ACC/AHA/ESC 2006 Guidelines for the Management of Patients with Atrial Fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Revise the 2001 Guidelines for the Management of Patients With Atrial Fibrillation): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society

Transcatheter aortic valve replacement in the setting of left atrial appendage thrombus

OBJECTIVES

Left atrial appendage thrombus (LAT) was an exclusion criterion in the seminal transcatheter aortic valve replacement (TAVR) trials; however, such patients do undergo TAVR in the 'real-world' setting. This study sought to analyse outcomes after TAVR in patients with LAT or spontaneous echo contrast (SEC).

METHODS

All patients undergoing TAVR at our institution between March 2009 and December 2014 were prospectively analysed. The presence of LAT or SEC was determined via a retrospective chart review. Primary outcomes included 30-day and 1-year neurological events as well as mortality.

RESULTS

Of the 369 patients undergoing TAVR, 3.8% (14) were found to have LAT and 6.8% (25) were found to have SEC, and they were separately compared to patients who did not have LAT or SEC. Significant differences were noted between groups with regard to preoperative renal function, atrial fibrillation and ejection fraction. Preoperative atrial fibrillation was the only independent predictor of LAT. No perioperative complications were associated with the presence of LAT or SEC. Specifically, no patient with LAT or SEC experienced a postoperative neurological event. While neither LAT nor SEC was an independent predictor of 30-day mortality, LAT was an independent predictor of 1-year mortality (odds ratio 3.573, 95% confidence interval 1.040-12.28; P = 0.042).

CONCLUSIONS

The current study suggests that TAVR may be performed in patients with LAT and SEC with a low risk of embolic complications. While neither was an independent predictor of 30-day mortality, LAT was an independent predictor of 1-year mortality. Larger studies are needed to better study this phenomenon.

Embolus Analog Trajectory Paths Under Physiological Flowrates Through Patient-Specific Aortic Arch Models

Atrial fibrillation (AF) is the most common irregular heartbeat among the world's population and is a major contributor to cardiogenic embolisms and acute ischemic stroke (AIS). However, the role AF flow plays in the trajectory paths of cardiogenic emboli has not been experimentally investigated. A physiological simulation system was designed to analyze the trajectory patterns of bovine embolus analogs (EAs) (n = 720) through four patient-specific models, under three flow conditions: steady flow, normal pulsatile flow, and AF pulsatile flow. It was seen that EA trajectory paths were proportional to the percentage flowrate split of 25–31% along the branching vessels. Overall, AF flow conditions increased trajectories through the left- (LCCA) and right (RCCA)-common carotid artery by 25% with respect to normal pulsatile flow. There was no statistical difference in the distribution of clot trajectories when the clot was released from the right, left, or anterior positions. Significantly, more EAs traveled through the brachiocephalic trunk (BCT) than through the LCCA or the left subclavian. Yet of the EAs that traveled through the common carotid arteries, there was a greater affiliation toward the LCCA compared to the RCCA (p < 0.05).

Evaluation of drugs used in chronic heart failure at tertiary care centre: a hospital based study

Introduction: There is lack of data on pattern of use of drugs in patients with chronic heart failure (CHF) from Nepalese population. This study was conducted to explore the trends of evidence based medications used for CHF in our population.

Methods: This is a cross-sectional study on 200 consecutive patients with New York Heart Association (NYHA) class II to IV symptoms of CHF who attended cardiology clinic or admitted from September 2017 to August 2018 at Nobel Medical College Teaching Hospital, Biratnagar, Nepal.

Results: Mean age of patients was 54 (range 15-90) years. Ischemic cardiomyopathy, rheumatic heart disease, dilated cardiomyopathy, hypertensive heart disease, peripartum cardiomyopathy were common etiologies of CHF. Analysis of drugs used in CHF revealed that 85% patients were prescribed diuretics, 58.5% angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs), 53% mineralocorticoid receptor antagonists (MRAs), 38% beta-blockers (BBs) and 24% digoxin. Digoxin was mainly used as add on therapy for patients with atrial fibrillation (24% of all patients). Antithrombotics (warfarin or aspirin), inotropic agents (dopamine, dobutamine or noradrenaline), antiarrhythmic agent (amiodarone) and nitrates (intravenous glyceryl trinitrate or oral isosorbide dinitrate) were prescribed for 48%, 28%, 5% and 6% patients respectively. All CHF patients with preserved or mid-range ejection fraction (25% of all patients) were prescribed diuretics along with antihypertensive drugs for hypertensive patients.

Conclusion: CHF is associated with significant morbidity and mortality due to associated co-morbidities and underuse of proven therapy like BBs, ACEIs or ARBs and MRAs. Careful attention to optimization of different drugs therapy in patients with CHF may help to improve patient outcomes.

Transmitral inflow wave and progression from paroxysmal to permanent atrial fibrillation in Asian people

Objective

Paroxysmal atrial fibrillation could progress to permanent atrial fibrillation. Whether the transmitral inflow waves could be used to predict progression from paroxysmal atrial fibrillation to permanent atrial fibrillation is unknown. Therefore, we investigated the association between the transmitral inflow waves and progression of paroxysmal atrial fibrillation.

Method

We performed a retrospective study by analysing clinical and echocardiographic data from 88 patients with paroxysmal atrial fibrillation. We excluded patients who had structural heart disease, significant valvular disease, cardiomyopathy, cardiac device implantation or a left ventricular ejection fraction <50%.

Result

The patients with progression to permanent atrial fibrillation were more likely to be male and had lower peak A velocity than those without progression. After adjusting for covariates, lower peak A velocity remained the independent predictor of progression to permanent atrial fibrillation (p=0.025).

Conclusion

The A velocity could be useful for predicting progression to permanent atrial fibrillation in Asian people.

Anticoagulation After Stroke in Patients With Atrial Fibrillation

Background and Purpose- Bridging therapy with low-molecular-weight heparin reportedly leads to a worse outcome for acute cardioembolic stroke patients because of a higher incidence of intracerebral bleeding. However, this practice is common in clinical settings. This observational study aimed to compare (1) the clinical profiles of patients receiving and not receiving bridging therapy, (2) overall group outcomes, and (3) outcomes according to the type of anticoagulant prescribed. Methods- We analyzed data of patients from the prospective RAF and RAF-NOACs studies. The primary outcome was defined as the composite of ischemic stroke, transient ischemic attack, systemic embolism, symptomatic cerebral bleeding, and major extracerebral bleeding observed at 90 days after the acute stroke. Results- Of 1810 patients who initiated oral anticoagulant therapy, 371 (20%) underwent bridging therapy with full-dose low-molecular-weight heparin. Older age and the presence of leukoaraiosis were inversely correlated with the use of bridging therapy. Forty-two bridged patients (11.3%) reached the combined outcome versus 72 (5.0%) of the nonbridged patients (P=0.0001). At multivariable analysis, bridging therapy was associated with the composite end point (odds ratio, 2.3; 95% CI, 1.4-3.7; P<0.0001), as well as ischemic (odds ratio, 2.2; 95% CI, 1.3-3.9; P=0.005) and hemorrhagic (odds ratio, 2.4; 95% CI, 1.2-4.9; P=0.01) end points separately. Conclusions- Our findings suggest that patients receiving low-molecular-weight heparin have a higher risk of early ischemic recurrence and hemorrhagic transformation compared with nonbridged patients.

Robotic navigation shows superior improvement in efficiency for atrial fibrillation ablation

Background

Because of the expanding atrial fibrillation (AF) burden, AF catheter ablation (CA) techniques have to become more efficient. Efficient AF CA procedures are characterized by successful pulmonary vein isolation (PVI) within reasonable procedure time. Currently there are many PVI techniques available and all show substantial improvements over time. However, the magnitude of improvement in procedural efficiency has not yet been compared between different techniques. The aim of this study was to compare efficiency improvement between manually (MAN) guided, cryoballoon (CB) and remote magnetic navigation (RMN) guided PVI.

Methods

A total of 221 patients were included in this retrospective study. Procedural parameters of 115 patients treated with first-generation PVI techniques (MAN-1, CB-1, RMN-1) performed in 2010, were compared to 106 patients who were treated with the latest, second generation techniques (MAN-2, CB-2, RMN-2). Efficiency was characterized by the following parameters: total ablation time, total procedure time, first pass isolation (FPI) (i.e. successful isolation after the first pulmonary vein (PV) encirclement) and touch-up rates.

Results

Every technique showed significant improvement of procedure times from the first to the second generation (P<0.001). In-between second generation techniques, the procedure times were comparable. The greatest magnitude of procedure time improvement was observed within the RMN groups (∆-180min), which was significantly greater compared to CB (∆-48 min, P<0.001) and MAN (∆-98min, P=0.011) groups. The highest FPI rates were observed in RMN-2 (78% and 74%; left and right PVs respectively), which was significantly higher compared to other techniques (MAN-2: 24% and 24%; CB-2: 50% and 48%; P<0.001).

