title: Repeat left atrial catheter ablation: cardiac magnetic resonance prediction of endocardial voltage and gaps in ablation lesion sets.
abstract: BACKGROUND
  Studies have reported an inverse relationship between late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) signal intensity and left atrial (LA) endocardial voltage after LA ablation. However, there is controversy regarding the reproducibility of atrial LGE CMR and its ability to identify gaps in ablation lesions. Using systematic and objective techniques, this study examines the correlation between atrial CMR and endocardial voltage.
  
  
  RESULTS
  Twenty patients who had previous ablation for atrial fibrillation and represented with paroxysmal atrial fibrillation or atrial tachycardia underwent preablation LGE CMR. During the ablation procedure, high-density point-by-point Carto voltage maps were acquired. Three-dimensional CMR reconstructions were registered with the Carto anatomies to allow comparison of voltage and LGE signal intensity. Signal intensities around the left and right pulmonary vein antra and along the LA roof and mitral lines on the CMR-segmented LA shells were extracted to examine differences between electrically isolated and reconnected lesions. There were a total of 6767 data points across the 20 patients. Only 119 (1.8%) of the points were ≤ 0.05 mV. There was only a weak inverse correlation between either unipolar (r = -0.18) or bipolar (r = -0.17) voltage and LGE CMR signal intensities with low voltage occurring across a large range of signal intensities. Signal intensities were not statistically different for electrically isolated and reconnected lesions.
  
  
  CONCLUSIONS
  This study demonstrates that there is only a weak point-by-point relationship between LGE CMR and endocardial voltage in patients undergoing repeat LA ablation. Using an objective method of assessing gaps in ablation lesions, LGE CMR is unable to reliably predict sites of electrical conduction.
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom. james.harrison@kcl.ac.uk.
authors.forename: James L
authors.initials: JL
authors.lastname: Harrison
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Christian
authors.initials: C
authors.lastname: Sohns
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Nick W
authors.initials: NW
authors.lastname: Linton
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Rashed
authors.initials: R
authors.lastname: Karim
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Williams
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Kawal S
authors.initials: KS
authors.lastname: Rhode
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Jaswinder
authors.initials: J
authors.lastname: Gill
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Michael
authors.initials: M
authors.lastname: Cooklin
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: C Aldo
authors.initials: CA
authors.lastname: Rinaldi
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Matthew
authors.initials: M
authors.lastname: Wright
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Tobias
authors.initials: T
authors.lastname: Schaeffter
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Reza S
authors.initials: RS
authors.lastname: Razavi
authors.affiliation: From the Division of Imaging Sciences & Biomedical Engineering, King's College London (J.L.H., C.S., N.W.L., R.K., S.E.W., K.S.R., J.G., C.A.R., M.W., T.S., R.S.R., M.D.O.), Department of Cardiology (J.L.H., N.W.L., S.E.W., J.G., M.C., C.A.R., M.W, M.D.O.), Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom.
authors.forename: Mark D
authors.initials: MD
authors.lastname: O'Neill
mesh_terms: D000200:Action Potentials; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects; D003287:Contrast Media; D004699:Endocardium / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006325:Heart Atria / Q000503:physiopathology / Q000601:surgery*; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds; D011237:Predictive Value of Tests; D012008:Recurrence; D012086:Reoperation; D013617:Tachycardia, Supraventricular / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol
keywords: atrial fibrillation; atrium; cardiac magnetic resonance imaging; catheter ablation; voltage