bluuebunny/crossref_metadata_2025_split huggingface dataset:
A nationwide 16-year study of the trends, burden and impact of atrial fibrillation in cardiac amyloidosis
Authors: Isath A , Perembeti S , Ho K , Correa A , Haider S.W , Siroky G , Narasimhan B , Padmanabhan D , Mehta D 
Published: November 2020

Abstract

Background
Cardiac amyloidosis (CA) remains an underdiagnosed entity. Atrial fibrillation (AF) is common in patients with CA, likely owing to direct amyloid deposition in the left atrium. However, the prevalence of AF in CA and its association with in-hospital outcomes has not been studied in large populations.

Purpose
Our aim was to study the trends, baseline characteristics, and clinical impact of AF in patients with CA in the United States using the Healthcare Cost and Utilization Project (HCUP) National) Inpatient Sample (NIS) from 1999 to 2014.

Methods
We queried the NIS and identified CA using ICD-9-CM codes 277.39 and 425.7. AF in CA patients was identified using the ICD-9-CM code of 427.31. Statistical Analysis System (SAS) 9.4 was used for analysis of data.

Results
There were a total of 145,920 CA hospitalizations between 1999 and 2014 in the United States, of which 37,070 (25.4%) had AF. The prevalence of AF remained consistent from 27.5% in 1999 to 27.4% in 2014.
The mean age of patients with AF was 72.9±28.2 years and for patients without AF was 67±31.9 years (p&lt;0.0001). The majority of the patients with AF were male (60.3%) and the study group was predominantly white (62.8% in patients with AF and 56.4% in patients without AF). CA patients with AF suffered more from thyroid-related disease (22.5% vs 16.1%), heart failure (62.9% vs 36.5%) and renal failure (34.7% vs 30.5%) and less from hypertension (29.3% vs 34.0%) and diabetes mellitus (23.2% vs 25.2%) (p&lt;0.0001). There was no significant difference in the Charlson comorbidity score between the groups.
Inpatient mortality was significantly higher in CA patients with AF (10.4% vs 6.5%, p&lt;0.001). However, in-patient mortality has been decreasing over the years from 10.3% in 1999 to 7.6% in 2014. Furthermore, cardiogenic shock was significantly higher in CA patients with AF (2.1% vs 1.2%, p&lt;0.001), yet the use of mechanical circulatory support was not significantly different between the groups (0.42% vs 0.35%, p=0.375). Pacemaker implantation was also noted to be higher in CA patients with AF compared to patients without AF (2.8% vs 1.2%, p&lt;0.0001).
There was no significant difference between CA patients with and without AF in mean cost of hospitalization ($58222±10752 vs $57695±545, p=0.081) or length of stay (7.9±0.1 vs 7.7±0.1 days, p=0.7089).

Conclusion
CA with atrial fibrillation is a well-recognized entity, and our large scale retrospective analysis found significant association with worse in-hospital outcomes and cardiogenic shock. Interestingly, trend of in-patient mortality in CA has been decreasing over the years, likely owing to improved imaging modalities for diagnosis. Optimal management of AF in CA is imperative to improve outcomes in this population.

Funding Acknowledgement
Type of funding source: None
A prognostic nomogram for event-free survival in patients with atrial fibrillation before cardiac resynchronization therapy
Authors: Cai M , Hua W , Yang S.W , Zhang N.X , Hu Y.R , Gu M , Niu H.X , Zhang S 
Published: November 2020

Abstract

Background
Atrial fibrillation (AF), one of the most common comorbidities with heart failure (HF), is associated with worse prognosis in HF patients receiving cardiac resynchronization therapy (CRT). However, there is still no convenient tool to evaluate and identify patients with high risk of mortality and hospitalization due to heart failure in CRT candidates with AF.

Methods
We included 152 consecutive patients with AF for CRT in our hospital from January 2009 to July 2019. Multivariate Cox regression was applied to derive a nomogram, using multiple imputation for missing values and backward stepwise regression for variable selection.