Conclusions

The highest magnitude of efficiency improvement was detected in RMN guided PVI.

Venous Thromboembolism in Special Populations: Preexisting Cardiopulmonary Disease, Cirrhosis, End-Stage Renal Disease, and Asplenia

Venous thromboembolism (VTE) is a common cause of morbidity and mortality. Presence of preexisting conditions, such as cardiopulmonary diseases, cirrhosis, renal dysfunction, and asplenia, commonly occurs in VTE patients. Moreover, these conditions often are risk factors for developing VTE. These preexisting conditions make VTE diagnosis and treatment challenging and worsen outcomes. Current guidelines do not include detailed features in the diagnosis and management of patients with preexisting conditions. This review discusses presence of VTE in patients with preexisting cardiopulmonary diseases, cirrhosis, renal dysfunction, and asplenia.

Peripheral blood metabolite profiles associated with new onset atrial fibrillation

BACKGROUND

Peripheral blood metabolite profiles have yielded mechanistic insights into various cardiovascular disease states. We hypothesized that peripheral blood metabolite profiles would be associated with new onset atrial fibrillation (AF).

METHODS AND RESULTS

The study population comprised 1892 patients without AF at baseline, who, as part the MURDOCK Cardiovascular Disease Study molecular profiling cohort (n = 2023), had previously had determination of levels of 69 metabolites from frozen, fasting plasma specimens obtained during coronary angiography. We used Cox proportional hazards models to examine the association of 13 uncorrelated metabolite factors created from these data using principal components analysis (PCA) with new occurrences of AF during a median follow up of 2.8 (0.1-4.9) years. A total of 233 patients developed new AF (12.3%) during follow up. Patients with new onset AF were older (median 67 vs. 60 years); more often white (82 vs. 71%) and male (68 vs. 60%), and had more comorbidities than those who did not develop AF. After adjustment, PCA factor 1 (medium chain acylcarnitines; hazard ratio [HR]: 1.11 [1.01-1.22]), factor 2 (short chain dicarboxylacylcarnitines; HR: 1.21 [1.09-1.34]) and factor 5 (long chain acylcarnitines; HR: 1.19 [1.06-1.34]) were associated with new onset AF.

CONCLUSION

Metabolite profiles were associated with new onset AF among patients referred for coronary angiography. Validation of these observations in broader patient populations may provide better mechanistic insight into the development of AF, and may provide new opportunities for prevention and treatment.

Preventable Cases of Oral Anticoagulant-Induced Bleeding: Data From the Spontaneous Reporting System

Background

Despite the risk of bleeding is a well-known adverse effect of oral anticoagulants, there is scarce evidence on the preventability of oral anticoagulant-induced bleedings. Therefore, we investigated the potential risk factors related to preventable cases of oral anticoagulant-induced bleedings.

Methods

We performed a study using Individual Case Safety Reports (ICSRs) with an oral anticoagulant as suspected drug among those reported through the spontaneous reporting system of Campania Region from 1 July 2012 to 31 December 2017. The P-method was used for the preventability assessment of all cases of bleeding.

Results

In total, 58 cases out of 253 (22.9%) were preventable, and the most reported suspected drug was an indirect oral anticoagulant (warfarin). Sixty-eight critical criteria for preventability were identified, all related to healthcare professionals' practices. The most detected risk factor related to healthcare professionals' practices was the labeled drug-drug interaction for both direct and indirect oral anticoagulants.

Conclusion

Our findings describe the most reported risk factors for preventability of oral anticoagulant-induced bleedings. These factors may be useful for targeting interventions to improve pharmacovigilance activities in our regional territory and to reduce the burden of medication errors and inappropriate prescription.

Empowering podiatrists to perform pulse checks for opportunistic atrial fibrillation detection during annual diabetes foot checks

Objective

To determine whether training podiatrists to provide opportunistic screening for atrial fibrillation (AF) during the local diabetes foot check was feasible and whether it detects previously unknown AF.

Method

During the initiative, 45 podiatrists from across North Durham, Darlington and Durham Dales Easington and Sedgefield Clinical Commissioning Groups were trained to recognise heart irregularities when taking pulse readings of feet of patients with diabetes during their annual foot screening reviews.

Results

Over the course of the 3-month pilot, 5000 patients with diabetes had their feet pulse-tested. The project uncovered that for every 500 patients who had their feet checked, one new case of AF could be identified.

Conclusion

A report following the Podiatry and Atrial Fibrillation Case Finding scheme revealed that the National Health Service in the United Kingdom North East and North Cumbria area could benefit from potential cost savings in excess of £500 000. In 2013, the National Diabetes Information Service, Yorkshire and Humber Public Health Observatory estimated 231 777 people in the North East, North Cumbria, Hambleton and Richmondshire area with diabetes. Therefore 463 patients could be found with AF, preventing 23 strokes and saving £539 742 or in excess of £0.5 M.

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.

Effect of Catheter Ablation vs Antiarrhythmic Drug Therapy on Mortality, Stroke, Bleeding, and Cardiac Arrest Among Patients With Atrial Fibrillation: The CABANA Randomized Clinical Trial

IMPORTANCE

Catheter ablation is effective in restoring sinus rhythm in atrial fibrillation (AF), but its effects on long-term mortality and stroke risk are uncertain.

OBJECTIVE

To determine whether catheter ablation is more effective than conventional medical therapy for improving outcomes in AF.

DESIGN, SETTING, AND PARTICIPANTS

The Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation trial is an investigator-initiated, open-label, multicenter, randomized trial involving 126 centers in 10 countries. A total of 2204 symptomatic patients with AF aged 65 years and older or younger than 65 years with 1 or more risk factors for stroke were enrolled from November 2009 to April 2016, with follow-up through December 31, 2017.

INTERVENTIONS

The catheter ablation group (n = 1108) underwent pulmonary vein isolation, with additional ablative procedures at the discretion of site investigators. The drug therapy group (n = 1096) received standard rhythm and/or rate control drugs guided by contemporaneous guidelines.

MAIN OUTCOMES AND MEASURES

The primary end point was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Among 13 prespecified secondary end points, 3 are included in this report: all-cause mortality; total mortality or cardiovascular hospitalization; and AF recurrence.

RESULTS

Of the 2204 patients randomized (median age, 68 years; 37.2% female; 42.9% had paroxysmal AF and 57.1% had persistent AF), 89.3% completed the trial. Of the patients assigned to catheter ablation, 1006 (90.8%) underwent the procedure. Of the patients assigned to drug therapy, 301 (27.5%) ultimately received catheter ablation. In the intention-to-treat analysis, over a median follow-up of 48.5 months, the primary end point occurred in 8.0% (n = 89) of patients in the ablation group vs 9.2% (n = 101) of patients in the drug therapy group (hazard ratio [HR], 0.86 [95% CI, 0.65-1.15]; P = .30). Among the secondary end points, outcomes in the ablation group vs the drug therapy group, respectively, were 5.2% vs 6.1% for all-cause mortality (HR, 0.85 [95% CI, 0.60-1.21]; P = .38), 51.7% vs 58.1% for death or cardiovascular hospitalization (HR, 0.83 [95% CI, 0.74-0.93]; P = .001), and 49.9% vs 69.5% for AF recurrence (HR, 0.52 [95% CI, 0.45-0.60]; P < .001).

CONCLUSIONS AND RELEVANCE

Among patients with AF, the strategy of catheter ablation, compared with medical therapy, did not significantly reduce the primary composite end point of death, disabling stroke, serious bleeding, or cardiac arrest. However, the estimated treatment effect of catheter ablation was affected by lower-than-expected event rates and treatment crossovers, which should be considered in interpreting the results of the trial.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00911508.

Effectiveness and safety of electrical cardioversion for acute-onset atrial fibrillation in the emergency department: a real-world 10-year single center experience

OBJECTIVE

Despite limited evidence, electrical cardioversion of acute-onset atrial fibrillation (AAF) is widely performed in the emergency department (ED). The aim of this study was to describe the effectiveness and safety of electrical cardioversion of AAF performed by emergency physicians in the ED.

METHODS

All episodes of AAF electrically cardioverted in the ED were retrieved from the database for a 10-year period. Most patients not already receiving anticoagulants were given enoxaparin before the procedure (259/419). Procedural complications were recorded, and the patients were followed-up for 30 days for cardiovascular and hemorrhagic complications.

