scholarly journals The industrialization of ablation: a highly standardized and reproducible workflow for radiofrequency ablation of atrial fibrillation

2019 ◽  
Vol 59 (1) ◽  
pp. 21-27
Author(s):  
Tom De Potter ◽  
Tina D. Hunter ◽  
Lee Ming Boo ◽  
Sofia Chatzikyriakou ◽  
Teresa Strisciuglio ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Pulmonary Veins ◽  
High Volume ◽  
Posterior Wall ◽  
Anterior Wall ◽  
Atrial Arrhythmia ◽  
Af Ablation ◽  
Ablation Index ◽  
Effectiveness Endpoint

Abstract Background or Purpose The purpose of this analysis was to report on efficacy of a standardized workflow for atrial fibrillation (AF) ablation using technology advances such as 3D imaging and contact force sensing in a real-world setting. Methods Consecutive AF ablations from 2014 to 2015 at a high-volume site in Belgium were included. The workflow consisted of a pre-specified procedure sequence including 3D modeling followed by radiofrequency encircling of the pulmonary veins (25 W posterior wall, 35 W anterior wall) with a THERMOCOOL SMARTTOUCH® Catheter guided by CARTO VISITAG™ Module (2.5 mm/5 s stability, 50% > 7 g) and ablation index (targets: 550 anterior wall, 400 posterior wall). Efficiency endpoints were procedure time, fluoroscopy time, and radiation dose. The primary effectiveness endpoint was freedom from atrial arrhythmia recurrence. Results A total of 605 paroxysmal AF (PAF) and 182 persistent AF (PsAF) patients were followed for 436 ± 199 days. Mean procedure times were short (PAF: 96.1 ± 26.2 min; PsAF: 109.2 ± 35.6 min) with most procedures (90.6% PAF; 81.3% PsAF) completed in ≤ 120 min. Minimal fluoroscopy was utilized (PAF: 6.1 ± 3.8 min, 5.9 ± 3.4 Gy*cm2; PsAF: 6.9 ± 4.7 min, 7.4 ± 4.9 Gy*cm2). Freedom from atrial arrhythmia recurrence was higher for PAF than PsAF patients (OR: 2.0, 95% CI: 1.4–2.9, p = 0.0003), but adjusted mean rates were high in both groups (81.0% vs. 67.9%). Rates were adjusted for prior ablation and age (at 65 years). Conclusion AF ablation using a standardized workflow resulted in low procedure times and variability, with minimal fluoroscopy exposure. Long-term freedom from atrial arrhythmia recurrence was high in both PAF and PsAF populations.

P956Improved quality of life and symptomatic atrial fibrillation reduction in patients treated with a standardized ablation index workflow

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
D Gupta ◽  
J Vijgen ◽  
T De Potter ◽  
D Scherr ◽  
H Van Herendael ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Atrial Fibrillation ◽  
Posterior Wall ◽  
Anterior Wall ◽  
Atrial Arrhythmia ◽  
Meaningful Improvement ◽  
Score Improvement ◽  
Ablation Index ◽  
Patient Reported

