bluuebunny/crossref_metadata_2025_split huggingface dataset:
The magnitude and the course of local impedance drop to guide successful AF ablation: insight from an Italian registry
Authors: Schillaci V , Zucchelli G , Solimene F , De Simone A , Pandozi C , Stabile G , Di Cori A , Arestia A , Narducci ML , Battaglia A , Cauti F , La Greca C , Terzaghi C , Malacrida M , Segreti L 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
It has been demonstrated that an ablation strategy based on local impedance (LI) algorithm is helpful in guiding successful ablation of atrial fibrillation (AF) cases. How the magnitude and the course of LI drop could impact the effectiveness of ablation has to be proved.

Purpose
We aimed to evaluate LI drop characteristics in predicting effective radiofrequency (RF) ablation of consecutive AF cases.

Methods
Consecutive patients undergoing AF ablation at 8 Italian centers were included in the CHARISMA registry. A RF ablation catheter equipped with mini-electrodes technology and a dedicated algorithm was used to measure LI and to guide ablation. For our purpose, we defined the time to drop (τ) as the time for the first deflection of LI drop to the plateau. RF applications were targeted to a LI drop of 10 Ω and were stopped when a maximum cut-off LI drop of &lt;40 Ω was observed. Successful single RF ablation was defined according with a reduction of signal voltage by at least 50% and inability to capture local tissue on pacing. The ablation endpoint was PVI as assessed by entrance and exit block. Follow-up were scheduled at 3, 6 and 12 months post-ablation.

Results
153 consecutive patients (61% paroxysmal AF, 39% persistent AF) were enrolled in the study. 3556 point-by-point first-pass RF applications of &gt;10 s duration were performed around PVs. The mean LI drop was 13 ± 8Ω, the mean τ was 18.7 ± 13s and the median LI drop/τ was 0.67 [QI-QIII, 0.37 – 1.17] Ω/s. Both absolute drops in LI and LI drop/τ were greater at successful ablation sites (n = 3122, 88%) than at ineffective ablation sites (n = 434, 12%) (14 ± 8Ω vs 6 ± 4Ω, p &lt; 0.0001 for LI; 0.73[0.41–1.25]Ω/s vs 0.35[0.22–0.59]Ω/s for LI drop/τ, p &lt; 0.0001). Every 5-point increment in LI drop was associated with successful ablation, with an OR of 3.13 (95%CI: 2.7 to 3.6, p &lt; 0.0001), reaching the highest point when a value larger than 15 Ω was observed (99.9% of acute success). A significant trend was observed from lower to higher LI drop/τ values and a value greater than 0.65 Ω/s (best cut-off value on the basis of the ROC analysis) was significantly associated with successful RF delivery with an OR of 5.54 (95%CI: 4.31 to 7.11, p &lt; 0.0001). No complications occurred during and after procedures. At 1-year follow-up, the AF recurrence rate was 12% after the 90-day blanking period.

Conclusions
The magnitude and time-course of the LI drop during RF delivery were associated with effective lesion formation. This ablation strategy for PVI guided by LI technology proved safe and effective, and resulted in a very low rate of AF recurrence over 1-year follow-up.
Electrical cardioversion during cryoballoon pulmonary vein isolation predicts long-term ablation success in persistent atrial fibrillation
Authors: Boehmer A , Rothe M , Soether CM , Dobre BC , Abboud J , Kaess B , Ehrlich JR 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Cryoballoon pulmonary vein isolation (cryoPVI) is an established option for treatment of atrial fibrillation (AF) but many periprocedural events influencing long-term outcome and procedural safety of ablation remain unclear. In radiofrequency ablation studies, failure to convert to sinus rhythm and electrical cardioversion (ECV) have been associated with increased recurrence rates. In this context, the influence of ECV during cryoPVI on long-term ablation efficacy is unclear.

Objective
A prospective comparison of AF recurrence after cryoballoon ablation in patients who were in AF or atrial tachycardia at the beginning of cryoPVI requiring ECV during procedure with patients who underwent ablation therapy without ECV.