RESULTS

Four hundred nineteen eligible cases were identified; men represented 69%, and mean age was 61±13 years. The procedure was effective in 403 cases (96.2%; 95.4% in women, 96.5% in men), with considerable differences with respect to the age of the patients, the procedure being effective in 100% of patients aged 18 to 39 and only 68.8% in those >80 years. New ED visits (33/419) were identified within 30 days (31 due to atrial fibrillation/atrial flutter recurrence, 1 due to iatrogenic hypokalemia, 1 due to hypertensive emergency). No strokes, major bleeding, life-threatening arrhythmias or peripheral thromboembolism were recorded. Nine small and mild skin burns were observed.

CONCLUSION

Electrical cardioversion is an effective and safe procedure in the vast majority of patients, albeit less effective in patients aged >80 years. It appears reasonable to avoid anticoagulation in low-risk patients with AAF and administer peri-procedural heparin to all remaining patients. Long-term anticoagulation should be planned on an individual basis, after assessment of thromboembolic and hemorrhagic risk.

Atrioventricular block can be used as a risk predictor of clinical atrial fibrillation

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia, with its incidence making up nearly one‐third of all hospital admissions. Atrioventricular block (AVB) is a conduction abnormality along the atrioventricular node or the His‐Purkinje system. The relationship between atrioventricular conduction block and AF is controversial.

Hypothesis

This study is designed to observe whether there is a correlation between AVB and AF, and which type of AVB has the most obvious correlation with AF.

Methods

This study retrospectively reviewed 1345 patients. We classified the AVB according to the AVB classification criteria. One hundred and two patients were excluded, and the final total sample size was 1243 patients, including 679 patients in the AF group (378, 55.7% males) and 564 patients in the non‐AF group (287, 50.8% males). AF group and non‐AF group were compared to observe the relationship between AVB and AF.

Results

The I AVB have a relative statistical risk of 1.927 (95% confidence interval [CI]: 1.160‐3.203, P < 0.05) with the occurrence of AF. II AVB occupied the largest proportion, accounting for 67 cases (9.87%), and the statistical risk of II AVB in AF is 16.845 (95% CI: 6.099‐46.524, P < 0.000). III AVB has a comparative statistical risk of 17.599 (95% CI: 4.212‐73.541, P < 0.000).

Conclusions

The three types of AVB in the AF group were significantly higher than that in the non‐AF group. II AVB has the highest incidence rate compared with other types of AVB in the AF group. AVB can be used as a risk factor for AF occurrence.

Atrial fibrillation ablation strategies and outcome in patients with heart failure: insights from the German ablation registry

BACKGROUND

Heart failure (HF) and atrial fibrillation (AF) often coexist, but data on the prognostic value of differing ablation strategies according to left ventricular ejection fraction (LVEF) are rare.

METHODS AND RESULTS

From January 2007 until January 2010, 728 patients with HF were enrolled in the multi-center German ablation registry prior to AF catheter ablation. Patients were divided into three groups according to LVEF: HF with preserved LVEF (≥ 50%, HFpEF, n = 333), mid-range LVEF (40-49%, HFmrEF, n = 207), and reduced LVEF (< 40%, HFrEF, n = 188). Ablation strategies differed significantly between the three groups with the majority of patients with HFpEF (83.4%) and HFmrEF (78.4%) undergoing circumferential pulmonary vein isolation vs. 48.9% of patients with HFrEF. The latter underwent ablation of the atrioventricular (AV) node in 47.3%. Major complications did not differ between the groups. Kaplan-Meier survival analysis demonstrated a significant mortality increase in patients with HFrEF (6.1% in HFrEF vs. 1.5% in HFmrEF vs. 1.9% in HFpEF, p = 0.009) that was limited to patients undergoing ablation of the AV node.

CONCLUSIONS

Catheter ablation strategies differ significantly in patients with HFpEF, HFmrEF, and HFrEF. In almost 50% of patients with HFrEF AV-node ablation was performed, going along with a significant increase in mortality rate. These results should raise efforts to further evaluate the prognostic effect of ablation strategies in HF patients.

Early repolarization and risk of lone atrial fibrillation

INTRODUCTION

Early repolarization syndrome is a recently proposed condition characterized by an early repolarization pattern in the electrocardiogram (ECG) and ventricular fibrillation in the absence of structural heart abnormalities. Although some studies have suggested that early repolarization is associated with frequency of atrial fibrillation, the association of early repolarization with atrial fibrillation is not well known.

HYPOTHESIS

Early repolarization indicates the substrate for atrial fibrillation in addition to that for ventricular fibrillation.

METHOD

This study included 79 patients (57 men [72%]; age, 45 ± 12 years) aged less than 60 years who had paroxysmal lone atrial fibrillation and 395 age- and sex-matched healthy controls (patient:control ratio, 1:5). Patients who had structural heart disease, hypertension, diabetes, hyperthyroidism, history of successful resuscitation, or the Brugada type ECG were excluded. ECGs recorded during sinus rhythm were compared between patients with atrial fibrillation and healthy controls.

RESULTS

Early repolarization in the inferior and/or lateral leads was more common in patients with atrial fibrillation (25%) than controls (10%; P = 0.001). The location and magnitude of early repolarization were similar between the two groups. Other electrocardiographic measurements were not different between the two groups. Among patients with atrial fibrillation, there was no difference in clinical characteristics including age at atrial fibrillation development, sex, and body mass index between patients with early repolarization and those without early repolarization. Electrocardiographic measurements were not different between patients with early repolarization and those without early repolarization.

CONCLUSION

Early repolarization was associated with lone atrial fibrillation. Early repolarization may indicate increased susceptibility to atrial fibrillation.

Reversal effect of Zhigancao decoction on myocardial fibrosis in a rapid pacing-induced atrial fibrillation model in New Zealand rabbits

Objective

To evaluate the effect of Zhigancao decoction on reversal of right atrial myocardial fibrosis after rapid atrial pacing (RAP)-induced atrial fibrillation (AF).

Methods

New Zealand white rabbits were randomly divided into four groups: sham operation group (Group A: implanted electrodes, no RAP), pacing group (Group B: RAP-induced AF), Zhigancao soup water decoction Yin group (Group C: RAP-induced AF followed by Zhigancao soup Yin prescription twice a day for 30 days), and Zhigancao soup group (Group D: RAP-induced AF followed by Zhigancao water decoction twice a day for 30 days). The atrial myocardium was then examined for myocardial fibrosis by Masson staining, and protein expression of matrix metalloproteinase-9 (MMP-9) was immunohistochemically assessed. The right atrial appendage tissue field action potential duration (fAPD) was measured by microelectrode arrays.

Results

RAP successfully induced AF. Myocardial fibrosis was more severe in Groups B and C and less severe in Group D. Protein expression of MMP-9 was strongly positive in Groups B and C and weakly positive in Group D. The fAPD was significantly decreased in Groups B and C, but the decrease in Group D was not significant.

Conclusion

Zhigancao decoction can reverse AF-induced myocardial fibrosis in rabbits and shorten the fAPD.

Refining Prediction of Atrial Fibrillation-Related Stroke Using the P2-CHA2DS2-VASc Score

BACKGROUND

In people with atrial fibrillation (AF), periods of sinus rhythm present an opportunity to detect prothrombotic atrial remodeling through measurement of P-wave indices (PWIs)-prolonged P-wave duration, abnormal P-wave axis, advanced interatrial block, and abnormal P-wave terminal force in lead V1. We hypothesized that the addition of PWIs to the CHA2DS2-VASc score would improve its ability to predict AF-related ischemic stroke.

METHODS

We included 2229 participants from the ARIC study (Atherosclerosis Risk in Communities) and 700 participants from MESA (Multi-Ethnic Study of Atherosclerosis) with incident AF who were not on anticoagulants within 1 year of AF diagnosis. PWIs were obtained from study visit ECGs before development of AF. AF was ascertained using study visit ECGs and hospital records. Ischemic stroke cases were based on physician adjudication of hospital records. We used Cox proportional hazards models to estimate hazard ratios and 95% CIs of PWIs for ischemic stroke. Improvement in 1-year stroke prediction was assessed by C-statistic, categorical net reclassification improvement, and relative integrated discrimination improvement.

RESULTS

Abnormal P-wave axis was the only PWI associated with increased ischemic stroke risk (hazard ratio, 1.84; 95% CI, 1.33-2.55) independent of CHA2DS2-VASc variables, and that resulted in meaningful improvement in stroke prediction. The β estimate was approximately twice that of the CHA2DS2-VASc variables, and thus abnormal P-wave axis was assigned 2 points to create the P2-CHA2DS2-VASc score. This improved the C-statistic (95% CI) from 0.60 (0.51-0.69) to 0.67 (0.60-0.75) in ARIC and 0.68 (0.52-0.84) to 0.75 (0.60-0.91) in MESA (validation cohort). In ARIC and MESA, the categorical net reclassification improvements (95% CI) were 0.25 (0.13-0.39) and 0.51 (0.18-0.86), respectively, and the relative integrated discrimination improvement (95% CI) were 1.19 (0.96-1.44) and 0.82 (0.36-1.39), respectively.