Results
Five predictors were incorporated in the nomogram, including N-terminal pro brain natriuretic protein (NTproBNP) &gt;1745pg/mL, history of syncope, previous pulmonary hypertension (PHP), moderate or severe tricuspid regurgitation (TR), thyroid stimulating hormone (TSH) &gt;4mIU/L. Concordance index (0.70, 95% CI 0.62–0.77), corrected concordance index (0.67, 95% CI 0.59–0.74) and calibration curve showed optimal discrimination and calibration of the established nomogram. Significant difference of overall event-free survival was recognized by the nomogram-derived scores in patients with high risk (&gt;50 points), intermediate risk (21–50 points) and low risk (0–20 points) before CRT.

Conclusion
Our nomogram may be an applicable tool for early risk stratification among CRT candidates with AF.
Nomogram and risk stratification

Funding Acknowledgement
Type of funding source: None
Relationship between left atrial strain and left atrial bipolar voltage in patients undergoing catheter ablation for atrial fibrillation
Authors: Takahashi Y , Kitai T , Watanabe T , Fujita T 
Published: November 2020

Abstract

Background
Low-voltage zone (LVZ) in the left atrium (LA) seems to represent fibrosis. LA longitudinal strain assessed by speckle tracking method is known to correlate with the extent of fibrosis in patients with mitral valve disease.

Purpose
We sought to identify the relationship between LA longitudinal strain and LA bipolar voltage in patients with atrial fibrillation (AF). We tested the hypothesis that LA strain can predict LA bipolar voltage.

Methods
A total of 96 consecutive patients undergoing initial AF ablation were analyzed. All patients underwent transthoracic echocardiography including 2D speckle tracking measurement on the day before ablation during sinus rhythm (SR group, N=54) or during AF (AF group, N=42). LA longitudinal strain was measured at basal, mid, and roof level of septal, lateral, anterior, and inferior wall in apical 4- and 2-chamber view. Global longitudinal strain (GLS) was defined as an average value of the 12 segments. LA voltage map was created using EnSite system, and global mean voltage was defined as a mean of bipolar voltage of the whole LA excluding pulmonary veins and left atrial appendage. LVZ was defined as less than 1.0 mV.

Results
There was a significantly positive correlation between GLS and global mean voltage (r=0.708, p&lt;0.001). Multivariate regression analysis showed that GLS and age were independent predictors of global mean voltage. There was a significant negative correlation between global mean voltage and LVZ areas.

Conclusions
There was a strong correlation between LA longitudinal strain and LA mean voltage. GLS can independently predict LA mean voltage, subsequently LVZ areas in patients with AF.

Funding Acknowledgement
Type of funding source: None
Radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique: 4-year follow-up
Authors: Kettering C 
Published: November 2020

Abstract

Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. Cryoablation has been shown to be a safe and effective technique for pulmonary vein isolation. However, there is a significant arrhythmia recurrence rate after cryoablation procedures and there are no established strategies for redo procedures in these patients. Therefore, we have summarized our experience with radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique (including an analysis of pulmonary vein conduction recovery patterns ater procedures performed with the first or second generation cryoballoon).

Methods
One hundred and fifty patients (paroxysmal AF: 99 patients, persistent AF: 51 patients) had to undergo a redo procedure after initially successful circumferential PV isolation with the cryoballoon technique (Arctic Front Balloon: 75 patients (group A); Arctic Front Advance: 75 patients (group B)). The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy (CARTO) depending on the intra-procedural findings.

Results
During the redo procedure, a mean number of 1.7 re-conducting PVs were detected (using a circular mapping catheter; group A: 2.1 re-conducting PVs, group B: 1.3 re-conducting PVs). There was a slightly higher incidence of chronic PV reconnections related to the left-sided PV ostia than to the right-sided PVs in both groups. Furthermore, sites of chronic PV reconnection were found more frequently in the inferior parts of the PV ostia than in the superior parts. In 65 patients in group A, a segmental approach was sufficient to eliminate the residual PV conduction because there were only a few recovered PV fibers (1–3 reconnected PVs; group A1). In the remaining 10 patients in group A, a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction of all four pulmonary veins (group A2). In group B, a segmental approach was sufficient in all patients because there was only a minor reconnection of 1–2 PVs. All recovered PVs could be isolated sucessfully again. At 48-month follow-up, 74.7% of all patients were free from an arrhythmia recurrence (112/150 patients; group A: 51/75 patients (68%), group B: 61/75 patients (81.3%)). There were no major complications in both groups.