Abstract Background/Introduction The use of a standardized ‘CLOSE’ ablation workflow for pulmonary vein isolation (PVI), with defined inter-tag distance (ITD) with targeted ablation index (AI) values, has been shown in single centre reports to result in good outcomes. The effect of this approach on patients’ quality of life (QoL) has not been studied. Purpose To evaluate the effects of paroxysmal atrial fibrillation (PAF) ablation by the CLOSE workflow on QoL and symptomatic AF reduction in the multicenter VISTAX study. Methods 329 patients with PAF (61.5% male, 61.3 ± 10.1 year) were treated at 17 European centres by point-by-point radiofrequency ablation using the CLOSE protocol to achieve PVI.  An ITD ≤6mm and AI values of ≥400 on the posterior wall and ≥550 on the anterior wall were targeted. The AI value on the posterior wall was lowered as per investigator discretion in case of safety concerns. Patients were monitored for atrial arrhythmia recurrences via weekly and symptom-activated transtelephonic monitoring (TTM), for 12 months post procedure. Patients completed an Atrial Fibrillation Effect on Quality-of-life (AFEQT) questionnaire at their baseline and 12-month follow up visits. Results Majority (83.3% [274/329]) of patients experienced freedom from symptomatic atrial recurrence through 12 months. Of the 70 documented recurrences, 34 (49%) were documented by trans-telephonic monitoring only. All domains captured on the AFEQT questionnaire showed improvement with the overall score improving by 25.7, which exceeded the threshold of clinically meaningful improvement (±5) (Table). Patient reported most improvements in PAF control and symptoms relieved. The overall AFEQT score improvement was seen both in patients with or without documented atrial arrhythmia recurrence, with improvement by 21.5 and 26.8, respectively. Conclusion PAF ablation using a standardized CLOSE workflow resulted in consistent improvements in QoL. The improved QoL was observed regardless of atrial arrhythmia recurrence likely reflecting the low residual arrhythmia burden in patients with documented recurrence identified only on TTM. AFEQT Scores Through 12 Months AFEQT Domain Baseline 12 Months Change from Baseline* Daily Activities 59.2 85.3 26.0 Treatment Concerns 62.2 88.1 26.0 Controlling PAF 50.2 87.8 37.5 Symptoms 63.7 89.0 25.1 Symptoms Relieved 52.0 88.4 36.3 Overall AFEQT Score 61.3 87.2 25.7 *only includes patients who completed both baseline and 12 month AFEQT questionnaire

1242The flexibility, ease of using, and leaving curve of a standardized ablation index workflow for catheter ablation of paroxysmal atrial fibrillation

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
D Gupta ◽  
J Vijgen ◽  
T De Potter ◽  
D Scherr ◽  
H Van Herendael ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Learning Curve ◽  
Paroxysmal Atrial Fibrillation ◽  
Clinical Success ◽  
Posterior Wall ◽  
Learning Curves ◽  
Atrial Arrhythmia ◽  
Ablation Index ◽  
First Pass

Abstract Background/Introduction The ‘CLOSE’ protocol, incorporating standardized ablation index (AI) targets in conjunction with defined inter-tag distance (ITD) has been shown to improve the acute and long-term success of pulmonary vein isolation (PVI) when treating paroxysmal atrial fibrillation (PAF). The reproducibility and learning curve for this protocol has not been studied. Purpose To assess the acute and long-term efficacy of CLOSE PVI across multiple operators (n = 37) in the 17-centre European study ‘VISTAX’. Methods 329 patients with PAF (61.8% male, 61.3 ± 10.1 years) underwent PVI according to the CLOSE protocol, with target AI values for each lesion of ≥400 on the posterior wall and ≥550 on the anterior wall, and target ITD of ≤6mm. Each 3-dimensional electroanatomic map was evaluated at a core lab where adherence to each of these criteria was assessed. 281/329 patients (85.1%) fulfilled all standardized workflow requirements and were adjudicated as having their PVI per-protocol (PP). First pass PVI and acute effectiveness (adenosine-proof first pass PVI at 30-minute challenge) were recorded. Clinical effectiveness was assessed as freedom from atrial arrhythmia recurrence through 12 months recorded via transtelephonic monitoring (weekly and symptomatically), in addition to holter and electrocardiogram monitoring during 3,6,12 month follow up visits. Learning curve analysis was evaluated on all investigators. Results First pass PVI rates were similar in the overall (86%) and PP cohorts (85%), as was acute effectiveness (82% in both cohorts). Freedom from atrial arrhythmia at 12 months too was identical for both cohorts (79%). Total procedure time and total ablation time decreased by an average 8 minutes and 10 minutes respectively after the first procedure and then showed further steady decreases over the number of ablations performed by the investigator (Figure).  The procedural efficiencies and clinical success were reproducible across different centers. No significant deviations were found from individual sites. Conclusion The standardized CLOSE workflow is reproducible across centres, and is ‘forgiving’ without impacting on high efficacy of almost 80%. The learning curve is short, suggesting that the excellent clinical results can be replicated widely and easily. Abstract Figure. Learning Curves- Procedure & Ablation

Abstract 2753: The Relationship Between Pulmonary Vein Antrum Scarring Following Atrial Fibrillation Ablation and Procedural Success: Does Pulmonary Vein Isolation Matter?

