bluuebunny/crossref_metadata_2025_split huggingface dataset:
High density catheter approach with liveview dynamic display improves procedural efficiency of atrial fibrillation ablation
Authors: Di Cori A , Giannotti Santoro M , Parollo M , Della Volpe S , Mazzocchetti L , Barletta V , Segreti L , Viani S , De Lucia R , Canu A , Grifoni G , Soldati E , Bongiorni M G , Zucchelli G 
Published: October 2022

Abstract

Introduction
PVI isolation confirmation after RF ablation is often time-consuming, especially in case of a single transeptal catheter approach into the left atrium. A novel Live View (LV) dynamic display mapping software, utilized in combination with the High Density (HD) Grid mapping catheter, allows to display beat-to-beat, dynamic regional mapping data.

Purpose
We evaluated the feasibility and the procedural impact of a procedural left atrial workflow with a single transeptal-single HD catheter analysis, incorporating the LV Mapping Software for the assessment of PVI after ablation.

Methods
Paroxysmal and persistent AF patients scheduled for AF ablation were prospectively enrolled. All patients underwent only PVI under LSI guidance (LSI between 5.5 and 6 anteriorly; LSI between 4.5 and 5 posteriorly) with a point by point strategy and an inter-lesion distance &lt;6 mm. According to the HD mapping strategy used to confirm entrance block after first pass PVI, patients were divided in two groups. The HD-LV Group included patients mapped with the HD-LV software and the HD-standard mapping (SM) group included patients which received a conventional PVI validation with a static voltage/activation map. Left PVI was evaluated during distal coronary sinus pacing and right PVI during sinus rhythm. Exit block was also evaluated to confirm bidirectional block. Procedural efficiency parameters were compared between groups.

Results
Forty-six patients with AF (58% paroxysmal) were prospectively enrolled. Twenty-five patients were included in the HD-LV Group and 21 in the HD-SM Group. PVI was successful in all patients. LV dynamic display analysis was feasible in all patients and allowed a simple and fast validation of right and left PVI, without the necessity of introducing a second catheter into the left atrium. The split screen modality, with a dynamic activation map on the left and a dynamic voltage map on the right, allowed to switch from CS pacing to sinus rhythm without the necessity of a remap. The overall mapping time (27±10 vs 37±14 min, p=0.006), total procedure time (138±33 vs 178±50 min, p=0.006) and fluoroscopy time (14±5.3 vs 23±11 min, p=0.006) were significantly lower in the HD-LV Group. No complication was seen in either group.

Conclusions
A simplified clinical utilization of LiveView dynamic display with a single transeptal-single HD catheter approach is feasible and efficient after PVI, potentially simplifying the procedural workflow. A real-time dynamic mapping in daily practice may further enhance the clinical benefits of HD mapping during radiofrequency (RF) catheter ablation procedures.

Funding Acknowledgement
Type of funding sources: None.
Predictors of AF recurrence in patients with paroxysmal AF undergoing catheter ablation: new predictors coming?
Authors: Ribeiro Silva M , Ribeiro Queiros P , Santos Silva G , Teixeira R , Fernandes S , Almeida J , Fonseca P , Oliveira M , Goncalves H , Rodrigues A , Primo J , Fontes-Carvalho R 
Published: October 2022

Abstract

Introduction
Recurrence of atrial fibrillation (AF) after catheter ablation (CA) is estimated to be between 20% and 45% and the prediction of recurrence AF in patients (pts) with paroxysmal AF undergoing CA remains challenging.

Purpose
To determine the clinical and procedural predictors of recurrence AF after CA in pts with paroxysmal AF.

Methods
Single-centre retrospective study that included all pts with paroxysmal AF who underwent AF CA between 2017 and 2019. Ablation procedures included radiofrequency and second-generation cryoballoon CA. All pts underwent cardiac computed tomography prior the procedure. AF recurrence was defined as any recurrence of AF, atrial flutter or atrial tachycardia &gt;30 seconds (recorded in 12-lead electrocardiogram or Holter) after 90 days of CA. The independent association between clinical and procedural variables and AF recurrence was evaluated with Cox regression analysis.