Conclusions
In patients with an initial circumferential PVI using the cryoballoon technique, a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation. In most cases only a few re-conducting PV fibers were found and therefore, a segmental re-ablation approach seems to be sufficient in the majority of patients (especially in patients treated with the second generation cryoballoon).

Funding Acknowledgement
Type of funding source: None
First pass isolation predicts clinical success after contact force guided paroxysmal atrial fibrillation ablation
Authors: Osorio J , Hunter T.D , Rajendra A , Zei P , Morales G 
Published: November 2020

Abstract

Background
Contact force (CF) ablation of AF with a focus on catheter-tissue contact stability optimizes clinical success and may help the operator to achieve pulmonary vein (PV) isolation in a single encirclement. While it seems evident that first pass isolation reduces procedure time, the effect on long term clinical success has not been reported.

Purpose
To evaluate the relationship between first pass isolation and freedom from atrial tachyarrhythmia recurrence at 1 year after PAF ablation.

Methods
Consecutive de novo PAF ablations were performed with a porous tip contact force catheter in 2017. All ablations used wide-area circumferential ablation and first pass isolation was captured separately for the left and right PVs. CF was held between 10–20 g and the catheter was moved every 10–20 s. RF energy was set at 40W throughout the atrium. Clinical success was defined as freedom from recurrent atrial tachyarrhythmia through 1 year following a 90-day blanking period and freedom from reablation at any time through 1 year.

Results
The population included 157 patients, age 62.7±11.5, 54.8% male, with mean CHA2DS2-VASc score of 2.3±1.5. Mean procedure times were 76.2±29.8 minutes and 89.2% of the ablations were performed with no fluoroscopy. The overall clinical success rate at 1 year was 86.1%. The number of ipsilateral PV pairs that could be isolated in a single pass was significantly associated with 1-year success (p=0.0043). Achieving first pass isolation on even one ipsilateral PV pair vs. neither pair was significantly associated with clinical success (Table).

Conclusion
In a real-world setting, first pass isolation on at least one PV side was predictive of 1 year clinical success in a PAF population ablated with CF.

Funding Acknowledgement
Type of funding source: Public Institution(s). Main funding source(s): Biosense Webster, Inc.
Low mortality rate after atrial fibrillation ablation: results from the Netherlands Heart Registration
Authors: Mol D , Roefs M.M , Blaauw Y , De Jong J.S.S.G , De Groot J.R 
Published: November 2020

Abstract

Background
Ablation therapy is widely used as a treatment of atrial fibrillation (AF) and is associated with 3.6% minor and major complications in the Netherlands. Mortality following AF ablation is rare, but has been reported 0.46% in the United States in recent literature. We hypothesize that in the Netherlands, where AF ablation is performed in high volume centres only, 30-day mortality rate is low.

Purpose
To describe 30-day mortality in the Netherlands after AF ablation.

Methods
In the Netherlands Heart Registration, all 16 Dutch ablation centres participate and 14 out of 16 centres reported AF ablation outcomes using predefined variables for quality purposes. The number of reported procedures per centre was on average 236/year [range, 33–593], where 87.5% of the centres perform &gt;150 AF ablations per year. All patients who underwent AF ablation were eligible for this analysis irrespective of ablation method used, or whether it was the first or a redo AF ablation. 30-day mortality was derived from, the municipal death registration, and individually checked by each participating ablation centre. No further analysis was available on the cause of death.

Results
In total, 20,230 patients who underwent AF ablation between 01-01-2013 and 31-12-2018 were included. The majority of patients were male (68%), mean age was 60.9±9.8 years, mean body mass index was 27.3±4.2kg/m2, and the average CHA2DS2VASc score was 1.6±1.3. Reduced left ventricular (LV) ejection fraction (&lt;50%) was present in 13.2% of the patients. Paroxysmal AF was present in 72.7% of patients, persistent AF in 24.9% and longstanding persistent in 2.3%. The index procedure was a redo-ablation in 22.7%. Mortality outcomes were available for 18,413 (91.0%) procedures, as some centres had a backlog of patients that needed death certificate checking [range, 0% - 19.4%], this factor was considered random. In total 12 patients (0.07%) died within 30-days after an AF ablation procedure. These patients were 68.5 years old [range, 55–76 years], 91.7% had a history of paroxysmal AF and 8.3% persistent AF, LV ejection fraction was &lt;50% in 8.3% and 25% of the patients had a previous AF ablation (p=0.02 for age, others p=NS).

