PMID- 30678791 OWN - NLM STAT- MEDLINE DCOM- 20200401 LR - 20200401 IS - 2405-5018 (Electronic) IS - 2405-500X (Print) IS - 2405-500X (Linking) VI - 5 IP - 1 DP - 2019 Jan TI - Ablation Lesion Characterization in Scarred Substrate Assessed Using Cardiac Magnetic Resonance. PG - 91-100 LID - S2405-500X(18)30879-X [pii] LID - 10.1016/j.jacep.2018.11.001 [doi] AB - OBJECTIVES: This study examined radiofrequency catheter ablation (RFCA) lesions within and around scar by cardiac magnetic resonance (CMR) imaging and histology. BACKGROUND: Substrate modification by RFCA is the cornerstone therapy for ventricular arrhythmias. RFCA in scarred myocardium, however, is not well understood. METHODS: We performed electroanatomic mapping and RFCA in the left ventricles of 8 swine with myocardial infarction. Non-contrast-enhanced T(1)-weighted (T1w) and contrast-enhanced CMR after RFCA were compared with gross pathology and histology. RESULTS: Of 59 lesions, 17 were in normal myocardium (voltage >1.5 mV), 21 in border zone (0.5 to 1.5 mV), and 21 in scar (<0.5 mV). All RFCA lesions were enhanced in T1w CMR, whereas scar was hypointense, allowing discrimination among normal myocardium, scar, and RFCA lesions. With contrast-enhancement, lesions and scar were similarly enhanced and not distinguishable. Lesion width and depth in T1w CMR correlated with necrosis in pathology (both; r(2) = 0.94, p < 0.001). CMR lesion volume was significantly different in normal myocardium, border zone, and scar (median: 397 [interquartile range (IQR): 301 to 474] mm(3), 121 [IQR: 87 to 201] mm(3), 66 [IQR: 33 to 123] mm(3), respectively). RFCA force-time integral, impedance, and voltage changes did not correlate with lesion volume in border zone or scar. Histology showed that ablation necrosis extended into fibrotic tissue in 26 lesions and beyond in 14 lesions. In 7 lesions, necrosis expansion was blocked and redirected by fat. CONCLUSIONS: T1w CMR can selectively enhance necrotic tissue in and around scar and may allow determination of the completeness of ablation intra- and post-procedure. Lesion formation in scar is affected by tissue characteristics, with fibrosis and fat acting as thermal insulators. CI - Copyright (c) 2019 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved. FAU - Tao, Susumu AU - Tao S AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland. Electronic address: stao5.1978@gmail.com. FAU - Guttman, Michael A AU - Guttman MA AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Fink, Sarah AU - Fink S AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Elahi, Hassan AU - Elahi H AD - Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Patil, Kaustubha D AU - Patil KD AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Ashikaga, Hiroshi AU - Ashikaga H AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Kolandaivelu, Aravindan D AU - Kolandaivelu AD AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Berger, Ronald D AU - Berger RD AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Halushka, Marc K AU - Halushka MK AD - Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Schmidt, Ehud J AU - Schmidt EJ AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Herzka, Daniel A AU - Herzka DA AD - Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland. FAU - Halperin, Henry R AU - Halperin HR AD - Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland. LA - eng GR - R01 EB022011/EB/NIBIB NIH HHS/United States GR - R01 HL094610/HL/NHLBI NIH HHS/United States GR - R21 EB023515/EB/NIBIB NIH HHS/United States PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20181226 PL - United States TA - JACC Clin Electrophysiol JT - JACC. Clinical electrophysiology JID - 101656995 SB - IM CIN - JACC Clin Electrophysiol. 2019 Jan;5(1):101-103. PMID: 30678773 MH - Animals MH - Arrhythmias, Cardiac/physiopathology/surgery MH - Cardiac Imaging Techniques/methods MH - *Catheter Ablation MH - *Cicatrix/diagnostic imaging/physiopathology MH - Electrophysiologic Techniques, Cardiac/*methods MH - *Heart Ventricles/diagnostic imaging/physiopathology MH - Magnetic Resonance Imaging/*methods MH - Myocardial Infarction/physiopathology/surgery MH - Swine PMC - PMC6355250 MID - NIHMS1511973 OTO - NOTNLM OT - cardiac magnetic resonance OT - myocardial infarction OT - non-contrast-enhanced T(1)-weighted imaging OT - radiofrequency catheter ablation OT - ventricular arrhythmia COIS- Disclosure: H.H.: Imricor - royalties No other authors have any potential conflict of interest to disclose. EDAT- 2019/01/27 06:00 MHDA- 2020/04/02 06:00 PMCR- 2020/01/01 CRDT- 2019/01/26 06:00 PHST- 2018/04/17 00:00 [received] PHST- 2018/10/30 00:00 [revised] PHST- 2018/11/01 00:00 [accepted] PHST- 2019/01/26 06:00 [entrez] PHST- 2019/01/27 06:00 [pubmed] PHST- 2020/04/02 06:00 [medline] PHST- 2020/01/01 00:00 [pmc-release] AID - S2405-500X(18)30879-X [pii] AID - 10.1016/j.jacep.2018.11.001 [doi] PST - ppublish SO - JACC Clin Electrophysiol. 2019 Jan;5(1):91-100. doi: 10.1016/j.jacep.2018.11.001. Epub 2018 Dec 26.