CONCLUSIONS

Abnormal P-wave axis-an ECG correlate of left atrial abnormality- improves ischemic stroke prediction in AF. Compared with CHA2DS2-VASc, the P2-CHA2DS2-VASc is a better prediction tool for AF-related ischemic stroke.

Interventions for Preventing Thromboembolic Events in Patients With Atrial Fibrillation: A Systematic Review

BACKGROUND

The comparative safety and effectiveness of treatments to prevent thromboembolic complications in atrial fibrillation (AF) remain uncertain.

PURPOSE

To compare the effectiveness of medical and procedural therapies in preventing thromboembolic events and bleeding complications in adults with nonvalvular AF.

DATA SOURCES

English-language studies in several databases from 1 January 2000 to 14 February 2018.

STUDY SELECTION

Two reviewers independently screened citations to identify comparative studies of treatments to prevent stroke in adults with nonvalvular AF who reported thromboembolic or bleeding complications.

DATA EXTRACTION

Two reviewers independently abstracted data, assessed study quality and applicability, and rated strength of evidence.

DATA SYNTHESIS

Data from 220 articles were included. Dabigatran and apixaban were superior and rivaroxaban and edoxaban were similar to warfarin in preventing stroke or systemic embolism. Apixaban and edoxaban were superior and rivaroxaban and dabigatran were similar to warfarin in reducing the risk for major bleeding. Treatment effects with dabigatran were similar in patients with renal dysfunction (interaction P > 0.05), and patients younger than 75 years had lower bleeding rates with dabigatran (interaction P < 0.001). The benefit of treatment with apixaban was consistent in many subgroups, including those with renal impairment, diabetes, and prior stroke (interaction P > 0.05 for all). The greatest bleeding risk reduction was observed in patients with a glomerular filtration rate less than 50 mL/min/1.73 m2 (P = 0.003). Similar treatment effects were observed for rivaroxaban and edoxaban in patients with prior stroke, diabetes, or heart failure (interaction P > 0.05 for all).

LIMITATION

Heterogeneous study populations, interventions, and outcomes.

CONCLUSION

The available direct-acting oral anticoagulants (DOACs) are at least as effective and safe as warfarin for patients with nonvalvular AF. The DOACs had similar benefits across several patient subgroups and seemed safe and efficacious for a wide range of patients with nonvalvular AF.

PRIMARY FUNDING SOURCE

Patient-Centered Outcomes Research Institute. (PROSPERO: CRD42017069999).

Indoxyl Sulphate is Associated with Atrial Fibrillation Recurrence after Catheter Ablation

Renal dysfunction results in the accumulation of various uremic toxins, including indoxyl sulphate (IS), and is a major risk factor for atrial fibrillation (AF). Experimental studies have demonstrated that IS exacerbates atrial remodelling via oxidative stress, inflammation, and fibrosis. However, its clinical impact on AF-promoting cardiac remodelling has not been described. Therefore, the purpose of this study was to clarify the relationship between basal IS levels and the 1-year outcomes after catheter ablation for the treatment of AF. Our prospective observational study included data from 125 patients with AF who underwent catheter ablation. Over a 1-year follow-up period, AF recurrence was identified in 21 patients. The 1-year AF-free survival was significantly lower in patients with high serum IS levels (≥0.65 μg/mL) than in those with low IS levels (60.1 ± 10.4% versus 85.2 ± 3.9%, P = 0.007). Univariable analysis identified that an IS concentration ≥ 0.65 μg/mL was associated with AF recurrence (hazard ratio [HR] = 3.10 [1.26-7.32], P = 0.015), and this association was maintained in multivariate analysis (HR = 3.67 [1.13-11.7], P = 0.031). Thus, in patients undergoing AF ablation, serum IS levels at baseline independently predict the recurrence of arrhythmia.

Real-time Triggered RAdial Single-Shot Inversion recovery for arrhythmia-insensitive myocardial T1 mapping: motion phantom validation and in vivo comparison

PURPOSE

Cardiac T₁ mapping has become an increasingly important imaging technique, contributing novel diagnostic options. However, currently utilized methods are often associated with accuracy problems because of heart rate variations and cardiac arrhythmia, limiting their value in clinical routine. This study aimed to introduce an improved arrhythmia-related robust T₁ mapping sequence called RT-TRASSI (real-time Triggered RAdial Single-Shot Inversion recovery).

METHODS

All measurements were performed on a 3.0T whole-body imaging system. A real-time feedback algorithm for arrhythmia detection was implemented into the previously described pulse sequence. A programmable motion phantom was constructed and measurements with different simulated arrhythmias arranged. T₁ mapping accuracy and susceptibility to artifacts were analyzed. In addition, in vivo measurements and comparisons with 3 prevailing T₁ mapping sequences (MOLLI, ShMOLLI, and SASHA) were carried out to investigate the occurrence of artifacts.

RESULTS

In the motion phantom measurements, RT-TRASSI showed excellent agreement with predetermined reference T₁ values. Percentage scattering of the T₁ values ranged from -0.6% to +1.9% in sinus rhythm and -1.0% to +3.1% for high-grade arrhythmias. In vivo, RT-TRASSI showed diagnostic image quality with only 6% of the acquired T₁ maps including image artifacts. In contrast, more than 40% of the T₁ maps acquired with MOLLI, ShMOLLI, or SASHA included motion artifacts.

CONCLUSION

Accuracy issues because of heart rate variability and arrhythmia are a prevailing problem in current cardiac T₁ mapping techniques. With RT-TRASSI, artifacts can be minimized because of the short acquisition time and effective real-time feedback, avoiding potential data acquisition during systolic heart phase.

Postoperative atrial fibrillation after cesarean delivery

Background and Aims

Atrial fibrillation (AF) is the most common arrhythmia seen clinically. Due to the lack of literature and guidelines on maternal AF as a postoperative complication following cesarean delivery (CD), we undertook a study to characterize parturients who developed AF following CD and to evaluate arrhythmia management and outcomes in this patient population.

Methods

After receiving ethics committee approval, a retrospective chart review was performed to determine the incidence, possible risk factors, treatment, and outcome of women who developed AF following CD performed between 2003 and 2012 at New York Methodist Hospital in Brooklyn, New York.

Results

A total of 17,039 CDs were performed at New York Methodist Hospital from 2003 to 2012. Of these, seven parturients developed AF after CD. The incidence of AF following CD in this patient population was 1:2,434 (0.04%). The age range was 26-41 years, with a median of 33 years. All 7 parturients were at term or postterm. Two deliveries were elective and five were emergent. Two of the seven parturients had prior history of paroxysmal AF. One patient was identified as having mitral regurgitation. All seven had low levels of serum magnesium postoperatively. Out of the seven, two parturients had spontaneous conversion to normal sinus rhythm, one required electrical cardioversion and four required pharmacologic cardioversion.

Conclusions

Postoperative AF (POAF) exists as a rare complication in women who undergo CD with an incidence of 0.04% in our patient population. All parturients in our study were noted to have hypomagnesemia in the postoperative period. Occurrence of AF increased length of hospital stay and utilization of hospital resources.

Association of peak atrial longitudinal strain with atrial fibrillation recurrence in patients with chronic lung diseases following radiofrequency ablation

BACKGROUND

Strain was shown associated with atrial fibrillation (AF) recurrence after radiofrequency ablation (RFA), but data on AF patients complicated with chronic lung diseases (CLD) were rare.

AIM

This study was designed to evaluate the relationship of baseline atrial function with AF recurrence in these patients using speckle-tracking echocardiography.

METHODS

Average strain values (median: 2 days before RFA) were calculated for 87 AF patients (Mean age: 61.91 years, male: 71.26%) with CLD undergoing RFA from 2013 to 2014. Of these patients, 25 (28.74%) experienced AF recurrence during a mean follow up of 10.3 months.

RESULTS

Peak right atrial longitudinal strain (R-PALS) was associated with peak left atrial longitudinal strain (L-PALS, Standardised β = 0.45, P < 0.001) in multivariate linear regression. Multivariate Cox regression analysis showed R-PALS was associated with AF recurrence (hazard ratio, 0.86; 95% confidence interval (CI), 0.78-0.96, P = 0.005) in CLD. Patients with R-PALS ≥14.69% had higher AF free rate compared with R-PALS<14.69% using Kaplan-Meier analysis (log-rank, P < 0.001). R-PALS had similar C-index compared to L-PALS (difference: 0.03, 95%CI: -0.06-0.12, P = 0.53) and combined R-PALS and L-PALS (difference: 0.005, 95%CI: -0.04-0.05, P = 0.84) associated with AF recurrence in CLD.

