Atrial Fibrillation Pattern Research Articles

Reappraisal of Atrial fibrillation: interaction between hyperCoagulability, Electrical remodelling and Vascular destabilisation in the progression of AF (RACEV) Tissue Bank Project: study design.

BackgroundThe development of atrial fibrillation (AF) is a complex multifactorial process. Over the past few decades, much has been learned about the pathophysiological processes that can lead to AF from a variety of specific disease models in animals. However, our ability to recognise these disease processes in AF patients is still limited, which has contributed to the limited progress in improving rhythm control in AF.Aims/objectivesWe believe that a better understanding and detection of the individual pathophysiological mechanisms underlying AF is a prerequisite for developing patient-tailored therapies. The RACE V Tissue Bank Project will contribute to the unravelling of the main molecular mechanisms of AF by studying histology and genome-wide RNA expression profiles and combining this information with detailed phenotyping of patients undergoing cardiac surgery.MethodsAs more and more evidence suggests that AF may occur not only during the first days but also during the months and years after surgery, we will systematically study the incidence of AF during the first years after cardiac surgery in patients with or without a history of AF. Both the overall AF burden as well as the pattern of AF episodes will be studied. Lastly, we will study the association between the major molecular mechanisms and the clinical presentation of the patients, including the incidence and pattern of AF during the follow-up period.ConclusionThe RACE V Tissue Bank Project combines deep phenotyping of patients undergoing cardiac surgery, including rhythm follow-up, analysis of molecular mechanisms, histological analysis and genome-wide RNA sequencing. This approach will provide detailed insights into the main pathological alterations associated with AF in atrial tissue and thereby contribute to the development of individualised, mechanistically informed patient-tailored treatment for AF.

Novel Density Poincaré Plot Based Machine Learning Method to Detect Atrial Fibrillation From Premature Atrial/Ventricular Contractions.

Detection of Atrial fibrillation (AF) from premature atrial contraction (PAC) and premature ventricular contraction (PVC) is difficult as frequent occurrences of these ectopic beats can mimic the typical irregular patterns of AF. In this paper, we present a novel density Poincaré plot-based machine learning method to detect AF from PAC/PVCs using electrocardiogram (ECG) recordings. First, we propose the generation of this new density Poincaré plot which is derived from the difference of the heart rate (DHR) and provides the overlapping phase-space trajectory information of the DHR. Next, from this density Poincaré plot, several image processing domain-based approaches including statistical central moments, template correlation, Zernike moment, discrete wavelet transform and Hough transform features are used to extract suitable features. Subsequently, the infinite latent feature selection algorithm is implemented to rank the features. Finally, classification of AF vs. PAC/PVC is performed using K-Nearest Neighbor, Support vector machine (SVM) and Random Forest (RF) classifiers. Our method is developed and validated using a subset of Medical Information Mart for Intensive Care (MIMIC) III database containing 10 AF and 10 PAC/PVC subjects. Results- During the segment-wise 10-fold cross-validation, SVM achieved the best performance with 98.99% sensitivity, 95.18% specificity and 97.45% accuracy with the extracted features. In subject-wise scenario, RF achieved the highest accuracy of 91.93%. Moreover, we further validated the proposed method using two other databases: wearable armband ECG data and the Physionet AFPDB. 100% PAC detection accuracy was obtained for both databases without any further training. Our proposed density Poincaré plot-based method showed superior performance when compared with four existing algorithms; thus showing the efficacy of the extracted image domain-based features. From intensive care unit's ECG to wearable armband ECGs, the proposed method is shown to discriminate PAC/PVCs from AF with high accuracy.

Circadian Pattern of Acute Myocardial Infarction and Atrial Fibrillation in a Mediterranean Country: A study in Diabetic Patients.