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Troy J Badger ◽  
Robert S Oakes ◽  
Akram Shabaan ◽  
Nazem W Akoum ◽  
Nathan M Segerson ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Pulmonary Vein ◽  
Pulmonary Veins ◽  
Posterior Wall ◽  
Kaplan Meier ◽  
Number Of Patients ◽  
Procedural Success ◽  
The Relationship ◽  
Af Recurrence

Background. A mechanism of atrial fibrillation (AF) recurrence following ablation may be incomplete pulmonary vein antrum (PVA) scarring that allows for conduction between the pulmonary veins (PV) and the left atrium (LA). We report the relationship between circumferential PV scarring detected by delayed enhancement MRI (DE-MRI) and AF recurrence following PVAI. Methods. Eighty-six patients presenting for PVAI underwent DE-MRI 3 months post ablation. Circumferential ablation with posterior wall debulking was performed in all patients. PV ostia were marked on 3D images generated from the MRI data and assessed by consensus of two independent reviewers for the extent of scarring. Complete PVA scarring was defined as a continuous ring of enhancement surrounding the PVA. For patients with incomplete scarring, the degree of scarring was estimated. Results. The figure shows two patients from the cohort, Patient 1 exhibits successful scarring of all PVA. Patient 2 shows scarring of 1 PVA. At three months post ablation, complete circumferential lesion was seen on 131/335 PVA (39.1%). Complete scarring of 4 PVA was seen in 9 patients (10.5%), scarring of 3 PVA in 11 patients (12.8%) and scarring of 2 PVA was seen in 17 patients (19.8). Twenty-nine patients (33.7%) exhibited complete scarring in 1 PVA while 20 patients (23.3%) exhibited scarring in 0 PVA. Kaplan Meier analysis (Figure [E] ), suggests that PVA isolation may be important for long-term procedural success. Conclusion: Complete pulmonary vein antrum scarring exists in a very limited number of patients, despite its apparent importance for long-term procedural success.

scholarly journals Redo ablation for atrial fibrillation recurrence post radiofrequency or cryoballoon ablation: a high volume single-centre experience

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
M Ribeiro Da Silva ◽  
G Santos Silva ◽  
P Ribeiro Queiros ◽  
R Teixeira ◽  
J Almeida ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Pulmonary Veins ◽  
High Volume ◽  
Cryoballoon Ablation ◽  
Single Centre ◽  
Electrophysiologic Study ◽  
Electroanatomic Mapping System ◽  
Af Ablation ◽  
Funding Sources ◽  
Time To Recurrence

