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Lian E, Pantlik R, Maslova V, Willert S, Moser F, Remppis A, Frank D, Demming T. Local impedance drop-guided versus lesion size index-guided pulmonary vein isolation. J Interv Card Electrophysiol 2024:10.1007/s10840-024-01870-3. [PMID: 38995604 DOI: 10.1007/s10840-024-01870-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 07/03/2024] [Indexed: 07/13/2024]
Abstract
BACKGROUND Local tissue impedance drop (LID) and lesion size index (LSI) technologies are valuable for predicting effective lesion formation. This study compares the acute and long-term efficacy of LID-guided versus LSI-guided pulmonary vein isolation (PVI) for atrial fibrillation treatment. METHODS We retrospectively analyzed two patient groups undergoing radiofrequency PVI. In the LID-guided group (n = 35), ablation was performed without contact force monitoring, stopping at the LID plateau (target LID 12 Ohm posterior, 16 Ohm anterior). In the LSI-guided group (n = 31), ablation used contact force information with target LSI (5 anterior, 4 posterior). Both groups utilized a power of 40 W anterior and 30 W posterior, with < 6 mm inter-lesion distance. Gap mapping and touch-up ablation were done if necessary. RESULTS PVI was achieved with a significantly shorter ablation time in the LSI-guided group (25 min [21;31] vs 30 [27;35], p = 0.035). PV gaps were more frequent in the LID-guided group (74% vs 42%, p = 0.016). Over 11.5 ± 2.9 months follow-up, arrhythmia recurrence was higher in the LID-guided group (34.3% vs 16.1%, p = 0.037). A redo procedure performed in 10 (28.6%) patients in the LID-guided group and 3 (9.7%) in the LSI-guided group showed chronic PV reconnections in 7 out of 10 (70%) and 2 out of 3 (67%) patients, respectively. CONCLUSIONS LSI-guided ablation results in shorter ablation time and fewer PV gaps compared to LID-guided ablation. Despite initial success, LID-guided ablation had higher arrhythmia recurrence and PV reconnections during long-term follow-up compared to LSI-guided ablation.
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Affiliation(s)
- Evgeny Lian
- Department of Internal Medicine III (Cardiology and Intensive Care Medicine), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany.
| | - Robert Pantlik
- Department of Cardiology, Heart and Vascular Center, Bad Bevensen, Germany
| | - Vera Maslova
- Department of Internal Medicine III (Cardiology and Intensive Care Medicine), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - Sven Willert
- Department of Internal Medicine III (Cardiology and Intensive Care Medicine), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - Fabian Moser
- Department of Internal Medicine III (Cardiology and Intensive Care Medicine), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - Andrew Remppis
- Department of Cardiology, Heart and Vascular Center, Bad Bevensen, Germany
| | - Derk Frank
- Department of Internal Medicine III (Cardiology and Intensive Care Medicine), University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - Thomas Demming
- Department of Cardiology, Heart and Vascular Center, Bad Bevensen, Germany
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Solimene F, Maggio R, De Sanctis V, Escande W, Malacrida M, Stabile G, Zakine C, Champ-Rigot L, Anselmino M, Ferraro A, Mantica M, Zucchelli G, Dell'Era G, Mascia G, Ricci Maga R, Pandozi C, Rossi P, Scaglione M, Zingarini G, Garnier F, Loricchio ML, Pelargonio G, Lepillier A. Contact-force local impedance algorithm to guide effective pulmonary vein isolation in AF patients: 1-year outcome from an international multicenter clinical setting. J Interv Card Electrophysiol 2024:10.1007/s10840-024-01849-0. [PMID: 38972960 DOI: 10.1007/s10840-024-01849-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 06/12/2024] [Indexed: 07/09/2024]
Abstract
BACKGROUND The combination of highly localized impedance (LI) and contact force (CF) may improve tissue characterization and lesion prediction during radiofrequency (RF) pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). OBJECTIVE We report the outcomes of our acute and long-term clinical evaluation of CF-LI-guided PVI in consecutive AF ablation cases from an international multicenter clinical setting. METHODS Three hundred twenty-four consecutive patients from 20 European centers undergoing RF catheter ablation with the Stablepoint™ catheter were enrolled in the CHARISMA registry. Of these, 275 had a minimum follow-up of 1 year and were included in the primary analysis. RESULTS The mean procedure duration was 115 ± 47 min, and the mean fluoroscopy time was 9.9 ± 6 min. At the end of the procedures, all PVs had been successfully isolated in all study patients. Minor complications were reported in 12 patients (4.4%). At 1 year, 36 (13.1%) patients had had an AF recurrence, and freedom from antiarrhythmic drugs and AF recurrence was achieved in 228 (82.9%) patients. The recurrence rate was higher in patients with persistent AF (21/116, 18.1%) than in those with paroxysmal AF (15/159, 9.4%; p = 0.0459). On multivariate logistic analysis adjusted for baseline confounders, only time > 6 months from first diagnosis of AF to ablation (HR = 2.93, 95%CI 1.03 to 8.36, p = 0.0459) was independently associated with recurrences. CONCLUSION An ablation strategy for PVI guided by CF-LI technology proved safe and effective and resulted in a low recurrence rate of AF over 1-year follow-up, irrespective of the underlying AF type. CLINICAL TRIAL REGISTRATION Catheter Ablation of Arrhythmias with a High-Density Mapping System in Real-World Practice. (CHARISMA). URL: http://clinicaltrials.gov/ Identifier: NCT03793998.
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Affiliation(s)
- Franscesco Solimene
- Department of Cardiac Electrophysiology and Arrhythmology, Clinica Montevergine, Mercogliano, Italy
- Department of Biomedical Sciences and Public Health, Marche Polytechnic University, Ancona, Italy
| | - Ruggero Maggio
- Laboratorio Di Elettrofisiologia, Infermi Hospital, 29, Rivoli, Italy.
| | | | | | | | | | | | | | - Matteo Anselmino
- Division of Cardiology, Department of Medical Sciences, "Città Della Salute E Della Scienza Di Torino" Hospital, University of Turin, Turin, Italy
| | - Anna Ferraro
- Laboratorio Di Elettrofisiologia, Infermi Hospital, 29, Rivoli, Italy
| | | | - Giulio Zucchelli
- Second Division of Cardiology, Cardiac-Thoracic-Vascular Department, New Santa Chiara Hospital, Azienda Ospedaliero Universitaria Pisana, Pisa, Italy
| | - Gabriele Dell'Era
- Azienda Ospedaliera Universitaria "Maggiore Della Carità", Novara, Italy
| | | | | | | | - Pietro Rossi
- Fatebenefratelli Isola Tiberina - Gemelli Isola Hospital, Rome, Italy
| | | | | | | | | | - Gemma Pelargonio
- Istituto Di Cardiologia Università Cattolica del Sacro Cuore, Rome, Italy
- Department of Cardiovascular Sciences, Arrhythmology Unit, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy
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Nakamura K, Sasaki T, Minami K, Aoki H, Kondo K, Yoshimura S, Kimura K, Haraguchi Y, Takizawa R, Nakatani Y, Miki Y, Goto K, Take Y, Kaseno K, Yamashita E, Naito S. Incidence, distribution, and electrogram characteristics of endocardial-epicardial connections identified by ultra-high-resolution mapping during a left atrial posterior wall isolation of atrial fibrillation. J Interv Card Electrophysiol 2024; 67:773-784. [PMID: 37843676 DOI: 10.1007/s10840-023-01663-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 10/04/2023] [Indexed: 10/17/2023]
Abstract
PURPOSE The left atrial posterior wall (LAPW) can be a target for atrial fibrillation (AF) catheter ablation but is sometimes difficult to completely isolate due to the presence of endocardial-epicardial connections. We aimed to investigate the incidence and distribution of epicardial residual connections (epi-RCs) and the electrogram characteristics at epi-RC sites during an initial LAPW isolation. METHODS We retrospectively studied 102 AF patients who underwent LAPW mapping before and after a first-pass linear ablation along the superior and inferior LAPW (pre-ablation and post-ablation maps) using an ultra-high-resolution mapping system (Rhythmia, Boston Scientific). RESULTS Epi-RCs were observed in 41 patients (40.2%) and were widely distributed in the middle LAPW area and surrounding it. The sites with epi-RCs had a higher bipolar voltage amplitude and greater number of fractionated components than those without (median, 1.09 mV vs. 0.83 mV and 3.9 vs. 3.4 on the pre-ablation map and 0.38 mV vs. 0.27 mV and 8.5 vs. 4.2 on the post-ablation map, respectively; P < 0.001). Receiver operating characteristic analyses demonstrated that the number of fractionated components on the post-ablation map had a larger area under the curve of 0.847 than the others, and the sensitivity and specificity for predicting epi-RCs were 95.4% and 62.1%, respectively, at an optimal cutoff of 5.0. CONCLUSIONS Among the patients with epi-RCs after a first-pass LAPW linear ablation, areas with a greater number of fractionated components (> 5.0 on the post-ablation LAPW map) may have endocardial-epicardial connections and may be potential targets for touch-up ablation to eliminate the epi-RCs.
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Affiliation(s)
- Kohki Nakamura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan.
| | - Takehito Sasaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Kentaro Minami
- Department of Cardiovascular Medicine, Dokkyo Medical University, 880 Kitakobayashi, Mibu-Machi, Shimotsuga-Gun, Tochigi, 321-0293, Japan
| | - Hideyuki Aoki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Kan Kondo
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Shingo Yoshimura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Kohki Kimura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Yumiko Haraguchi
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Ryoya Takizawa
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Yosuke Nakatani
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Yuko Miki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Koji Goto
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Yutaka Take
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Kenichi Kaseno
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Eiji Yamashita
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
| | - Shigeto Naito
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, 3-12 Kameizumi-Machi, Maebashi City, Gunma, 371-0004, Japan
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Bates AP, Paisey J, Yue A, Banks P, Roberts PR, Ullah W. Determinants of left atrial local impedance: Relationships with contact force, atrial fibrosis, and rhythm. J Cardiovasc Electrophysiol 2024; 35:1061-1068. [PMID: 38501564 DOI: 10.1111/jce.16253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 11/15/2023] [Accepted: 03/07/2024] [Indexed: 03/20/2024]
Abstract
INTRODUCTION The relationships between baseline tissue local impedance (LI), contact force (CF), atrial fibrosis, and atrial rhythm are uninvestigated in a clinical setting. We compared the relationship of LI and CF between atrial fibrillation (AF) and sinus rhythm (SR) accounting for the effects of atrial fibrosis as assessed by bipolar voltage and LI. METHODS Patients undergoing persistent AF ablation were recruited. LI was recorded referenced to patient blood pool (LIr) and concurrent to changes in CF, with data collected at the same locations in AF and SR. RESULTS Twenty patients were recruited. 109 locations were sampled obtaining 1903 data points (SR: 966, AF: 937). CF correlated strongly with LI (repeated measures correlation = 0.64). The relationship between CF and LIr was logarithmic. Rhythm and CF had a significant main (both p < .0005) and interaction effect (p = .022) on tissue LI: AF demonstrated higher LIr values than SR for similar CF. Bipolar voltage had no effect on the relationship of CF to LIr in either rhythm. Assessing fibrosis using LIr showed an interaction effect with CF for LIr in SR and AF, (SR: p < .0005, AF: p = .01), with increased fibrosis showing lesser change in LIr per gram of CF. CONCLUSIONS CF and rhythm significantly affect the measured LIr of LA myocardium. Optimal catheter-tissue coupling may be better achieved with higher levels of CF and in AF rather than SR. Atrial fibrosis, as assessed by LIr but not bipolar voltage, affected the CF-LI relationship.
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Affiliation(s)
- Alexander P Bates
- Department of Cardiology, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, UK
- School of Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK
| | - John Paisey
- Department of Cardiology, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, UK
| | - Arthur Yue
- Department of Cardiology, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, UK
| | - Phil Banks
- Department of Cardiology, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, UK
| | - Paul R Roberts
- Department of Cardiology, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, UK
- School of Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Waqas Ullah
- Department of Cardiology, University Hospital Southampton NHS Foundation Trust, Tremona Road, Southampton, UK
- School of Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK
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Nagase T, Kikuchi T, Unno T, Arai R, Tatsukawa S, Yoshida Y, Yoshino C, Nishida T, Tanaka T, Ishino M, Kato R, Kuwada M. Impedance-guided modified CLOSE protocol ablation can reduce ablation index necessary for pulmonary vein isolation in patients with atrial fibrillation. J Cardiol 2024; 83:291-297. [PMID: 37684006 DOI: 10.1016/j.jjcc.2023.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 07/21/2023] [Accepted: 09/01/2023] [Indexed: 09/10/2023]
Abstract
BACKGROUND Real-time monitoring of generator impedance drop is not considered in CLOSE protocol pulmonary vein (PV) isolation (PVI) in patients with atrial fibrillation (AF). We verified whether additional information of impedance drop could minimize ablation index required for PVI using modified CLOSE protocol (target ablation index ≥ 500 on anterior wall and ≥400 on posterior wall along with inter-lesion distance of 3-6 mm and maximum power of 35 W) without any adverse effect of procedural data and efficacy. METHODS Sixty consecutive Japanese AF patients [paroxysmal AF: 43 (72 %) patients] underwent first-time PVI with modified CLOSE protocol with real-time monitoring of impedance drop (impedance-guided modified CLOSE protocol). Ablation tags were colored according to impedance drop and ablation was immediately terminated before reaching target ablation index if impedance drop of ≥10 Ω was confirmed. Ablation index needed for PVI, first-pass PVI rate, other procedural data, and atrial tachyarrhythmia recurrence were evaluated. RESULTS Mean ablation index and impedance drop on anterior and posterior walls were 437.6 ± 43.5 Ω and 10.2 ± 2.6 Ω and 393.3 ± 27.4 Ω and 9.3 ± 2.2 Ω, respectively. First-pass PVI per PV pair was accomplished in 90/120 (75 %). No complications occurred. PV gaps after first-pass ablation were locationally most often found on right posterior wall than on the other parts (p < 0.001). There were no differences in mean contact force, impedance drop, and ablation index between walls with and without PV gaps after first-pass PV ablation. During a mean follow-up of 24 ± 9 months, survival from atrial tachyarrhythmia recurrence was 51/60 (85 %) patients. CONCLUSIONS Using additional generator impedance drop information may be useful to minimize radiofrequency current application to accomplish PVI with modified CLOSE protocol while maintaining efficacy and safety in Japanese AF population.
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Affiliation(s)
- Takahiko Nagase
- Department of Cardiology, Higashiyamato Hospital, Tokyo, Japan.
| | | | - Takatoshi Unno
- Department of Cardiology, Higashiyamato Hospital, Tokyo, Japan
| | - Ryoichi Arai
- Department of Cardiology, Higashiyamato Hospital, Tokyo, Japan
| | | | | | - Chiyo Yoshino
- Department of Cardiology, Higashiyamato Hospital, Tokyo, Japan
| | | | - Takahisa Tanaka
- Department of Cardiology, Higashiyamato Hospital, Tokyo, Japan
| | | | - Ryuichi Kato
- Department of Cardiology, Higashiyamato Hospital, Tokyo, Japan
| | - Masao Kuwada
- Department of Cardiology, Higashiyamato Hospital, Tokyo, Japan
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Nomura T, Maeda M, Kumazawa D, Mizuno Y, Onodera K, Toyoda S, Yamashita K. The effect of ablation settings on lesion characteristics with DiamondTemp ablation system: An ex vivo experiment. J Arrhythm 2024; 40:109-117. [PMID: 38333399 PMCID: PMC10848608 DOI: 10.1002/joa3.12970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 11/06/2023] [Accepted: 11/20/2023] [Indexed: 02/10/2024] Open
Abstract
Introduction Creating large lesion in ablations using the DiamondTemp (DTA) ablation system may reduce the frequency of arrhythmia recurrence and allow the treatment of ventricular arrhythmias. Therefore, this study aimed to investigate whether power, application time, contact force (CF), and contact angle affect lesion formation in the ventricles. Methods Ablations were delivered to porcine myocardial preps to evaluate the lesion characteristics. Ablations were conducted with a maximum power of 50 W, target temperature of 58°C, CF of 10, 20, or 30 g, and contact angle between the catheter tip and tissue. The ablation durations were 15, 30, 60 s, 15 s × 2, or 30 s × 2. Results Steam pops occurred only in cases with perpendicular contact. The lesion depth was larger in all settings in the perpendicular orientation than in the parallel orientation. The temperatures were lower in all settings in the perpendicular orientation than in the parallel orientation. The lesions became larger as CF increased with perpendicular contact and duration of ≥30 s. The longer application time resulted in larger surface area, depth, and volume of the lesion. Lesion depth was greater with single application of 30 and 60 s than with 15 s × 2 and 30 s × 2, respectively. Conclusion It is important to perform a single prolonged application as much as possible to create deeper lesions. Parallel contact with the tissue should be maintained to take advantage of the temperature sensor's capabilities to avoid pop phenomenon.