Conclusion
Patients undergoing AF ablation in the Netherlands mainly presented with paroxysmal AF. In a setting where AF ablation is performed in high volume centres only, such as the Netherlands, 30-day mortality is very low after AF ablation.

Funding Acknowledgement
Type of funding source: None
Yoga could reduce the burden and symptoms of atrial fibrillation as well as medication related side effects and the complications with cardiac ablation
Authors: Sen N , Tanwar S , Jain A , Gokhroo R.K , Shah N 
Published: November 2020

Abstract

Background
Atrial fibrillation (AF) is a common cardiac arrhythmia that affects around three million people worldwide. Thromboembolic stroke, myocardial ischemia and congestive heart failure with significant financial burden are bad outcomes of AF. It is associated with significant morbidity and is also an independent risk factor for mortality. The treatment of AF and its associated complications increases healthcare resource utilization and contributes to increasing costs of healthcare, particularly costs associated with recurrent hospitalization.

Methods
538 patients of atrial fibrillation are enrolled in our multicentric study from 2012 to 2017 that brought to light the therapeutic impact a noninvasive, medication-free intervention has on a costly disease.The unique approach of this study involved patients serving as their own controls; for the first 12 weeks, patients continued standard AF medical or catheter ablation therapy, followed by 16 weeks of 30-min alternate day yoga sessions (Savasana / Sun Salution Yoga Posture, Ujjayi Breath and Anulom –Vilom Pranayam). Patients were also encouraged to practice yoga at home on a daily basis.We divided into two group Yoga and Non Yoga and compared the data after 16 weeks of training.

Results
Yoga training reduced symptomatic AF episodes (14.8±4 vs. 8.2±3.2, p&lt;0.005), symptomatic non-AF episodes (12.8±2.8 vs. 9.2±2.2; p&lt;0.004), asymptomatic AF episodes (2.4±0.4 vs. 1.3±0.20; p&lt;0.005), and depression and anxiety (p&lt;0.005) used Goldberg anxiety score 2.5 fold improved as compared to non yoga group while improving, QoL parameters including physical functioning, vitality, social functioning, and mental health as assessed using the SF-36 (p=0.017, p&lt;0.001, p&lt;0.001, p=0.019, and p&lt;0.003, respectively). There were significant decreases in heart rate and systolic (11±3 mmhg) and diastolic (6±2 mmhg) blood pressure after yoga training (p&lt;0.002). This may directly result in decreased hospitalization (38% in yoga vs 16% in non yoga group) and healthcare costs reduction in yoga group. Yoga is also an intervention free from medication-related side effects or the complications observed with cardiac ablation.

Conclusions
The primary outcome was a composite of the reductions in symptomatic AF, symptomatic non-AF, and asymptomatic AF episodes as recorded by a diary and correlated with a non-looping event monitor with low cost. Strikingly, the results validate the ability of yoga practice to reduce patient-reported AF symptoms. It also demonstrated a statistically significant impact on quality of life (QoL), mental health, physical functioning, depression, and anxiety with avoid of side effects of medication or ablation.

Funding Acknowledgement
Type of funding source: None
Atrial dilation as a substrate for atrial fibrillation in the canine complete chronic atrioventricular block model
Authors: Smoczynska A , Beekman H.D.M , Chui R.W , Rajamani S , Vos M.A 
Published: November 2020

Abstract

Background
Atrial fibrillation (AF) is the most common cardiac arrhythmia treated in clinical practice. Structural remodeling is characterized by atrial enlargement and contributes to the therapeutic resistance in patients with long-standing AF.

Purpose
To study the atrial arrhythmogenic and echocardiographic consequences induced by volume overload in the complete chronic atrioventricular block (CAVB) dog.