Background and objectives: The circadian pattern seems to play a crucial role in cardiovascular events and arrhythmias. Diabetes mellitus is a complex metabolic disorder associated with autonomic nervous system alterations and increased risk of microvascular and macrovascular disease. We sought to determine whether acute myocardial infarction (AMI) and atrial fibrillation (AF) follow a circadian pattern in diabetic patients in a Mediterranean country. Materials and Methods: This retrospective study included 178 diabetic patients (mean age: 67.7) with AMI or AF who were admitted to the coronary care unit. The circadian pattern of AMI and AF was identified in the 24-h period (divided in 3-h and 1-h intervals). Patients were also divided in 3 groups according to age; 40–65 years, 66–79 years and patients older than 80 years. A chi-square goodness-of-fit test was used for the statistical analysis. Results: AMI seems to occur more often in the midnight hours (21:00–23:59) (p < 0.001). Regarding age distribution, patients between 40 and 65 years were more likely to experience an AMI compared to other age groups (p < 0.001). Autonomic alterations, working habits, and social reasons might contribute to this phenomenon. AF in diabetic patients occurs more frequently at noon (12:00–14:59) (p = 0.019). Conclusions: Diabetic patients with AMI and AF seem to follow a specific circadian pattern in a Mediterranean country, with AMI occurring most often at midnight hours and AF mostly at noon. Autonomic dysfunction, glycemic fluctuations, intense anti-diabetic treatment before lunch, and patterns of insulin secretion and resistance may explain this pattern. More studies are needed to elucidate the circadian pattern of AMI and AF in diabetic patients to contribute to the development of new therapeutic approaches in this setting.

Possible Perioperative Arrhythmias

Atrial fibrillation (AF) is the most common persistent cardiac arrhythmia, and it is predicted that one of four middle-aged adults in developed countries will develop AF. By 2030, 14-17 million patients with AF are expected in the European Union, with 120.000-215.000 newly diagnosed patients per year. AF is independently associated with an increased risk of death and high morbidity, such as heart failure and stroke, but also with frequent hospitalizations and reduced quality of life. AF usually progresses from short, rare paroxysmal episodes to longer and more frequent attacks, culminating as persistent AF. Although the pattern of AF may be the same, the mechanisms that induce AF vary significantly between patients.

Left Atrial Appendage Electrical Isolation Reduces Atrial Fibrillation Recurrences: A Simulation Study.

Left Atrial Appendage Electrical Isolation Reduces Atrial Fibrillation Recurrences: A Simulation Study.

Electrocardiographic imaging including intracardiac information to achieve accurate global mapping during atrial fibrillation

Atrial fibrillation (AF) is characterized by complex and irregular propagation patterns. Noninvasive electrocardiographic imaging (ECGI) has been tested during AF conditions with promising results. However, current regularization methods face important challenges in this type of unstable electrical activity scenarios. Combination of intracardiac and non-invasive simultaneous recordings could improve ECGI performance and allow real-time global mapping of complex AF patterns. In this work, we propose an ECGI method that incorporates intracardiac measurements as a constraint in a reformulation of the classical Tikhonov method. We used realistic mathematical models of atria and torso that simulates a wide number of epicardial electrical activity patterns. Body surface potentials were obtained from simulated electrograms (EGMs) by using Boundary Element Method and corrupted with Gaussian noise. Epicardial potentials were estimated using inverse problem with Tikhonov regularization, including intracavitary information as a second constraint. Results showed that first-order Constrained Tikhonov formulation provided more reliable reconstructions than the classical Tikhonov approach in AF conditions using at least 32 uniformly distributed endocardial EGMs (CC between 0.87 and 0.28, depending on the AF complexity). Constrained Tikhonov provided more accurate spatial mass functions (SMF) of PS locations (CCSMF between 0.24 and 0.86). This methodology was tested on real patient data, obtaining a mean DF RMSE of 0.85 Hz, outperforming the classical Tikhonov approach. Limitations of this study include the fact that the model considered endocardium and epicardium as a single layer. Further research will include endocardium–epicardium bilayer model approximations and validation using more real patient data.

Atrial fibrillation pattern, left atrial diameter and risk of cardiovascular events and mortality. A prospective multicenter cohort study.