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Affiliation(s)
- Takehiro Nomura
- Heart Rhythm Center, Department of Cardiovascular MedicineSendai Kosei HospitalSendai‐shiMiyagiJapan
| | - Manabu Maeda
- Heart Rhythm Center, Department of Cardiovascular MedicineSendai Kosei HospitalSendai‐shiMiyagiJapan
| | - Daiki Kumazawa
- Heart Rhythm Center, Department of Cardiovascular MedicineSendai Kosei HospitalSendai‐shiMiyagiJapan
| | - Yosuke Mizuno
- Heart Rhythm Center, Department of Cardiovascular MedicineSendai Kosei HospitalSendai‐shiMiyagiJapan
| | - Kosuke Onodera
- Heart Rhythm Center, Department of Cardiovascular MedicineSendai Kosei HospitalSendai‐shiMiyagiJapan
| | - Shigeru Toyoda
- Department of Cardiovascular Medicine, School of MedicineDokkyo Medical UniversityMibuTochigiJapan
| | - Kennosuke Yamashita
- Heart Rhythm Center, Department of Cardiovascular MedicineSendai Kosei HospitalSendai‐shiMiyagiJapan
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Yamashita S, Mizukami A, Ono M, Hiroki J, Miyakuni S, Ueshima D, Matsumura A, Miyazaki S, Sasano T. Higher power achieves greater local impedance drop, shorter ablation time, and more transmural lesion formation in comparison to lower power in local impedance guided radiofrequency ablation of atrial fibrillation. J Cardiovasc Electrophysiol 2023; 34:1869-1877. [PMID: 37529869 DOI: 10.1111/jce.16025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/17/2023] [Accepted: 07/22/2023] [Indexed: 08/03/2023]
Abstract
BACKGROUND Since the local impedance (LI) of the ablation catheter reflects tissue characteristics, the efficacy of higher power (HP) compared to lower power (LP) in LI-guided ablation may differ from other index-guided ablations. OBJECTIVE This study aimed to assess the efficacy of HP ablation in LI-guided ablation of atrial fibrillation (AF). METHODS A prospective observational study was conducted, enrolling patients undergoing de novo ablation for AF. Pulmonary vein isolation was performed using point-by-point ablation with a RHYTHMIA HDxTM Mapping System and an open-irrigated ablation catheter with mini-electrodes (IntellaNav MIFI OI). Ablation was stopped when the LI drop reached 30 ohms, three seconds after the LI plateaued, or when ablation time reached 30 s. To balance the baseline differences, a unique method was used in which the power was changed between HP (45 W to anterior wall/40 W to posterior wall) and LP (35 W/30 W) alternately for each adjacent point. RESULTS A total of 551 ablations in 10 patients were analyzed (HP, n = 276; LP, n = 275). The maximum LI drop was significantly larger (HP: 28.3 ± 5.4 vs. LP: 24.8 ± 6.3 ohm), and the time to minimum LI was significantly shorter (HP: 15.0 ± 6.3 vs. LP: 19.3 ± 6.6 s) in the HP setting. The unipolar electrogram analysis of three patients revealed that the electrogram indicating transmural lesion formation was observed more frequently in the HP setting. CONCLUSION In LI-guided ablation, the HP could achieve a larger LI drop and shorter time to minimum LI, which may result in more transmural lesion formation compared to a LP setting.
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Affiliation(s)
- Shu Yamashita
- Department of Cardiology, National Hospital Organization Disaster Medical Center, Tokyo, Japan
| | - Akira Mizukami
- Department of Cardiology, Kameda Medical Center, Chiba, Japan
| | - Maki Ono
- Department of Cardiology, Kameda Medical Center, Chiba, Japan
| | - Jiro Hiroki
- Department of Cardiology, Kameda Medical Center, Chiba, Japan
| | - Shota Miyakuni
- Department of Cardiology, Kameda Medical Center, Chiba, Japan
| | - Daisuke Ueshima
- Department of Cardiology, Kameda Medical Center, Chiba, Japan
| | | | - Shinsuke Miyazaki
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tetsuo Sasano
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, Japan
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Takigawa M, Yamamoto T, Amemiya M, Martin CA, Ikenouchi T, Yamaguchi J, Negishi M, Goto K, Shigeta T, Nishimura T, Tao S, Miyazaki S, Goya M, Sasano T. Impact of baseline pool impedance on lesion metrics and steam pops in catheter ablation. J Cardiovasc Electrophysiol 2023; 34:1671-1680. [PMID: 37337433 DOI: 10.1111/jce.15964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/19/2023] [Accepted: 05/29/2023] [Indexed: 06/21/2023]
Abstract
INTRODUCTION Little is known about the impact of blood-pool local impedance (LI) on lesion characteristics and the incidence of steam pops. METHODS Radiofrequency applications at a range of powers (30, 40, and 50 W), contact forces (CF) (5, 15, and 25 g), and durations (15, 30, 45, and 120 s) using perpendicular/parallel catheter orientation were performed in 40 excised porcine preparations, using a catheter capable of monitoring LI (StablePoint©, Boston Scientific). To simulate the variability in blood-pool impedance, the saline-pool LI was modulated by calibrating saline concentrations. Lesion characteristics were compared under three values of saline-pool LI: 120, 160, and 200 Ω. RESULTS Of 648 lesions created, steam pops occurred in 175 (27.0%). When power, CF, time, and catheter orientation were adjusted, ablation at a saline-pool impedance of 160 or 200 Ω more than doubled the risk of steam pops compared with a saline-pool impedance of 120 Ω (Odds ratio = 2.31; p = .0002). Lesions in a saline-pool impedance of 120 Ω were significantly larger in surface area (50 [38-62], 45 [34-56], and 41 [34-60] mm2 for 120, 160, and 200 Ω, p < .05), but shallower in depth (4.0 [3-5], 4.4 [3.2-5.3], and 4.5 [3.8-5.5] mmfor 120, 160, and 200 Ω, respectively, p < .05) compared with the other two settings. The correlation between the absolute LI-drop and lesion size weakened as the saline-pool LI became higher (e.g., 120 Ω group (r2 = .30, r2 = .18, and r2 = .16, respectively for 120, 160, and 200 Ω), but the usage of %LI-drop (= absolute LI-drop/initial LI) instead of absolute LI-drop may minimize this effect. CONCLUSIONS In an experimental model, baseline saline-pool impedance significantly affects the lesion metrics and the risk of steam pops.
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Affiliation(s)
- Masateru Takigawa
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tasuku Yamamoto
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Miki Amemiya
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Claire A Martin
- Royal Papworth Hospital, Cambridge University, Cambridge, UK
| | - Takashi Ikenouchi
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Junji Yamaguchi
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Miho Negishi
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kentaro Goto
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takatoshi Shigeta
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takuro Nishimura
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Susumu Tao
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shinsuke Miyazaki
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masahiko Goya
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tetsuo Sasano
- Department of Cardiovascular Medicine, Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan
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Lepillier A, Maggio R, De Sanctis V, Malacrida M, Stabile G, Zakine C, Champ-Rigot L, Anselmino M, Segreti L, Dell’Era G, Garnier F, Mascia G, Pandozi C, Dello Russo A, Scaglione M, Cosaro G, Ferraro A, Paziaud O, Maglia G, Solimene F. Insight into contact force local impedance technology for predicting effective pulmonary vein isolation. Front Cardiovasc Med 2023; 10:1169037. [PMID: 37476572 PMCID: PMC10354239 DOI: 10.3389/fcvm.2023.1169037] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 06/19/2023] [Indexed: 07/22/2023] Open
Abstract
Background Highly localized impedance (LI) measurements during atrial fibrillation (AF) ablation have the potential to act as a reliable predictor of the durability of the lesions created. Objective We aimed to collect data on the procedural parameters affecting LI-guided ablation in a large multicenter registry. Methods A total of 212 consecutive patients enrolled in the CHARISMA registry and undergoing their first pulmonary vein (PV) isolation for paroxysmal and persistent AF were included. Results In all, 13,891 radiofrequency (RF) applications of ≥3 s duration were assessed. The first-pass PV isolation rate was 93.3%. A total of 80 PV gaps were detected. At successful ablation spots, baseline LI and absolute LI drop were larger than at PV gap spots (161.4 ± 19 Ω vs. 153.0 ± 13 Ω, p < 0.0001 for baseline LI; 22.1 ± 9 Ω vs. 14.4 ± 5 Ω, p < 0.0001 for LI drop). On the basis of Receiver operating characteristic curve analysis, the ideal LI drop, which predicted successful ablation, was >21 Ω at anterior sites and >18 Ω at posterior sites. There was a non-linear association between the magnitude of LI drop and contact-force (CF) (r = 0.14, 95% CI: 0.13-0.16, p < 0.0001) whereas both CF and LI drop were inversely related with delivery time (DT) (-0.22, -0.23 to -0.20, p < 0.0001 for CF; -0.27, -0.29 to -0.26, p < 0.0001 for LI drop). Conclusion An LI drop >21 Ω at anterior sites and >18 Ω at posterior sites predicts successful ablation. A higher CF was associated with an increased likelihood of ideal LI drop. The combination of good CF and adequate LI drop allows a significant reduction in RF DT. Clinical trial registration http://clinicaltrials.gov/, identifier: NCT03793998.
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Affiliation(s)
| | | | | | | | | | | | | | - Matteo Anselmino
- Division of Cardiology, “Città della Salute e della Scienza di Torino” Hospital, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Luca Segreti
- Second Division of Cardiology, Cardiac-Thoracic-Vascular Department, New Santa Chiara Hospital, Azienda Ospedaliero Universitaria Pisana, Pisa, Italy
| | - Gabriele Dell’Era
- Azienda Ospedaliera Universitaria “Maggiore della Carità”, Novara, Italy
| | | | | | | | - Antonio Dello Russo
- Cardiology and Arrhythmology Clinic, Marche Polytechnic University, Ancona, Italy
| | | | | | | | | | | | - Francesco Solimene
- Department of Cardiac Electrophysiology and Arrhythmology, Clinica Montevergine, Mercogliano, Italy
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10
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Di C, Wang Q, Wu Y, Li L, Lin W. Monitoring Spike Potential and Abrupt Impedance Rise with Concomitant Temperature/Contact Force Change for Timely Detection of the Occurrence of “Silent” or “Nonaudible” Steam Pop. J Interv Cardiol 2023; 2023:8873404. [PMID: 37064642 PMCID: PMC10098411 DOI: 10.1155/2023/8873404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 03/14/2023] [Accepted: 03/28/2023] [Indexed: 04/08/2023] Open
Abstract
Aim. Steam pop (SP) during radiofrequency catheter ablation (RFCA) for pulmonary vein isolation (PVI) may cause cardiac perforation, which may require drainage and emergent thoracotomy or even lead to death. Data investigating the timely detection of the occurrence of “silent” or “nonaudible” SP events are limited. Methods and Results. A total of 516 consecutive atrial fibrillation (AF) patients who underwent index PVI were included in this retrospective observational study. The duration, power, impedance, temperature, and contact force (CF) of RFCA were continually monitored and recorded throughout the procedure. A total of 15 (2.9%) audible SP events occurred in 14 patients; 2 of the patients developed pericardial tamponade, 1 patient underwent drainage, and 1 patient underwent emergent thoracotomy. The time from RFCA initiation to the occurrence of audible SP was 19.4 ± 6.9 s. Abrupt temperature change occurred in 13 (86.7%) of the 15 SP events, of which 8 (53.3%) exhibited an abrupt temperature rise of 2.3 ± 1.0°C, 5 (33.3%) exhibited an abrupt temperature drop of 2.3 ± 1.3°C, and 2 (13.3%) exhibited no discernible temperature change. Conclusions. In conclusion, simultaneously recorded spike potentials and abrupt impedance rise with concomitant temperature and/or CF change could be a feasible method for the timely detection of the occurrence of audible, “silent,” or “nonaudible” SP events, particularly in regions where the risk of perforation may be of concern.
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Affiliation(s)
- Chengye Di
- Cardiac Electrophysiology Unit, First Department of Cardiology, TEDA International Cardiovascular Hospital, Tianjin, China
- College of Clinical Cardiology, Tianjin Medical University, Tianjin, China
- Cardiovascular Institute, Tianjin University, Tianjin, China
| | - Qun Wang
- Cardiac Electrophysiology Unit, First Department of Cardiology, TEDA International Cardiovascular Hospital, Tianjin, China
- College of Clinical Cardiology, Tianjin Medical University, Tianjin, China
- Cardiovascular Institute, Tianjin University, Tianjin, China
| | - Yanxi Wu
- Cardiac Electrophysiology Unit, First Department of Cardiology, TEDA International Cardiovascular Hospital, Tianjin, China
- College of Clinical Cardiology, Tianjin Medical University, Tianjin, China
- Cardiovascular Institute, Tianjin University, Tianjin, China
| | - Longyu Li
- Cardiac Electrophysiology Unit, First Department of Cardiology, TEDA International Cardiovascular Hospital, Tianjin, China
- College of Clinical Cardiology, Tianjin Medical University, Tianjin, China
- Cardiovascular Institute, Tianjin University, Tianjin, China
| | - Wenhua Lin
- Cardiac Electrophysiology Unit, First Department of Cardiology, TEDA International Cardiovascular Hospital, Tianjin, China
- College of Clinical Cardiology, Tianjin Medical University, Tianjin, China
- Cardiovascular Institute, Tianjin University, Tianjin, China
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11
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Kawakami S, Ogawa E, Fukaya H, Matsuura G, Aiga S, Kumagai H. Estimation of mechanical properties by transcatheter monitoring using local impedance and contact force. J Med Eng Technol 2023; 47:141-146. [PMID: 36426804 DOI: 10.1080/03091902.2022.2134479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The mechanical properties of the myocardium in the left ventricle and right atrium were estimated by simultaneously measuring the local impedance (LI) and contact force (CF) using an ablation catheter. Radiofrequency catheter ablation (RFCA) is a well-established arrhythmia treatment. Monitoring the RF power, CF and properties of myocardium during RFCA are necessary to estimate the effect of ablation. Indices, such as CF, lesion size index and ablation index, do not include the myocardium mechanical properties. Therefore, there is the risk of side effects, such as cardiac tamponade, by excessive catheter indentation into vulnerable areas. We propose the simultaneous measurement of LI and CF for estimating the myocardial mechanical properties to reduce the side effects. In this study, an in vitro experimental system was constructed to measure LI and CF via the catheter. The relationship between the porcine myocardial tissue thickness and CF-LI curve was investigated using the left ventricle and right atrium. Power function coefficients approximating the CF-LI curve increased with thicker left ventricle. The thickness of the myocardium can be estimated by simultaneously measuring LI and CF. Intraoperative measurement of the myocardial mechanical properties can be used to determine the ablation conditions at each site.
