Ablation Index for Catheter Ablation of Atrial Fibrillation　― Clinical Applicability and Comparison With Force-Time Integral ―

Abstract Aims Despite recent advances in catheter ablation for atrial fibrillation (AF), pulmonary vein reconnection (PVR), and AF recurrence remain significantly high. Ablation index (AI) is a new method incorporating contact force, time, and power that should optimize procedural outcomes. We aimed to evaluate the efficacy and safety of AI-guided catheter ablation compared to a non-AI-guided approach. Methods and results A systematic search was performed on MEDLINE (via PubMED), EMBASE, COCHRANE, and European Society of Cardiology (ESC) databases (from inception to 1 July 2019). We included only studies that compared AI-guided with non-AI-guided catheter ablation of AF. Eleven studies reporting on 2306 patients were identified. Median follow-up period was 12 months. Ablation index-guided ablation had a significant shorter procedural time (141.0 vs. 152.8 min, P = 0.01; I2 = 90%), ablation time (21.8 vs. 32.0 min, P < 0.00001; I2 = 0%), achieved first-pass isolation more frequently [odds ratio (OR) = 0.09, 95%CI 0.04–0.21; 93.4% vs. 62.9%, P < 0.001; I2 = 58%] and was less frequently associated with acute PVR (OR = 0.37, 95%CI 0.18–0.75; 18.0% vs 35.0%; P = 0.006; I2 = 0%). Importantly, atrial arrhythmia relapse post-blanking was significantly lower in AI compared to non-AI catheter ablation (OR = 0.41, 95%CI 0.25–0.66; 11.8% vs. 24.9%, P = 0.0003; I2 = 35%). Finally, there was no difference in complication rate between AI and non-AI ablation, with the number of cardiac tamponade events in the AI group less being numerically lower (OR = 0.69, 95%CI 0.30–1.60, 1.6% vs. 2.5%, P = 0.39; I2 = 0%). Conclusions These data suggest that AI-guided catheter ablation is associated with increased efficacy of AF ablation, while preserving a comparable safety profile to non-AI catheter ablation.

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227: Contact force and force-time integral in atrial catheter ablation procedures predict bipolar electrogram criteria of transmural lesion

Archives of Cardiovascular Diseases Supplements ◽

10.1016/s1878-6480(13)71158-3 ◽

2013 ◽

Vol 5 (1) ◽

pp. 76

Author(s):

Decebal Gabriel Latcu ◽

Fabien Squara ◽

Youssef Massaad ◽

Marouane Mahjoub ◽

Nadir Saoudi

Keyword(s):

Catheter Ablation ◽

Contact Force ◽

Time Integral ◽

Atrial Catheter ◽

Force Time ◽

Force Time Integral

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Clinical utility of automated ablation lesion tagging based on catheter stability information (VisiTag Module of the CARTO 3 System) with contact force-time integral during pulmonary vein isolation for atrial fibrillation

Journal of Interventional Cardiac Electrophysiology ◽

10.1007/s10840-016-0156-z ◽

2016 ◽

Vol 47 (2) ◽

pp. 245-252 ◽

Cited By ~ 20

Author(s):

Yasuo Okumura ◽

Ichiro Watanabe ◽

Kazuki Iso ◽

Koichi Nagashima ◽

Kazumasa Sonoda ◽

...

Keyword(s):

Atrial Fibrillation ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Contact Force ◽

Clinical Utility ◽

Ablation Lesion ◽

Time Integral ◽

Force Time ◽

Catheter Stability ◽

Force Time Integral

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P1428The outcome of atrial fibrillation ablation in patients undergoing radiofrequency ablation, guided by novel indices incorporating force, time and power

EP Europace ◽

10.1093/europace/euaa162.353 ◽

2020 ◽

Vol 22 (Supplement_1) ◽

Author(s):

T Rattanakosit ◽

K Franke ◽

H Marshall ◽

T Agbaedeng ◽

P Sanders ◽

...