Results
We included 351 pts, 63,5% male and with a mean age of 57,1±11,4 years. CHADSVASCscore ≥2 points were present in 43,7% of the pts, median duration of AF prior the intervention was 3 years (IQR 1–6) and most pts were treated with some antiarrhythmic drug at the time of CA (56,9%). Overall, median follow-up was 27 months (IQR 19–39).
AF recurrence was present in 96 pts (27,4%), on average, 15,2±10,4 months after CA.
Univariate logistic regression identified female gender, thyroid disease, left atrium (LA) enlargement (defined as LA indexed volume &gt;34 mL/m2 or LA diameter &gt;38mm for female or &gt;40mm for male), coronary calcium score &gt;100, epicardial adipose tissue volume, number of previous electric cardioversions, treatment with antiarrhythmic drugs prior CA and the extent of CA (only pulmonary vein isolation (PVI) or PVI and ablation of other lesions) as predictors of recurrence AF after CA in pts with paroxysmal AF (p&lt;0,05 for all).
Cox regression analysis identified female gender (OR 1,615, 95% CI 1,005–2,597; p=0,008), LA enlargement (OR 2,084, 95% CI 1,207–3,596; p=0,008) and coronary calcium score &gt;100 (OR 1,958, 95% CI 1,133–3,385; p=0,016) as independent predictors of AF recurrence.

Conclusions
In our cohort, AF recurrence was significantly higher in pts with LA enlargement, with coronary calcium score &gt;100 and female gender pts.

Funding Acknowledgement
Type of funding sources: None.
Significant procedure length reduction when utilizing active esophageal cooling – a six-year single center study
Authors: Joseph C , Willms D , Francisco G , Ruppert A , Athill C 
Published: October 2022

Abstract

Background
A number of factors can influence procedure duration of left atrial ablation for the treatment of atrial fibrillation (AF). In addition to ablation techniques, the use of auxiliary tools such as intraoperative fluoroscopy and luminal esophageal temperature (LET) monitoring may impact procedure duration. However, unlike recent trends toward zero-fluoroscopy procedures, there has not been a widespread transition to alternative means of esophageal protection. Multi sensor LET monitoring leads to frequent pauses during ablations when dangerous esophageal temperatures have been reached. Although an increased risk of esophageal injury when utilizing LET monitoring as compared to active esophageal cooling has been suggested in recent studies, the degree to which LET monitoring impacts procedure duration has not been well documented. Consequently, we aimed to compare procedure duration in a large single center before and after active esophageal cooling was implemented in place of LET monitoring.

Objective
Review procedural timing data at a single large hospital before and after the implementation of active esophageal cooling in place of LET monitoring, and compare differences in procedure duration.

Methods
Using an existing hospital registry of ablation procedures, we obtained procedure durations for left atrial ablations for AF before and after the implementation of active esophageal cooling into the hospital protocol. Data was collected with IRB approval from a single hospital from January 2015 through November 2021. Prior to September 2018, multi-sensor LET monitoring was utilized in all patients, whereas all patients afterwards were treated with active esophageal cooling.

Results
Data was analyzed from a total of 412 patients. LET monitoring was utilized with 176 patients, while active esophageal cooling was utilized with 236 patients. In the LET monitored group the median procedure length was 191 minutes with an interquartile range (IQR) of 91 minutes. In the actively cooled group, the median procedure length was 147 minutes with an IQR of 61 minutes. This represents a median difference of 44 minutes, or 23% of total procedure time (p&lt;0.001).

Conclusion
When compared to LET monitoring, the use of active esophageal cooling is associated with a significant time savings in PVI procedures.

Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): Attune Medical
Prediction of recurrence after catheter ablation for atrial fibrillation using left atrial morphology on preprocedural computed tomography: application of radiomics
Authors: Hirota N , Suzuki S , Arita T , Yagi N , Otsuka T , Yamashita T 
Published: October 2022

Abstract

Background
Radiomics is a comprehensive analysis methodology of medical image and involves the extraction of numerous features from standard imaging. Its usefulness has been reported mainly in the field of cancer for diagnosis and prediction of prognosis. In the territory of cardiac imaging, several reports have investigated the utility of radiomics for classifying the risk of prognosis in coronary artery disease, and few practical applications have been reported for patients with atrial fibrillation (AF) who underwent pulmonary vein isolation (PVI). Although the left atrial morphology can affect the clinical course after the PVI procedure, it is unclear whether the radiomics feature values of the left atrial morphology on cardiac computed tomography (CT) is useful for predicting the AF recurrence after PVI.