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Affiliation(s)
- Sota Kawakami
- Graduate School of Medical Sciences, Kitasato University, Kanagawa, Japan
| | - Emiyu Ogawa
- Graduate School of Medical Sciences, Kitasato University, Kanagawa, Japan.,Allied Health Sciences, Kitasato University, Kanagawa, Japan
| | - Hidehira Fukaya
- Department of Cardiovascular Medicine, Kitasato University Hospital, Kanagawa, Japan
| | - Gen Matsuura
- Department of Cardiovascular Medicine, Kitasato University Hospital, Kanagawa, Japan
| | - Sumire Aiga
- Allied Health Sciences, Kitasato University, Kanagawa, Japan
| | - Hiroshi Kumagai
- Graduate School of Medical Sciences, Kitasato University, Kanagawa, Japan.,Allied Health Sciences, Kitasato University, Kanagawa, Japan
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12
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Fukaya H, Mori H, Oikawa J, Kawano D, Nakamura H, Ishizue N, Kishihara J, Hojo R, Tsutsui K, Ikeda Y, Kato R, Fukamizu S. Optimal local impedance parameters for successful pulmonary vein isolation in patients with atrial fibrillation. J Cardiovasc Electrophysiol 2023; 34:71-81. [PMID: 36378816 DOI: 10.1111/jce.15748] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/24/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022]
Abstract
INTRODUCTION Local impedance (LI) parameters of IntellaNav STABLEPOINT for successful pulmonary vein isolation (PVI) of atrial fibrillation (AF) remain unclear. The purpose of this study was to seek LI data achieving successful PVI. METHODS Consecutive AF patients who underwent catheter ablation with STABLEPOINT were prospectively enrolled in two centers. PVI was performed under a constant 35-or 40-watt power, 20-s duration, and >5-g contact force. The operators were blinded to the LI data. The characteristics of all ablation points with/without conduction gaps (Unsuccess or Success tags) after the first-attempt PVI were evaluated for the right/left PVs and anterior/posterior wall (RPV/LPV and AW/PW, respectively), and cutoff values of LI data were calculated for successful lesion formation. RESULTS A total of 5257 ablation points in 102 patients (65 [58-72] years old, 65.7% male) were evaluated. The LI drop values were higher in the Success tags than Unsuccess tags on the LPV-AW and RPV-AW/PW (p < .001), except for the LPV-PW (p = .105). The %LI drop values (LI drop/initial LI) were higher for the Success tags in all areas (15.8 [12.2%-19.6%] vs. 11.6 [9.7%-15.6%] in LPV-AW: p < .001, 15.0 [11.5%-19.3%] vs. 11.4 [8.7%-17.3%] in LPV-PW: p = .035, 15.3 [11.5%-19.4%] vs. 9.9 [8.1%-13.7%] in RPV-AW: p < .001, and 13.3 [10.1%-17.4%] vs. 8.1 [6.3%-9.5%] in RPV-PW, p < .001). The LI drop and %LI drop cutoff values were 20.0 ohms and 11.6%, respectively. CONCLUSIONS An insufficient LI drop with STABLEPOINT was associated with a gap formation during PVI, and the best cutoff values for the LI drop and %LI drop were 20.0 ohms and 11.6%, respectively.
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Affiliation(s)
- Hidehira Fukaya
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Hitoshi Mori
- Department of Cardiovascular Medicine, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Jun Oikawa
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Daisuke Kawano
- Department of Cardiovascular Medicine, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Hironori Nakamura
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Naruya Ishizue
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Jun Kishihara
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Rintaro Hojo
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
| | - Kenta Tsutsui
- Department of Cardiovascular Medicine, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Yoshifumi Ikeda
- Department of Cardiovascular Medicine, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Ritsushi Kato
- Department of Cardiovascular Medicine, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Seiji Fukamizu
- Department of Cardiology, Tokyo Metropolitan Hiroo Hospital, Tokyo, Japan
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13
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Biophysical Tissue Characterization of Ventricular Tachycardia Substrate With Local Impedance Mapping to Predict Critical Sites. JACC Clin Electrophysiol 2022:S2405-500X(22)01055-6. [PMID: 36752472 DOI: 10.1016/j.jacep.2022.11.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 11/08/2022] [Accepted: 11/20/2022] [Indexed: 01/20/2023]
Abstract
BACKGROUND New tools are needed to improve ventricular tachycardia (VT) substrate characterization and optimize outcomes. LI provides biophysical tissue characterization. OBJECTIVES The purpose of this study was to test local impedance (LI)-based mapping to predict critical ventricular tachycardia components after myocardial infarction (MI). METHODS One month after a nonreperfused anterior MI, endo-epicardial high-density electroanatomic mapping and endocardial LI mapping were performed in 23 Landrace Large X White pigs. LI thresholds were set using the blood pool value to define a 10 Ω range: low (<blood pool -1Ω), intermediate (≥blood pool -1Ω and ≤blood pool +9Ω), and high (normal) tissue resistance (>blood pool +9Ω). RESULTS Low LI was detected in low-voltage areas in 100% of cases, but intermediate LI was found in both core (87%) and border zone (12.5%) voltage areas. A total of 17 VTs were induced (VT isthmus identified in 9 animals). VT inducibility was associated with the size of intermediate LI area (OR: 1.19 [95% CI: 1.0-1.4]; P = 0.039) and the presence of specific LI patterns: LI corridor (OR: 15.0 [95% CI: 1.3-169.9]; P = 0.029); LI gradient (OR: 30.0 [95% CI: 2.1-421.1]; P = 0.012), high LI heterogeneity (OR: 21.7 [95% CI: 1.8-260.6]; P = 0.015), and presence of ≥2 low LI regions (OR: 11.3 [95% CI: 1.0-130.2]; P = 0.053). Potential VT isthmuses were in areas of intermediate LI and colocalized to LI patterns associated with VT inducibility in all cases (LI corridors or LI gradient). Low LI regions did not actively participate in the VT circuit (0%). CONCLUSIONS LI mapping is feasible and may add useful characterization of the VT substrate. Specific LI patterns (ie, corridors, gradients) were associated with VT inducibility and colocalized with the VT isthmus, thus representing a potential new target for ablation in substrate-based procedures.
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14
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Alken FA, Scherschel K, Kahle AK, Masjedi M, Meyer C. Combined contact force and local impedance dynamics during repeat atrial fibrillation catheter ablation. Front Physiol 2022; 13:1001719. [PMID: 36311229 PMCID: PMC9606811 DOI: 10.3389/fphys.2022.1001719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 09/21/2022] [Indexed: 11/30/2022] Open
Abstract
Background: Optimal lesion formation during catheter-based radiofrequency current (RFC) ablation depends on electro-mechanical tip-tissue coupling measurable via contact force (CF) and local impedance (LI) monitoring. We aimed to investigate CF and LI dynamics in patients with previous atrial fibrillation (AF) ablation who frequently present with heterogenous arrhythmia substrate. Methods: Data from consecutive patients presenting for repeat AF or atrial tachycardia ablation using a novel open-irrigated single-tip ablation catheter were studied. RFC applications were investigated regarding CF, LI and the maximum LI drop (∆LI) for evaluation of ablation efficacy. ∆LI > 20 Ω was defined as a successful RFC application. Results: A total of 730 RFC applications in 20 patients were analyzed. Baseline CF was not associated with baseline LI (R = 0.06, p = 0.17). A mean CF < 8 g during ablation resulted in lower ∆LI (<8 g: 13 Ω vs. ≥ 8 g: 16 Ω, p < 0.001). Baseline LI showed a better correlation with ∆LI (R = 0.35, p < 0.001) compared to mean CF (R = 0.17, p < 0.001). Mean CF correlated better with ∆LI in regions of low (R = 0.31, p < 0.001) compared to high (R = 0.21, p = 0.02) and intermediate voltage (R = 0.17, p = 0.004). Combined CF and baseline LI predicted ∆LI > 20 Ω (area under the receiver operating characteristic curve (AUC) 0.75) better compared to baseline LI (AUC 0.72), mean CF (AUC 0.60), force-time integral (AUC 0.59) and local bipolar voltage (0.55). Conclusion: Combination of CF and LI may aid monitoring real-time catheter-tissue electro-mechanical coupling and lesion formation within heterogenous atrial arrhythmia substrate in patients with repeat AF or atrial tachycardia ablation.
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Affiliation(s)
- Fares-Alexander Alken
- Division of Cardiology, Angiology and Intensive Care, cNEP, Cardiac Neuro- and Electrophysiology Research Group, EVK Düsseldorf, Düsseldorf, Germany
| | - Katharina Scherschel
- Division of Cardiology, Angiology and Intensive Care, cNEP, Cardiac Neuro- and Electrophysiology Research Group, EVK Düsseldorf, Düsseldorf, Germany
- Department of Neurophysiology, Heinrich-Heine-University Düsseldorf, Medical Faculty, cNEP, Cardiac Neuro- and Electrophysiology Research Consortium, Düsseldorf, Germany
| | - Ann-Kathrin Kahle
- Division of Cardiology, Angiology and Intensive Care, cNEP, Cardiac Neuro- and Electrophysiology Research Group, EVK Düsseldorf, Düsseldorf, Germany
- Department of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Mustafa Masjedi
- Division of Cardiology, Angiology and Intensive Care, cNEP, Cardiac Neuro- and Electrophysiology Research Group, EVK Düsseldorf, Düsseldorf, Germany
- Department of Neurophysiology, Heinrich-Heine-University Düsseldorf, Medical Faculty, cNEP, Cardiac Neuro- and Electrophysiology Research Consortium, Düsseldorf, Germany
| | - Christian Meyer
- Division of Cardiology, Angiology and Intensive Care, cNEP, Cardiac Neuro- and Electrophysiology Research Group, EVK Düsseldorf, Düsseldorf, Germany
- Department of Neurophysiology, Heinrich-Heine-University Düsseldorf, Medical Faculty, cNEP, Cardiac Neuro- and Electrophysiology Research Consortium, Düsseldorf, Germany
- *Correspondence: Christian Meyer,
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15
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Limitations of Baseline Impedance, Impedance Drop and Current for Radiofrequency Catheter Ablation Monitoring: Insights from In silico Modeling. J Cardiovasc Dev Dis 2022; 9:jcdd9100336. [PMID: 36286288 PMCID: PMC9604830 DOI: 10.3390/jcdd9100336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/26/2022] [Accepted: 09/28/2022] [Indexed: 11/06/2022] Open
Abstract
Background: Baseline impedance, radiofrequency current, and impedance drop during radiofrequency catheter ablation are thought to predict effective lesion formation. However, quantifying the contributions of local versus remote impedances provides insights into the limitations of indices using those parameters. Methods: An in silico model of left atrial radiofrequency catheter ablation was used based on human thoracic measurements and solved for (1) initial impedance (Z), (2) percentage of radiofrequency power delivered to the myocardium and blood (3) total radiofrequency current, (4) impedance drop during heating, and (5) lesion size after a 25 W−30 s ablation. Remote impedance was modeled by varying the mixing ratio between skeletal muscle and fat. Local impedance was modeled by varying insertion depth of the electrode (ID). Results: Increasing the remote impedance led to increased baseline impedance, lower system current delivery, and reduced lesion size. For ID = 0.5 mm, Z ranged from 115 to 132 Ω when fat percentage varied from 20 to 80%, resulting in a decrease in the RF current from 472 to 347 mA and a slight decrease in lesion size from 5.6 to 5.1 mm in depth, and from 9.2 to 8.0 mm in maximum width. In contrast, increasing the local impedance led to lower system current but larger lesions. For a 50% fat−muscle mixture, Z ranged from 118 to 138 Ω when ID varied from 0.3 to 1.9 mm, resulting in a decrease in the RF current from 463 to 443 mA and an increase in lesion size, from 5.2 up to 7.5 mm in depth, and from 8.4 up to 11.6 mm in maximum width. In cases of nearly identical Z but different contributions of local and remote impedance, markedly different lesions sizes were observed despite only small differences in RF current. Impedance drop better predicted lesion size (R2 > 0.93) than RF current (R2 < 0.1). Conclusions: Identical baseline impedances and observed RF currents can lead to markedly different lesion sizes with different relative contributions of local and remote impedances to the electrical circuit. These results provide mechanistic insights into the advantage of measuring local impedance and identifies potential limitations of indices incorporating baseline impedance or current to predict lesion quality.
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16
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Xu L, Khoshknab M, Berger RD, Chrispin J, Dixit S, Santangeli P, Callans D, Marchlinski FE, Zimmerman SL, Han Y, Trayanova N, Desjardins B, Nazarian S. Lipomatous Metaplasia Enables Ventricular Tachycardia by Reducing Current Loss Within the Protected Corridor. JACC Clin Electrophysiol 2022; 8:1274-1285. [PMID: 36266004 PMCID: PMC11148646 DOI: 10.1016/j.jacep.2022.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 06/23/2022] [Accepted: 07/01/2022] [Indexed: 11/19/2022]
Abstract
BACKGROUND Post-myocardial infarction ventricular tachycardia (VT) is due to re-entry through surviving conductive myocardial corridors across infarcted tissue. However, not all conductive corridors participate in re-entry. OBJECTIVES This study sought to test the hypothesis that critical VT corridors are more likely to traverse near lipomatous metaplasia (LM) and that current loss is reduced during impulse propagation through such corridors. METHODS Among 30 patients in the Prospective 2-center INFINITY (Intra-Myocardial Fat Deposition and Ventricular Tachycardia in Cardiomyopathy) study, potential VT-viable corridors within myocardial scar or LM were computed from late gadolinium enhancement cardiac magnetic resonance images. Because late gadolinium enhancement highlights both scar and LM, LM was distinguished from scar by using computed tomography. The SD of the current along each corridor was measured. RESULTS Scar exhibited lower impedance than LM (median Z-score -0.22 [IQR: -0.84 to 0.35] vs -0.07 [IQR: -0.67 to 0.54]; P < 0.001). Among all 381 corridors, 84 were proven to participate in VT re-entry circuits, 83 (99%) of which traversed or were adjacent to LM. In comparison, only 13 (4%) non-VT corridors were adjacent to LM. Critical corridors adjacent to LM displayed lower SD of current compared with noncritical corridors through scar but distant from LM (2.0 [IQR: 1.0 to 3.4] μA vs 8.4 [IQR: 5.5 to 12.8] μA; P < 0.001). CONCLUSIONS Corridors critical to VT circuitry traverse infarcted tissue through or near LM. This association is likely mediated by increased regional resistance and reduced current loss as impulses traverse corridors adjacent to LM.
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Affiliation(s)
- Lingyu Xu
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Mirmilad Khoshknab
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Ronald D Berger
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA; Department of Cardiology, Johns Hopkins University, Baltimore Maryland, USA
| | - Jonathan Chrispin
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA; Department of Cardiology, Johns Hopkins University, Baltimore Maryland, USA
| | - Sanjay Dixit
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Pasquale Santangeli
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - David Callans
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Francis E Marchlinski
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Stefan L Zimmerman
- Department of Radiology and Radiological Sciences, Johns Hopkins University, Baltimore Maryland, USA
| | - Yuchi Han
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Natalia Trayanova
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Benoit Desjardins
- Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | - Saman Nazarian
- Cardiovascular Medicine Division, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
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17
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Groen MHA, van Driel VJHM, Neven K, van Wessel H, de Bakker JMT, Doevendans PAF, Wittkampf FHM, Loh P, van Es R. Multielectrode Contact Measurement Can Improve Long-Term Outcome of Pulmonary Vein Isolation Using Circular Single-Pulse Electroporation Ablation. Circ Arrhythm Electrophysiol 2022; 15:e010835. [PMID: 35917465 PMCID: PMC9384826 DOI: 10.1161/circep.121.010835] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Irreversible electroporation (IRE) ablation is generally performed with multielectrode catheters. Electrode-tissue contact is an important predictor for the success of pulmonary vein (PV) isolation; however, contact force is difficult to measure with multielectrode ablation catheters. In a preclinical study, we assessed the feasibility of a multielectrode impedance system (MEIS) as a predictor of long-term success of PV isolation. In addition, we present the first-in-human clinical experience with MEIS. METHODS In 10 pigs, one PV was ablated based on impedance (MEIS group), and the other PV was solely based on local electrogram information (electrophysiological group). IRE ablations were performed at 200 J. After 3 months, recurrence of conduction was assessed. Subsequently, in 30 patients undergoing PV isolation with IRE, MEIS was evaluated and MEIS contact values were compared to local electrograms. RESULTS In the porcine study, 43 IRE applications were delivered in 19 PVs. Acutely, no reconnections were observed in either group. After 3 months, 0 versus 3 (P=0.21) PVs showed conduction recurrence in the MEIS and electrophysiological groups, respectively. Results from the clinical study showed a significant linear relation was found between mean MEIS value and bipolar dV/dt (r2=0.49, P<0.001), with a slope of 20.6 mV/s per Ohm. CONCLUSIONS Data from the animal study suggest that MEIS values predict effective IRE applications. For the long-term success of electrical PV isolation with circular IRE applications, no significant difference in efficacy was found between ablation based on the measurement of electrode interface impedance and ablation using the classical electrophysiological approach for determining electrode-tissue contact. Experiences of the first clinical use of MEIS were promising and serve as an important basis for future research.
