title: The association of left atrial low-voltage regions on electroanatomic mapping with low attenuation regions on cardiac computed tomography perfusion imaging in patients with atrial fibrillation.
abstract: BACKGROUND
  Previous studies have shown that contrast-enhanced multidetector computed tomography (CE-MDCT) could identify ventricular fibrosis after myocardial infarction. However, whether CE-MDCT can characterize atrial low-voltage regions remains unknown.
  
  
  OBJECTIVE
  The purpose of this study was to examine the association of CE-MDCT image attenuation with left atrial (LA) low bipolar voltage regions in patients undergoing repeat ablation for atrial fibrillation recurrence.
  
  
  METHODS
  We enrolled 20 patients undergoing repeat ablation for atrial fibrillation recurrence. All patients underwent preprocedural 3-dimensional CE-MDCT of the LA, followed by voltage mapping (>100 points) of the LA during the ablation procedure. Epicardial and endocardial contours were manually drawn around LA myocardium on multiplanar CE-MDCT axial images. Segmented 3-dimensional images of the LA myocardium were reconstructed. Electroanatomic map points were retrospectively registered to the corresponding CE-MDCT images.
  
  
  RESULTS
  A total of 2028 electroanatomic map points obtained in sinus rhythm from the LA endocardium were registered to the segmented LA wall CE-MDCT images. In a linear mixed model, each unit increase in the local image attenuation ratio was associated with 25.2% increase in log bipolar voltage (P = .046) after adjusting for age, sex, body mass index, and LA volume, as well as clustering of data by patient and LA regions.
  
  
  CONCLUSIONS
  We demonstrate that the image attenuation ratio derived from CE-MDCT is associated with LA bipolar voltage. The potential ability to image fibrosis via CE-MDCT may provide a useful alternative in patients with contraindications to magnetic resonance imaging.
authors.affiliation: Department of Cardiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China; Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Zhiyu
authors.initials: Z
authors.lastname: Ling
authors.affiliation: Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: John
authors.initials: J
authors.lastname: McManigle
authors.affiliation: Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
authors.forename: Vadim
authors.initials: V
authors.lastname: Zipunnikov
authors.affiliation: Biomedical Engineering.
authors.forename: Farhad
authors.initials: F
authors.lastname: Pashakhanloo
authors.affiliation: Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Irfan M
authors.initials: IM
authors.lastname: Khurram
authors.affiliation: Department of Radiology.
authors.forename: Stefan L
authors.initials: SL
authors.lastname: Zimmerman
authors.affiliation: Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Binu
authors.initials: B
authors.lastname: Philips
authors.affiliation: Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Marine
authors.affiliation: Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: David D
authors.initials: DD
authors.lastname: Spragg
authors.affiliation: Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ashikaga
authors.affiliation: Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Hugh
authors.initials: H
authors.lastname: Calkins
authors.affiliation: Department of Medicine/Cardiology, Johns Hopkins University, Baltimore, Maryland; Department of Epidemiology, Johns Hopkins University, Baltimore, Maryland. Electronic address: snazarian@jhmi.edu.
authors.forename: Saman
authors.initials: S
authors.lastname: Nazarian
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D016279:Atrial Function, Left; D018780:Body Surface Potential Mapping / Q000379:methods; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods; D005260:Female; D005355:Fibrosis; D006325:Heart Atria / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods; D055414:Myocardial Perfusion Imaging / Q000379:methods; D012008:Recurrence; D015203:Reproducibility of Results
keywords: Atrial fibrillation; Cardiac computed tomography perfusion imaging; Electroanatomic mapping