Francesco Solimene1, Mario Giannotti Santoro2, Antonio De Simone3, Maurizio Malacrida4, Giuseppe Stabile1,5, Claudio Pandozi6, Gemma Pelargonio7,8, Filippo Maria Cauti9, Marco Scaglione10, Domenico Pecora11, Maria Grazia Bongiorni2, Alberto Arestia1, Gabriella Grimaldi3, Maurizio Russo6, Maria Lucia Narducci6, Luca Segreti2. 1. Clinica Montevergine, Mercogliano, Avellino, Italy. 2. Second Division of Cardiology, Cardiac-Thoracic-Vascular Department, New Santa Chiara Hospital, Azienda Ospedaliero Universitaria Pisana, Pisa, Italy. 3. Laboratorio di Elettrofisiologia, Clinica San Michele, Maddaloni, Caserta, Italy. 4. Boston Scientific, Milan, Italy. 5. Anthea Hospital, Bari, Italy. 6. Division of Cardiology, San Filippo Neri Hospital, Rome, Italy. 7. Department of Cardiovascular and Thoracic Sciences, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy. 8. Department of Cardiovascular and Thoracic Sciences, Catholic University of Sacred Heart, Rome, Italy. 9. Arrhythmology Unit, Ospedale San Giovanni Calibita, Fatebefratelli, Isola Tiberina, Rome, Italy. 10. Cardinal Massaia Hospital, Asti, Italy. 11. Electrophysiology Unit, Cardiovascular Department, Poliambulanza Institute Hospital Foundation, Brescia, Italy.
Abstract
BACKGROUND: Highly localized impedance (LI) measurements during AF ablation have recently emerged as a viable real-time indicator of tissue characteristics and durability of the lesions created. We report the outcomes of acute and long-term clinical evaluation of the new DirectSense™ algorithm in AF ablation. METHODS: Consecutive patients undergoing AF ablation were included in the CHARISMA registry. RF delivery was guided by the DirectSense™ algorithm, which records the magnitude and time-course of the impedance drop. The ablation endpoint was pulmonary vein isolation (PVI), as assessed by the entrance and exit block. RESULTS: 3556 point-by-point first-pass RF applications of >10sec duration were analyzed in 153 patients (mean age=59±10 years, 70% male, 61% paroxysmal AF, 39% persistent AF). The mean baseline LI was 105±15Ω prior to ablation and 92±12Ω after ablation (p<0.0001). Both absolute drops in LI and the time to LI drop (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<0.0001 for LI; 0.73[0.41-1.25]Ω/s vs 0.35[0.22-0.59]Ω/s, p<0.0001 for LI drop/τ). No major complications occurred during or after the procedures. All PVs had been successfully isolated. During a mean follow-up of 366±130 days, 18 patients (11.8%) suffered an AF/AT recurrence after the 90-day blanking period. CONCLUSION: 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. CLINICAL TRIAL REGISTRATION: Catheter Ablation of Arrhythmias with a High-Density Mapping System in Real-World Practice (CHARISMA). URL: http://clinicaltrials.gov/Identifier: NCT03793998 This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
BACKGROUND: Highly localized impedance (LI) measurements during AF ablation have recently emerged as a viable real-time indicator of tissue characteristics and durability of the lesions created. We report the outcomes of acute and long-term clinical evaluation of the new DirectSense™ algorithm in AF ablation. METHODS: Consecutive patients undergoing AF ablation were included in the CHARISMA registry. RF delivery was guided by the DirectSense™ algorithm, which records the magnitude and time-course of the impedance drop. The ablation endpoint was pulmonary vein isolation (PVI), as assessed by the entrance and exit block. RESULTS: 3556 point-by-point first-pass RF applications of >10sec duration were analyzed in 153 patients (mean age=59±10 years, 70% male, 61% paroxysmal AF, 39% persistent AF). The mean baseline LI was 105±15Ω prior to ablation and 92±12Ω after ablation (p<0.0001). Both absolute drops in LI and the time to LI drop (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<0.0001 for LI; 0.73[0.41-1.25]Ω/s vs 0.35[0.22-0.59]Ω/s, p<0.0001 for LI drop/τ). No major complications occurred during or after the procedures. All PVs had been successfully isolated. During a mean follow-up of 366±130 days, 18 patients (11.8%) suffered an AF/AT recurrence after the 90-day blanking period. CONCLUSION: 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. CLINICAL TRIAL REGISTRATION: Catheter Ablation of Arrhythmias with a High-Density Mapping System in Real-World Practice (CHARISMA). URL: http://clinicaltrials.gov/Identifier: NCT03793998 This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Entities:
Keywords:
Atrial Fibrillation; Catheter Ablation; DirectSense; Lesion Formation; Local Impedance