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Affiliation(s)
- Marijn H A Groen
- Division Heart and Lungs, Department of Cardiology, University Medical Center (M.H.A.G., V.J.H.M.v.D., K.N., H.v.W., P.A.F.D., F.H.M.W., P.L., R.v.E.).,Netherlands Heart Institute, Utrecht (M.H.A.G., P.A.F.D.)
| | - Vincent J H M van Driel
- Division Heart and Lungs, Department of Cardiology, University Medical Center (M.H.A.G., V.J.H.M.v.D., K.N., H.v.W., P.A.F.D., F.H.M.W., P.L., R.v.E.).,Department of Cardiology, Haga Teaching Hospital, The Hague, the Netherlands (V.J.H.M.v.D.)
| | - Kars Neven
- Division Heart and Lungs, Department of Cardiology, University Medical Center (M.H.A.G., V.J.H.M.v.D., K.N., H.v.W., P.A.F.D., F.H.M.W., P.L., R.v.E.).,Department of Electrophysiology, Alfried Krupp Krankenhaus, Essen (K.N.).,Department of Medicine, Witten/Herdecke University, Witten, Germany (K.N.)
| | - Harry van Wessel
- Division Heart and Lungs, Department of Cardiology, University Medical Center (M.H.A.G., V.J.H.M.v.D., K.N., H.v.W., P.A.F.D., F.H.M.W., P.L., R.v.E.).,Abbott Medical Nederland B.V., Veenendaal (H.v.W.)
| | - J M T de Bakker
- Heart Center, Department of Experimental Cardiology, Academic Medical Center Amsterdam, the Netherlands (J.M.T.d.B.)
| | - Pieter A F Doevendans
- Division Heart and Lungs, Department of Cardiology, University Medical Center (M.H.A.G., V.J.H.M.v.D., K.N., H.v.W., P.A.F.D., F.H.M.W., P.L., R.v.E.).,Netherlands Heart Institute, Utrecht (M.H.A.G., P.A.F.D.)
| | - Fred H M Wittkampf
- Division Heart and Lungs, Department of Cardiology, University Medical Center (M.H.A.G., V.J.H.M.v.D., K.N., H.v.W., P.A.F.D., F.H.M.W., P.L., R.v.E.)
| | - Peter Loh
- Division Heart and Lungs, Department of Cardiology, University Medical Center (M.H.A.G., V.J.H.M.v.D., K.N., H.v.W., P.A.F.D., F.H.M.W., P.L., R.v.E.)
| | - René van Es
- Division Heart and Lungs, Department of Cardiology, University Medical Center (M.H.A.G., V.J.H.M.v.D., K.N., H.v.W., P.A.F.D., F.H.M.W., P.L., R.v.E.)
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18
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Requirement of larger local impedance reduction for successful lesion formation at carinal area during pulmonary vein isolation. J Interv Card Electrophysiol 2022; 65:509-518. [PMID: 35794439 DOI: 10.1007/s10840-022-01282-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/15/2022] [Indexed: 10/17/2022]
Abstract
PURPOSE Local impedance (LI) measurement from an ablation catheter is useful in predicting lesion size and acute success of pulmonary vein isolation (PVI). The LI variation can be described by absolute LI drop (ΔLID) or ΔLID/initial LI (%LID). We evaluated the utility of these parameters in predicting acute lesion durability during PVI using a novel catheter capable of measuring both LI and contact force (CF). METHODS PVI with a targeted CF, power, and duration was performed in 23 consecutive patients with paroxysmal atrial fibrillation. LI was blinded to operators during ablation. Parameters for each RF application were collected and compared for acute successful lesions and gaps. RESULTS A total of 1633 RF applications including 97 (5.9%) gap lesions were analyzed. Successful lesions were more frequently observed at non-carinal sites and those with higher contact force, FTI, initial LI, and larger variation of LI and generator impedance (GI). Multivariate analysis demonstrated that absolute GI drop (ΔGID) [OR 1.09 (1.04-1.15), p < 0.001], ΔLID [1.12 (1.09-1.16), p < 0.001], ΔGID/initial GI (%GID) [OR 1.04 (1.01-1.07), p = 0.01], and %LID [OR 1.15 (1.12-1.28), p < 0.001] were significantly associated with successful lesions, and carinal site [OR 0.15(0.09-0.24), p < 0.001] was significantly related to gaps. Both ΔLID and %LID equally predicted the acute durability of lesions during PVI. ΔLID ≥ 24Ω and %LID ≥ 15% at the carina, and ΔLID ≥ 21Ω and %LID ≥ 14% at non-carinal sites significantly predicted acute successful lesions with negative predictive values of 93-99%. CONCLUSIONS Both ΔLID and %LID were equally useful in predicting acute successful lesions during PVI. Larger cut-off values should be applied to carinal sites.
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Saraf K, Black N, Garratt CJ, Muhyaldeen SA, Morris GM. Local impedance-guided ablation and ultra-high density mapping versus conventional or contact force-guided ablation with mapping for treatment of cavotricuspid isthmus dependent atrial flutter. Indian Pacing Electrophysiol J 2022; 22:188-194. [PMID: 35427782 PMCID: PMC9263660 DOI: 10.1016/j.ipej.2022.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 03/01/2022] [Accepted: 03/30/2022] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION - Local impedance (LI) guided ablation as a method of judging lesion effectiveness for cavotricuspid isthmus dependent atrial flutter (CTI-AFL), and ultra-high density (UHD) mapping when breakthrough occurred across an ablation line has not previously been assessed. METHODS This retrospective observational study evaluated patients undergoing CTI-AFL ablation using conventional, contact force (CF) and LI guided strategies. Ablation metrics were collected, and in the LI cohort, the use of UHD mapping for breakthrough evaluated. RESULTS 30 patients were included, 10 per group. Mean total ablation time was significantly shorter with LI (3.2 ± 1.3min) vs conventional (5.6 ± 2.7min) and CF (5.7 ± 2.0min, p = 0.0042). Time from start of ablation to CTI block was numerically shorter with LI (14.2 ± 8.0min) vs conventional and CF (19.7 ± 14.1 and 22.5 ± 19.1min, p = 0.4408). Mean lesion duration was significantly shorter with LI, but there were no differences in the number of lesions required to achieve block, procedural success, complication rates or recurrence. 15/30 patients did not achieve block following first-pass ablation. UHD mapping rapidly identified breakthrough in the five LI patients, including epicardial-endocardial breakthrough (EEB). CONCLUSION - The use of LI during ablation for real-time lesion assessment was as efficacious as the conventional and CF methods. UHD mapping rapidly identified breakthrough, including EEB.
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Affiliation(s)
- Karan Saraf
- Division of Cardiovascular Sciences, The University of Manchester, Oxford Road, Manchester, M139PL, UK; Manchester Heart Centre, Manchester University NHS Foundation Trust, Oxford Road, Manchester, M139WL, UK
| | - Nicholas Black
- Division of Cardiovascular Sciences, The University of Manchester, Oxford Road, Manchester, M139PL, UK; Royal Oldham Hospital, Rochdale Road, Oldham, OL1 2JH, UK
| | - Clifford J Garratt
- Division of Cardiovascular Sciences, The University of Manchester, Oxford Road, Manchester, M139PL, UK; Manchester Heart Centre, Manchester University NHS Foundation Trust, Oxford Road, Manchester, M139WL, UK
| | - Sahrkaw A Muhyaldeen
- Manchester Heart Centre, Manchester University NHS Foundation Trust, Oxford Road, Manchester, M139WL, UK
| | - Gwilym M Morris
- Division of Cardiovascular Sciences, The University of Manchester, Oxford Road, Manchester, M139PL, UK; Manchester Heart Centre, Manchester University NHS Foundation Trust, Oxford Road, Manchester, M139WL, UK.
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20
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Sánchez-Muñoz EJ, Berjano E, González-Suárez A. Computer simulations of consecutive radiofrequency pulses applied at the same point during cardiac catheter ablation: Implications for lesion size and risk of overheating. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2022; 220:106817. [PMID: 35468542 DOI: 10.1016/j.cmpb.2022.106817] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 04/12/2022] [Accepted: 04/14/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND AND OBJECTIVES To study temperature distribution and lesion size during two repeated radiofrequency (RF) pulses applied at the same point in the context of RF cardiac ablation (RFCA). METHODS An in-silico RFCA model accounting for reversible and irreversible changes in myocardium electrical properties due to RF-induced heating. Arrhenius damage model to estimate lesion size during the application of two 20 W pulses at intervals (INT) of from 5 to 70 s. We considered two pulse durations: 20 s and 30 s. RESULTS INT has a significant effect on lesion size and maximum tissue temperature (TMAX). The shorter the INT the greater the increase in lesion size after the second pulse but also the greater the TMAX. If the second pulse is applied almost immediately (INT=5 s), depth increases 1.4 mm and 1.5 mm for pulses of 20 s and 30 s, respectively. If INT is longer than 30 s it increases 1.1 mm and 1.3 mm for pulses of 20 s and 30 s, respectively. While a single 20 s pulse causes TMAX=79 ºC, a second pulse produces values of from 92 to 96 ºC (the higher the temperature the shorter the INT). For 30 s pulses, TMAX=93 ºC for a single pulse, and varied from 98 to 104 ºC for a second pulse. CONCLUSIONS Applying a second RF pulse at the same ablation site increases lesion depth by 1 - 1.5 mm more than a single pulse and could lead to higher temperatures (up to 17 ºC). Both lesion depth and maximum tissue temperature increased at shorter inter-pulse intervals, which could cause clinical complications from overheating such as steam pops.
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Affiliation(s)
| | - Enrique Berjano
- BioMIT, Department of Electronic Engineering, Universitat Politècnica de València, Valencia, Spain
| | - Ana González-Suárez
- Electrical and Electronic Engineering, National University of Ireland Galway, Ireland; Translational Medical Device Lab, National University of Ireland Galway, Ireland.
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21
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Local Impedance Drop Predicts Durable Conduction Block in Patients With Paroxysmal Atrial Fibrillation. JACC Clin Electrophysiol 2022; 8:595-604. [PMID: 35589172 DOI: 10.1016/j.jacep.2022.01.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/03/2022] [Accepted: 01/05/2022] [Indexed: 11/23/2022]
Abstract
OBJECTIVES This analysis was performed to evaluate the transition of local impedance (LI) drop during pulmonary vein isolation (PVI) to durable block and mature lesion formation based on 3-month mapping procedures. BACKGROUND A radiofrequency catheter measuring LI has been shown to be effective for performing PVI in patients with paroxysmal atrial fibrillation. Previous analysis has demonstrated LI drop to be predictive of pulmonary vein segment conduction block during an atrial fibrillation ablation procedure. METHODS Fifty-eight patients who had undergone LI-blinded de novo PVI returned for a 3-month mapping procedure. PVI ablation circles were divided into 16 anatomic segments for classification (durable block or gap), and the median LI drop within segments with an interlesion distance of ≤6 mm was compared. A total of 51 data sets met the criteria for segmental analysis of LI performance. RESULTS At the 3-month procedure, PV connection was confirmed in at least 1 PV segment in 35 of the included patients. LI drop outperformed generator impedance drop as a predictor of durable conduction block (area under the receiver-operating characteristic curve: 0.79 vs 0.68; P = 0.003). Optimal LI drops were identified by left atrial region (anterior/superior: 16.9 Ω [sensitivity: 69.1%; specificity: 85.0%; positive predictive value for durable conduction block: 97.7%]; posterior/inferior:14.2 Ω [sensitivity: 73.8%; specificity: 78.3%; positive predictive value: 96.9%]). Starting LI before radiofrequency (RF) application was significantly different among healthy, gap, and mature scar tissue and was also a contributing factor to achieving an optimal LI drop (85.2% of RF applications with a starting LI of ≥110 Ω achieved the optimal regional drop or greater). CONCLUSIONS LI drop is predictive of durable PV segment isolation. Preablation starting LI is associated with the magnitude of LI drop. These findings suggest that a regional approach to RF ablation guided by LI combined with careful interlesion distance control may be beneficial in patients with paroxysmal atrial fibrillation (Electrical Coupling Information From the Rhythmia HDx System and DirectSense Technology in Subjects With Paroxysmal Atrial Fibrillation [LOCALIZE]; NCT03232645).
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22
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Comparison of two catheters measuring local impedance: local impedance variation vs lesion characteristics and steam pops. J Interv Card Electrophysiol 2022; 65:419-428. [PMID: 35438394 DOI: 10.1007/s10840-022-01214-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 03/31/2022] [Indexed: 10/18/2022]
Abstract
PURPOSE The size of the distal electrode and the method of measuring local impedance (LI) are different between the IntellaNav MiFi-OI™ (MiFi-OI) and IntellaNav STABLE POINT™ (SP) catheters. We investigated the impact of these differences on LI, efficacy, and safety of radiofrequency (RF) applications. METHODS RF applications at a range of powers (30 W, 40 W, and 50 W), contact forces (10 g and 20 g), and durations (10-120 s) were performed in excised porcine hearts (N = 48). LI variation was defined by δLI-drop (= initial LI - post-RF LI) and %LI-drop (= δLI-drop/initial LI) × 100, and the relationship between lesion characteristics and LI variation was compared. RESULTS A total of 576 lesions were examined. Although absolute δLI-drop during RF applications was significantly larger for the SP than MiFi-OI catheter (47[31-65]ohm for SP vs 37[24-51]ohm for MiFi-OI, p < 0.0001), %LI-drop was similar (23.3 [15.5-30.6]% in SP vs 24.9[17.3-32.5]% in MiFi-OI, p = 0.10). Although lesions produced by both catheters were similarly correlated with LI variation, the SP catheter produced generally larger lesions (depth; 5.0 [3.7-6.1]mm vs 4.7 [3.3-6.0]mm, p = 0.06; surface areas, 46.9 [36.8-58.8]mm2 vs 44.7 [34.3-55.5]mm2, p = 0.02; volume, 321 [165-533]mm3 vs 265[141-471]mm3, p = 0.02). Steam pops were similarly observed with both catheters. In both catheters, %LI-drop was superior to δLI-drop in correlation to lesion size (p < 0.0001) and in predicting steam pops (p < 0.01). CONCLUSIONS Although no difference in safety profile is observed between MiFi-OI and SP catheters, the SP catheter produces larger lesions. %LI-drop is superior to δLI-drop in correlation to lesion size and in predicting steam pops as well as in normalizing the difference between catheters.