Methods
We analyzed consecutive patients who underwent cryoPVI in a single-center cohort between 2018 and 2020. Follow-up was performed at 3, 6, 12, 18 and 24 months after ablation. Primary endpoints were: symptomatic AF recurrence for efficacy and bleeding, phrenic nerve injury, stroke or death for safety.

Results
472 consecutive patients who underwent ablation in a single-center cohort were analysed. Mean follow-up time was 15 months. In 195 patients (74 paroxysmal AF vs. 121 persistent AF, age 69 ± 10 years, 57% male, CHA2DS2-VASc 2.6 ± 1.4) at least one ECV was performed following ablation, while no cardioversion was necessary in 277 patients (214 paroxysmal AF vs. 63 persistent AF, age 69 ± 10 years, 55% male, CHA2DS2-VASc 2.7 ± 1.5). After 24 months, primary efficacy endpoint occurrence was significantly higher in persistent AF requiring cardioversion during procedure than for persistent AF without cardioversion and paroxysmal AF with/ without cardioversion (56.1 % vs. 31.2%, 33.6%, 32.9%, log-rank p = 0.009, figure). Primary safety endpoint occurred in form of pericardial effusion or transient phrenic nerve injury in two patients in cardioversion group (1.0%) and three patients without cardioversion (1.1%). No deaths or strokes were observed in either group. Total procedure duration (55.6 ± 17min vs. 57.7 ± 15.9min, P = 0.17) and left-atrial dwell time (39.7 ± 14.9min vs. 42 ± 15.6min, P = 0.11) were similar.

Conclusion
In patients with persistent AF, the need for ECV during cryoPVI predicts a poorer long-term outcome during 2-year follow-up. Future studies should focus on this specific patient population. Abstract Figure.
Anticoagulant treatment status and outcomes of elderly non-valvular atrial fibrillation patients with a history of catheter ablation in Japan: subanalysis of the ANAFIE registry
Authors: Okumura K 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): Daiichi Sankyo Co., Ltd.

OnBehalf
ANAFIE Registry Group
Backgrounds
Benefits of catheter ablation (CA) have been shown for patients with atrial fibrillation (AF). However, data in elderly patients aged ≥75 years who have undergone CA for non-valvular AF (NVAF) are insufficient.
Purpose
The All Nippon Atrial Fibrillation In the Elderly (ANAFIE) Registry is a prospective, multicenter, observational study, which was designed to collect the real-world data on the clinical status and prognosis in 30,000 over Japanese patients (aged ≥75 years) with NVAF. This cross-sectional subanalysis of the ANAFIE registry assessed the 2-year outcomes and anticoagulant treatment in elderly NVAF patients with a history of CA.

Methods
A total of the 32,275 patients from the ANAFIE registry were divided into two groups by a history of CA: the CA and No-CA groups. Kaplan-Meier analysis was used to evaluate the annualized incidences of stroke/systemic embolic event (SEE), major bleeding, intracranial hemorrhage (ICH), heart failure requiring hospitalization (HF), and all-cause mortality. Hazard ratio (HR) for each event was analyzed using the Cox proportional-hazards model.