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Atrial fibrillation (AF) ablation is a well-established procedure for the treatment of AF. The cornerstone of AF ablation is the complete and durable isolation of pulmonary veins (PV) through radiofrequency (RF) or cryoballoon (CB) ablation. However, PVI durability between RF or CB was not yet established, as reablation strategy and outcomes in patients (pt) undergoing a redo ablation. Purpose To compare RF versus CB regarding PVI status, reablation procedure and outcomes in pts undergoing a second procedure. Methods Single-centre retrospective study of consecutive pts who underwent a redo between 2016 and 2020. PVI status was assessed during electrophysiologic study with electroanatomic mapping system. Index procedures included second generation CB, conventional RF before 2018 and CLOSE protocol guided RF ablation after 2018. We assessed time-to-redo, number and location of reconnected PVs, procedural characteristics, acute and long-term outcomes between RF and CB index PVI. Results Seventy-four (55 RF and 19 CB) pts were included, 68,9% were male, most pts had paroxysmal AF (71,6%) and a mean CHA2DS2-VASc score of 1,14 ± 1,0. No statistically significant differences were noticed in clinical and echocardiographic characteristics between pts within RF or CB cohorts. Median time to reablation was significantly longer in the RF cohort (38,6 months ±33,6) compared to CB (17,0 months ±9,5) (p = 0,014). The number of reconnected PV was higher in CB than the RF cohort, although not significant (2,37 ±1,2 vs 1,75 ±1,4;p = 0,080). Right inferior PV was significantly more reconnected in pts within the CB compared to RF group (73,7% vs 45,6%;p = 0,034), without differences in the other PV reconnection rates. Regarding reablation procedure, all pts were submitted to RF-redo. Fluoroscopy time was shorter for CB than RF cohort (7,4 ±2,9 vs 13,3 ±8,4;p = 0,002). There were no significant differences between the type of reablation (PVI only vs PVI plus other lesions or cavotricuspid isthmus ablation), with no difference in overall acute success. After the redo procedure, no differences were observed in recurrence rate in the blanking period and after 91 days from reablation. Nevertheless, time-to-recurrence (>91 days) was longer for RF than CB group (13,4 months ±10,7 vs 4,3 months ±1,5;p = 0,016). There were 2 pts in the RF group that were submitted to a third ablation procedure (p = 0,725). There were no differences between groups in the composite of adverse cardiovascular (CV) outcomes (stroke/transient ischemic attack, emergency room visit for AF, hospitalization for AF or CV death); p = 0,715. Conclusions After the index procedure, reablation occur later in RF than CB cohort.  Although the number of reconnected PV were similar between groups, right inferior PV was significantly more reconnected in pts originally treated with CB. After redo, time-to-recurrence was shorter for CB cohort. Recurrence and composite of adverse CV outcomes were similar.

scholarly journals Shorter interlesion distance is associated with a longer procedure time but not with poorer acute results of pulmonary vein isolation: results from a prospective ablation index registry

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
N Gasimova ◽  
EB Kropotkin ◽  
EA Ivanitsky ◽  
GV Kolunin ◽  
AA Nechepurenko ◽  
...  
Keyword(s):  
Multicenter Study ◽  
Pulmonary Veins ◽  
Anterior Wall ◽  
Procedure Time ◽  
Af Ablation ◽  
Ablation Index ◽  
First Pass ◽  
The Mean ◽  
Group 2 ◽  
Group 1

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): This work was supported by the Ministry of Science and Higher Education grant (Russian Federation President Grant) #MD-2314.2020.7. Background/Introduction. Radiofrequency ablation (RFA) is the mainstay of invasive management of atrial fibrillation (AF). Amongst a variety of performance indicators, interlesion distance (ILD) has a potential to become a guiding one. Uptodate clinical AF RFA protocols suggest that ILD has to be less than 6 mm, however the research is still lacking in regard to its actual targeted value. Purpose. The aim of the research is to study a relationship between ILD and first-pass isolation (FPI) in ablation-index guided AF ablation procedures. Methods. This was a prospective observational multicenter study. Data were derived from the web-based system. Pulmonary veins (PV) isolation procedures were performed according to the local practice, and RFA settings depended on operators’ preferences. A total of 446 patients were enrolled, 407 of them underwent first-time AF ablation, data on ILD available in 322 subjects (177 (55%) males, mean age 62 ± 9 years old, 259 (80%) with paroxysmal AF). A mean ILD was calculated manually in each case as a sum of all ILDs divided by number of ablation tag points. FPI was considered in cases when no additional applications were required for bidirectional PV block following creation of a one circle around ipsilateral PVs and after a 20-min waiting period. Patients were divided into two groups according to ILD (Group 1 ILD≤ 4 mm, 163 patients and Group 2 ILD > 4m, 159 patients) post-procedurally. Results.  The mean procedure time was 102 ± 52 min, the median fluoro time was 9 min [IQR 6; 15]. The following VisiTag parameters were used: the median target ablation index 400 [IQR 400; 500] on the left atrial anterior wall and 380 [IQR 380; 400] on the posterior segments, the median minimal contact force 3g [IQR 3; 4], median minimal time per a point - 4 sec [IQR 3; 15], mean catheter stability 3 mm (ranged between 2.5 and 3 mm). In 261 (81%) cases operators used 3 mm ablation tag size, and in 19% - 2 mm. The mean ILD was 4,1 ± 1,0 mm (3,2 ± 0,5 mm in Group 1 vs 4,6 ± 0,5 mm Group 2). FPI was achieved in 189 (59%) cases. In the "ILD ≤ 4 mm" group FPI was achieved in 93 (49,2%) cases and there were 96 (50,8%) cases of durable FPI in the "ILD >4 mm" group (χ2 = 2,4, p = 0,124). The mean procedure time was 111 ± 46 min and 100 ± 35 min in Group 1 and 2 (p = 0,01), respectively. The mean fluoro time was 13 ± 4 min and 11 ± 4 min in Group 1 and 2 (p = 0,08), respectively Conclusion(s). The results of our multicenter study suggest that shortening of the distance ≤4 mm has no effect on the achievement of first-pass PV isolation, but required more procedure and relatively more X-ray exposure time.