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23
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Yasumoto K, Egami Y, Kawanami S, Sugae H, Ukita K, Kawamura A, Nakamura H, Matsuhiro Y, Tsuda M, Okamoto N, Matsunaga-Lee Y, Yano M, Nishino M, Tanouchi J. The correlation between local impedance drop and catheter contact in clinical pulmonary vein isolation use. Pacing Clin Electrophysiol 2022; 45:984-992. [PMID: 35363376 DOI: 10.1111/pace.14500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 02/27/2022] [Accepted: 03/18/2022] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Local impedance (LI) drop during radiofrequency (RF) application is monitored to assess the lesion formation. Recently, a novel ablation catheter has been introduced to clinical setting, which is capable of monitoring LI and catheter contact parameters including contact force (CF) and contact angle (CA). This study aimed to clarify the correlation between LI drop and catheter contact parameters. METHODS AND RESULTS This prospective study included 15 paroxysmal atrial fibrillation (AF) patients who underwent initial pulmonary vein isolation (PVI). First-pass encircling point-by-point PV ablation was performed by using a 4.5-mm irrigated ablation catheter, with monitoring LI, CF, and CA. RF energy was applied for 30 sec at each site with 30W. Stable ablation points were analyzed to examine the correlation between LI drop and catheter contact parameters. Among 903 ablation points, 499 stable ablation points (55.2%) were analyzed. CA showed good correlation with LI drop (ρ = 0.418, P<0.001). Maximum CF, minimum CF, average CF, and initial CF all showed weak correlation with LI drop (ρ = 0.201, P<0.001; ρ = 0.224, P<0.001; ρ = 0.258, P<0.001; and ρ = 0.212, P<0.001, respectively). Multivariate analysis demonstrated that CA was an independent factor of LI drop among the catheter contact parameters (β = 0.139, 95%CI = 0.111-0.167, P<0.001). The LI drop in the blocked segments was significantly higher than that in the electrical conduction gap segments (27.3 ± 9.8 Ω vs. 19.6 ± 6.4 Ω, P<0.001) CONCLUSION: In clinical PVI use, both CF and CA were correlated with LI drop. More parallel CA could induce higher LI drop, which may lead to effective lesion formation. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Koji Yasumoto
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Yasuyuki Egami
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Shodai Kawanami
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Hiroki Sugae
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Kohei Ukita
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Akito Kawamura
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Hitoshi Nakamura
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Yutaka Matsuhiro
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Masaki Tsuda
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Naotaka Okamoto
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | | | - Masamichi Yano
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Masami Nishino
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
| | - Jun Tanouchi
- Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan
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24
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Ramak R, Lipartiti F, Mojica J, Monaco C, Bisignani A, Eltsov I, Sorgente A, Capulzini L, Paparella G, Deruyter B, Iacopino S, Motoc AI, Luchian ML, Osorio TG, Overeinder I, Bala G, Almorad A, Ströker E, Sieira J, Jordaens L, Brugada P, de Asmundis C, Chierchia GB. Comparison between the novel diamond temp and the classical 8-mm tip ablation catheters in the setting of typical atrial flutter. J Interv Card Electrophysiol 2022; 64:751-757. [PMID: 35239069 DOI: 10.1007/s10840-022-01152-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 02/07/2022] [Indexed: 01/10/2023]
Abstract
PURPOSE Radiofrequency (RF) catheter ablation is widely accepted as a first-line therapy for cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL). The novel DiamondTemp (DT) catheter with temperature feedback during RF ablation has been released recently on the market. The purpose of this study was to evaluate the impact of DiamondTemp (DT) technology on ablation efficiency during AFL. METHODS In this single-center study, 30 consecutive patients with typical AFL indicated to ablation of CTI were included. The first 15 patients underwent CTI ablation using 8-mm tip catheter, and the following 15 patients underwent temperature-controlled RF ablation using DT catheter. The endpoints were number and mean total duration of RF applications, mean temperature reached in the setting of CTI, procedural times, and fluoroscopy times. RESULTS There were no significant differences between the two groups concerning baseline characteristics. Mean duration of the each application (71.5 s ± 30.6 vs 12.4 s ± 13.2, p value < 0.001), mean total duration of RF applications (517,73 s ± 377,96 vs 112,8 s ± 43,58; p value < 0.001), procedural times (51.6 min ± 24.2 vs 38.6 ± 8.2; p = 0.03), and fluoroscopy times (16.2 min ± 10.2 vs 8 min ± 4.24; p = 0.005) were longer in the 8-mm ablation catheter group. Mean temperature measurements (51.9 °C ± 3.59 vs 56.7 °C ± 3.34, p value < 0.003) were as well lower in the 8-mm ablation catheter group. CONCLUSIONS Catheter ablation of CTI-dependent AFL by means of DT resulted in a significant reduction of total and single application RF delivery time, procedure, and fluoroscopy times.
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Affiliation(s)
- Robbert Ramak
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Felicia Lipartiti
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Joerelle Mojica
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Cinzia Monaco
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Antonio Bisignani
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Ivan Eltsov
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Antonio Sorgente
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Lucio Capulzini
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Gaetano Paparella
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Bernard Deruyter
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Saverio Iacopino
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Andreea Iulia Motoc
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Maria Luiza Luchian
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Thiago Guimaraes Osorio
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Ingrid Overeinder
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Gezim Bala
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Alexandre Almorad
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Erwin Ströker
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Juan Sieira
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Luc Jordaens
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Pedro Brugada
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Carlo de Asmundis
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium
| | - Gian-Battista Chierchia
- Heart Rhythm Management Center, Postgraduate Program in Cardiac Electrophysiology and Pacing, European Reference Networks Guard-Heart, Universitair Ziekenhuis Brussel-Vrije Universiteit Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium.
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25
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Sasaki T, Nakamura K, Minami K, Take Y, Nakatani Y, Miki Y, Goto K, Kaseno K, Yamashita E, Koyama K, Naito S. Local impedance measurements during contact force‐guided cavotricuspid isthmus ablation for predicting an effective radiofrequency ablation. J Arrhythm 2022; 38:245-252. [PMID: 35387143 PMCID: PMC8977576 DOI: 10.1002/joa3.12680] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/05/2022] [Accepted: 01/16/2022] [Indexed: 01/13/2023] Open
Abstract
Background An ablation catheter capable of contact force (CF) and local impedance (LI) monitoring (IntellaNav StablePoint, Boston Scientific) has been recently launched. We evaluated the relationship between the CF and LI values during radiofrequency catheter ablation (RFCA) along the cavotricuspid isthmus (CTI). Methods Fifty consecutive subjects who underwent a CTI‐RFCA using IntellaNav StablePoint catheters were retrospectively studied. The initial CF and LI at the start of the RF applications and mean CF and minimum LI during the RF applications were measured. The absolute and percentage LI drops were calculated as the difference between the initial and minimum LIs and 100 × absolute LI drop/initial LI, respectively. Results We analyzed 602 first‐pass RF applications. A weak correlation was observed between the initial CF and LI (r = 0.13) and between the mean CF and LI drops (r = 0.22). The initial LI and absolute and percentage LI drops were greater at effective ablation sites than ineffective ablation sites (median, 151 vs. 138 Ω, 22 vs. 14 Ω, and 14.4% vs. 9.9%; p < .001), but the initial and mean CF did not differ. At optimal cutoffs of 21 Ω and 10.8% for the absolute and percentage LI drops according to the receiver‐operating characteristic analysis, the sensitivity, and specificity for predicting an effective ablation were 57.4% and 88.9% and 80.0%, and 61.1%, respectively. Conclusions The effective sites during the CF‐guided CTI‐RFCA had greater initial LI and LI drops than the ineffective sites. Absolute and percentage LI drops of 21 Ω and 10.8% may be appropriate targets for an effective ablation.
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Affiliation(s)
- Takehito Sasaki
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Kohki Nakamura
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Kentaro Minami
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Yutaka Take
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Yosuke Nakatani
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Yuko Miki
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Koji Goto
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Kenichi Kaseno
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Eiji Yamashita
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Keiko Koyama
- Division of Radiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
| | - Shigeto Naito
- Division of Cardiology Gunma Prefectural Cardiovascular Center Maebashi City Japan
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26
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Gutbrod SR, Shuros A, Koya V, Alexander-Curtis M, Lehn L, Miklos K, Mounsey JP, Meyers JD. Improved Ablation Efficiency in PVI Guided by Contact Force and Local Impedance: Chronic Canine Model. Front Physiol 2022; 12:808541. [PMID: 35082695 PMCID: PMC8784686 DOI: 10.3389/fphys.2021.808541] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/13/2021] [Indexed: 11/13/2022] Open
Abstract
Background: The purpose of this study was to assess the effect local impedance (LI) has on an ablation workflow when combined with a contact force (CF) ablation catheter. Methods: Left pulmonary vein isolation was performed in an in vivo canine model (N = 8) using a nominal (30 W) or an elevated (50 W) power strategy with a CF catheter. The catheter was enabled to measure LI prior to and during ablation. LI was visible for only one of the vein isolations. Results: Chronic block was achieved in all animals when assessed 30 ± 5 days post-ablation procedure with a median LI drop during RF ranging from 23.0 to 34.0 Ω. In both power cohorts, the median radiofrequency (RF) duration decreased if LI was visible to the operator (30 W only CF: 17.0 s; 30 W CF + LI: 14.0 s, p = 0.009; 50 W only CF: 6.0 s; 50 W CF + LI: 4.0 s, p = 0.019). An inverse relationship between the LI prior to RF delivery and the RF duration required to achieve an effective lesion was observed. There was no correlation between the magnitude of the applied force and the drop in LI, once at least 5 g was achieved. Conclusions: An elevated power strategy with the context of CF and LI led to the most efficient titration of successful RF energy delivery. The combination of feedback allows for customization of the ablation strategy based on local tissue variation rather than a uniform approach that could potentially lead to overtreatment. Higher LI drops were more readily achievable when an elevated power strategy was utilized, especially in conditions where the catheter was coupled against tissue with low resistivity. Clinical study is warranted to determine if there is an additive safety benefit to visualizing the dynamics of the tissue response to RF energy with LI when an elevated power strategy is used.
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Affiliation(s)
| | - Allan Shuros
- Boston Scientific Corp., Marlborough, MA, United States
| | - Vijay Koya
- Boston Scientific Corp., Marlborough, MA, United States
| | | | - Lauren Lehn
- Boston Scientific Corp., Marlborough, MA, United States
| | | | - John Paul Mounsey
- Department of Internal Medicine and Cardiovascular Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Jason D Meyers
- Department of Clinical Cardiac Electrophysiology, Iowa Heart Center, West Des Moines, IA, United States
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27
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Unger LA, Schicketanz L, Oesterlein T, Stritt M, Haas A, Martínez Antón C, Schmidt K, Doessel O, Luik A. Local Electrical Impedance Mapping of the Atria: Conclusions on Substrate Properties and Confounding Factors. Front Physiol 2022; 12:788885. [PMID: 35140628 PMCID: PMC8819079 DOI: 10.3389/fphys.2021.788885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 12/27/2021] [Indexed: 11/13/2022] Open
Abstract
The treatment of atrial fibrillation and other cardiac arrhythmias as a major cause of cardiovascular hospitalization has remained a challenge predominantly for patients with severely remodeled substrate. Individualized ablation strategies are extremely important both for pulmonary vein isolation and subsequent ablations. Current approaches to identifying arrhythmogenic regions rely on electrogram-based features such as activation time and voltage. Novel technologies now enable clinical assessment of the local impedance as tissue property. Previous studies demonstrated its use for ablation monitoring and indicated its potential to differentiate healthy substrate, scar, and pathological tissue. This study investigates the potential of local electrical impedance-based substrate mapping of the atria for human in-vivo data. The presented pipeline for impedance mapping particularly contains options for dealing with undesirable effects originating from cardiac motion, catheter motion, or proximity to other intracardiac devices. Bloodpool impedance was automatically determined as a patient-specific reference. Full-chamber, left atrial impedance maps were drawn up from interpolating the measured impedances to the atrial endocardium. Finally, the origin and magnitude of oscillations of the raw impedance recording were probed into. The most dominant reason for exclusion of impedance samples was the loss of endocardial contact. With median elevations above the bloodpool impedance between 29 and 46 Ω, the impedance within the pulmonary veins significantly exceeded the remaining atrial walls presenting median elevations above the bloodpool impedance between 16 and 20 Ω. Previous ablation lesions were distinguished from their surroundings by a significant drop in local impedance while the corresponding regions did not differ for the control group. The raw impedance was found to oscillate with median amplitudes between 6 and 17 Ω depending on the patient. Oscillations were traced back to an interplay of atrial, ventricular, and respiratory motion. In summary, local impedance measurements demonstrated their capability to distinguish pathological atrial tissue from physiological substrate. Methods to limit the influence of confounding factors that still hinder impedance mapping were presented. Measurements at different frequencies or the combination of multiple electrodes could lead to further improvement. The presented examples indicate that electrogram- and impedance-based substrate mapping have the potential to complement each other toward better patient outcomes in future.
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Affiliation(s)
- Laura Anna Unger
- Institute of Biomedical Engineering, Department of Electrical Engineering and Information Technology, Karlsruhe Institute of Technology, Karlsruhe, Germany
- *Correspondence: Laura Anna Unger
| | - Leonie Schicketanz
- Institute of Biomedical Engineering, Department of Electrical Engineering and Information Technology, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | | | - Michael Stritt
- Institute of Biomedical Engineering, Department of Electrical Engineering and Information Technology, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Annika Haas
- Medizinische Klinik IV, Städtisches Klinikum Karlsruhe, Academic Teaching Hospital of the University of Freiburg, Karlsruhe, Germany
| | - Carmen Martínez Antón
- Institute of Biomedical Engineering, Department of Electrical Engineering and Information Technology, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Kerstin Schmidt
- Medizinische Klinik IV, Städtisches Klinikum Karlsruhe, Academic Teaching Hospital of the University of Freiburg, Karlsruhe, Germany
| | - Olaf Doessel
- Institute of Biomedical Engineering, Department of Electrical Engineering and Information Technology, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Armin Luik
- Medizinische Klinik IV, Städtisches Klinikum Karlsruhe, Academic Teaching Hospital of the University of Freiburg, Karlsruhe, Germany
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28
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Matsuura G, Fukaya H, Ogawa E, Kawakami S, Mori H, Saito D, Sato T, Nakamura H, Ishizue N, Oikawa J, Kishihara J, Niwano S, Ako J. Catheter contact angle influences local impedance drop during radiofrequency catheter ablation: Insight from a porcine experimental study with 2 different LI-sensing catheters. J Cardiovasc Electrophysiol 2022; 33:380-388. [PMID: 35018687 DOI: 10.1111/jce.15356] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/23/2021] [Accepted: 01/01/2022] [Indexed: 11/26/2022]
Abstract
BACKGROUND Local impedance (LI) can indirectly measure catheter contact and tissue temperature during radiofrequency catheter ablation (RFCA). However, data on the effects of catheter contact angle on LI parameters are scarce. This study aimed to evaluate the influence of catheter contact angle on LI changes and lesion size with 2 different LI-sensing catheters in a porcine experimental study. METHODS Lesions were created by the INTELLANAV MiFi™ OI (MiFi) and the INTELLANAV STABLEPOINT™ (STABLEPOINT). RFCA was performed with 30 watts and a duration of 30 seconds. The CF (0, 5, 10, 20, and 30 g) and catheter contact angle (30°, 45°, and 90°) were changed in each set (n=8 each). The LI rise, LI drop, and lesion size were evaluated. RESULTS The LI rise increased as CF increased. There was no angular dependence with the LI rise under all CFs in the MiFi. On the other hand, the LI rise at 90° was lower than at 30° under 5 and 10 g of CF in STABLEPOINT. The LI drop increased as CF increased. Regarding the difference in catheter contact angles, the LI drop at 90° was lower than that at 30° for both catheters. The maximum lesion widths and surface widths were smaller at 90° than at 30°, whereas there were no differences in lesion depths. CONCLUSION The LI drop and lesion widths at 90° were significantly smaller than those at 30°, although the lesion depths were not different among the 3 angles for the MiFi and STABLEPOINT. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Gen Matsuura
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Hidehira Fukaya
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Emiyu Ogawa
- Department of Medical Engineering and Technology, Kitasato University School of Allied Health Sciences, Sagamihara, Kanagawa, Japan
| | - Sota Kawakami
- Department of Medical Engineering and Technology, Kitasato University School of Allied Health Sciences, Sagamihara, Kanagawa, Japan
| | - Hitoshi Mori
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Saitama, Japan
| | - Daiki Saito
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Tetsuro Sato
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Hironori Nakamura
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Naruya Ishizue
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Jun Oikawa
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Jun Kishihara
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Shinichi Niwano
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Junya Ako
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
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29
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Solimene F, De Sanctis V, Maggio R, Malacrida M, Segreti L, Anselmino M, Schillaci V, Mantica M, Scaglione M, Dello Russo A, Cauti FM, Zingarini G, Pandozi C, Cavaiani M, Ferraro A, Maglia G, Stabile G. When local impedance meets contact force: preliminary experience from the CHARISMA registry. J Interv Card Electrophysiol 2022; 63:749-758. [PMID: 35322330 PMCID: PMC9151535 DOI: 10.1007/s10840-022-01163-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 02/16/2022] [Indexed: 12/14/2022]
Abstract
PURPOSE Highly localized impedance (LI) measurements during atrial fibrillation (AF) ablation have emerged as a viable real-time indicator of tissue characteristics and the consequent durability of the lesions created. We investigated the impact of catheter-tissue contact force (CF) on LI behavior during pulmonary vein isolation (PVI). METHODS Forty-five consecutive patients of the CHARISMA registry undergoing de novo AF radiofrequency (RF) catheter ablation with a novel open-irrigated-tip catheter endowed with CF and LI measurement capabilities (Stablepoint™ catheter, Boston Scientific) were included. RESULTS A total of 2895 point-by-point RF applications were analyzed (RF delivery time (DT) = 8.7±4s, CF = 13 ±±8 g, LI drop = 23 ±±7 Ω). All PVs were successfully isolated in an overall procedure time of 118 ±±34 min (fluoroscopy time = 13 ±±8 min). The magnitude of LI drop weakly correlated with CF (r = 0.13, 95% confidence interval (CI): 0.09 to 0.16, p < 0.0001), whereas both CF and LI drop inversely correlated with DT (r = -0.26, 95%CI: -0.29 to -0.22, p < 0.0001 for CF; r = -0.36, 95%CI: -0.39 to -0.33, p < 0.0001 for LI). For each 10 g of CF, LI drop markedly increased from 22.4 ± 7 Ω to 24.0 ± 8 Ω at 5 to 25 g CF intervals (5-14 g of CF vs 15-24 g of CF, p < 0.0001), whereas it showed smooth transition over 25 g (24.8 ± 7Ω at ≥ 25 g CF intervals, p = 0.0606 vs 15-24 g of CF). No major complications occurred during the procedures or within 30 days. CONCLUSIONS CF significantly affects LI drop and probable consequent lesion formation during RF PVI. The benefit of higher contact (> 25 g) between the catheter and the tissue appears to have less impact on LI drop. TRIAL REGISTRATION Catheter Ablation of Arrhythmias With High Density Mapping System in the Real World Practice (CHARISMA). URL: http://clinicaltrials.gov/ Identifier: NCT03793998.