There are conflicting evidence on the association between atrial fibrillation (AF) pattern, such as persistent/permanent (Pers/Perm) and paroxysmal (PAF) AF and risk of ischemic events. We investigated if left atrial diameter (LAd) may affect the risk of cardiovascular outcomes according to AF pattern. Prospective multicenter observational including 1,252 non-valvular AF patients (533 PAF and 719 Pers/Perm AF). Study endpoints were cardiovascular events (CVEs), major adverse cardiac events (MACE) and CV death. LA anteroposterior diameter (LAd) was obtained by transthoracic echocardiography. Pers/Perm AF patients had a higher proportion of LAd above median than PAF (≥44mm, 59.5% vs 37.5% respectively, P<.001). In a mean follow-up of 42.2±31.0months (4,315 patients/year) 179 CVEs (incidence rate [IR] 4.2%/year), 133 MACE (IR 3.1%/year), and 97 CV deaths (IR 2.2%/year) occurred. Compared to patients with LAd below median, those with LAd above the median had a higher rate of CVEs (log-rank test, P<.001), MACE (log-rank test P<.001), and CV death (log-rank test P<.001). Multivariable Cox regression analysis showed that LAd above the median was associated with CVEs, (HR 1.569, 95% CI 1.129-2.180, P=.007) MACE (HR 1.858, 95% CI 1.257-2.745, P=.002) and CV death (HR 2.106, 95% CI 1.308-3.390, P=.002). The association between LAd and outcomes was evident both in PAF and Pers/Perm AF patients. No association between AF pattern and outcomes was found. LAd is a simple parameter that can be obtained in virtually all AF patients and can provide prognostic information on the risk of CVEs, MACE and CV death regardless of AF pattern.

Incidence, duration, pattern, and burden of de novo atrial arrhythmias detected by continuous ECG monitoring using an implantable loop recorder following ablation of the cavotricuspid isthmus

BackgroundFollowing cavotricuspid isthmus (CTI) ablation, many patients with atrial flutter (AFL) are diagnosed with atrial fibrillation (AF). The incidence, duration, pattern, and burden of AF remain undefined. These may have implications for the management of these patients.ObjectiveTo classify the incidence, duration, pattern, and burden of AF/AFL using an implantable loop recorder (ILR) after CTI ablation.MethodsWe enrolled consecutive patients with CTI-dependent AFL, no known history of AF, and CHA2DS2-VASc ≥ 2. An ILR was implanted before or within 90 days of ablation. The time to first AF/AFL, pattern, duration, and burden of longest AF/AFL were determined. Five distinct AF/AFL cohorts were identified: no AF/AFL and those with recurrences of isolated, clustered, frequent, or persistent AF/AFL.ResultsFifty-two patients (81% male; 73 ± 9 years; CHA2DS2-VASc 3.7 ± 1.2) were followed for 784 (interquartile range [IQR] 263, 1150) days. AF/AFL occurred in 44 (85%) patients at 64 (IQR 8, 189) days post-CTI ablation and was paroxysmal in 31 (70%) patients (burden 0.6% [IQR 0.1, 4.8]). AF/AFL was isolated (n = 5, 11%), clustered (n =7, 16%), frequent (n =19, 43%), and persistent (n =13, 30%). The longest AF episode was <24 hours in 27 (61%) patients.ConclusionFollowing CTI ablation in AFL patients, although AF/AFL occurs in most patients, the burden is low and episodes were <24 hours in the majority of patients. Additional studies are needed to determine whether long-term electrocardiographic monitoring can help guide management of patients undergoing CTI ablation.

Magnetic resonance-guided re-ablation for atrial fibrillation is associated with a lower recurrence rate: a case-control study.