P4762What do atrial fibrillation ablation procedural volume differences across European centers reflect? An ESC EORP registry: atrial fibrillation long-term

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
E Pagourelias ◽  
V Vassilikos ◽  
C Blomstrom-Lundqvist ◽  
J Kautzner ◽  
A P Maggioni ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Clinical Epidemiology ◽  
Regional Distribution ◽  
High Volume ◽  
Af Ablation ◽  
Ablation Volume ◽  
Long Term Study ◽  
Procedural Volume ◽  
Risk Patients

Abstract Background Data from the European Atrial Fibrillation (AF) Ablation Long-Term Registry suggest that there are significant differences in the volume of AF ablation procedures performed across different centers even in the same country. If these differences in AF ablation volume between centers reflect regional, socioeconomic, infrastructural/technical or other disparities has not been addressed till now. Purpose The aim of this study was to investigate patient and non-patient related differences among European AF ablation centers according to the volume of AF ablations performed. Methods Data for this analysis originate from the European AF Ablation Long-Term Study, a prospective registry designed to describe the clinical epidemiology of patients undergoing AF ablation. Based on 25th and 75th percentiles of AF ablation numbers performed, the participating centers were classified into high volume (HV) (≥250 procedures/year), medium volume (MV) (<250 and ≥58/year) and low volume (LV) (<58/year). Patient (demographics, comorbidities) and non-patient (center infrastructure, procedural characteristics) related differences were assessed. Results A total of 91 centers in 26 European countries enrolled 3368 patients. There were no significant differences concerning regional distribution, hospital/cardiology facilities or services provided among centers with the exception of electrophysiology procedures and labs which were more abundant in HV centers (p=0.02 and <0.001 respectively). HV and MV centers ablate twice more cases of long-standing persistent and persistent AF compared to LV centers, in which paroxysmal AF reaches 78.9% of all cases (Figure A). Accordingly, first AF ablation procedure was far more frequent in LV centers compared to MV and HV (85.8% vs 76.0% vs 76.1% respectively, p<0.001). Even though HV centers ablate significantly more high risk patients (CHA2DS2-VASc score ≥2 51.4% in HV vs 46.5% in MV vs 37.2% in LV, p<0.001) (Figure B) with accompanying comorbidities, applying more elaborate ablation techniques, fluoroscopy time and radiation dose were higher among patients undergoing AF ablation in LV centers (p<0.001 for all). Despite the above-mentioned dissimilarities, Kaplan-Meier survival analysis, based on adjusted data, demonstrated non-significant differences in complication rate (p=0.402) or AF recurrence rate (p=0.363) among HV, MV and LV centers. Conclusions Volume of AF ablations in a center is not correlated with regional or infrastructural characteristics. The higher volume in HV centers consists mainly by more long-term persistent AF and higher risk patients, suggesting that differences in volume reflect differences in experience and personnel's commitment towards AF ablation.