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Affiliation(s)
| | - Valerio De Sanctis
- Department of Cardiac Electrophysiology and Pacing, Istituto Clinico Sant'Ambrogio, Via Luigi Giuseppe Faravelli, 16, 20149, Milan, Italy.
| | | | | | - Luca Segreti
- Second Division of Cardiology, Cardiac-Thoracic-Vascular Department, New Santa Chiara Hospital, Azienda Ospedaliero Universitaria Pisana, Pisa, Italy
| | - Matteo Anselmino
- Division of Cardiology, "Città della Salute e della Scienza di Torino" Hospital, Department of Medical Sciences, University of Turin, Turin, Italy
| | | | - Massimo Mantica
- Department of Cardiac Electrophysiology and Pacing, Istituto Clinico Sant'Ambrogio, Via Luigi Giuseppe Faravelli, 16, 20149, Milan, Italy
| | | | - Antonio Dello Russo
- Cardiology and Arrhythmology Clinic, Marche Polytechnic University, Ancona, Italy
| | - Filippo Maria Cauti
- Arrhythmology Unit, Ospedale San Giovanni Calibita, Fatebefratelli, Isola Tiberina, Rome, Italy
| | | | - Claudio Pandozi
- Division of Cardiology, San Filippo Neri Hospital, Rome, Italy
| | | | | | | | - Giuseppe Stabile
- Clinica Montevergine, Avellino, Mercogliano, Italy
- Anthea Hospital, Bari, Italy
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30
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Mulder MJ, Kemme MJB, Allaart CP. Radiofrequency ablation to achieve durable pulmonary vein isolation. Europace 2021; 24:874-886. [PMID: 34964469 DOI: 10.1093/europace/euab279] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Indexed: 11/13/2022] Open
Abstract
Pulmonary vein isolation (PVI) by radiofrequency (RF) ablation is an important alternative to antiarrhythmic drugs in the treatment of symptomatic atrial fibrillation. However, the inability to consistently achieve durable isolation of the pulmonary veins hampers the long-term efficacy of PVI procedures. The large number of factors involved in RF lesion formation and the complex interplay of these factors complicate reliable creation of durable and transmural ablation lesions. Various surrogate markers of ablation lesion formation have been proposed that may provide information on RF lesion completeness. Real-time assessment of these surrogates may aid in the creation of transmural ablation lesions, and therefore, holds potential to decrease the risk of PV reconnection and consequent post-PVI arrhythmia recurrence. Moreover, titration of energy delivery until lesions is transmural may prevent unnecessary ablation and subsequent adverse events. Whereas several surrogate markers of ablation lesion formation have been described over the past decades, a 'gold standard' is currently lacking. This review provides a state-of-the-art overview of ablation strategies that aim to enhance durability of RF-PVI, with special focus on real-time available surrogates of RF lesion formation in light of the biophysical basis of RF ablation.
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Affiliation(s)
- Mark J Mulder
- Department of Cardiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Michiel J B Kemme
- Department of Cardiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Cornelis P Allaart
- Department of Cardiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
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31
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Zhao X, Ziv O, Mohammadpour R, Crosby B, Hoyt WJ, Jenkins MW, Snyder C, Hendon C, Laurita KR, Rollins AM. Polarization-sensitive optical coherence tomography monitoring of percutaneous radiofrequency ablation in left atrium of living swine. Sci Rep 2021; 11:24330. [PMID: 34934120 PMCID: PMC8692484 DOI: 10.1038/s41598-021-03724-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 12/06/2021] [Indexed: 11/12/2022] Open
Abstract
Radiofrequency ablation (RFA) is commonly used to treat atrial fibrillation (AF). However, the outcome is often compromised due to the lack of direct real-time feedback to assess lesion transmurality. In this work, we evaluated the ability of polarization-sensitive optical coherence tomography (PSOCT) to measure cardiac wall thickness and assess RF lesion transmurality during left atrium (LA) RFA procedures. Quantitative transmural lesion criteria using PSOCT images were determined ex vivo using an integrated PSOCT-RFA catheter and fresh swine hearts. LA wall thickness of living swine was measured with PSOCT and validated with a micrometer after harvesting the heart. A total of 38 point lesions were created in the LA of 5 living swine with the integrated PSOCT-RFA catheter using standard clinical RFA procedures. For all lesions with analyzable PSOCT images, lesion transmurality was assessed with a sensitivity of 89% (17 of 19 tested positive) and a specificity of 100% (5 of 5 tested negative) using the quantitative transmural criteria. This is the first report of using PSOCT to assess LA RFA lesion transmurality in vivo. The results indicate that PSOCT may potentially provide direct real-time feedback for LA wall thickness and lesion transmurality.
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Affiliation(s)
- Xiaowei Zhao
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Ohad Ziv
- School of Medicine, Case Western Reserve University, Cleveland, OH, USA
- Heart and Vascular Research Center, MetroHealth Medical Center, Cleveland, OH, USA
| | | | - Benjamin Crosby
- Department of Chemistry, Case Western Reserve University, Cleveland, OH, USA
| | - Walter J Hoyt
- Department of Pediatrics, Ochsner Health, New Orleans, LA, USA
| | - Michael W Jenkins
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, USA
| | - Christopher Snyder
- School of Medicine, Case Western Reserve University, Cleveland, OH, USA
- The Congenital Heart Collaborative, Rainbow Babies and Children's Hospital, Cleveland, OH, USA
| | - Christine Hendon
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Kenneth R Laurita
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- Heart and Vascular Research Center, MetroHealth Medical Center, Cleveland, OH, USA
| | - Andrew M Rollins
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA.
- School of Medicine, Case Western Reserve University, Cleveland, OH, USA.
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32
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Chu GS, Calvert P, Futyma P, Ding WY, Snowdon R, Gupta D. Local impedance for the optimization of radiofrequency lesion delivery: A review of bench and clinical data. J Cardiovasc Electrophysiol 2021; 33:389-400. [PMID: 34921465 DOI: 10.1111/jce.15335] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 11/11/2021] [Accepted: 12/05/2021] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Radiofrequency catheter ablation is a cornerstone of treatment for many cardiac arrhythmias. Progression in three-dimensional mapping and contact-force sensing technologies have improved our capability to achieve success, but challenges still remain. METHODS In this article, we discuss the importance of overall circuit impedance in radiofrequency lesion formation. This is followed by a review of the literature regarding recently developed "local impedance" technology and its current and future potential applications and limitations, in the context of established surrogate markers currently used to infer effective ablation. RESULTS We discuss the role of local impedance in assessing myocardial substrate, as well as its role in clinical studies of ablation. We also discuss safety considerations, limitations and ongoing research. CONCLUSION Local impedance is a novel tool which has the potential to tailor ablation in a manner distinct from other established metrics.
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Affiliation(s)
- Gavin S Chu
- Department of Cardiology, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK.,Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Peter Calvert
- Department of Cardiology, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK.,Research Unit, Liverpool Centre for Cardiovascular Science, University of Liverpool, Liverpool, UK
| | - Piotr Futyma
- Department of Cardiology, Medical College of the University of Rzeszów, St. Joseph's Heart Rhythm Center, Rzeszów, Poland, Rzeszów, Poland
| | - Wern Yew Ding
- Department of Cardiology, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK.,Research Unit, Liverpool Centre for Cardiovascular Science, University of Liverpool, Liverpool, UK
| | - Richard Snowdon
- Department of Cardiology, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK
| | - Dhiraj Gupta
- Department of Cardiology, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK.,Research Unit, Liverpool Centre for Cardiovascular Science, University of Liverpool, Liverpool, UK
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33
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Short-Time Impedance Spectroscopy Using a Mode-Switching Nonsinusoidal Oscillator: Applicability to Biological Tissues and Continuous Measurement. SENSORS 2021; 21:s21216951. [PMID: 34770258 PMCID: PMC8587290 DOI: 10.3390/s21216951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 10/13/2021] [Accepted: 10/18/2021] [Indexed: 01/04/2023]
Abstract
Herein, we propose an impedance spectroscopy method using a mode-switching nonsinusoidal oscillator and apply this method for measuring the impedance of biological tissues and continuous impedance measurement. To obtain impedance spectra over a wide frequency range, we fabricated a novel nonsinusoidal oscillator incorporating binary counters and analog switches. This oscillator could periodically switch oscillation frequency through the mode switching of the feedback resistor. From the oscillation waveform at each oscillation frequency of this circuit (oscillator), we determined the impedance spectrum of a measured object using the discrete-time Fourier transform. Subsequently, we obtained the broad impedance spectrum of the measured object by merging odd-order harmonic spectral components up to the 19th order for each oscillation frequency. From the measured spectrum, the resistive and capacitive components of the circuit simulating bioimpedance were estimated with high accuracy. Moreover, the proposed method was used to measure the impedance of porcine myocardium; changes in the impedance spectrum of the myocardial tissue due to coagulation could be measured. Furthermore, rapid variations in the resistance value of a CdS photocell could be continuously measured using the proposed method.
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34
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Tsutsui K, Kawano D, Mori H, Kato R, Ikeda Y, Sumitomo N, Fukaya H, Iwanaga S, Nakano S, Muramatsu T, Matsumoto K. Characteristics and optimal ablation settings of a novel, contact-force sensing and local impedance-enabled catheter in an ex vivo perfused swine ventricle model. J Cardiovasc Electrophysiol 2021; 32:3187-3194. [PMID: 34559441 DOI: 10.1111/jce.15253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 08/25/2021] [Accepted: 09/18/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND Local impedance (LI) has emerged as a new technology that informs on electrical catheter-tissue coupling during radiofrequency (RF) ablation. Recently, IntellaNav StablePoint, a novel LI-enabled catheter that equips contact force (CF) sensing, has been introduced. Although StablePoint and its predecessor IntellaNav MiFi OI share the common technology that reports LI, distinct mechanics for LI sensing between the two products raise a concern that the LI-RF lesion formation relationship may differ. METHODS In an ex vivo swine cardiac tissue model, we investigated the initial level and range of a reduction in LI during a 60-s RF ablation and the resultant lesion characteristics at nine combinations of three energy power (30, 40, and 50 W) and CF (10, 30, and 50 g) steps. Correlations and interactions between CF, LI, wattage, and formed lesions were analyzed. Incidence of achieving LI drop plateau and that of a steam pop were also determined. RESULTS Positive correlations existed between CF and initial LI, CF and absolute/relative LI drop, CF and lesion volume, and LI drop and lesion volume. At the same LI drop, wattage-dependent gain in lesion volume was observed. Steam pops occurred in all CF steps and the prevalence was highest at 50 W. LI drop predicted a steam pop with a cutoff value at 89Ω. CONCLUSION In StablePoint, wattage crucially affects LI drop and lesion volume. Because 30 W ablation may by underpowered for intramural lesion formation and 50 W often resulted in a steam pop, 40 W appears to achieve the balance between the safety and efficacy.
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Affiliation(s)
- Kenta Tsutsui
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Daisuke Kawano
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Hitoshi Mori
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan.,Department of Pediatric Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Ritsushi Kato
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Yoshifumi Ikeda
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Naokata Sumitomo
- Department of Pediatric Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Hidehira Fukaya
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Sagamihara, Japan
| | - Shiro Iwanaga
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Shintaro Nakano
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Toshihiro Muramatsu
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Kazuo Matsumoto
- Department of Cardiology, Saitama Medical University International Medical Center, Hidaka, Japan
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35
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Das M, Luik A, Shepherd E, Sulkin M, Laughner J, Oesterlein T, Duffy E, Meyer C, Jais P, Duchateau J, Yue A, Ullah W, Ramos P, García-Bolao I. Local catheter impedance drop during pulmonary vein isolation predicts acute conduction block in patients with paroxysmal atrial fibrillation: initial results of the LOCALIZE clinical trial. Europace 2021; 23:1042-1051. [PMID: 33550380 PMCID: PMC8286855 DOI: 10.1093/europace/euab004] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 01/06/2021] [Indexed: 11/28/2022] Open
Abstract
Aims Radiofrequency ablation creates irreversible cardiac damage through resistive heating and this temperature change results in a generator impedance drop. Evaluation of a novel local impedance (LI) technology measured exclusively at the tip of the ablation catheter found that larger LI drops were indicative of more effective lesion formation. We aimed to evaluate whether LI drop is associated with conduction block in patients with paroxysmal atrial fibrillation (AF) undergoing pulmonary vein isolation (PVI). Methods and results Sixty patients underwent LI-blinded de novo PVI using a point-by-point ablation workflow. Pulmonary vein rings were divided into 16 anatomical segments. After a 20-min waiting period, gaps were identified on electroanatomic maps. Median LI drop within segments with inter-lesion distance ≤6 mm was calculated offline. The diagnostic accuracy of LI drop for predicting segment block was assessed using receiver operating characteristic analysis. For segments with inter-lesion distance ≤6 mm, acutely blocked segments had a significantly larger LI drop [19.8 (14.1–27.1) Ω] compared with segments with gaps [10.6 (7.8–14.7) Ω, P < 0.001). In view of left atrial wall thickness differences, the association between LI drop and block was further evaluated for anterior/roof and posterior/inferior segments. The optimal LI cut-off value for anterior/roof segments was 16.1 Ω (positive predictive value for block: 96.3%) and for posterior/inferior segments was 12.3 Ω (positive predictive value for block: 98.1%) where inter-lesion distances were ≤6 mm. Conclusion The magnitude of LI drop was predictive of acute PVI segment conduction block in patients with paroxysmal AF. The thinner posterior wall required smaller LI drops for block compared with the thicker anterior wall.