Purpose
To predict the recurrence of AF after PVI using the radiomics feature values of the left atrial morphology on cardiac computed tomography (CT).

Methods
We analyzed 525 consecutive three-dimensional cardiac CT in patients with atrial fibrillation who underwent PVI from 2018 to 2019 in our institute. After marking the region of interest on left atrium (including the root of pulmonary veins) semiautomatically, 107 radiomics feature values were obtained by Python program. After excluding the parameters having collinearity or with low predictive capability for the recurrence of AF after PVI, 42 parameters were applied to the final prediction model. Two prediction models were constructed by multivariate Cox regression analysis and machine learning model by support vector machine algorithm.

Results
The area under the curve (AUC) for predicting the recurrence of AF was 0.815 for the multivariate Cox regression model and 0.826 for the machine learning model by support vector machine.

Conclusion
The radiomics feature values on preprocedural cardiac CT could be helpful for predicting the recurrence of AF after PVI. Since radiomics feature analysis yields a huge number of numerical values representing the left atrial morphology in a reproducible manner, it would provide a new direction to construct a good prediction model using machine learning including artificial intelligence out of a routine cardiac CT scan.

Funding Acknowledgement
Type of funding sources: None.
Ablation of residual potentials along the circumferential line reduces acute reconnection in patients undergoing pulmonary vein isolation
Authors: Tzeis S , Kojic D , Manola S , Brusich S , Pernat A , Asvestas D , Xenos T , Tomovic M , Cubranic Z , Rauber M , Pavlovic N 
Published: October 2022

Abstract

Introduction
Acute pulmonary vein (PV) reconnection is frequently encountered in patients with atrial fibrillation (AF) subjected to PV isolation (PVI).

Purpose
In this prospective, multicenter, randomized study, we investigated whether the identification and ablation of sites along the circumferential line with specific electrogram criteria indicative of nontrasmurality, after initial achievement of PVI, reduces acute PV reconnection rate.

Methods
Patients referred for AF ablation at five European centers were enrolled. PVI with antral circumferential isolation of ipsilateral PVs was performed using a contact force sensing ablation catheter delivering 35–40W at the anterior/superior and 30W at the posterior wall with target ablation index of 550 at the anterior wall/roof and 400 at the posterior/inferior segments. Following PVI, mapping with the ablation catheter was performed to identify residual potentials (RP) along the ablation line, defined as bipolar amplitude ≥0.2 mV or 0.1–0.19 mV combined with negative component of the unipolar electrogram as recorded by the 3D mapping system. Ipsilateral PV sets with RPs were randomized to either no further ablation (Group B) or to additional ablation of RPs (Group C). The primary study endpoint was defined as spontaneous or adenosine-mediated recovery of conduction after 30-minute waiting period which was also evaluated in ipsilateral PV sets without residual potentials (Group A).

Results
In total, 109 patients (59.3±10.6 years, 47% hypertension, 9.3% diabetes, left atrial diameter 39.1±4.6mm) were enrolled in the study. After initial isolation of 194 PV pairs, 98 PV pairs had no RPs (Group A) while the remaining 96 with RPs were randomized to either Group B or C (48 PV pairs each). The number of sites with RPs did not differ between groups B and C (4.1±2.5 vs 4.7±3.2, p=0.27). The occurrence of the primary endpoint in Group A was 7.1%. Ablation of residual potentials resulted in significant reduction of spontaneous or adenosine mediated reconnection (14.6% vs 47.9%, p&lt;0.001).

Conclusion
Following initial PVI achievement, ablation of RPs along the antral circumferential line reduces spontaneous or adenosine-mediated acute PV reconnection rate in patients undergoing first-time AF ablation. Therefore, scanning of the PVI line in search of weak links with specific electrogram criteria indicative of nontrasmurality, and subsequent deployment of bonus lesions, could represent a convenient and practical way to reduce acute PV reconnection. Further studies are required to assess long term effects on AF recurrence rates.

