropriately higher doses. Neither choice of NOAC, age, history of anaemia, previous bleeding or co-prescribed antiplatelets influenced the accuracy of prescription (p = NS), but decreased renal function appeared to do so (p = 0.05).

CONCLUSION

Our study highlights significant inaccuracies in NOAC prescribing. Patients commenced on NOACs should be assessed and followed up in a multidisciplinary AF clinic to ensure safe and effective prescribing and stroke prevention.