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Affiliation(s)
- Moloy Das
- Department of Cardiology, Freeman Road Hospital, Newcastle upon Tyne, NE7 7DN, UK
| | - Armin Luik
- Medizinische Klinik IV, Städtisches Klinikum Karlsruhe, Academic Teaching Hospital of the University of Freiburg, Karlsruhe, Germany
| | - Ewen Shepherd
- Department of Cardiology, Freeman Road Hospital, Newcastle upon Tyne, NE7 7DN, UK
| | - Matthew Sulkin
- Boston Scientific Corp., Electrophysiology Department, St. Paul, MN, USA
| | - Jacob Laughner
- Boston Scientific Corp., Electrophysiology Department, St. Paul, MN, USA
| | - Tobias Oesterlein
- Boston Scientific Corp., Electrophysiology Department, St. Paul, MN, USA
| | - Elizabeth Duffy
- Boston Scientific Corp., Electrophysiology Department, St. Paul, MN, USA
| | - Christian Meyer
- Department of Cardiology, University Heart Center, University Hospital Hamburg, Hamburg, Germany
| | - Pierre Jais
- L'Institut de Rythmologie et Modélisation Cardiaque (LIRYC), Hôpital Cardiologique du Haut-Lévèque, CHU Bordeaux, Université de Bordeaux, Bordeaux, France
| | - Josselin Duchateau
- L'Institut de Rythmologie et Modélisation Cardiaque (LIRYC), Hôpital Cardiologique du Haut-Lévèque, CHU Bordeaux, Université de Bordeaux, Bordeaux, France
| | - Arthur Yue
- Department of Cardiology, University Hospital Southampton, Southampton, UK
| | - Waqas Ullah
- Department of Cardiology, University Hospital Southampton, Southampton, UK
| | - Pablo Ramos
- Department of Cardiology and Cardiovascular Surgery, Clìnica Universidad de Navarra, Pamplona, Spain.,IdiSNA, Navarra Institute for Health Research, Navarra, Spain
| | - Ignacio García-Bolao
- Department of Cardiology and Cardiovascular Surgery, Clìnica Universidad de Navarra, Pamplona, Spain.,IdiSNA, Navarra Institute for Health Research, Navarra, Spain
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Osei K, Sulkin MS, Hamann JJ, Hughes C, Shuros A, Nagy T, Kapa S, Meyers J. Local impedance-guided radiofrequency ablation with standard and high power: Results of a preclinical investigation. J Cardiovasc Electrophysiol 2021; 32:2060-2068. [PMID: 34223691 DOI: 10.1111/jce.15135] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/16/2021] [Accepted: 05/25/2021] [Indexed: 12/01/2022]
Abstract
BACKGROUND Local impedance (LI) drop measured with microfidelity electrodes embedded in the tip of an ablation catheter accurately reflects tissue heating during radiofrequency (RF) ablation. Previous studies found 15-30 Ω LI drops created successful lesions, while more than 40 Ω drops were associated with steam pops. The objective of this study was to evaluate the safety and efficacy of LI-guided ablation using standard (30 W) and high-power (50 W) in a preclinical model. METHODS RF lesions were created in explanted swine hearts (n = 6) to assess the feasibility of LI-guided ablation by targeting 10, 20, or 30 Ω (n = 20/group) drops. Subsequently, LI-guided ablation was evaluated in a chronic animal model (n = 8 Canines, 25-29 kg, 30/50 W). During the index procedure point-by-point intercaval line ablation and left inferior pulmonary vein (PV) isolation were performed. RF duration was at the operators' discretion but discontinued early if a 15-30 Ω drop was achieved. Operators attempted to avoid LI drops of more than 40 Ω. At 1-month, durable conduction block was evaluated with electroanatomic mapping followed by necropsy and histopathology. RESULTS In explanted tissue, terminating ablation at 10, 20, or 30 Ω LI drops created statistically larger lesions (p < .05; 1.8 [1.6-2.4] mm, 3.3 [3.0-3.7] mm; 4.9 [4.3-5.5] mm). LI-guided high-power ablation in vivo significantly reduced RF duration per application compared to standard-power (p < .05; intercaval: 8.9 ± 5.2 vs. 18.1 ± 11.0 s, PV: 9.6 ± 5.4 vs. 23.2 ± 10.3 s). LI drops of 15-40 Ω were more readily achievable for high-power (90.1%, 318/353) than standard-power (71.7%, 243/339). All intercaval lines and PV isolations were durable (16/16) at 1-month. Necropsy revealed no major collateral injury to the pericardium, phrenic nerve, esophagus, or lungs. There was no pericardial effusion, stroke, tamponade, or PV stenosis. Vagal nerve injury was found in two 30 W animals after using 19.7 ± 13.9 and 19.5 ± 11.8 s RF applications. CONCLUSION LI-guided ablation was found to be safe and efficacious in a chronic animal model. High-power ablation more readily achieved more than 15 Ω drops, reduced RF duration compared with standard-power, and had no major RF collateral injury.
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Affiliation(s)
- Kofi Osei
- Iowa Heart Center, West Des Moines, Iowa, USA
| | | | | | | | - Allan Shuros
- Boston Scientific Corp., Saint Paul, Minnesota, USA
| | - Tamas Nagy
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Suraj Kapa
- Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
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Nakamura K, Sasaki T, Minami K, Take Y, Inoue M, Sasaki W, Kishi S, Yoshimura S, Okazaki Y, Motoda H, Niijima K, Miki Y, Goto K, Kaseno K, Yamashita E, Koyama K, Funabashi N, Naito S. Prevalence, characteristics, and predictors of endocardial and nonendocardial conduction gaps during local impedance-guided extensive pulmonary vein isolation of atrial fibrillation with high-resolution mapping. J Cardiovasc Electrophysiol 2021; 32:2045-2059. [PMID: 34254714 DOI: 10.1111/jce.15152] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/12/2021] [Accepted: 06/07/2021] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Local impedance (LI) drops during radiofrequency ablation can predict lesion formation. Some conduction gaps during pulmonary vein isolation (PVI) can be associated with nonendocardial connections. This study aimed to investigate the incidence, characteristics, and predictors of endocardial and nonendocardial conduction gaps during an LI-guided PVI. METHODS AND RESULTS We prospectively enrolled 157 consecutive patients undergoing an initial LI-guided extensive PVI of atrial fibrillation (AF). After the first-pass encirclement, the residual conduction gaps and reconnected gaps were mapped using Rhythmia (Boston Scientific) and a mini-basket catheter. Right and left PV (RPV/LPV) gaps were observed in 22.3% and 18.5% of the patients, respectively: 27 endocardial and 49 nonendocardial gaps. The carina regions were common sites for the gaps (51 carina-related vs. 25 noncarina-related). The carina-related gaps consisted of more nonendocardial gaps than endocardial gaps (RPVs: 90.0% vs. 10.0%, p = .001; LPVs: 76.2% vs. 23.8%, p < .001). A univariate analysis revealed that paroxysmal AF and the left atrial (LA) volume index for RPV endocardial gaps (odds ratio [OR]: 8.640 and 0.946; p = .043 and 0.009), minor right inferior PV diameter for RPV nonendocardial gaps (OR: 1.165; p = .028), and major left inferior PV diameter for LPV endocardial gaps (OR: 1.233; p = .028) were significant predictors. CONCLUSIONS During the LI-guided PVI, approximately two-thirds of the conduction gaps were nonendocardial. The carina regions had more conduction gaps than noncarina regions, which was due to the presence of nonendocardial connections. Paroxysmal AF, a lower LA volume index, and larger inferior PV diameters may increase the risk of conduction gaps.
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Affiliation(s)
- Kohki Nakamura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Takehito Sasaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Kentaro Minami
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Yutaka Take
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Mitsuho Inoue
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Wataru Sasaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Shohei Kishi
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Shingo Yoshimura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Yoshinori Okazaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Hiroyuki Motoda
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Katsura Niijima
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Yuko Miki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Koji Goto
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Kenichi Kaseno
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Eiji Yamashita
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Keiko Koyama
- Division of Radiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
| | - Nobusada Funabashi
- Department of Cardiovascular Science and Medicine, Chiba University Graduate School of Medicine, Chiba City, Chiba, Japan
| | - Shigeto Naito
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan
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Kawano D, Mori H, Kato R, Tsutsui K, Ikeda Y, Sumitomo N, Fukaya H, Iwagana S, Nakano S, Muramatsu T, Matsumoto K. The optimal ablation setting for a local impedance guided catheter in an in vitro experimental model. J Cardiovasc Electrophysiol 2021; 32:2069-2076. [PMID: 34185348 DOI: 10.1111/jce.15136] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 05/20/2021] [Accepted: 06/07/2021] [Indexed: 01/09/2023]
Abstract
BACKGROUND The local impedance (LI) reflects the electrical catheter-tissue coupling and correlates with the local tissue temperature. However, there have been few clinical studies showing the recommended method for LI monitoring catheters. This study aimed to investigate the optimal ablation setting for this catheter in an in vitro experimental model. METHODS LI monitoring catheters were used in an excised swine heart experimental model. The tissue contact force (CF) was directly monitored from an external weight scale. Radiofrequency ablation was performed with a combination of various energy power settings (30, 40, and 50 W), and various CFs (10, 30, and 50 g) for 60 s. The correlation between the LI-related indexes, power, and CF with the lesion formation was statistically analyzed. RESULTS A positive correlation between the LI or lesion formation and CF was observed under all powers. Although the LI drop always correlated with the maximum lesion depth, lesion diameter, and lesion volume, the coefficient of the correlation value was lower under a high CF (lesion depth, diameter, and volume; 10 g, r = 0.8064, r = 0.8389, r = 0.8477; 30 g, r = 0.7590, r = 0.8063, r = 0.8060; 50 g r = 0.5555, r = 0.5701, and r = 0.5678, respectively). Steam pops occurred only under a 50 W ablation and the LI drop cutoff value for steam pops was 46 Ω. CONCLUSION The same LI drop did not always lead to the same lesion size when the CF differed. Monitoring the LI and not exceeding 46 Ω would be useful for a safe ablation.
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Affiliation(s)
- Daisuke Kawano
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Hitoshi Mori
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan.,Department of Pediatric Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Ritsushi Kato
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Kenta Tsutsui
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Yoshifumi Ikeda
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Naokata Sumitomo
- Department of Pediatric Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Hidehira Fukaya
- Department of Cardiovascular Medicine, Kitasato University School of Medicine, Tokyo, Japan
| | - Shiro Iwagana
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Shintaro Nakano
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Toshihiro Muramatsu
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Kazuo Matsumoto
- Department of Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
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Takigawa M, Goya M, Iwakawa H, Martin CA, Anzai T, Takahashi K, Kamata T, Matsumura Y, Amemiya M, Yamamoto T, Hirao T, Sekigawa M, Shirai Y, Tao S, Takahashi Y, Sasano T. Impact of a formula combining local impedance and conventional parameters on lesion size prediction. J Interv Card Electrophysiol 2021; 63:389-398. [PMID: 34156611 DOI: 10.1007/s10840-021-01013-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 05/23/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Although ablation energy (AE) and force-time integral (FTI) are well-known active predictors of lesion characteristics, these parameters do not reflect passive tissue reactions during ablation, which may instead be represented by drops in local impedance (LI). This study aimed to investigate if additional LI data improves predicting lesion characteristics and steam pops. METHODS RF applications at a range of powers (30 W, 40 W, and 50 W), contact forces (8 g, 15 g, 25 g, and 35 g), and durations (10-180 s) using perpendicular/parallel catheter orientations were performed in excised porcine hearts (N = 30). The correlation between AE, FTI, and lesion characteristics was examined, and the impact of LI (%LI drop (%LID) defined by the ΔLI divided by the initial LI) was additionally assessed. RESULTS Three hundred seventy-five lesions without steam pops were examined. Ablation energy (W × s) and FTI (g × s) showed a positive correlation with lesion depth (ρ = 0.824:P < 0.0001 and ρ = 0.708:P < 0.0001), surface area (ρ = 0.507:P < 0.0001 and ρ = 0.562:P < 0.0001), and volume (ρ = 0.807:P < 0.0001 and ρ = 0.685:P < 0.0001). %LID also showed a positive correlation individually with lesion depth (ρ = 0.643:P < 0.0001), surface area (ρ = 0.547:P < 0.0001), and volume (ρ = 0.733:P < 0.0001). However, the combined indices of AE × %LID (AE multiplied by %LID) and FTI × %LID (FTI multiplied by %LID) provided significantly stronger correlation with lesion depth (ρ = 0.834:P < 0.0001 and ρ = 0.809:P < 0.0001), surface area (ρ = 0.529:P < 0.0001 and ρ = 0.656:P < 0.0001), and volume (ρ = 0.864:P < 0.0001 and ρ = 0.838:P < 0.0001). This tendency was observed regardless of the catheter placement (parallel/perpendicular). AE (P = 0.02) and %LID (P = 0.002) independently remained as significant predictors to predict steam pops (N = 27). However, the AE × %LID did not increase the predictive power of steam pops compared to the AE alone. CONCLUSION LI, when combined with conventional parameters (AE and FTI), may provide stronger correlation with lesion characteristics.
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Affiliation(s)
- Masateru Takigawa
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan.
- Department of Advanced Arrhythmia Research, Tokyo Medical and Dental University, Tokyo, Japan.
| | - Masahiko Goya
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Hidehiro Iwakawa
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
- Department of Cardiovascular Medicine, Graduate School of Medicine, Akita University, Akita, Japan
| | | | - Tatsuhiko Anzai
- Department of Biostatistics M&D Data Science Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kunihiko Takahashi
- Department of Biostatistics M&D Data Science Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tatsuaki Kamata
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Yu Matsumura
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Miki Amemiya
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Tasuku Yamamoto
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Tatsuhiko Hirao
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Masahiro Sekigawa
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Yasuhiro Shirai
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Susumu Tao
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Yoshihide Takahashi
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
- Department of Advanced Arrhythmia Research, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tetsuo Sasano
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
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40
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Hashimoto K, Tsuzuki I, Seki Y, Ibe S, Yamashita T, Miyama H, Fujisawa T, Katsumata Y, Kimura T, Fukuda K, Takatsuki S. Change in the local impedance and electrograms recorded by a micro-electrode tip catheter during initial atrial fibrillation ablation. J Arrhythm 2021; 37:566-573. [PMID: 34141009 PMCID: PMC8207389 DOI: 10.1002/joa3.12535] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 03/04/2021] [Accepted: 03/18/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND A novel measurement of the local impedance (LI) and electrograms recorded from micro-electrodes on catheter tip has been developed. However, the data during pulmonary vein (PV) ablation is not sufficient. We aimed to investigate the utility of this measurement during initial atrial fibrillation (AF) ablation. METHODS We investigated 111 representative radiofrequency applications in 7 AF patients without a history of prior ablation (6 males, age 68 [65-72] years, 2 persistent AF). The ablation strategy was PV isolation for paroxysmal AF and single ring box isolation for persistent AF, using MiFi catheter. The correlation of the generator impedance (GI) drop and LI drop after radiofrequency applications and the predictive value of the initial LI elevation before radiofrequency applications for LI drop were analyzed. Also, the LI and GI drop were investigated according to the location of RF applications. RESULTS The LI drop was higher than GI drop (23.7 [16.4-35.7] and 9.0 [6.0-12.0]; P < .01). There were correlations between the initial LI elevation and LI drop (R 2 = 0.466, P < .01) and between the LI and GI drop (R 2 = 0.263, P < .01). The LI drops significantly differed according to the different anatomical localizations by the Kruskal-Wallis test, although the GI drops did not differ (P < .01 and P = .49, respectively). CONCLUSION LI drop was associated with initial LI elevation and was larger than GI drop. LI drop was different according to locations, although GI drop was not. These findings might indicate that LI drop would be a more sensitive marker for lesion formation than GI drop.