CONCLUSION

R-PALS, L-PALS and combined R-PALS and L-PALS are important factors associated with AF recurrence following RFA in patients with CLD.

Predicting Thromboembolic and Bleeding Event Risk in Patients with Non-Valvular Atrial Fibrillation: A Systematic Review

BACKGROUND

 Atrial fibrillation (AF) is a common cardiac arrhythmia that increases the risk of stroke. Medical therapy for decreasing stroke risk involves anticoagulation, which may increase bleeding risk for certain patients. In determining the optimal therapy for stroke prevention for patients with AF, clinicians use tools with various clinical, imaging and patient characteristics to weigh stroke risk against therapy-associated bleeding risk.

AIM

 This article reviews published literature and summarizes available risk stratification tools for stroke and bleeding prediction in patients with AF.

METHODS

 We searched for English-language studies in PubMed, Embase and the Cochrane Database of Systematic Reviews published between 1 January 2000 and 14 February 2018. Two reviewers screened citations for studies that examined tools for predicting thromboembolic and bleeding risks in patients with AF. Data regarding study design, patient characteristics, interventions, outcomes, quality, and applicability were extracted.

RESULTS

 Sixty-one studies were relevant to predicting thromboembolic risk and 38 to predicting bleeding risk. Data suggest that CHADS₂, CHA₂DS₂-VASc and the age, biomarkers, and clinical history (ABC) risk scores have the best evidence for predicting thromboembolic risk (moderate strength of evidence for limited prediction ability of each score) and that HAS-BLED has the best evidence for predicting bleeding risk (moderate strength of evidence).

LIMITATIONS

 Studies were heterogeneous in methodology and populations of interest, setting, interventions and outcomes analysed.

CONCLUSION

 CHADS₂, CHA₂DS₂-VASc and ABC scores have the best prediction for stroke events, and HAS-BLED provides the best prediction for bleeding risk. Future studies should define the role of imaging tools and biomarkers in enhancing the accuracy of risk prediction tools.

PRIMARY FUNDING SOURCE

 Patient-Centered Outcomes Research Institute (PROSPERO #CRD42017069999).

Delayed diagnosis of atrial fibrillation after first-ever stroke increases recurrent stroke risk: a 5-year nationwide follow-up study

BACKGROUND

Delayed detection of atrial fibrillation (AF) is common in patients with stroke. However, it is not well known whether delayed identification of AF in patients with stroke affects the prognosis of patients.

AIMS

To evaluate the association between the timing of AF diagnosis after stroke and clinical outcomes.

METHODS

We identified a cohort of all patients admitted with a primary diagnosis of first-ever ischaemic stroke, which was categorised into three groups, namely, non-AF, AF presenting with stroke and delayed AF diagnosis groups. The study patients were individually followed for 5 years to evaluate the occurrence of recurrent stroke and death.

RESULTS

In total, 17 399 patients were hospitalised with first-ever ischemic stroke, of whom 16 261 constituted the non-AF group, 907 the AF presenting with stroke group and 231 the delayed AF diagnosis group. During the 5-year follow up, 2773 (17.1%), 175 (19.3%) and 68 (29.4%) patients in the non-AF, AF presenting with stroke and delayed AF diagnosis groups, respectively, were hospitalised for recurrent stroke. The delayed AF diagnosis group exhibited a 1.57-times higher risk of recurrent stroke than the AF presenting with stroke group, after adjustment for the CHA2DS2-VASc scores (adjusted hazard ratio (HR): 1.57; 95% confidence interval (CI) = 1.19-2.08; P = 0.002). In addition, delayed diagnosis of AF significantly increased the risk of recurrent stroke in men, but not in women, after adjustment for the CHA2DS2-VASc scores.

CONCLUSION

Delayed diagnosis of AF after stroke increased the risk of recurrent stroke, particularly in men.

Association between P-selectin levels and left atrial blood stasis in patients with nonvalvular atrial fibrillation

BACKGROUND

P-selectin - a biomarker of platelet and endothelial cell activation is elevated in patients with non-valvular atrial fibrillation (NVAF). However, the association between sP-selectin level and thromboembolic complications in NVAF patients remains controversial. We tested the hypothesis that plasma soluble P-selectin (sPSL) level correlates with the measures of left atrial blood stasis in NVAF.

METHODS

Plasma sPSL concentration was measured using solid-phase ELISA in 103 NVAF patients (age 63 ± 14 years; 26% women) and 48 normal sinus rhythm controls (NSR; age 64 ± 14 years; 41% women) who were not on aspirin. Within the group of NVAF cases, 27 had no spontaneous echocardiographic contrast (SEC) detected by transesophageal echocardiography, 31had mild SEC, 15 moderate, 20 severe, and 10 patients had left atrial appendage thrombus (LAAT).

RESULTS

The median soluble sPSL level was higher in NVAF cases compared to NSR controls [(interquartile range) 26 (20-32) ng/mL vs 22 (15-29) ng/mL, p = 0.0045]. Only NVAF patients with CHA₂DS₂-VASc score ≥ 1 had higher sPSL level compared to NSR controls. Patients with severe SEC had significantly higher sPSL levels [32 (24-38) ng/mL] compared to all other NVAF patients (p = 0.0042) and to NSR controls (p < 0.0001). Also NVAF patients with LAAT had higher sPSL level compared to NSR controls.

CONCLUSIONS

There is a direct correlation between p-selectin level and severe blood stasis in the left atrium. Only NVAF patients with CHA₂DS₂-VASc score ≥ 1 or with LAAT had higher sPSL level compared to NSR controls.

Risk of Malignant Cancer Among Women With New-Onset Atrial Fibrillation

IMPORTANCE

A substantial proportion of patients with atrial fibrillation (AF) die of noncardiovascular causes, and recent studies suggest a link between AF and cancer.

OBJECTIVE

To evaluate the associations between AF and cancer in a large, long-term prospective cohort study.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study, a total of 34 691 women 45 years or older and free of AF, cardiovascular disease, and cancer at baseline were prospectively followed up between 1993 and 2013, for incident AF and malignant cancer within the Women's Health Study, a randomized clinical trial of aspirin and vitamin E for the prevention of cardiovascular disease and cancer. Cox proportional hazards models using time-updated covariates were constructed to assess the association of new-onset AF with subsequent cancer and to adjust for potential confounders. Data analysis was performed from December 2014 to May 2015.

EXPOSURE

New-onset AF.

MAIN OUTCOMES AND MEASURES

Incident malignant cancer confirmed by an end point committee.

RESULTS

During a median follow-up of 19.1 years of 34 691 study participants (interquartile range [IQR], 17.6-19.7 years), new-onset AF and malignant cancer were confirmed among 1467 (4.2%) and 5130 (14.8%) participants, respectively. Median age at baseline among participants with new-onset AF and new-onset cancer during follow-up was 58 years (IQR, 52-64 years) and 55 years (IQR, 50-61 years), respectively. Atrial fibrillation was a significant risk factor for incident cancer in age-adjusted (hazard ratio [HR], 1.58; 95% CI, 1.34-1.87; P < .001) and multivariable-adjusted (HR, 1.48; 95% CI, 1.25-1.75; P < .001) models. The relative risk of cancer was highest in the first 3 months after new-onset AF (HR, 3.54; 95% CI, 2.05-6.10; P < .001) but remained significant beyond 1 year after new-onset AF (adjusted HR, 1.42; 95% CI, 1.18-1.71; P < .001), and a trend toward an increased cancer mortality was observed (adjusted HR, 1.32; 95% CI, 0.98-1.79; P = .07). In contrast, among women with new-onset cancer, the relative risk of AF was increased only within the first 3 months (HR, 4.67; 95% CI, 2.85-7.64; P < .001) but not thereafter (HR, 1.15; 95% CI, 0.95-1.39; P = .15).

CONCLUSIONS AND RELEVANCE

In this large, initially healthy cohort, women with new-onset AF had an elevated cancer risk beyond 1 year of AF diagnosis. Shared risk factors and/or common systemic disease processes might underlie this association.

Predictors of new oral anticoagulant drug initiation as opposed to warfarin in elderly adults: a retrospective observational study in Southern Italy

AIM

The aim of this study was to assess the predictive role of age, gender, and number and type of co-treatments for new oral anticoagulant (NOAC) vs warfarin prescription in elderly patients naïve for the aforementioned drugs.