Results
Of all patients, 2,970 patients (9.2%) were included in the CA group and 29,305 (90.8%) were included in the No-CA group. The CA group had lower age (mean 78.9 vs 81.7 years), higher prevalence of paroxysmal AF (73.0 vs 39.0%), higher creatinine clearance (mean 53.1 vs 47.9 mL/min) and lower CHA2DS2-VASc (mean 4.2 vs 4.5) and HAS-BLED scores (mean 1.8 vs 1.9) than the No-CA group. Oral anticoagulants (OACs) were administered in 87.3% of the CA group (warfarin, 16.8%; direct OAC, 70.5%) and 92.9% of the No-CA group (warfarin, 26.4%; direct OAC, 66.5%). Compared with the No-CA group, the CA group had lower the annualized incidences (/100 patient-year [95%confidence intervals]) of stroke/SEE (0.74 [0.52, 0.96] vs 1.72 [1.61, 1.83]), major bleeding (0.63 [0.43, 0.84] vs 1.12 [1.03, 1.21]), ICH (0.49 [0.31, 0.67] vs 0.78 [0.71, 0.86]), HF (2.54 [2.12, 2.96] vs 4.44 [4.26, 4.62]), and all-cause mortality (1.45 [1.14, 1.77] vs 3.95 [3.78, 4.11]).
Conclusions
Elderly NVAF patients with a history of CA had lower adverse incidences compared with patients without a history of CA. A more optimal OAC therapy for elderly NVAF patients with a history of CA should be examined in the future.
Personalized atrial fibrillation ablation by tailoring ablation index to the left atrial wall thickness. the ablate by-law single center study
Authors: Teres C , Penela D , Soto-Iglesias D , Jauregui B , Ordonez A , Chauca A , Carreno-Lineros JM , Scherer C , Huguet M , Ramirez-Paesano C , Oller G , Panaro A , Carballo J , Ortiz-Perez JT , Berruezo A 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Dr Teres is funded by the research fellowship grant from the Swiss Heart Rhythm Foundation, Dr Carreno was funded was funded by a Scholarship from Sociedad Española de Cardiología (SEC).

Introduction
Left atrial wall thickness (LAWT) is a determinant of transmural lesion formation during atrial fibrillation (AF) ablation. The utility of ablation index (AI) to dose radiofrequency (RF) delivery for the reduction of AF recurrences has already been proven with a target AI ≥ 400 at the posterior wall and ≥550 at the anterior wall.

Objective
To determine if adapting AI to atrial wall thickness (AWT) is feasible, effective and safe during AF ablation.

Methods
Consecutive patients referred for a first PAF ablation. LAWT 3D-maps were obtained from multidetector computed tomography (MDCT) and integrated into the CARTO navigation system. LAWT maps were semi-automatically computed from the MDCT as the local distance between the LA endo and epicardium and categorized into 1mm-layers and AI was titrated to the LAWT, as follows: Thickness &lt; 1 mm (red): 300; 1-2 mm (yellow): 350; 2-3 mm (green): 400; 3-4 mm (blue): 450; &gt; 4 mm (purple): 450 (Figure). The ablation line was designed in a personalized fashion to avoid thicker regions. All ablation procedures were performed under general anesthesia with a high frequency low-volume ventilation. Primary endpoints were acute efficacy and safety, and freedom from AF recurrences. Follow-up (FU) was scheduled at 1, 3, 6, and every 6 months thereafter.

Results
90 patients [60 (67 %) male, age 58 ± 13 years] were included. Mean LAWT was 1.25 ± 0.62 mm. Mean AI was 366 ± 26 on the right pulmonary veins (RPVs) with a first-pass isolation in 84 (93%) patients and 380 ± 42 on the left pulmonary veins (LPVs) with first-pass in 87 (97%). Procedure time was 59 min [49-66]; RF time 14 min [12,5-16]; fluoroscopy time 0.7 min [0.5-1.4]. No major complication occurred. Eighty-six out of 90 (95.5%) patients were free of recurrence after a mean FU of 11 ± 4 months.

Conclusions
Personalized AF ablation, adapting the AI to LAWT allowed decreasing RF delivery, fluoroscopy and procedure time while obtaining a high rate of first-pass isolation. Lesion durability as estimated by freedom from AF recurrences was as high as in more demanding ablation protocols. Abstract Figure. Personalized protocol and results
Sex differences in mapping and rhythm outcomes of a repeat atrial fibrillation ablation
Authors: Pak HN , Park JW , Yang SY , Kim M , Yu HT , Kim TH , Uhm JS , Joung BY , Lee MH 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
The risk of procedure-related complications and rhythm outcomes differ between men and women after atrial fibrillation catheter ablation (AFCA). We evaluated whether consistent sex differences existed in mapping and rhythm outcomes in repeat ablation procedures.