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Affiliation(s)
- Kenji Hashimoto
- Department of CardiologyKeio University School of MedicineTokyoJapan
| | - Ippei Tsuzuki
- Department of CardiologyKeio University School of MedicineTokyoJapan
| | - Yuta Seki
- Department of CardiologyKeio University School of MedicineTokyoJapan
| | - Susumu Ibe
- Department of CardiologyKeio University School of MedicineTokyoJapan
| | | | - Hiroshi Miyama
- Department of CardiologyKeio University School of MedicineTokyoJapan
| | - Taishi Fujisawa
- Department of CardiologyKeio University School of MedicineTokyoJapan
| | | | - Takehiro Kimura
- Department of CardiologyKeio University School of MedicineTokyoJapan
| | - Keiichi Fukuda
- Department of CardiologyKeio University School of MedicineTokyoJapan
| | - Seiji Takatsuki
- Department of CardiologyKeio University School of MedicineTokyoJapan
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41
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Sohns C, Marrouche NF. Atrial fibrillation and cardiac fibrosis. Eur Heart J 2021; 41:1123-1131. [PMID: 31713590 DOI: 10.1093/eurheartj/ehz786] [Citation(s) in RCA: 126] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 09/30/2019] [Accepted: 10/23/2019] [Indexed: 12/25/2022] Open
Abstract
The understanding of atrial fibrillation (AF) evolved from a sole rhythm disturbance towards the complex concept of a cardiomyopathy based on arrhythmia substrates. There is evidence that atrial fibrosis can be visualized using late gadolinium enhancement cardiac magnetic resonance imaging and that it is a powerful predictor for the outcome of AF interventions. However, a strategy of an individual and fibrosis guided management of AF looks promising but results from prospective multicentre trials are pending. This review gives an overview about the relationship between cardiac fibrosis and AF focusing on translational aspects, clinical observations, and fibrosis imaging to emphasize the concept of personalized paths in AF management taking into account the individual amount and distribution of fibrosis.
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Affiliation(s)
- Christian Sohns
- Clinic for Electrophysiology, Herz- und Diabeteszentrum NRW, Ruhr-Universität Bochum, Bad Oeynhausen, Germany
| | - Nassir F Marrouche
- Cardiac Electrophysiology, Tulane University School of Medicine, 1430 Tulane Avenue, Box 8548, New Orleans, LA 70112, USA
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42
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Chu GS, Gupta D. Local impedance to guide focal radiofrequency ablation: There is life in the old dog yet. J Cardiovasc Electrophysiol 2021; 32:1549-1552. [PMID: 33851472 DOI: 10.1111/jce.15039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 04/11/2021] [Indexed: 01/06/2023]
Affiliation(s)
- Gavin S Chu
- Department of Cardiology, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK
| | - Dhiraj Gupta
- Department of Cardiology, Liverpool Heart and Chest Hospital NHS Foundation Trust, Liverpool, UK.,Department of Cardiology, Liverpool Center for Cardiovascular Science, University of Liverpool, Liverpool, UK
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Gaeta S, Bahnson TD, Henriquez C. High-Resolution Measurement of Local Activation Time Differences From Bipolar Electrogram Amplitude. Front Physiol 2021; 12:653645. [PMID: 33967825 PMCID: PMC8100452 DOI: 10.3389/fphys.2021.653645] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 03/30/2021] [Indexed: 11/13/2022] Open
Abstract
Localized changes in myocardial conduction velocity (CV) are pro-arrhythmic, but high-resolution mapping of local CV is not yet possible during clinical electrophysiology procedures. This is in part because measurement of local CV at small spatial scales (1 mm) requires accurate annotation of local activation time (LAT) differences with very high temporal resolution (≤1 ms), beyond that of standard clinical methods. We sought to develop a method for high-resolution measurement of LAT differences and validate against existing techniques. First, we use a simplified theoretical model to identify a quantitative relationship between the LAT difference of a pair of electrodes and the peak amplitude of the bipolar EGM measured between them. This allows LAT differences to be calculated from bipolar EGM peak amplitude, by a novel "Determination of EGM Latencies by Transformation of Amplitude" (DELTA) method. Next, we use simulated EGMs from a computational model to validate this method. With 1 kHz sampling, LAT differences less than 4 ms were more accurately measured with DELTA than by standard LAT annotation (mean error 3.8% vs. 22.9%). In a 1-dimensional and a 2-dimension model, CV calculations were more accurate using LAT differences found by the DELTA method than by standard LAT annotation (by unipolar dV/dt timing). DELTA-derived LAT differences were more accurate than standard LAT annotation in simulated complex fractionated EGMs from a model incorporating fibrosis. Finally, we validated the DELTA method in vivo using 18,740 bipolar EGMs recorded from the left atrium of 10 atrial fibrillation patients undergoing catheter ablation. Using clinical EGMs, there was agreement in LAT differences found by DELTA, standard LAT annotation, and unipolar waveform cross-correlation. These results demonstrate an underlying relationship between a bipolar EGM's peak amplitude and the activation time difference between its two electrodes. Our computational modeling and clinical results suggest this relationship can be leveraged clinically to improve measurement accuracy for small LAT differences, which may improve CV measurement at small spatial scales.
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Affiliation(s)
- Stephen Gaeta
- Inova Heart and Vascular Institute, Falls Church, VA, United States.,Division of Cardiology, Duke University Medical Center, Durham, NC, United States
| | - Tristram D Bahnson
- Division of Cardiology, Duke University Medical Center, Durham, NC, United States
| | - Craig Henriquez
- Department of Biomedical Engineering, Duke University, Durham, NC, United States
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Miyazaki S, Hasegawa K, Mukai M, Aoyama D, Nodera M, Yamaguchi J, Shiomi Y, Tama N, Ikeda H, Ishida K, Uzui H, Tada H. Superior vena cava isolation using a novel ablation catheter incorporating local impedance monitoring. J Interv Card Electrophysiol 2021; 64:291-300. [PMID: 33755817 DOI: 10.1007/s10840-021-00980-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 03/15/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND A novel technology able to measure the local impedance (LI) during radiofrequency ablation has become available for clinical use. We investigated the change in the LI characteristics during superior vena cava isolations (SVCIs) using a novel catheter equipped with mini-electrodes. METHODS Twenty paroxysmal atrial fibrillation patients (68 ± 9 years; 14 males) underwent an SVCI by targeting breakthroughs. Subsequently, dormant conduction provoked by adenosine triphosphate (ATP) was evaluated. RESULTS Electrical SVCIs were successfully achieved in all with 7.2 ± 3.0 radiofrequency applications (RFA) without any complications. The procedure and fluoroscopic times were 13.1 ± 8.1 and 2.8 ± 2.3 min. No ablation was required at the anteroseptal SVC in 19 (95.0%) patients. The baseline LI and generator impedance (GI) were 125 ± 23 and 105 ± 14Ω. LI drops during RFA were significantly greater than GI drops (17 ± 12 vs. 4 ± 4Ω, p < 0.001). The correlation between the LI drops and GI drops was relatively high (R = 0.69, p < 0.001). LI drops were highest at the septal SVC and lowest at the lateral followed by antero-lateral SVC. The baseline electrogram amplitude between the mini-electrodes and tip-ring electrodes was 1.2 ± 1.4 and 0.8 ± 0.6 mV. The mini-electrode amplitude is more sharply attenuated with a greater magnitude than the tip-ring amplitude (p < 0.001). ATP-provoked dormant conduction was exposed in 10/17 (58.8%) patients and antero-lateral SVC gap locations in 7. Antero-lateral SVC LI drops were similar between patients with and without dormancy. CONCLUSIONS The LI drop magnitude during RFA significantly differed among the SVC segments. Antero-lateral SVC ATP-provoked dormant conduction was often exposed, and additional applications are recommended following the isolation for a robust SVCI.
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Affiliation(s)
- Shinsuke Miyazaki
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan.
| | - Kanae Hasegawa
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Moe Mukai
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Daisetsu Aoyama
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Minoru Nodera
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Junya Yamaguchi
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Yuichiro Shiomi
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Naoto Tama
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Hiroyuki Ikeda
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Kentaro Ishida
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Hiroyasu Uzui
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
| | - Hiroshi Tada
- Department of Cardiovascular Medicine, Faculty of Medical Sciences, University of Fukui, 23-3 Shimo-aiduki, Matsuoka, Eiheiji-cho, Yoshida-gun, Fukui, 910-1193, Japan
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Clinical implications of local impedance measurement using the IntellaNav MiFi OI ablation catheter: an ex vivo study. J Interv Card Electrophysiol 2021; 63:185-195. [DOI: 10.1007/s10840-021-00954-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 02/01/2021] [Indexed: 10/22/2022]
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A variant of pulmonary vein-gap reentrant atrial tachycardia with multiple epicardial conduction gaps. J Cardiol Cases 2020; 22:286-290. [DOI: 10.1016/j.jccase.2020.07.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 07/09/2020] [Accepted: 07/12/2020] [Indexed: 11/24/2022] Open
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Nakamura K, Sasaki T, Take Y, Minami K, Sasaki W, Kishi S, Yoshimura S, Okazaki Y, Miki Y, Goto K, Kaseno K, Yamashita E, Koyama K, Funabashi N, Naito S. Effect of preventing air intrusion on silent strokes during atrial fibrillation ablation using a mini-basket catheter. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2020; 44:71-81. [PMID: 33216388 DOI: 10.1111/pace.14131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 11/04/2020] [Accepted: 11/15/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND Air bubble intrusion through transseptal sheaths during left atrial (LA) catheter ablation can cause cerebral embolisms, especially when using complex-shape catheters. This study aimed to compare the incidence of silent cerebral events (SCEs) after atrial fibrillation (AF) catheter ablation using a mini-basket catheter (IntellaMap Orion; Boston Scientific) between the following groups: group SP, strict prevention of LA air intrusion and group CP, conventional air intrusion prevention. METHODS We enrolled 123 consecutive AF patients (group SP, n = 61 and group CP, n = 62) who underwent brain magnetic resonance imaging after a local-impedance-guided ablation using one mini-basket catheter and one circular mapping catheter. The preventive strategy in group SP included (a) the insertion of the mini-basket catheter into the transseptal sheaths in a container filled with heparinized saline and (b) no exchange of all catheters over the sheaths. RESULTS SCEs were detected in 67 patients (54.5%), and the incidence of SCEs did not significantly differ between groups SP and CP (55.7% vs 53.2%; P = .780). A multivariate analysis demonstrated that an older age, non-paroxysmal AF, and radiofrequency (RF) power output were independent positive predictors of SCEs (odds ratios: 1.079, 5.613, and 1.405; P = .005, <.001, and .012). On the follow-up MR imaging, 83.5% of the SCEs in group SP and 87.7% in group CP disappeared (P = .398). CONCLUSIONS Strict prevention of LA air intrusion may have no additional effect for reducing the incidence of SCEs after local impedance-guided AF ablation using a mini-basket catheter. An older age, non-paroxysmal AF, and high-power RF applications may increase the risk of SCEs.
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Affiliation(s)
- Kohki Nakamura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Takehito Sasaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Yutaka Take
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Kentaro Minami
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Wataru Sasaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Shohei Kishi
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Shingo Yoshimura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Yoshinori Okazaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Yuko Miki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Koji Goto
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Kenichi Kaseno
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Eiji Yamashita
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Keiko Koyama
- Division of Radiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
| | - Nobusada Funabashi
- Department of Cardiovascular Science and Medicine, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Shigeto Naito
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi, Japan
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Nakamura K, Sasaki T, Take Y, Minami K, Inoue M, Asahina C, Sasaki W, Kishi S, Yoshimura S, Okazaki Y, Motoda H, Niijima K, Miki Y, Goto K, Kaseno K, Yamashita E, Koyama K, Funabashi N, Naito S. Incidence and characteristics of silent cerebral embolisms after radiofrequency-based atrial fibrillation ablation: A propensity score-matched analysis between different mapping catheters and indices for guiding ablation. J Cardiovasc Electrophysiol 2020; 32:16-26. [PMID: 33141496 DOI: 10.1111/jce.14800] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 08/24/2020] [Accepted: 09/22/2020] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The difference in the incidence and characteristics of silent cerebral events (SCEs) after radiofrequency-based atrial fibrillation (AF) ablation between the different mapping catheters and indices used for guiding radiofrequency ablation remains unclear. This study aimed to compare the incidence and characteristics of postablation SCEs between the following two groups: Group C, Ablation Index-guided ablation using two circular mapping catheters with CARTO (Biosense Webster); Group R, local impedance-guided ablation using one mini-basket catheter and one circular mapping with Rhythmia (Boston Scientific). METHODS AND RESULTS Of 211 consecutive patients who underwent an AF ablation and brain magnetic resonance (MR) imaging after the ablation, 120 patients (each group, n = 60) were selected by propensity score matching. SCEs were detected in 37 patients (30.8%). Group R had a higher incidence of SCEs (51.7% vs. 10.0%; p < .001) and more SCEs per patient (median, 3 vs. 1, p = .028) than Group C. A multivariate analysis demonstrated that nonparoxysmal AF and being Group R were independent positive predictors of SCEs (odds ratios, 6.930 and 15.464; both p < .001). On the follow-up MR imaging, all SCEs in Group C and 87.9% of the SCEs in Group R disappeared (p = .537). CONCLUSIONS Group R had a significantly higher incidence of SCEs than Group C. Most probably the use of a complexly designed basket mapping catheter is the reason for the difference in the incidence of SCEs but further validation is needed. A nonparoxysmal form of AF may also increase the risk of SCEs during these ablation procedures.
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Affiliation(s)
- Kohki Nakamura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Takehito Sasaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Yutaka Take
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Kentaro Minami
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Mitsuho Inoue
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Chisa Asahina
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Wataru Sasaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Shohei Kishi
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Shingo Yoshimura
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Yoshinori Okazaki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Hiroyuki Motoda
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Katsura Niijima
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Yuko Miki
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Koji Goto
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Kenichi Kaseno
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Eiji Yamashita
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Keiko Koyama
- Division of Radiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
| | - Nobusada Funabashi
- Department of Cardiovascular Science and Medicine, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Shigeto Naito
- Division of Cardiology, Gunma Prefectural Cardiovascular Center, Gunma, Japan
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Laţcu DG, Bun SS, Casado Arroyo R, Wedn AM, Benaich FA, Hasni K, Enache B, Saoudi N. Scar identification, quantification, and characterization in complex atrial tachycardia: a path to targeted ablation? Europace 2020; 21:i21-i26. [PMID: 30801130 DOI: 10.1093/europace/euy182] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 07/23/2018] [Indexed: 01/21/2023] Open
Abstract
Successful catheter ablation of scar-related atrial tachycardia depends on correct identification of the critical isthmus. Often, this is a represented by a small bundle of viable conducting tissue within a low-voltage area. It's identification depends on the magnitude of the signal/noise ratio. Ultra-high density mapping, multipolar catheters with small (eventually unidirectional) and closely-spaced electrodes improves low-voltage electrogram detection. Background noise limitation is also of major importance for improving the signal/noise ratio. Electrophysiological properties of the critical isthmus and the characteristics of the local bipolar electrograms have been recently demonstrated as hallmarks of successful ablation sites in the setting of scar-related atrial tachycardia.
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Affiliation(s)
| | - Sok-Sithikun Bun
- Service de Cardiologie, Centre Hospitalier Princesse Grace, Avenue Pasteur, Monaco
| | - Ruben Casado Arroyo
- Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Ahmed Moustfa Wedn
- Service de Cardiologie, Centre Hospitalier Princesse Grace, Avenue Pasteur, Monaco
| | | | - Karim Hasni
- Service de Cardiologie, Centre Hospitalier Princesse Grace, Avenue Pasteur, Monaco
| | - Bogdan Enache
- Service de Cardiologie, Centre Hospitalier Princesse Grace, Avenue Pasteur, Monaco
| | - Nadir Saoudi
- Service de Cardiologie, Centre Hospitalier Princesse Grace, Avenue Pasteur, Monaco
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