Nonreentrant focal activations in pulmonary veins in canine model of sustained atrial fibrillation

2002 ◽  
Vol 283 (3) ◽  
pp. H1244-H1252 ◽  
Author(s):  
Shengmei Zhou ◽  
Che-Ming Chang ◽  
Tsu-Juey Wu ◽  
Yasushi Miyauchi ◽  
Yuji Okuyama ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Right Atrium ◽  
Cycle Length ◽  
Pulmonary Veins ◽  
Posterior Wall ◽  
Canine Model ◽  
Anterior Wall ◽  
High Density ◽  
The Right

Repetitive rapid activities are present in the pulmonary veins (PVs) in dogs with pacing-induced sustained atrial fibrillation (AF). The mechanisms are unclear. We induced sustained (>48 h) AF by rapidly pacing the left atrium (LA) in six dogs. High-density computerized mapping was done in the PVs and atria. Results show repetitive focal activations in all dogs and in 12 of 18 mapped PVs. Activation originated from the middle of the PV and then propagated to the LA and distal PV with conduction blocks. The right atrium (RA) was usually activated by a single large wavefront. Mean AF cycle length in the PVs (left superior, 82 ± 6 ms; left inferior, 83 ± 6 ms; right inferior, 83 ± 4 ms) and LA posterior wall (87 ± 5 ms) were significantly ( P < 0.05) shorter than those in the LA anterior wall (92 ± 4 ms) and RA (107 ± 5 ms). PVs in normal dogs did not have focal activations during induced AF. No reentrant wavefronts were demonstrated in the PVs. We conclude that nonreentrant focal activations are present in the PVs in a canine model of pacing-induced sustained AF.

scholarly journals Practical Aspects of Rotor Mapping in Catheter Ablation of Atrial Fibrillation

2017 ◽  
Vol 11 (1) ◽  
pp. 39
Author(s):  
John M Miller ◽  
Keyword(s):  
Atrial Fibrillation ◽  
Catheter Ablation ◽  
Pulmonary Veins ◽  
Accurate Diagnosis ◽  
Wide Area ◽  
Long Term Outcomes ◽  
Ablation Therapy ◽  
Af Ablation ◽  
Data Support

Historically, pulmonary veins have been the focus of atrial fibrillation (AF) ablation therapy, but it is increasingly being recognized that localized electric rotors and focal impulse sources have a role in maintaining AF. Targeting of these sources using focal impulse and rotor modulation (FIRM)-guided ablation has resulted in elimination of the source and improved long-term outcomes. FIRM uses wide-area mapping of both atria in AF, using commercially-available basket catheters (to provide contact electrograms). However, not all data support the use of FIRM. This paper provides a description of rotor mapping and ablation. In addition, practical strategies for optimizing the technique are discussed, including: catheter positioning; accurate diagnosis of the presence and locations of focal sources; and amount of ablation performed in regions with rotors or foci.

Efficacy of high-power and short-duration ablation in patients with atrial fibrillation: a prospective randomized controlled trial

EP Europace ◽  
2020 ◽  
Vol 22 (10) ◽  
pp. 1495-1501 ◽  
Author(s):  
Dong Geum Shin ◽  
Jinhee Ahn ◽  
Sang-Jin Han ◽  
Hong Euy Lim
Keyword(s):  
Atrial Fibrillation ◽  
Short Duration ◽  
High Power ◽  
Controlled Trial ◽  
Posterior Wall ◽  
Complication Rates ◽  
Related Complication ◽  
Af Ablation ◽  
Ablation Index ◽  
Significant Difference