Funding Acknowledgement
Type of funding sources: None.
Spatiotemporal signatures of response to atrial fibrillation ablation
Authors: Ganesan P , Rogers A J , Deb B , Feng R , Rodrigo M , Ruiperez-Campillo S , Tjong F V , Bhatia N , Clopton P , Rappel W J , Narayan S M 
Published: October 2022

Abstract

Background
Atrial fibrillation (AF) can have organized regions, in the form of consistent dominant frequency sites, focal or reentrant sites, but it is unclear how these overlap with or differ from focal atrial tachycardias (AT) or potential drivers. We set out to develop an intuitive method based on fundamental electrogram shape and timing to separate types of AF.

Objective
To test the hypothesis that spatial regions of electrogram (EGM) in AF that show similar shapes over time based on cross-correlation analysis may separate patients with differing response to ablation.

Methods
We recruited N=133 patients (63.8±12.1 Y, 32% women), (i) N=10 had AT, (ii) N=122 AF that was or was not terminated by ablation, and (iii) N=1 pacing. All patients had left atrial mapping by 64 pole baskets. We applied repetitive activity (REACT) mapping that correlates EGMs in contiguous 2x2 regions (Fig. 1A) over 4sec. To calibrate REACT, we introduced simulated variations in shape (gaussian noise) and timing (gaussian delay) to pacing EGMs and computed nomograph over 100 random trials (Fig. 1C).

Results
Fig. 1B shows that REACT in a 71-year-old man with AT is more organized than in a 65 YO man with AF (100% vs 40% mapped field). Overall, REACT was higher in AT than AF (0.63±0.15 vs 0.36±0.22, p&lt;0.001). There were 24 cases in which global REACT between AF and AT groups had the overlapping range of values, indicating organized “islands” in AF analogous to AT. From nomograph in Fig. 1C we identified that this overlap reflects 15 ms variation in cycle length and 20% variation in EGM shape (labelled “x” in Fig. 1C).

Conclusion
Basic electrogram properties in AF of similar shapes in spatial areas over time can separate response to ablation and may represent “islands” of AT. Future studies should investigate the mechanisms for such islands and whether they may be targeted for therapy.

Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): US National Institutes of Health
High epicardial fat volume is associated with atrial fibrillation recurrences after catheter ablation
Authors: Herman R , Hlivak P , Bernat V , Svetlosak M , Demolder A , Palus T , Urban L , Hatala R 
Published: October 2022

Abstract

Background
Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation therapy for atrial fibrillation (AF). However, even with important technological improvements, AF recurrences are common in long-term follow-up. Recently, epicardial fat tissue (EFT) has been proposed as a potential AF modulator promoting and sustaining atrial arrhythmogenic milieu.

Aim
In this retrospective single-centre study, we sought to evaluate the association between CT-quantified EFT volume and long-term primary PVI outcome assed by means of continuous ECG monitoring with implantable loop recorders (ILR) in paroxysmal AF patients.

Methods
A cohort of 92 patients (median age 60.2 [IQR 51.9–64.0]; 74% male) with paroxysmal AF (a single persistent AF episode was accepted) undergoing catheter ablation targeted at PVI was analysed. Prior to CA all patients underwent cardiac CT imaging with subsequent implantation of implantable loop recorder (ILR). Radiofrequency CA ablation with electro-anatomical mapping for PVI was used in 79 patients, balloon cryoablation was used in 13 patients. Verified complete PVI was defined as procedural endpoint. EFT volume was semi-automatically segmented and quantified on contrast enhanced CT studies. AF recurrence, defined as AF burden &gt;0.1% after the blanking period (90 days), was continuously assessed by ILR. Kaplan-Meier analysis of AF recurrence-free survival at 1-year, 2-year and 3-year follow-up periods compared patients stratified into EFT volume tertiles.

