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External defibrillation is a common treatment for the cardiac arrhythmia atrial fibrillation. Electrode placement has been shown to affect defibrillation efficacy and required energy levels. We suggest investigating the relationship between esophageal electric fields (EEFs) and atrial defibrillation thresholds to determine the feasibility of creating patient-specific electrode placements using EEFs. This study presents the design and implementation of an esophageal probe (EP) that accurately measures three-dimensional electric fields. The root-mean-square error of the EP was 1.69% as determined by measurements performed in an electrolytic tank. The EP also performed well during in vivo testing in a pig. There was a strong positive relationship between EEF2s and applied energy during defibrillation strength shocks. The EEF measurements were also repeatable, with less than 4.24% difference between repeated shocks. This is the first description of a probe designed specifically for measuring electric fields in the esophagus. [ABSTRACT FROM AUTHOR]

Introduction: This prospective observational study aimed to investigate the incidence of symptomatic and silent cerebral thromboembolisms after balloon-based ablation of paroxysmal atrial fibrillation (PAF) in patients receiving periprocedural oral anticoagulation with direct oral anticoagulants (DOACs), and compare that between cryoballoon ablation (CBA) and HotBalloon ablation (HBA). Methods: We enrolled 106 consecutive patients (65 ± 10 years; 86 males) undergoing balloon-based pulmonary vein isolation (PVI) of PAF and brain magnetic resonance (MR) imaging on the next day after the ablation procedure (CBA, n = 54; HBA, n = 52). The DOACs were uninterrupted in 47 patients (CBA, n = 21; HBA, n = 26) throughout the periprocedural period, and interrupted in 59 patients (CBA, n = 33; HBA, n = 26) on the day of the procedure. Intravenous heparin was infused to maintain an activated clotting time (ACT) of 300 - 400 seconds during the procedure. Results: No symptomatic thromboembolisms occurred in this series. Silent cerebral ischemic lesions (SCILs) were detected on MR imaging in 20 patients (18.9%), and the incidence of SCILs did not significantly differ between the CBA and HBA groups (24.1% vs. 13.5%; P = 0.163). The CBA group included fewer patients requiring touch-up ablation than the HBA group (18.9% vs. 36.5%; P = 0.043), while the age, CHA2DS2-VASc score, left atrial size, total procedure time, intraprocedural ACT value, and percentage of periprocedural DOAC continuation did not significantly differ between the two groups. According to the multivariable logistic regression analysis, an older age was an independent positive predictor of SCILs after the balloon-based PVI (odds ratio 1.089; 95% confidence interval, 1.014 - 1.169; P = 0.019), but neither the balloon catheter type (CB or HB) nor periprocedural continuation or discontinuation of the DOACs were significant predictors. The incidence of major and minor bleeding complications was comparable between the CBA and HBA groups (1.9% vs. 0%, P = 0.509; 9.3% vs. 5.8%, P = 0.379). Conclusions: Both the CBA and HBA of PAF revealed a similar incidence of post-ablation cerebral thromboembolisms. Elderly patients may be at a risk of SCILs after a balloon-based PVI with periprocedural DOAC treatment. [ABSTRACT FROM AUTHOR]

Introduction: There is substantial evidence of impaired health related quality of life (HRQoL) in patients with paroxysmal atrial fibrillation (PAF). Few studies have evaluated self-management programs aiming to decrease symptoms and improve HRQoL, in patients with PAF. Yoga has been shown to improve HRQoL, decrease blood pressure, heart rate as well as NT-ProBNP, among patients with heart failure and hypertension. Hypothesis: Yoga improves HRQoL, decrease blood pressure, heart rate as well as NT-ProBNP in patients with PAF. Methods: In this randomized controlled study, with stratification of gender, 132 patients with symptomatic PAF were randomized to yoga-(n=44), relaxation- (n=44) or control group (n=44). The yoga group performed MediYoga once a week during 12 weeks. The relaxation group listened to relaxing music, specifically used in other stress relief programs, once a week for 12 weeks. The control group only received standard treatment. HRQoL, blood pressure, heart rate as well as NT-ProBNP were assessed at baseline and at the end of the study (12 (+2) weeks). ASTA (disease specific form) and SF-36 (general form) were used to measure HRQoL. Results: At the end of the study there was a significant improvement of HRQoL parameters SF-36 in bodily pain, general health, social function, mental health and in dimension MCS within the yoga group (p = 0.014, p = 0.037, p = 0.029, p = 0.030, p = 0.019). There were no differences between other parameters in SF-36 or among the ASTA parameters. There were no differences in heart rate and NTPro-BNP between the groups. Systolic blood pressure decreased significantly in the yoga group (134±18 to 127±13) compared to the control group (126±17 to 127±15), p = 0.041, but no difference was seen compared to the relaxation group (131±17 to 125±12). Moreover, diastolic blood pressure decreased significantly in the yoga group (79±9 to 74 ±9) compared to the control group (76±9 to 79±8), p = 0.005, but no difference was seen compared to the relaxation group (76±9 to 77±8). Conclusions: MediYoga affects HRQoL positively and decrease blood pressure in patients with PAF. MediYoga may be used as a self-management program among patients with PAF. [ABSTRACT FROM AUTHOR]