Our aim was to analyse whether using delayed enhancement cardiac magnetic resonance imaging (DE-CMR) to localize veno-atrial gaps in atrial fibrillation (AF) redo ablation procedures improves outcomes during follow-up. We conducted a case-control study with 35 consecutive patients undergoing a DE-CMR-guided Repeat-pulmonary vein isolation (Re-PVI) procedure. Those with more extensive ablations (e.g. roof lines, box) were excluded. Patients were matched for age, sex, AF pattern, and left atrial dimension with 35 patients who had undergone a conventional Re-PVI procedure guided with a three dimensional (3D)-navigation system. Procedural characteristics were recorded, and patients were followed for 24 months in a specialized outpatient clinic. The primary endpoint was freedom from recurrent AF, atrial tachycardia, or flutter. The duration of CMR-guided procedures was shorter compared to the conventional group (161 ± 52 vs. 195 ± 72 min, respectively, P = 0.049), with no significant differences in fluoroscopy or total radiofrequency time. At the 2-year follow-up, more patients in the DE-CMR-guided group remained free from recurrences compared with the conventional group (70% vs. 39%, respectively, P = 0.007). In univariate Cox-regression analyses, AF pattern [persistent AF, hazard ratio (HR) 2.66 (1.27-5.46), P = 0.006] and the use of DE-CMR [HR 0.36 (0.17-0.79), P = 0.009] predicted recurrences during follow-up; both factors remained independent predictors in multivariate analyses. The substrate characterization provided by DE-CMR facilitates the identification of anatomical veno-atrial gaps and associates with shorter procedures and better clinical outcomes in repeated AF ablation procedures.

Impact of multimorbidity and polypharmacy on the management of patients with atrial fibrillation: insights from the BALKAN-AF survey

Objective We investigated the impact of multimorbidity and polypharmacy on the management of atrial fibrillation (AF) patients in clinical practice and assessed factors associated with polypharmacy and oral anticoagulation (OAC) use in AF patients with multimorbidity and polypharmacy. Methods A 14-week prospective study of consecutive non-valvular AF patients was performed in seven Balkan countries. Results Of 2712 consecutive patients, 2263 patients (83.4%) had multimorbidity (AF + ≥2 concomitant diseases) and 1505 patients (55.5%) had polypharmacy. 1416 (52.2%) patients had both multimorbidity and polypharmacy. Overall, 1164 (82.2%) patients received OAC, 200 (14.1%) patients received antiplatelet drugs alone and 52 (3.7%) patients had no antithrombotic therapy (AT). Non-emergency centre and paroxysmal AF were significantly associated with OAC non-use in patients with multimorbidity, whilst age ≥80 years and non-emergency centre were identified to be independent predictors of OAC non-use in patients with polypharmacy. Conclusions Multimorbidity and polypharmacy were common among AF patients in our study. AT was suboptimal and approximately 18% of multimorbid patients with polypharmacy were not anticoagulated. Pattern of AF and non-emergency centre were associated with OAC non-use in AF patients with multimorbidity, whilst non-emergency centre and age ≥80 years were associated with OAC non-use in AF patients with polypharmacy. Key Message Multimorbidity and polypharmacy are common among patients with AF. Antithrombotic therapy was suboptimal in AF patients with multimorbidity and polypharmacy. Approximately, 18% of multimorbid patients with polypharmacy were not anticoagulated.

Recurrence of Atrial Fibrillation After Catheter Ablation or Antiarrhythmic Drug Therapy in the CABANA Trial