MATERIALS AND METHODS

Data collected in the period from January 1, 2014, to December 31, 2014, in Caserta Local Health Unit administrative databases (Campania Region, Italy) were screened to identify new users of oral anticoagulants (OACs) who were 75 years or older and whose OAC prescriptions amounted to >90 days of treatment. Age, gender, and number and type of concomitant medications at the time of first OAC dispensation were retrieved. Multivariable logistic regression analysis was used to assess the role of the aforementioned predictors for NOAC initiation as opposed to warfarin.

RESULTS

Overall, 2,132 incident users of OAC were identified, of whom 967 met all inclusion criteria. In all, 490 subjects (50.7%) received an NOAC and 477 (49.3%) received warfarin. Age >75 years was positively associated with lower odds of NOAC initiation (OR: 0.969, 95% CI: 0.941-0.998, P=0.038). Similarly, multiple concomitant medication was negatively associated with NOAC initiation compared to warfarin (OR [five to nine drugs] group: 0.607, 95% CI: 0.432-0.852, P=0.004; OR [ten+ drugs] group: 0.372, 95% CI: 0.244-0.567, P<0.001). Prior exposure to platelet aggregation inhibitor drugs was associated with the initiation of NOACs (OR: 3.474, 95% CI: 2.610-4.625).

CONCLUSION

Age and multiple co-medication were negatively associated with NOAC initiation.

Dynamic Electrocardiography is Useful in the Diagnosis of Persistent Atrial Fibrillation Accompanied with Second-Degree Atrioventricular Block

BACKGROUND

Periodic electrocardiography (ECG) at every clinical visit is generally performed for heart rhythm surveillance, and 24-h Holter ECG is usually used as the gold standard. We aimed to investigate the electrocardiographic features of persistent atrial fibrillation (AF) accompanied with second-degree atrioventricular block (AVB).

METHODS

From October 2012 to November 2015, 204 patients with an RR interval > 2.0 s before radiofrequency ablation were included. Dynamic ECG (DCG) was performed before and after the radiofrequency ablation. The patients were divided into two groups based on changes in DCG after radiofrequency ablation: group A (non-second-degree AVB group) and group B (second-degree AVB group). An RR interval > 2.0 s, the distribution of escape rhythm, mean heart rate and the long RR interval in the two groups were analyzed.

RESULTS

After radiofrequency ablation, all 204 patients who had persistent AF converted to sinus rhythm successfully. In group A (n = 193), the distribution of an RR interval > 2.0 s and escape rhythm were significantly correlated with sleep or rest, while no correlation was observed in group B (n = 11). The average RR interval prolongation and escape rhythm were significantly higher in group B than in group A (p < 0.05). The average number of long RR intervals > 3.0 s and average number of escape rhythm episodes (< 35 bpm) were significant predictive factors of second-degree AVB after radiofrequency ablation.

CONCLUSIONS

DCG is a useful tool for the diagnosis of persistent AF accompanied with second-degree AVB.

Risk of intracranial hemorrhage (RICH) in users of oral antithrombotic drugs: Nationwide pharmacoepidemiological study

Background

The risks of intracranial haemorrhage (ICH) associated with antithrombotic drugs outside clinical trials are gaining increased attention. The aim of this nationwide study was to investigate the risk of ICH requiring hospital admission in users of antithrombotic drugs.

Methods and findings

Data from the Norwegian Patient Registry and Norwegian Prescription Database were linked on an individual level. The primary outcome was incidence rates of ICH associated with use of antithrombotic drugs. Secondary endpoints were risk of ICH and fatal outcome following ICH assessed by Cox models. Among 3,131,270 individuals ≥18 years old observed from 2008 through 2014, there were 729,818 users of antithrombotic medications and 22,111 ICH hospitalizations. Annual crude ICH rates per 100 person-years were 0.076 (95% CI, 0.075–0.077) in non-users and 0.30 (95% CI, 0.30–0.31) in users of antithrombotic medication, with the highest age and sex adjusted rates observed for aspirin-dipyridamole plus clopidogrel (0.44; 95% CI, 0.19–0.69), rivaroxaban plus aspirin (0.36; 95% CI, 0.16–0.56), warfarin plus aspirin (0.34; 95% CI, 0.26–0.43), and warfarin plus aspirin and clopidogrel (0.33; 95% CI, 0.073–0.60). With no antithrombotic medication as reference, the highest adjusted hazard ratios (HR) for ICH were observed for aspirin-dypiridamole plus clopidogrel (6.29; 95% CI 3.71–10.7), warfarin plus aspirin and clopidogrel (4.38; 95% CI 2.71–7.09), rivaroxaban plus aspirin (3.82; 95% CI, 2.46–5.95), and warfarin plus aspirin (3.40; 95% CI, 2.99–3.86). All antithrombotic medication regimens were associated with an increased risk of ICH, except dabigatran monotherapy (HR 1.20; 95% CI, 0.88–1.65) and dabigatran plus aspirin (HR 1.79; 95% CI, 0.96–3.34). Fatal outcome within 90 days was more common in users (2,603 of 8,055) than non-users (3,228 of 14,056) of antithrombotic medication (32.3% vs 23.0%, p<0.001), and was associated with use of warfarin plus aspirin and clopidogrel (HR 2.89; 95% CI, 1.49–5.60), warfarin plus aspirin (HR 1.37; 95% CI, 1.11–1.68), aspirin plus clopidogrel (HR 1.30; 95% CI, 1.05–1.61), and warfarin (HR 1.19; 95% CI, 1.09–1.31). Increased one-year mortality was observed in users of antithrombotic medication following hemorrhagic stroke, subdural hemorrhage, subarachnoid hemorrhage, and traumatic ICH (all p<0.001). Limitations include those inherent to observational studies including the inability to make causal inferences, certain assumptions regarding drug exposure, and the possibility of residual confounding.

Conclusions

The real-world incidence rates and risks of ICH were generally higher than reported in randomized controlled trials. There is still major room for improvement in terms of antithrombotic medication safety (clinicaltrials.gov NCT02481011).

Role of the CHADS2 Score in the Evaluation of Carotid Atherosclerosis in Patients with Atrial Fibrillation Undergoing Carotid Artery Ultrasonography

Objective

This study investigated the characteristics of carotid atherosclerosis in patients with atrial fibrillation (AF) and determined the feasibility and significance of the CHADS₂ score in predicting the degree of carotid atherosclerosis.

Methods

Consecutive patients (n = 109) with nonvalvular AF were registered and classified into two groups, the paroxysmal AF group (n = 59) and persistent AF group (n = 50). Fifty healthy patients, matched by sex and age, were considered the control group. All patients were examined using carotid ultrasound and velocity vector imaging (VVI).

Results

Compared with the control group, the mean intimal-medial thickness in the paroxysmal AF group (0.56 ± 0.11 versus 0.61 ± 0.10, respectively, P < 0.05) and the persistent AF group (0.56 ± 0.11 versus 0.64 ± 0.13, respectively, P < 0.001) was significantly increased. The plaque index (PI) in the persistent AF group was significantly higher than that observed in the paroxysmal AF group (1.05 ± 1.33 versus 1.42 ± 1.47, respectively, P < 0.001). Regarding the VVI indices, those reflecting the long-axis longitudinal motion function of carotid arteries were significantly decreased in both AF groups. Compared with the control group, a significantly lower total longitudinal displacement (tLoD) index was observed in the persistent AF group (0.73 ± 0.66 versus 0.31 ± 0.23, respectively, P < 0·0001) and the paroxysmal AF group (0.73 ± 0.66 versus 0.34 ± 0.17, P < 0·0001). The CHADS₂ score was related to indicators reflecting the structure and function of the carotid artery.

Conclusions

Carotid arterial structure and function were significantly altered in patients with AF. The degree of carotid atherosclerosis depended on the duration of AF. The CHADS₂ score may be useful as a predictor of the extent of carotid atherosclerosis in patients with AF.

Reference effect measures for quantifying, comparing and visualizing variation from random and fixed effects in non-normal multilevel models, with applications to site variation in medical procedure use and outcomes

BACKGROUND

Multilevel models for non-normal outcomes are widely used in medical and health sciences research. While methods for interpreting fixed effects are well-developed, methods to quantify and interpret random cluster variation and compare it with other sources of variation are less established. Random cluster variation, sometimes referred to as general contextual effects (GCE), may be the main focus of a study; therefore, easily interpretable methods are needed to quantify GCE. We propose a Reference Effect Measure (REM) approach to 1) quantify GCE and compare it to individual subject and cluster covariate effects, and 2) quantify relative magnitudes of GCE and variation from sets of measured factors.