Methods
Among 3,282 patients in the registry, we analysed 443 consecutive patients (24.6% female, 58.5 ± 10.3 years old, 61.5% paroxysmal AF) who underwent a second AFCA. We compared the clinical factors, mapping, left atrial (LA) pressure, complications, and long-term clinical recurrences after propensity score matching.

Results
The LA volume index (43.1 ± 18.6 vs. 35.8 ± 11.6 ml/m2, p &lt; 0.001) was higher, but LA dimension (40.0 ± 6.8 vs. 41.6 ± 6.3mm, p = 0.018), LA voltage (0.94 ± 0.55 vs. 1.20 ± 0.68 mV, p = 0.002), and pericardial fat volume (89.5 ± 43.1 vs. 122.1 ± 53.9 cm3, p &lt; 0.001) lower in women with a repeat ablation than in their male counterparts. The pulmonary vein (PV) reconnections were lower (58.7% vs. 74.9%, p = 0.001), but the proportion of extra-PV triggers (27.5% vs. 17.0%, p = 0.026) and elevated LA pulse pressures (79.7% vs. 63.7%, p = 0.019) was significantly higher in women than men. There was no significant sex difference in the procedure-related complication rate (4.6% vs. 4.2%, p = 0.791). During a 31(8∼60) month median follow-up, clinical recurrences were significantly higher in women after both the de novo procedure (log rank p = 0.039, antiarrhythmic drug [AAD]-free log rank p &lt; 0.001) and second procedure (log rank p = 0.006, AAD-free log rank p = 0.093). A female sex (HR 1.51 [1.06-2.15], p = 0.023), non-paroxysmal AF (HR 1.78 [1.30-2.34], p &lt; 0.010), and extra-PV triggers (HR 1.88 [1.28-2.75], p = 0.001) were independently associated with clinical recurrences after repeat procedures.

Conclusions
During the repeat AFCA procedures, PV reconnections were lower in women than men, and the existence of extra-PV triggers and an LA pressure elevation was more significant, which resulted in poor rhythm outcomes.
Catheter ablation versus antiarrhythmic drugs as first-line therapy for symptomatic atrial fibrillation: a systematic review and meta-analysis
Authors: Casula M , Pignalosa L , Fortuni F , Baldi E , Sanzo A , Savastano S , Petracci B , Vicentini A , Rordorf R 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
In patients with symptomatic atrial fibrillation (AF), current international guidelines favor the use of antiarrhythmic drugs (AAD) as initial therapy for the maintenance of sinus rhythm. Previous studies have compared catheter ablation for pulmonary vein isolation versus AAD in this clinical scenario but the best first-line therapeutic option in patients with symptomatic AF candidates for rhythm control strategy remains an open issue.
Aim
To compare efficacy and safety of catheter ablation versus AAD as first-line therapy in patients with symptomatic AF.

Methods
We searched electronic databases for randomized controlled trials (RCTs) comparing catheter ablation versus AAD as first-line therapy for symptomatic AF. The primary efficacy outcome was any recurrence of atrial tachyarrhythmias. The secondary efficacy outcomes were symptomatic arrhythmic recurrences. The safety outcomes were serious adverse events related to the therapeutic regimen. Outcome events were defined according to the definition used in each original study. The effect size was estimated using a random-effect model as risk ratio (RR) and relative 95% confidence interval (CI) with the statistical software Review Manager 5.3.

Results
Five RCTs counting 997 patients (503 treated with catheter ablation and 494 with AAD) were included in the analysis. Mean age was 57 ± 3 years, 30% were female. Mean left ventricle ejection fraction was 60%±4% and mean left atrial diameter was 40 mm ± 1 mm. At baseline 52% of patients were treated with a beta-blocker and 11% with a calcium channel blocker. In the catheter ablation group 258 patients (51%) underwent cryoablation and 245 (49%) radiofrequency ablation. Median follow-up was 12 months (IQR 12-24 months). Patients treated with catheter ablation had statistically significant lower risk of atrial tachyarrhythmias recurrences (RR 0.59; 95%CI 0.45-0.76; p &lt; 0.0001 – Figure A) and of symptomatic arrhythmia recurrences (RR 0.45; 95%CI 0.25-0.80; p = 0.007 – Figure B) compared with those treated with AAD. The risk of serious adverse events related to the therapeutic regimen did not differ significantly between patients undergoing catheter ablations and those treated with AAD (RR 0.85; 95%CI 0.45-1.59 – Figure C).