Introduction: The evolution of defibrillation waveforms has dramatically progressed over time. Monophasic waveform became the standard waveform used in most defibrillators until the 1980s, and were progressively replaced after year 2000 by newer biphasic waveforms with different patterns: initially the biphasic rectilinear waveform, then biphasic truncated exponential (BTE) waveform (with high or low energy), and pulsed energy BTE. Hypothesis: Our aim was to collect data regarding the efficacy of low, high and pulsed energy of biphasic truncated exponential waveforms, in cardioversion for atrial fibrillation through a systematic research on the literature. Methods: A systematic research on PubMed and Science Direct, with key words (cardioversion atrial fibrillation biphasic waveform) and filters (title/abstract, clinical trial, English) provided 38 articles. A further selection was made by their title and abstract leading to a final selection of 6 articles. Efficacy was defined as return to sinus rhythm. Results: The figure provides cumulative energy dose-response curves for different BTE waveforms: 4 High Energy (HE) 360J, 3 Low Energy (LE) 200J and 3 Pulsed Energy 200J. Legend of the figure indicates for each study the year of publication, the recruitment period, the sample size, the delay between cardioversion and observed rhythm, and the percentage of patients in atrial flutter when appropriate. Although the studies present major disparities, the dose-response curves concentrate within 85% and 95% efficacy and 300 and 500 Joules cumulative energy. Three curves are significantly deviating from the seven others. The low efficiency due to a defective device and the high efficiencies associated to a short outcome's reading at 5s instead of 1min. Conclusion: Dose-response curves of high, low or pulsed energy of biphasic truncated exponential are rather similar, with efficacy ranging between 85% and 95% for cumulative energy between 300 and 500 Joules. [ABSTRACT FROM AUTHOR]

Introduction: Electrical cardioversion (CV) for atrial fibrillation (AF) has been occasionally reported to cause thromboembolic events due to the transient left atrial appendage (LAA) dysfunction, which is called as LAA-stunning. However, predictive factor for the occurrence of LAA-stunning after CV has not been well studied. We investigated the risk factors of LAA-stunning after CV in patients with AF. Hypothesis: Clinical factors can predict for LAA-stunning. Methods: One hundred thirty-four patients who underwent catheter ablation (CA) for non-paroxysmal AF were studied (103 males, 68±9 years). Internal-CV was performed in all patients, and LAA emptying fraction (LAA-EF) was assessed using LAA angiography before and just after internal-CV. LAA-stunning was defined as 10% reduction of LAA-EF after CV. Patients with LAA akinesis (defined as LAA-EF <10%) in LAA angiography before CV excluded. Results: LAA-stunning was observed in 45/134 patients (34%). Patients with LAA-stunning had larger left atrial (LA) volume (p=0.001), longer AF duration (p=0.003), elevated brain natriuretic peptide (BNP) (p=0.001), not taking calcium blocker (p=0.022), and higher E wave (p=0.007). On multivariate analysis, elevated BNP (p=0.038, OR 1.041 for each 1 pg/mL increase in BNP, 95%CI 1.001-1.009) and long AF duration (p=0.015, OR 1.033 for each 1-month prolong in AF lasting duration, 95%CI 1.006-1.073) were associated with LAA-stunning. In addition, all patients were divided into four groups based on the combination between BNP and AF lasting duration. Prevalence rate of LAA-stunning in patients with high BNP (> 58.2 pg/mL) and long-lasting AF (>14 days) was 55.6%. (Figure) Conclusion: The more powerful anticoagulation therapy might be needed post electrical cardioversion in patients with elevated BNP and long AF duration. [ABSTRACT FROM AUTHOR]

Background: Prior proteomics analyses on the risk of incident AF screened for limited numbers of proteins. We report the use of single-stranded DNA-based aptamers as affinity agents to screen for 1373 proteins and identify novel biomarkers that are associated with risk of incident AF in a prospective cohort study. Methods: We studied the Framingham Heart Study Offspring Cohort participants who attended exam 5 from 1991 to 1995. We ascertained AF or atrial flutter on ECG at routine research visits and from clinical records review. Participants with prevalent AF (n=28) were excluded. Plasma protein levels were measured by the SOMAscan proteomic profiling platform, which uses single-stranded DNA-based aptamers to capture conformational protein epitopes. We used robust inference for the Cox proportional hazards models to relate each protein level with incident AF. In addition, we examined the association between AF-related genetic loci and circulating protein levels. Results: Our study included 1,885 participants (mean age 55±10 years, 54% women) who had proteomic profiles measured. A total of 349 participants developed AF during follow-up (mean follow-up 18.3 years). We found 8 proteins that were significantly associated with incident AF after adjusting for age, sex, and technical covariates and correction for multiple testing (p <0.05/1373=3.64x10-5). After additional adjustments for clinical factors (smoking, height, weight, systolic and diastolic blood pressures, antihypertensive treatment, diabetes mellitus, prevalent myocardial infarction, prevalent heart failure) associated with AF, ADAMTS13 and NT-proBNP (HR, 0.78; 95% CI, 0.70-0.88; and 1.44; 95% CI, 1.22-1.70, respectively; p <3.64x10-5 for both) remained significantly associated with the risk of incident AF. None of the 8 proteins were associated AF-related genetic loci previously identified in recent genome-wide association studies. Conclusions: In our proteomic analysis of longitudinal community-based sample, we identified 8 proteins associated with risk of incident AF after adjustment for age and sex. Future studies are needed to identify whether they are mechanistically related to AF development and whether they are clinically useful for identification of future AF risk. [ABSTRACT FROM AUTHOR]