Lesion index: a novel guide in the path of successful pulmonary vein isolation
Previous studies indicate force time integral (FTI) as a radiofrequency (RF) lesion quality marker, while not considering power supply. Tacticath™ Quartz catheter provides Lesion index (LSI), a lesion quality marker derived by contact force (CF), power supply, and RF time combined. Our aim is to assess LSI and FTI correlation and a LSI-related cutoff of atrial fibrillation (AF) recurrences 12 months after pulmonary vein isolation (PVI).
We retrospectively enrolled 37 patients who underwent RF ablation using Tacticath™ Quartz catheter. AF recurrence rate was evaluated 3, 6, and 12 months after PVI procedure.
AF recurrence was detected in 32% of patients. FTI mean value was significantly lower in left superior pulmonary vein (LSPV: 256 ± 86 gs vs 329 ± 117 gs, p = 0.05) and right inferior pulmonary vein (RIPV: 253 ± 128 gs vs 394 ± 123 gs p = 0.006) in patients with AF recurrences; no significant differences were found in right superior pulmonary vein (RSPV) and left inferior pulmonary vein (LIPV). LSI instead was significantly higher for all veins in patients without AF recurrences: LSPV (5.2 ± 0.7 vs 4.6 ± 0.8, p = 0.03), LIPV (5.0 ± 0.8 vs 4.5 ± 0.6, p = 0.04), RSPV (5.5 ± 0.6 vs 5.1 ± 0.6, p = 0.05), and RIPV (5.5 ± 0.7 vs 4.7 ± 0.8, p = 0.006). Receiver operator characteristic curve suggests 5.3 as LSI overall cutoff value predicting freedom from disease at 1-year follow-up.
Our preliminary data suggest that a LSI mean value higher than 5.3 can be considered a good predictor of AF freedom at 1-year follow-up.
KeywordsAtrial fibrillation Catheter ablation Contact force Force time integral Lesion index Predictive lesion index
The authors acknowledge Viviana Biagioli (Scientific Secretary of the Heart Rhythm Center at Centro Cardiologico Monzino IRCCS, Milano, Italy) for editorial assistance.
Compliance with ethical standards
Conflict of interest
Elena Romanelli is employee of Abbott, Sesto San Giovanni, Italy. Salvatore Pala received consulting fees from Abbott Medical Italy. Dr. Antonio Dello Russo received consulting fees/honoraria from Biosense Webster. Dr. Gaetano Fassini, Dr. Massimo Moltrasio, and Dr. Fabrizio Tundo received consulting fees/honoraria from Medtronic. Prof. Claudio Tondo received consulting fees/honoraria from Abbott, Medtronic, Boston Scientific, and Biosense Webster. He serves as member of EU Medtronic Advisory Board and Boston Scientific Advisory Board. The other authors declare no relationships with industry.
The study was approved by the Institutional Review Board of Centro Cardiologico Monzino IRCCS.
Patients were provided informed consent.
- 7.Park CI, Lehrmann H, Keyl C, Weber R, Schiebeling J, Allgeier J, et al. Mechanisms of pulmonary vein reconnection after radiofrequency ablation of atrial fibrillation: the deterministic role of contact force and interlesion distance. J Cardiovasc Electrophysiol. 2014;25(7):701–8.CrossRefPubMedGoogle Scholar
- 17.Reddy VY, Dukkipati SR, Neuzil P, Natale A, Albenque JP, Kautzner J, et al. Randomized, controlled trial of the safety and effectiveness of a contact force-sensing irrigated catheter for ablation of paroxysmal atrial fibrillation: results of the TactiCath Contact Force Ablation Catheter Study for Atrial Fibrillation (TOCCASTAR) study. Circulation. 2015;132(10):907–15.CrossRefPubMedGoogle Scholar
- 18.De Mattia L, Crosato M, Indiani S, Causin E, Licciardello C, Squasi PAM, et al. Prospective evaluation of lesion index-guided pulmonary vein isolation technique in patients with paroxysmal atrial fibrillation: 1-year follow-up. J Atr Fibrillation. 2018;10(6):1858.CrossRefPubMedPubMedCentralGoogle Scholar
- 19.Raviele A, Disertori M, Alboni P, Bertaglia E, Botto G, Brignole M, et al. AIAC guidelines on the management and treatment of atrial fibrillation. Update 2013. Associazione Italiana di Aritmologia e Cardiostimolazione. G Ital Cardiol. 2013;14(3):215–40.Google Scholar