BackgroundThe CABANA (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation) trial randomized 2,204 patients with atrial fibrillation (AF) to catheter ablation or drug therapy. Analysis by intention-to-treat showed a nonsignificant 14% relative reduction in the primary outcome of death, disabling stroke, serious bleeding, or cardiac arrest. ObjectivesThe purpose of this study was to assess recurrence of AF in the CABANA trial. MethodsThe authors prospectively studied CABANA patients using a proprietary electrocardiogram recording monitor for symptom-activated and 24-h AF auto detection. The AF recurrence endpoint was any post–90-day blanking atrial tachyarrhythmias lasting 30 s or longer. Biannual 96-h Holter monitoring was used to assess AF burden. Patients who used the CABANA monitors and provided 90-day post-blanking recordings qualified for this analysis (n = 1,240; 56% of CABANA population). Treatment comparisons were performed using a modified intention-to-treat approach. ResultsMedian age of the 1,240 patients was 68 years, 34.4% were women, and AF was paroxysmal in 43.0%. Over 60 months of follow-up, first recurrence of any symptomatic or asymptomatic AF (hazard ratio: 0.52; 95% confidence interval: 0.45 to 0.60; p < 0.001) or first symptomatic-only AF (hazard ratio: 0.49; 95% confidence interval: 0.39 to 0.61; p < 0.001) were both significantly reduced in the catheter ablation group. Baseline Holter AF burden in both treatment groups was 48%. At 12 months, AF burden in ablation patients averaged 6.3%, and in drug-therapy patients, 14.4%. AF burden was significantly less in catheter ablation compared with drug-therapy patients across the 5-year follow-up (p < 0.001). These findings were not sensitive to the baseline pattern of AF. ConclusionsCatheter ablation was effective in reducing recurrence of any AF by 48% and symptomatic AF by 51% compared with drug therapy over 5 years of follow-up. Furthermore, AF burden was also significantly reduced in catheter ablation patients, regardless of their baseline AF type. (Catheter Ablation vs Anti-arrhythmic Drug Therapy for Atrial Fibrillation Trial [CABANA]; NCT00911508)

Clinical assessment of AF pattern is poorly correlated with AF burden and post ablation outcomes: A CIRCA-DOSE sub-study

BackgroundContemporary guidelines recommend that atrial fibrillation (AF) be classified into paroxysmal and persistent AF based on clinical assessment, with these categorizations forming the basis of therapeutic recommendations. While pragmatic, clinical assessment may introduce misclassification errors, which may impact treatment decisions. We sought to determine the relationship between AF classification, baseline AF burden, and post-ablation arrhythmia outcomes. DesignThe current study is a sub-analysis of a prospective, parallel-group, multicenter, single-blinded randomized clinical trial. All 346 patients enrolled in CIRCA-DOSE received an implantable cardiac monitor a median of 72 days prior to ablation. AF was classified as low burden paroxysmal, high burden paroxysmal, or persistent based on clinical assessment prior to device implantation. Prior to ablation patients were re-classified using the same definitions based on device monitoring data. Correlation between classifications, AF burden, and post-ablation arrhythmia outcomes were assessed. ResultsThere was poor agreement between clinical and device-based AF classification (Cohen's kappa: 0.192). AF classification derived from pre-ablation continuous monitoring reflected baseline and post-ablation AF burden with greater accuracy and with less overlap between the AF classes (P < 0.01 for all categorical comparisons). Patients objectively classified as “Low Burden” paroxysmal by continuous monitoring data had significantly greater freedom from recurrent AF/AT/AFL compared to those classified as “High Burden” paroxysmal (hazard ratio [HR] 0.57 for AF/AT/AFL recurrence) or persistent AF (HR 0.19 for AF/AT/AFL recurrence). ConclusionsClassification of AF pattern based on pre-ablation continuous cardiac rhythm monitoring better predicted AF burden and freedom from recurrent AF post ablation. Despite the use of standardized definitions, classification of AF based on clinical assessment did not predict baseline AF burden, post ablation AF burden, or freedom from recurrent AF post ablation.Trial registration: ClinicalTrials.govNCT01913522.

Abstract P503: Continuous Diurnal Patterns of Atrial Fibrillation Onset by Chronic Kidney Disease Status: The Atherosclerosis Risk in Communities (aric) Study