Abstract Aims The formation of radiofrequency lesions depends on the power and duration of ablation, and the contact force (CF). Although high power (HP) creates continuous and transmural lesions, most centres still use 25–30 W for 30–40 s for safety reasons. We evaluated the clinical efficacy and safety of a HP and short-duration (HPSD) strategy for atrial fibrillation (AF) ablation. Methods and results One hundred and fifty patients [58.2 ± 10.0 years, 48% with paroxysmal AF (PAF)] scheduled for index AF ablation using a CF-sensing catheter were randomly assigned to three groups [30 W, 40 W, and 50 W at ablation sites of anterior, roof, and inferior segments of pulmonary vein (PV) antra and roof line between each upper PV]. In 25–30 W for ≤20 s was applied at posterior wall ablation site in all subjects. Compared with the 30 W and 40 W groups, procedure (P &lt; 0.001) and ablation times (P &lt; 0.001) were shorter and ablation number for PV isolation (P &lt; 0.001) was smaller in the 50 W group. There were no significant differences in the CF and ablation index (AI) among the three groups. There were no significant differences in the procedure-related complication rates. During the 12-month follow-up, AF recurred in 24 (16%) patients with no significant difference among the groups (P = 0.769). In the multivariate analysis, non-PAF [hazard ratio (HR) 2.836, P = 0.045] and AI (HR 0.983, P = 0.001) were independent risk factors for AF recurrence. Conclusion Radiofrequency ablation with HPSD is a safe and effective strategy with reduced ablation number and shortened procedure time compared to conventional ablation.

Ablation Index-guided 50W radiofrequency ablation for atrial fibrillation: lesion level analysis to ascertain determinants of safety

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
WY Ding ◽  
C Bierme ◽  
L Tovmassian ◽  
J Obrien ◽  
N Kozhuharov ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Contact Force ◽  
Regression Line ◽  
Posterior Wall ◽  
Anterior Wall ◽  
Funding Sources ◽  
Ablation Index ◽  
Lesion Level ◽  
The Mean ◽  
Level Analysis

Abstract Funding Acknowledgements Type of funding sources: None. Background The safety of Ablation Index (AI)-guided 50W ablation of atrial fibrillation (AF) remains uncertain, and the effects of this high power on other ablation parameters have not been described. We aimed to compare the safety profile of AF ablation using 50W and 35-40W. Methods 59 patients undergoing AI-guided Pulmonary Vein Isolation were enrolled including 31 with 50W and 28 with 35-40W. A contact force (CF)-sensing ablation catheter (Thermocool SmartTouch) was used to deliver point-by-point ablation according to the CLOSE protocol targeting AI values of 550-600 on the left atrial (LA) anterior wall and 400-450 on the LA posterior wall. The generator impedance graph was monitored in real-time for each lesion application. All VisiTags (n = 3766) across both groups were analysed retrospectively. Excessive ablation was defined as AI &gt;600 on the anterior wall and &gt;500 on the posterior wall. Results The mean AI was significantly higher in patients receiving 50W ablation (512 [±61] vs. 500 [±63] with 35-40W ablation, p &lt; 0.001). Excessive ablations were more frequently observed in the 50W group (10.1% vs. 5.4%, p &lt; 0.001), for both anterior and posterior wall segments (both p &lt; 0.001). There was no steam pop, and no complications in either group. Scatterplots showing the relationships between contact force (CF) and ablation time for the anterior and posterior segments of the LA for both groups are shown in the Figure. For the anterior wall, the slope of the regression line for the 50W group was -1.0 and for the 35/40W group was -0.5. Overall, there was moderate correlation between the variables CF and time in both groups (50W group: r -0.490, p &lt;0.001; 35-40W group: r -0.527, p &lt; 0.001). In the 50W group, high CF was an important predictor of excessive AI. The AUCs for anterior and posterior wall 50W ablations were 0.844 (95% CI, 0.774-0.914; p &lt; 0.001) and 0.680 (95% CI, 0.633-0.727; p &lt; 0.001), respectively. On the anterior wall, limiting the CF to 15g would reduce the number of excessive ablations to 3% and limiting CF to 10g on the posterior wall would reduce the number of excessive ablations to 9%. Conclusion Use of 50W ablation appears to be safe. but may lead to AI overshoot. Our study suggests that operators should strive to limit CF to 15g on the anterior wall and 10g on the posterior wall. Abstract Figure. Relationship between CF and abl time

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