Conclusions
In patients with symptomatic AF, catheter ablation as first-line therapy is associated with a reduced risk of atrial tachyarrhythmias recurrences compared with AAD, without statistically significant differences in the risk of serious adverse events related to the treatment. Abstract Figure.
Artificial intelligence-predicted poor responders to catheter ablation for atrial fibrillation
Authors: Park JW , Kwon OS , Shim JM , Yu HT , Kim TH , Uhm JS , Kim JY , Choi JI , Joung BY , Lee MH , Kim YH , Pak HN 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Although atrial fibrillation (AF) catheter ablation is effective for rhythm control, in some patients it is hard to maintain sinus rhythm in spite of repeated AF catheter ablation (AFCA) procedures and anti-arrhythmic drugs (AADs). We explored the pre-procedural predictors for poor responders to AFCA and tested whether artificial intelligence (AI) assists the prediction of poor responders in the independent cohort by determining the invasive parameters.

Methods
Among 1,214 patients who underwent AFCA and regular rhythm follow-up for 56.2 ± 33.8 months (59 ± 11 years, 73.5% male, 68.6% paroxysmal AF), we differentiated 92 poor responders defined as those with sustained AF despite repeat AFCAs, AADs, or electrical cardioversion. Using the Youden index, we identified advanced LA remodeling with lower LA voltage under 1.109mV. AI model, which was derived from development cohort using medical record, was applied to predict LA voltage &lt;1.109mV in the independent cohort (n = 634, poor responders = 24) using a grad-cam score.

Results
The patients with lower LA voltage under 1.109mV showed significantly poorer rhythm outcomes (Log-rank p &lt; 0.001). We determined invasive parameter LA voltage by using the multiple variables (age, female sex, AF type, CHA2DS2VASc score, LA dimension, E/em, hemoglobin, PR interval) and achieved relatively good prediction power of AI for LA voltage &lt;1.109mV (AUC = 0.734, sensitivity 0.729, specificity 0.643) in the test cohort. In the independent cohort, the AI model showed good discrimination power for poor responders (AUC 0.751, p &lt; 0.001) by estimating LA voltage, which is an invasive variable. The patients with predicted lower LA voltage (grad-cam score &lt;0) showed poorer rhythm outcome after active rhythm control (Log-rank p &lt; 0.001)

Conclusions
The patients with advanced atrial remodeling with low LA voltage, which can be predicted by an AI, showed significantly higher recurrence of AF after AFCA with AADs or cardioversion. AI may assist to select these poor responder patients before the AFCA procedure. Abstract Figure.
General anaesthesia during radiofrequency ablation of atrial fibrillation is associated with improved procedural characteristics but with similar long-term outcomes: a single center study
Authors: Traykov V , Marchov D , Marinov M , Boychev D , Gelev V 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
General anaesthesia (GA) or conscious sedation can be used during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) based on physician’s and patient’s preference. Increasing number of centers include GA in their institutional protocols for RFCA of AF.

Purpose
The current study aims to compare real-world data on procedural characteristics, complication rate and procedural outcomes in patients undergoing RFCA of AF under GA or sedation at a single center.

Methods
A total of 167 patients (116 males, age 57.53 ± 9.78 years) with paroxysmal or persistent AF undergoing RFCA were studied retrospectively. Patients underwent RFCA under GA (108 patients, Group 1) provided by the anaesthesia team at our institution or under conscious sedation (59 patients, Group 2) guided by the operator using bolus doses of midazolam and fentanyl. We compared procedural time, fluoroscopy time, dose-area product (DAP), number of lesions and cumulative RF time between the two groups. We also analysed the complication rates and the long-term outcome in the two groups. Results are presented as mean ± SD or median (25th – 75th percentile).