Background: Chronic kidney disease (CKD) is associated with atrial fibrillation (AF); however, most studies have looked at its presence or occurrence as a dichotomous outcome, and diurnal patterns of AF by CKD status have not yet been characterized. Methods: Of 2257 adults (71-94 years) who underwent 2 weeks of non-invasive continuous heart rhythm monitoring using the Zio XT Patch, we examined 61 participants with paroxysmal AF and characterized the probability of AF onset over the course of 24 hours using a generalized function-on-scalar regression model. CKD status was defined using eGFR and albuminuria. Results: The median device wear-time was 13.7 (12.6, 13.9) days, and the majority (57%) had CKD. In non-CKD, the probability of AF onset fluctuated over 24 hours with two nadir periods occurring in late morning (~10am) and late evening (~10pm), and somewhat prominent peaks occurring in early morning (~8am) and early evening (~6pm) [figure] . Overall, CKD had a higher probability of AF compared to non-CKD. CKD also demonstrated a less pronounced nadir in late evening, and was significantly more likely to experience AF during this time (OR 2.80; 95% CI 1.05, 11.94) compared to non-CKD. This observation was consistent even after adjusting for various potential confounders such as age, sex, race, diabetes, and a history of cardiovascular disease. Conclusion: Based on 2-week monitoring, AF onset seems to exhibit a diurnal pattern throughout the day with peaks in the early morning and evening, and nadir in late morning and evening. Compared to those without CKD, those with CKD are more likely to experience AF in late evening, suggesting a potential high-risk time window for monitoring. Further studies are needed to evaluate prognostic value of AF diurnal patterns.

Is there any Link Between Vitamin D and Recurrence of Atrial Fibrillation after Cardioversion?

IntroductionAtrial fibrillation (AF) is the most common chronic arrhythmia in the elderly population. In symptomatic patients, restoration and maintenance of sinus rhythm improve quality of life. Unfortunately, AF recurrence still occurs in a considerable number of patients after cardioversion (CV). In this study, we aimed to evaluate the association between vitamin D (VitD) and AF recurrence after electrical or medical CV.MethodA total of 51 patients who underwent CV for symptomatic AF were included in the study. AF recurrence was defined as an AF pattern in 12-lead electrocardiography (ECG) recording after CV within 6 months or ECG Holter recording of AF lasting more than 30 seconds at 6-month follow-up.ResultsMean vitD level was 21.4 ng/ml in our study population. VitD level was lower in the AF recurrence group than in the non-recurrence group (18 ng/ml vs. 26.3 ng/ml, respectively; P=0.001). Additionally, left atrial diameter was larger in the AF recurrence group compared to the non-recurrence group (4.4 vs. 4.1, P=0.025). Patients with AF recurrence were older than patients without AF recurrence, and, although the prevalence of hypertension is higher in the AF recurrence group, there was no statistically significant difference (P=0.107, P=0.867).ConclusionIn our study, there is a strong association between vitD level and AF recurrence after CV. VitD deficiency might be a predictor of high risk of AF recurrence after CV and vitD supplementation during the follow-up might help the maintenance of sinus rhythm.

P204 Automated detection of atrial fibrillation based on stationary wavelet transform and artificial neural network targeted for embedded system-on-chip technology

Abstract Stroke is one of the most severe cardiovascular disease which can potentially cause permanent disability. Atrial Fibrillation (AF) is one of the major risk factors of stroke that can be detected from electrocardiogram (ECG) monitoring. Objective This study proposed an AF detection algorithm based on stationary wavelet transform (SWT) and artificial neural network (ANN) for screening purpose. The algorithm is aimed for embedded System-on-Chip (SoC) technology deployment as a standalone AF classifier for community in rural area where the internet infrastructure may not well established. Methods After standard ECG signal pre-processing, SWT is applied to filtered ECG and produces 12 sets of primary features in time-frequency domain. The power spectral density (PSD) and log energy entropy (LogEn) were calculated from these 12 sets of primary features, to measure atrial activity fall in frequency range of 4 to 9 Hz, and the randomness of an ECG signal caused by AF, respectively. Finally, the ANN classifier recognizes the pattern of AF based on high atrial activity and randomness of ECG signal. Algorithm exploration is carried out to determine the optimum parameter value which can yield the best classification and suitable to be implemented in embedded SoC technology for real-time computation performance. ECG training and testing datasets of the proposed AF detection algorithm were extracted from MIT-BIH Atrial Fibrillation Database which consists of 23 ECG record with each record contains a 10 hours ECG data. Results AF detection accuracy is 95.3% which was able to classify an ECG signal into categories of AF, sinus rhythm, and other arrhythmia. Conclusion The proposed AF detection algorithm based on combination of SWT and ANN can achieve high accuracy and is suitable to be implemented as a standalone AF classifier based on embedded SoC technology targeted for early detection of AF in the community.