Methods
Echocardiographic and electrophysiological data was obtained in 14 anaesthetized Mongrel dogs, in acute AV-block (AAVB), after 6 weeks of CAVB (CAVB6) and CAVB10. Left atrial (LA) volume was determined with 2D echocardiography by using the biplane method. An electrocardiogram and monophasic action potentials (MAP) at the right atrial (RA) free wall were recorded. Atrial effective refractory period (AERP) was determined by continuous programmed electrical stimulation (PES) of 20 beats with a cycle length of 400 ms and an extrastimulus with decremental design until refractoriness was reached. A continuous PES protocol of 20 beats with an extrastimulus 5 ms longer than the AERP was applied for 150 seconds to trigger AF. After 5 min without arrhythmias, autonomic neuromodulation was performed by intravenous infusion (IV) of acetylcholine (1,5μg/kg/min to 6,0μg/kg/min) for 20 min followed by prompt IV infusion of isoprenaline (3μg/min) until the atrial heart rate increased by 20 bpm. PES with an extrastimulus was repeated for 150 seconds to induce AF.

Results
LA volume increased from 13.7±3.2 ml at AAVB to 20.5±5.9 ml* at CAVB6, and 22.7±6.0 ml* at CAVB10 (Fig. 1A). AERP was similar at AAVB, CAVB6, and CAVB10 (115.8±11.9, 117.3±11.7, and 106.8±12.1 ms respectively). Repetitive AF paroxysms of &gt;10 seconds were induced in 1/14 (7%) dogs at AAVB, 1/11 (9%) at CAVB6, and 5/10 (50%)* at CAVB10 (*p&lt;0.05) upon PES (Fig. 1B). Combined neuromodulation and PES did not increase the AF inducibility rate, but prolonged the longest episode of AF in the inducible dogs from 55±49 seconds to 236±202 seconds* at CAVB10 (Fig. 1C). LA volume was higher in inducible dogs 25.0±4.9 ml compared to 18.4±4.2 ml in non-inducible dogs at CAVB10.

Conclusion
Sustained atrial dilation forms a substrate for repetitive paroxysms of AF. Neuro-modulation prolongs AF episode duration in susceptible dogs. This animal model can be used to study structural remodeling of the atria and possible therapeutic advances in the management of AF.
Figure 1

Funding Acknowledgement
Type of funding source: Private company. Main funding source(s): Amgen Research
Gender-dependent regulation of FABP4 and leptin according to atrial fibrillation burden
Authors: Lopez-Canoa J.N , Couselo-Seijas M , Baluja A , Gonzalez-Melchor L , Rozados A , Llorente-Cortes V , De Gonzalo-Calvo D , Guerra J.M , Vilades D , Leta R , Martinez-Sande J.L , Garcia-Seara F.J , Gonzalez-Juanatey J.R , Eiras S , Rodriguez-Manero M 
Published: November 2020

Abstract

Aims
Adiposity plays a key role in the pathogenesis of atrial fibrillation (AF). Its associated proteins are differentially released between male and female. FABP4 and leptin are mediators in adipose tissue-inflammatory effects. Our aim was to study their gender differential behavior on mechanisms associated with AF progression.

Methods and results
Two independent cohorts were analyzed: A) patients referred for AF catheter ablation (n=217) and patients with suspected coronary artery disease referred for a CT scan (without previous history of AF) (n=105). Protein levels were determined by multiplex fluorometric immunoassay. Gene mRNA expression was analyzed by real time polymerase chain reaction. Correlation between biomarkers was explored with heatmaps and Kendall correlation coefficients. Logistic regression and random forest model determined the best predictors of AF recurrence after catheter ablation. Our results showed: 1) a distinctive profile according to gender, with an increment of FABP4 levels in women (20±14, 29±18 and 31±17 ng/mL; p=0.007) and a decrease of leptin levels in men (22±15, 13±16 and 13±11 ng/mL; p=0.001) among control, paroxysmal and persistent AF groups, respectively; 2) sex differences regarding inflammatory profile, oxidative stress and autonomic indirect markers in AF; 3) a prominent role of adipokines to discriminate AF recurrence after ablation. In persistent AF, FABP4 was the best predictor (LR coefficient 1.067, 95% CI 1–1.14, p=0.046).

Conclusion
The major finding of the present study is the sex differences of FABP4 and leptin according to AF burden. The relationship of these adipokines with oxidative stress, inflammatory and autonomic indirect markers might explain part of the mechanisms underlying the AF perpetuation.
Adipokines regarding Gender & AF burden

Funding Acknowledgement
Type of funding source: Public Institution(s). Main funding source(s): Institute of Health Carlos III