Results
Groups 1 and 2 were comparable in terms of baseline clinical characteristics. Group 1 patients demonstrated significantly shorter procedural time as compared to Group 2: 149.52 ± 41.31 min vs. 208.23 ± 77.10 min, P &lt; 0.0005. Fluoroscopy time was also shorter in Group 1 24 (20-31.75) min compared to 36 (22.5-46.5) min in Group 2, P &lt; 0.0001. This corresponded to lower radiation dose expressed by DAP which was also significantly lower in Group 1 patients: 3230 (1660-6793.2) cGy/cm2 vs. 13880 (4215-21324) cGy/cm2 for Group 2, P &lt; 0.0001. Administration of GA during the procedure was associated with lower number of RF applications: 52.49 ± 19.36 in Group 1 vs. 68.33 ± 30.74 in Group 2, P = 0.0001. This corresponded with the lower cumulative RF time noted in the patients from Group 1: 2499.2 ± 824.17 sec vs. 3220 ± 1357.26 sec in Group 2, P &lt; 0.0001. Procedural complications occurred in 5 patients from Group 1 (4.6%) and in 8 patients (13.6%) in Group 2, P = 0.066. There was a single case of atrioesophageal fistula in a patient from Group 1. After a median follow-up of 20 (8-41) months 75% of the patients from both Group 1 and Group 2 were arrhythmia-free following 1.5 ± 0.68 procedures (P = 1.0).

Conclusion
Performing RFCA of AF under GA is associated with shorter procedural time, lower radiation dose and with the need for less energy application. This does not result in significantly lower complication rates. Long-term procedural outcomes do not seem to be affected by the use of GA.
Fluoroless ablation of atrial fibrillation using intracardiac ultrasound integrated with 3D electroanatomical mapping system
Authors: Antolic B , Jan M , Vrbajnscak M , Zizek D , Kajdic N 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Intracardiac echocardiography (ICE) is gaining increasingly wider adoption in interventional electrophysiology (EP) and represents an all-round tool for ablation of atrial fibrillation (AF). The key upgrade to the usefulness of ICE is its integration into three-dimensional (3D) electroanatomic mapping (EAM) system (ICE/EAM automatic integration system).

Purpose
The aim of this single-centre retrospective study was to evaluate feasibility, safety and acute efficacy of ICE/EAM automatic integration system guided fluoroless ablation of AF.

Methods
Patients with symptomatic paroxysmal or persistent AF referred for first pulmonary vein isolation (PVI) radiofrequency catheter ablation (RFCA) from September 2017 to August 2020 were included in the study. Those who underwent additional ablations for concomitant arrhythmias were excluded from statistical analysis. All procedures were performed without the use of fluoroscopy. A detailed 3D virtual anatomy of the left atrium (LA) and structures relevant to AF ablation was constructed from ultrasound contours obtained with ICE probe inside the LA. Pulmonary veins (PVs) and antral regions were additionally mapped with fast anatomical mapping. PVI was performed with contact force (CF) sensing catheter. Procedural endpoint was successful PVI.

Results
A total of 56 patients underwent RFCA (35.7% females, median age 62.7 years, 53.6% paroxysmal AF). Acute PVI was achieved in all patients (100%). Adverse events were detected in two patients (3.6%). The median procedure duration was 110.5 min (IQR 100.0-133.8). First-pass isolation was achieved in 50/56 LPVs (89.3%) and in 44/56 RPVs (78.6%). In patients where first-pass isolation was no achieved, intravenous carina had to be ablated in 3/6 (50%) of LPVs and 9/12 (75%) of RPVs.

Conclusions
Flouroless PVI using ICE/EAM automatic integration system is feasible, safe and acutely effective. We achieved high rate of first-pass isolation.