METHODS

To illustrate REM, we consider a two-level mixed logistic model with patients clustered within hospitals and a random intercept for hospitals. We compare patients at hospitals at given percentiles of the estimated random effect distribution to patients at a median or 'reference' hospital. These estimates are then compared numerically and graphically to individual fixed effects to quantify GCE in the context of effects of other measured variables (aim 1). We then extend this approach by comparing variation from the random effect distribution to variation from sets of fixed effects to understand their magnitudes relative to overall outcome variation (aim 2).

RESULTS

Using an example of initiation of rhythm control treatment in atrial fibrillation (AF) patients within the Veterans Affairs (VA), we use REM to demonstrate that random variation across hospitals (GCE) in initiation of treatment is substantially greater than that due to most individual patient factors, and explains at least as much variation in treatment initiation as do all patient factors combined. These results are contrasted with a relatively small GCE compared with patient factors in 1 year mortality following hospitalization for AF patients.

CONCLUSIONS

REM provides a means of quantifying random effect variation (GCE) with multilevel data and can be used to explore drivers of outcome variation. This method is easily interpretable and can be presented visually. REM offers a simple, interpretable approach for evaluating questions of growing importance in the study of health care systems.

Risk analysis of new oral anticoagulants for gastrointestinal bleeding and intracranial hemorrhage in atrial fibrillation patients: a systematic review and network meta-analysis

BACKGROUND

Antithrombotic therapy using new oral anticoagulants (NOACs) in patients with atrial fibrillation (AF) has been generally shown to have a favorable risk-benefit profile. Since there has been dispute about the risks of gastrointestinal bleeding (GIB) and intracranial hemorrhage (ICH), we sought to conduct a systematic review and network meta-analysis using Bayesian inference to analyze the risks of GIB and ICH in AF patients taking NOACs.

METHODS

We analyzed data from 20 randomized controlled trials of 91 671 AF patients receiving anticoagulants, antiplatelet drugs, or placebo. Bayesian network meta-analysis of two different evidence networks was performed using a binomial likelihood model, based on a network in which different agents (and doses) were treated as separate nodes. Odds ratios (ORs) and 95% confidence intervals (CIs) were modeled using Markov chain Monte Carlo methods.

RESULTS

Indirect comparisons with the Bayesian model confirmed that aspirin+clopidogrel significantly increased the risk of GIB in AF patients compared to the placebo (OR 0.33, 95% CI 0.01-0.92). Warfarin was identified as greatly increasing the risk of ICH compared to edoxaban 30 mg (OR 3.42, 95% CI 1.22-7.24) and dabigatran 110 mg (OR 3.56, 95% CI 1.10-8.45). We further ranked the NOACs for the lowest risk of GIB (apixaban 5 mg) and ICH (apixaban 5 mg, dabigatran 110 mg, and edoxaban 30 mg).

CONCLUSIONS

Bayesian network meta-analysis of treatment of non-valvular AF patients with anticoagulants suggested that NOACs do not increase risks of GIB and/or ICH, compared to each other.

Association Between Blood Lipid Profiles and Atrial Fibrillation: A Case-Control Study

Background

Dyslipidemia is the most frequent comorbidity in patients with cardiovascular disease. However, studies examining the relationship between blood lipid profiles and AF have produced inconsistent results.

Material/Methods

A total of 651 patients were enrolled into 3 groups: Healthy controls (n=64), Paroxysmal AF (PAF; n=270), and Continuous AF (CAF; n=317). All enrolled patients underwent routine baseline 12-lead electrocardiography (ECG) and 24-h dynamic ECG along with blood testing, which included the following: complete metabolic panel, hepatic function, renal function, circulating thyroxine, fasting high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and total cholesterol (TC).

Results

Patients with AF had significantly higher levels of triglycerides (TG), lower levels of LDL-C-c, and lower levels of HDL-C (p<0.05). TC (OR 0.979, p<0.9247) and TG (OR 0.945, p<0.6496) were negatively and linearly associated with PAF, while TG (OR 0.807, p=0.2042), LDL-C (OR 0.334, p=0.0036), and HDL-C (OR 0.136, p=0.0002) were negatively and linearly associated with CAF.

Conclusions

Compared to healthy controls, patients with AF had lower blood lipid levels, especially LDL-c and HDL-c levels. Hypolipoproteinemia may increase patient susceptibility to developing AF.

Therapeutic Strategies Following Major, Clinically Relevant Nonmajor, and Nuisance Bleeding in Atrial Fibrillation: Findings From ORBIT-AF

Background

Oral anticoagulation (OAC) reduces stroke risk in atrial fibrillation, but bleeding is a frequent side effect. The decision to discontinue or modify medication regimens in response to a bleeding event may differ according to bleeding site and severity.

Methods and Results

We used data from a large, national outpatient registry, ORBIT‐AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation; 2010–2011), to evaluate event characteristics and OAC management following the first bleeding event occurring during follow‐up. Bleeding events were classified into 3 categories: (1) International Society of Thrombosis and Hemostasis major bleeding, (2) clinically relevant nonmajor bleeding requiring medical attention, and (3) nuisance bleeding not requiring medical attention (eg, bruising, hemorrhoidal bleeding). Of 9743 patients enrolled in ORBIT‐AF with follow‐up data, 510 (3.23/100 subject‐years) experienced a major bleed, 615 (3.90/100 subject‐years), experienced a clinically relevant nonmajor bleed, and 1558 (9.87/100 subject‐years) experienced a nuisance bleed, among first bleeds over 2 years. Nearly one third of patients (31.6%) discontinued OAC therapy following a major bleeding event, 12.7% following a clinically relevant nonmajor bleed, and 4.5% following a nuisance bleed. Compared with those who experienced a clinically relevant nonmajor or nuisance bleed, patients who experienced a major bleed were more likely to be black and female and to have a history of heart failure and stroke. Those who discontinued were more likely to have central nervous system or gastrointestinal bleeding than those who persisted on OAC therapy.

Conclusions

Overall, 1 in 3 patients who experienced a major bleed was no longer anticoagulated after the event. Those who discontinued OAC were more likely to have central nervous system or gastrointestinal bleeding than those who persisted on OAC.

Catheter Ablation versus Antiarrhythmic Drug Therapy for Atrial Fibrillation (CABANA) Trial: Study Rationale and Design

The Catheter Ablation Versus Anti-arrhythmic Drug Therapy for Atrial Fibrillation (CABANA, NCT00911508)(1) trial is testing the hypothesis that the treatment strategy of percutaneous left atrial catheter ablation for the purpose of eliminating atrial fibrillation (AF) is superior to current state-of-the-art pharmacologic therapy. This international 140-center clinical trial was designed to randomize 2200 patients to a strategy of catheter ablation versus state-of-the-art rate or rhythm control drug therapy. Inclusion criteria include: 1) age > 65, or ≤65 with≥ 1 risk factor for stroke, 2) documented AF warranting treatment, and 3) eligibility for both catheter ablation and≥ 2 anti-arrhythmic or≥ 2 rate control drugs. Patients were followed every 3 to 6 months (median 4 years) and underwent repeat trans-telephonic monitoring, Holter monitoring, and CT/MR in a subgroup of patient studies to assess the impact of treatment on AF recurrence and atrial structure.

With 1100 patients in each treatment arm, CABANA is projected to have 90% power for detecting a 30% relative reduction in the primary composite endpoint of total mortality, disabling stroke, serious bleeding, or cardiac arrest. Secondary endpoints include total mortality; mortality or cardiovascular hospitalization; a combination of mortality, stroke, hospitalization for heart failure or acute coronary artery events; cardiovascular death alone; and heart failure death, as well as AF recurrence, quality of life, and cost effectiveness. At a time when AF incidence is rising rapidly, CABANA will provide critical evidence with which to guide therapy and shape health care policy related to AF for years to come.

Tailored Anticoagulation for Thromboembolic Risk Reduction in Paroxysmal Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting up to six million people in the United States and more than 35 million individuals worldwide. Thromboembolism, including stroke, represents the most common AF-related morbidity and mortality and data indicate that anticoagulation can mitigate this risk by 65%. Our understanding of thromboembolism in AF, however, remains incomplete, and the mechanisms by which AF increases thromboembolic risk are areas of ongoing investigation and debate. Current guidelines do not differentiate between the frequency and duration of AF episodes (AF burden) when selecting which patients with AF should be treated with anticoagulation for thromboembolic risk reduction. Recent data, primarily using cardiac implantable electronic devices (CIEDs) such as pacemakers, implantable cardioverter-defibrillators, and implantable loop recorders, however, have challenged this longstanding notion that AF burden does not influence thromboembolic risk. Continuous and automated cardiac rhythm monitoring via CIEDs with accurate and rapid acquisition and transmission of rhythm data also affords the opportunity to study the relationship between AF burden and thromboembolism and novel ways to reduce thromboembolic risk while minimizing the risk associated with chronic anticoagulation use. This manuscript will review the associations between subclinical, CIED-detected atrial arrhythmias and thromboembolic events. It will also discuss the emergence of "tailored anticoagulation," an anticoagulation strategy wherein CIEDs and remote AF monitoring are employed to allow dynamic administration of oral anticoagulation only around episodes of AF, and the holding of anticoagulation during prolonged periods of sinus rhythm when the thromboembolic risk associated with AF is presumably very low.

