title: Electroanatomic characterization of post-infarct scars comparison with 3-dimensional myocardial scar reconstruction based on magnetic resonance imaging.
abstract: OBJECTIVE
  This study was designed to compare electroanatomic mapping (EAM) and magnetic resonance imaging (MRI) with delayed contrast enhancement (DCE) data for delineation of post-infarct scars.
  
  
  BACKGROUND
  Electroanatomic substrate mapping is an important step in the post-infarct ventricular tachycardia (VT) ablation strategy, but this technique has not yet been compared with a gold-standard noninvasive tool informing on the topography and transmural extent of myocardial scars in humans.
  
  
  METHODS
  Ten patients (9 men, age 71 +/- 10 years) admitted for post-infarct VT ablation underwent both a left ventricle DCE MRI and a sinus-rhythm 3-dimensional (3D) (CARTO) EAM (Biosense Webster, Johnson & Johnson, Diamond Bar, California). A 3D color-coded MRI-reconstructed left ventricular endocardial shell was generated to display scar data (intramural location and transmural extent). A matching process allocated any CARTO point to its corresponding position on the MRI map. Electrogram (EGM) characteristics were then evaluated in relation to scar data.
  
  
  RESULTS
  A spiky EGM morphology, a reduced unipolar or bipolar EGM voltage amplitude (<6.52 and <1.54 mV, respectively), as well as a longer bipolar EGM duration (>56 ms) independently correlated with the presence of scar whatever its intramural position. Endocardial scars had a larger degree of signal reduction than intramural or epicardial scars. None of the parameters was correlated with transmural scar depth. A clear mismatch in infarct surface between CARTO and MRI maps was observed in one-third of infarct zones.
  
  
  CONCLUSIONS
  Sinus-rhythm EAM helps identify the limits of post-infarct scars. However, the accuracy of EAM for precise scar delineation is limited. This limit might be circumvented using anatomical information provided by 3D MRI data.
authors.affiliation: Department of Cardiology, University Hospital Nancy, Nancy, France.
authors.forename: Andrei
authors.initials: A
authors.lastname: Codreanu
authors.forename: Freddy
authors.initials: F
authors.lastname: Odille
authors.forename: Etienne
authors.initials: E
authors.lastname: Aliot
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Marie
authors.forename: Isabelle
authors.initials: I
authors.lastname: Magnin-Poull
authors.forename: Marius
authors.initials: M
authors.lastname: Andronache
authors.forename: Damien
authors.initials: D
authors.lastname: Mandry
authors.forename: Wassila
authors.initials: W
authors.lastname: Djaballah
authors.forename: Denis
authors.initials: D
authors.lastname: Régent
authors.forename: Jacques
authors.initials: J
authors.lastname: Felblinger
authors.forename: Christian
authors.initials: C
authors.lastname: de Chillou