The association between patterns of atrial fibrillation, anticoagulation, and cardiovascular events.

AimsGuidelines do not recommend to take pattern of atrial fibrillation (AF) into account for the indication of anticoagulation (AC). We assessed AF pattern and the risk of cardiovascular events during 2-years of follow-up. Methods and resultsWe categorized AF as paroxysmal, persistent, or permanent in 29 181 patients enrolled (2010–15) in the Global Anticoagulant Registry In the FIELD of AF (GARFIELD-AF). We used multivariable Cox regression to assess the risks of stroke/systemic embolism (SE) and death across patterns of AF, and whether this changed with AC on outcomes. Atrial fibrillation pattern was paroxysmal in 14 344 (49.2%), persistent in 8064 (27.6%), and permanent 6773 (23.2%) patients. Median CHA2DS2-VASc, GARFIELD-AF, and HAS-BLED scores assessing the risk of stroke/SE and/or bleeding were similar across AF patterns, but the risk of death, as assessed by the GARFIELD-AF risk calculator, was higher in non-paroxysmal than in paroxysmal AF patterns. During 2-year follow-up, after adjustment, non-paroxysmal AF patterns were associated with significantly higher rates of all-cause death, stroke/SE, and new/worsening congestive heart failure (CHF) than paroxysmal AF in non-anticoagulated patients only. In anticoagulated patients, a significantly higher risk of death but not of stroke/SE and new/worsening CHF persisted in non-paroxysmal compared with paroxysmal AF patterns. ConclusionIn non-anticoagulated patients, non-paroxysmal AF patterns were associated with higher risks of stroke/SE, new/worsening HF and death than paroxysmal AF. In anticoagulated patients, the risk of stroke/SE and new/worsening HF was similar across all AF patterns. Thus AF pattern is no longer prognostic for stroke/SE when patients are treated with anticoagulants. Clinical Trial RegistrationURL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362.

P1913Implantable Loop Recorder Detected Pattern of Atrial Fibrillation Recurrence Following Cryoballoon Pulmonary Vein Isolation in Patients with Persistent Atrial Fibrillation

Abstract Background Cryoballoon (CB) pulmonary vein isolation (PVI) is increasingly being used in patients (pts) with persistent atrial fibrillation (AF). However, there are limited data about the pattern of atrial fibrillation (AF) recurrence in these pts. Objective To assess, using an implantable loop recorder (ILR), the patterns of AF recurrence following CB PVI in pts with persistent atrial fibrillation. Methods We enrolled consecutive pts with persistent AF ablation undergoing their first CB ablation. Other cavotricuspid isthmus ablation when indicated, no other ablation was performed. A Reveal LINQ ILR (Medtronic) was implanted &lt;3 months following ablation; all pts had a minimum of 1-year follow-up. The recurrence of any atrial arrhythmia was determined and adjudicated; 4 distinct AF patterns were characterized (Figure). Results We studied 64 pts (66±9 years; 50 [78%] male; CHA2DS2-VASc 2.6±1.9) with persistent AF; 52 (81%) pts were on an antiarrhythmic drug (AAD) peri-ablation. During 803±361 days of follow-up, 33 (52%) pts had their 1st AF recurrence 91–365 days post-ablation and another 17 (27%) pts had their 1st AF recurrence &gt;365 days post-ablation. No AF was seen in 14 (31%) pts. Most pts (33 of 50, 66%) with AF recurrence presented with 1 of 3 distinct patterns of paroxysmal AF (Figure), which ranged from 22 min to 124 hours. In 2/3 of these pts, all AF recurrences lasted &lt;24 hours. Only 17 (34%) pts recurred with persistent AF. Conclusion Following single CB PVI, most pts with persistent AF remained free of persistent AF during long-term follow-up. Most pts with recurrent AF have 1 of 3 distinct patterns with episodes commonly last &lt;24 hours. These data suggest that CB PVI ablation may halt AF progression in pts initially presenting with persistent AF.