Mineralocorticoid Receptor Antagonism in Patients With Atrial Fibrillation: Findings From the ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) Registry

Background

Mineralocorticoid receptor antagonist (MRA) therapy may be beneficial to patients with atrial fibrillation (AF), but little is known about their use in patients with AF and subsequent outcomes.

Methods and Results

In order to better understand MRA use and subsequent outcomes, we performed a retrospective cohort study of the contemporary ORBIT‐AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) registry. AF progression and cardiovascular outcomes were compared using propensity‐matched Cox proportional hazards modeling according to MRA use at baseline and new MRA use at follow‐up versus patients with no MRA use. Among 7012 patients with nonpermanent AF, 320 patients were taking MRA at enrollment, and 416 patients initiated MRA use during follow‐up. The mean patient age was 72.5 years, 56.3% were men, and 70.4% had paroxysmal AF. Among all patients taking MRAs, 434 (59.0%) had heart failure, 655 (89.0%) had hypertension, and 380 (51.6%) had both. After adjustment, new MRA use was not associated with reduced AF progression (hazard ratio, 1.18; 95% confidence interval, 0.88–1.58; P=0.27) but showed a trend towards lower risk of stroke, transient ischemic attack, or systemic embolism (hazard ratio, 0.17; 95% confidence interval, 0.02–1.23; P=0.08). Results were similar for a comparison of new MRA users and baseline MRA users compared with nonusers.

Conclusions

In community‐based outpatients with AF, the majority of MRA use was for heart failure and hypertension. MRA use also trended towards lower adjusted stroke risk. Future studies should test the hypothesis that MRA use may decrease the risk of stroke in patients with AF.

Impact of known or new-onset atrial fibrillation on 2-year cardiovascular event rate in patients with acute coronary syndromes: results from the prospective EPICOR Registry

Background:

Atrial fibrillation (AF) is associated with increased morbidity in acute coronary syndrome patients, but impact on outcomes beyond 1 year is unclear.

Methods:

This was a post-hoc analysis from the long-tErm follow-uP of antithrombotic management patterns In acute CORonary syndrome patients (EPICOR) registry (NCT01171404), a prospective, observational study conducted in Europe and Latin America, which enrolled acute coronary syndrome survivors at discharge. Antithrombotic management patterns, mortality, a composite endpoint of death/new non-fatal myocardial infarction/stroke and bleeding events were assessed after 2 years of follow-up in patients with or without AF.

Results:

Of 10,568 patients enrolled, 397 (4.7%) had prior AF and 382 (3.6%) new-onset AF during index hospitalisation. Fewer patients with AF underwent percutaneous coronary intervention (52.1% vs. 66.6%; P<0.0001). At discharge, fewer AF patients received dual antiplatelet therapy (71.6% vs. 89.5%; P<0.0001); oral anticoagulant use was higher in AF patients but was still infrequent (35.0% vs. 2.5%; P<0.0001). Use of dual antiplatelet therapy and oral anticoagulants declined over follow-up with over 50% of all AF/no AF patients remaining on dual antiplatelet therapy (55.6% vs. 60.6%), and 23.3% (new-onset AF) to 42.1% (prior AF) on oral anticoagulants at 2 years. At 2 years, mortality, composite endpoint and bleeding rates were higher in AF patients (all P<0.0001) compared to patients without AF. On multivariable analysis, the risk of mortality or the composite endpoint was significant for prior AF ( P=0.003, P=0.001) but not new-onset AF ( P=0.88, P=0.92).

Conclusions:

Acute coronary syndrome patients with AF represent a high-risk group with increased event rates during long-term follow-up. Prior AF is an independent predictor of mortality and/or ischaemic events at 2 years. Use of anticoagulants in AF after acute coronary syndrome is still suboptimal.

Trends in warfarin use and its associations with thromboembolic and bleeding rates in a population with atrial fibrillation between 1996 and 2011

AIM

Warfarin is a cornerstone for the prevention of thromboembolism in atrial fibrillation (AF), and several efforts have been taken to increase its usage and safety, including risk stratification schemes. Our aim was to investigate the temporal trends in initiation of warfarin and its effects on incidence of bleeding and thromboembolism in patients with new-onset atrial fibrillation 1996-2011.

METHODS

All patients with a first-time diagnosis of non-valvular atrial fibrillation were identified from nationwide administrative registries. Trends were determined by linear regression.

RESULTS

In total 153,682 patients were included. Initiation of warfarin increased from 14% to 41% (p<0.0001). Events of thromboembolism decreased from 3.9% to 2.6% annually (p<0.0001). The greatest decline in thromboembolic events was observed for patients with a CHA2DS2VASc score >1, where the annual decline was -0.12% (95%CI: -0.161; -0.084)) for those treated with warfarin and -0.073% (95%CI: -0.116;-0.030)) for those not treated with warfarin. Bleeding increased from 3.3% to 3.9% (p = 0.043). For those with a CHA2DS2VASc score >1 annual bleeding rates increased by 0.095% (95%CI: -0.025; -0.165) in warfarin treated and by 0.056% (95%CI: -0.013; -0.100) in patients not treated with warfarin.

CONCLUSION

Warfarin use increased by nearly a 3-fold between 1996 and 2011. During the same period, thromboembolic events declined by a third and bleeding increased by a fifth, suggesting a beneficial effect associated with higher warfarin use. Notably, a small decline in thromboembolic events and increase in bleeding events was observed for the untreated population, suggesting a changing risk profile of AF patients.

Is Appropriate Management of Atrial Fibrillation in Primary Care a Utopia?

Objective:

The authors aimed at reporting on whether or not primary care doctors follow atrial fibrillation (AF) treatment protocols, and on the mental distress of such patients.

Methods:

A total of 138 patients with first detected or recurrent AF were examined in a health center. Demographic data were collected and their lifestyle and medical history for rhythm-related pathologies and chronic medication were investigated. Physical examination, electrocardiogram (EKG), and in selected cases, lab analysis were carried-out. CHADS2 index was used for assessing the stroke risk in patients with AF, while the General Health Questionnaire-12 (GHQ-12) for personal health perception was performed in all patients.

Results:

According to CHADS2 the majority of the patients had at least 1 risk factor and half of those receiving oral vitamin K antagonists presented an out-of-range international normalized ratio (INR). In 24 cases, patients used both aspirin and oral anticoagulants, while in 41 cases, medication was corrected according to index. GHQ-12 seemed to be significantly worse in paroxysmal and persistent cases, as well as in women with recurrent AF. Many paroxysmal AF patients under 75 years continued caffeine intake, whereas an extensive use of benzodiazepines was noticed in the majority of patients.

Conclusions:

Shortages and limitations of the peripheral or rural units and health centers and inadequate knowledge and application of the guidelines, seemed to be major factors responsible for mismanaging AF patients. More education in prehospital cardiology may contribute in improving management of arrhythmias in primary care.

Localizing the Accessory Pathway in Ventricular Preexcitation Patients Using a Score Based Algorithm

Objectives: Clinical data was analyzed to find an efficient way to localize the accessory pathway in patients with ventricular preexcitation.

Methods: The delta wave morphologies and ablation sites of 186 patients who underwent catheter ablation were analyzed and an algorithm (“locAP”) to localize the accessory pathway was developed from the 84 data sets with a PQ interval ≤ 0.12 s and a QRS width ≥ 0.12 s. Fifty additional patients were included for a prospective validation. The locAP algorithm ranks 13 locations according to the likelihood that the accessory pathway is localized there. The algorithm is based on the locAP score which uses the standardized residuals of the available data sets.

Results: The locAP algorithm’s accuracy is 0.54 for 13 locations, with a sensitivity of 0.84, a specificity of 0.97, and a positive likelihood ratio of 24.94. If the two most likely locations are regarded, the accuracy rises to 0.79, for the three most likely locations combined the accuracy is 0.82. This new algorithm performs better than Milstein’s, Fitzpatrick’s, and Arruda’s algorithm both in the original study population as well as in a prospective study.

Conclusions: The locAP algorithm is a valid and valuable tool for clinical practice in a cardiac electrophysiology laboratory. It could be shown that use of the locAP algorithm is favorable over the localizing algorithms that are in clinical use today.