Keyword(s):

Atrial Fibrillation ◽

Radiofrequency Ablation ◽

Contact Force ◽

Lesion Size ◽

Fluoroscopy Time ◽

Procedure Time ◽

Time Integral ◽

Ablation Index ◽

Force Time ◽

Af Recurrence

Abstract Background Ablation index (AI) and Lesion Size Index (LSI) are novel parameters that incorporates contact force, time, and power in a weighted formula. Recent studies have shown that such indices predict lesion size and durability of pulmonary vein isolation (PVI). However, the outcomes of ablation guided by indices of force-time-power, such as PV reconnections and atrial fibrillation recurrence, have not been well characterised. Objectives To determine the association between indices of force-time-power and acute PV reconnections, procedure and fluoroscopy time and AF recurrence in patients undergoing radiofrequency PVI. Methods PUBMED and EMBASE were searched using the terms "catheter ablation" AND "Ablation index" OR "Contact force" OR "Force time integral" OR "lesion size" from inception through 22 May 2019. Studies reporting the procedure time, ablation time, fluoroscopy time, and incidence of AI acute and late reconnection and AF recurrence were included. Result Six studies were included in this study with 530 patients, which n = 416 were paroxysmal AF and 114 non-paroxysmal AF. All procedural characteristics (procedure, radiofrequency, and fluoroscopy times) were similar between AI guided and non-AI guided ablation (p > 0.05). Two studies comparing mean PV reconnections in AI guided vs. AI Blinded. Two studies compared minimum AI in reconnected vs. non-reconnected PV segments. Acute PV segment reconnection was associated with a lower minimum AI vs. non-reconnection. In 3 studies reporting AI guided vs. AI blinded ablations, AI was associated with an increased freedom from AF after average follow-up of 12 months. Conclusions Radiofrequency ablation guided by AI/LSI was associated with lower acute PV reconnection rates and improved AF freedom after PVI. There was no difference in fluoroscopy, ablation or procedure time with the use of these novel parameters. Abstract Figure.

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666Impact of local left atrial wall thickness on the incidence of acute pulmonary vein reconnection after ablation index-guided ablation

EP Europace ◽

10.1093/europace/euaa162.347 ◽

2020 ◽

Vol 22 (Supplement_1) ◽

Author(s):

M J Mulder ◽

M J B Kemme ◽

L H G A Hopman ◽

H A Hauer ◽

G J M Tahapary ◽

...

Keyword(s):

Pulmonary Vein ◽

Wall Thickness ◽

Left Atrial ◽

Atrial Wall ◽

Time Integral ◽

Left Atrial Wall ◽

Ablation Index ◽

Force Time ◽

Pulmonary Vein Reconnection ◽

Force Time Integral

Abstract Background/Introduction Pulmonary vein reconnection is considered a major determinant of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI). Ablation Index (AI)-guided ablation allows for the creation of ablation lesions of consistent depth and may reduce the incidence of pulmonary vein reconnection after PVI. However, anatomical and imaging studies have demonstrated an important inter- and intra-patient variability of left atrial wall thickness, which can result in non-transmural ablation lesion formation in thicker segments. Purpose The present study aimed to investigate the impact of local left atrial wall thickness on the incidence of acute pulmonary vein reconnection after AI-guided AF ablation. Methods Consecutive AF patients who underwent cardiac computed tomography (CT) imaging prior to AI-guided ablation between December 2017 and September 2019 were studied. AI targets were 500 for anterior/roof and 380 for posterior/inferior segments with a maximum interlesion distance of 6 mm. Occurrence of acute pulmonary vein reconnection after initial PVI was assessed after a 30-minute waiting period. Ablation procedures were analysed offline to determine minimum AI, force-time integral, contact force, ablation duration, power, impedance drop and maximum interlesion distance for each segment according to a 16-segment model. Pulmonary vein antrum wall thickness was assessed for each segment on reconstructed CT images based on patient-specific thresholds in Hounsfield Units, using a previously described method. Results Seventy patients (63% paroxysmal AF, 67% male, mean age 63 ± 8 years) who underwent preprocedural CT imaging and AI-guided AF ablation were studied. Acute reconnection (AR) occurred in 27/1152 segments (2%, 15 anterior/roof, 12 posterior/inferior) in 17/70 (24%) patients. Anterior/roof segments were thicker than posterior/inferior segments (1.48 [1.23-1.80] vs. 1.13 [1.00-1.30] mm; p < 0.01). Reconnected segments were characterised by a greater local atrial wall thickness, both in anterior/roof (1.83 [1.60-2.00] vs. 1.47 [1.20-1.80] mm; p < 0.01) and posterior/inferior (1.38 [1.25-1.50] vs. 1.13 [1.00-1.27] mm; p < 0.01) segments (Figure 1). Minimum AI, force-time integral, contact force, ablation duration, power, impedance drop and maximum interlesion distance were not associated with acute pulmonary vein reconnection. Conclusion Local atrial wall thickness is associated with acute pulmonary vein reconnection after AI-guided PVI. Individualised AI targets based on local wall thickness may be of use to create transmural ablation lesions and prevent pulmonary vein reconnection after PVI. Abstract Figure. Impact of wall thickness on reconnection

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