Results
During a median follow-up of 52.6 months [IQR 43–64], AF recurrence was detected in 58 (63%) patients, 29 (50%) of them underwent a repeat ablation. Patients in high, mid, and low total EFT volume tertiles had a median time to late AF recurrence of 154, 373, and 284 days (Fig. 1A). At a 1-year follow-up, patients in the high EFT volume tertile had the worst AF ablation outcome (p=0.023). However, this difference gradually faded-out and became non-significant at 2 and 3 years. ROC analysis revealed an EFT of 95 ml as an optimal cut-off (p=0.002) for expected arrhythmia recurrence post acutely successful PVI (Fig. 1B).

Conclusion
EFT volume quantification in a relatively homogenous, continuously monitored cohort of patients undergoing catheter ablation for paroxysmal AF revealed a significant association between AF recurrence at 1 year post ablation and volume of epicardial fat. These results suggest a possible role of epicardial adipose tissue as an adverse pro-fibrillatory factor. Identified EFT volume cut-offs have to be validated prospectively on a larger and balanced patient population.

Funding Acknowledgement
Type of funding sources: None.
Electrophysiological insights into left atrial conduction times and regional velocities in atrial fibrillation patients with and without fibrotic atrial cardiomyopathy
Authors: Heil E , Gerds-Li J H , Keznickl-Pulst J , Furundzija V , Hohendanner F , Pieske B , Schoeppenthau D 
Published: October 2022

Abstract

Background
Although considerable progress has been made in understanding the process of arrhythmogenesis in atrial fibrillation (AF) patients and the role of atrial substrate, little is known about atrial conduction characteristics in different grades of fibrotic atrial cardiomyopathy (FACM) and specific left atrial (LA) regions.

Purpose
The aim of this study was to evaluate left atrial conduction times (LACT) and -velocities (CV) in electroanatomical high density maps during sinus rhythm in AF patients with and without signs of atrial fibrosis.

Methods
Before radiofrequency catheter ablation electroanatomical high density mapping was performed in 41 AF patients (n=38 persistent, n=3 paroxysmal) using a 10-polar circular mapping catheter and the CARTO3 V7 navigation system (Biosense Webster, Diamond Bar, CA). We evaluated the size of low voltage areas (LVA ≤0.5mV), LACTs and local CVs at the anterior and posterior wall in low voltage areas and normal voltage areas (NVA ≥1.5mV). The latter were specifically calculated in the direction of wave-front propagation (coherent algorithm) by using 3-dimensional coordinates and local activation times of triads of sites.

Results
20 FACM and 21 non-FACM maps were analysed (1823±1031 points, n=16 low grade FACM I+II, n=4 high grade FACM III+IV, EF 57.24±6,18%, LAVI 43.01±15,63 ml/m2). The mean total size of LVA in FACM patients was 12.06 cm2 (anterior wall 9.51 cm2, posterior wall 2.55 cm2). LACT was 109.15±25.30 ms in our AF population, whereby LACT was shown to be longer (118.79ms, +18%) in FACM patients compared to patients without substrate (100.40 ms, p=0.01), particularly pronounced in high grade FACM (III–IV) (146 ms, +46%, p=0.001). The extension of LVA fairly strong correlated with LACT duration (Spearman ρ= 0.76). Conduction velocities in LVA revealed significantly lower (−55%) than those in NVA (0.61±0.11m/s vs. 1.34±0.30m/s, p=0.000). When comparing the anterior to the posterior wall, anterior conduction appeared slower than posterior conduction, which was significant in NVA (−12%, 1.02 vs. 1.16 m/s, p=0.0053) and failed to reach statistical significance in LVA (−11.6%, 0.61 vs. 0.069 m/s, p=0.39). See Figure 1 and Table 1 for more clinical and electrophysiological characteristics in FACM vs. non FACM patients.

Conclusion
Total LACT is significantly prolonged in FACM patients and seems to correlate with LVA size. Compared to areas with a normal bipolar voltage (≥1.5mV) LVAs (≤0.5mV) show a 55% CV reduction. Furthermore, regional CVs were shown to differ between the anterior and the posterior LA wall. Those findings might have an impact on developing substrate-based ablation strategies in catheter ablation of FACM patients.

Funding Acknowledgement
Type of funding sources: None.