COMPARISON OF CLINICAL AND DEVICE-BASED CLASSIFICATION OF PAROXYSMAL/PERSISTENT ATRIAL FIBRILLATION AND OUTCOMES WITH ABLATION: INSIGHTS FROM CONTINUOUS IMPLANTABLE DEVICE MONITORING

Contemporary guidelines recommend that the clinical pattern of atrial fibrillation (AF) be assessed and classified based on episode duration, with AF defined as paroxysmal if the episode duration is < 7 days and persistent if >7 days. These clinically determined AF patterns have been used to characterize disease severity, define populations in trials, and form the basis of therapeutic recommendations.

Clinical benefits and risks of antithrombotic therapy in patients with atrial fibrillation with comorbidities – A report from the CHART-2 Study

BackgroundThe benefits of antithrombotic therapy (ATT) for atrial fibrillation (AF) are occasionally offset by major bleeding complications. However, the clinical benefits and risks of ATT in AF patients, with special references to comorbidities, such as heart failure (HF), coronary artery disease (CAD), and the patterns of AF, remain to be fully elucidated. MethodsA total of 3221 consecutive AF patients from our Chronic Heart Failure Analysis and Registry in the Tohoku District-2 (CHART-2) Study (N = 10,219) were divided into 4 groups based on ATT at enrollment; no-ATT, anticoagulant alone, antiplatelet alone, and both of them (AC&AP). Then, efficacy and safety outcomes including thromboembolic events, major bleeding, and mortality were evaluated among the 4 groups. ResultsAnticoagulant monotherapy was associated with reduced risk of ischemic stroke in patients with but not in those without HF, CAD, or non-paroxysmal AF. Although there was no significant difference in major bleeding among the 4 groups, a composite of thromboembolism and major bleeding occurred more frequently in the AC&AP group, even in combination with anticoagulants and single antiplatelet therapy, indicating that the combination therapy is more harmful than anticoagulant monotherapy for AF patients, especially for those with HF or CAD. Lastly, no-ATT group was associated with worse prognosis compared with other 3 groups. ConclusionsThese results indicate that ATT is beneficial for AF patients particularly for those with HF, CAD, or non-paroxysmal AF and that among ATT, anticoagulant monotherapy may be most profitable for both clinical benefits and risks for AF patients.

Nonlinear dynamic approaches to identify atrial fibrillation progression based on topological methods

In recent years, atrial fibrillation (AF) development from paroxysmal to persistent or permanent forms has become an important issue in cardiovascular disorders. Information about AF pattern of presentation (paroxysmal, persistent, or permanent) was useful in the management of algorithms in each category. This management is aimed at reducing symptoms and stopping severe problems associated with AF. AF classification has been based on time duration and episodes until now. In particular, complexity changes in Heart Rate Variation (HRV) may contain clinically relevant signals of imminent systemic dysregulation. A number of nonlinear methods based on phase space and topological properties can give more insight into HRV abnormalities such as fibrillation. Aiming to provide a nonlinear tool to qualitatively classify AF stages, we proposed two geometrical indices (fractal dimension and persistent homology) based on HRV phase space, which can successfully replicate the changes in AF progression. The study population includes 38 lone AF patients and 20 normal subjects, which are collected from the Physio-Bank database. “Time of Life (TOL)” is proposed as a new feature based on the initial and final Čech radius in the persistent homology diagram. A neural network was implemented to prove the effectiveness of both TOL and fractal dimension as classification features. The accuracy of classification performance was 93%. The proposed indices provide a signal representation framework useful to understand the dynamic changes in AF cardiac patterns and to classify normal and pathological rhythms.