title: Contrast-enhanced MRI-derived scar patterns and associated ventricular tachycardias in nonischemic cardiomyopathy: implications for the ablation strategy.
abstract: BACKGROUND
  There are limited data on typical arrhythmogenic substrates and associated ventricular tachycardias (VT) in patients with nonischemic cardiomyopathy. The substrate location may have implications for the ablation strategy.
  
  
  RESULTS
  Nineteen consecutive patients with nonischemic cardiomyopathy (age 58±14 years, 79% men, left ventricular ejection fraction 41±11%) who underwent contrast-enhanced MRI and VT ablation were included. On the basis of 3-dimensional contrast-enhanced MRI-derived scar reconstructions, 8 patients (42%) had predominant basal anteroseptal scar, 9 patients (47%) had predominant inferolateral scar, and 2 patients (11%) had other scar types. Three distinct VT morphologies (≥1 of 3 inducible in 16/19 patients) were associated with underlying scar type. In 9 patients with anteroseptal scar-related VT (8/9 predominant scar, 1/9 nonpredominant), ablation target sites (defined as sites with ≥11/12 pacemap, concealed entrainment or VT termination during ablation) were located in the aortic root and/or anteroseptal left ventricular endocardium in 8 patients (89%) and in the anterior cardiac vein in 1 patient (11%), with additional target sites at the right ventricular septum in 2 patients (22%) and at the epicardium in 1 patient (11%). In contrast, in 8 patients with predominant inferolateral scar-related VT, target sites were located at the epicardium in 5 patients (63%) and in the endocardial inferolateral left ventricle in 3 patients (37%).
  
  
  CONCLUSIONS
  Two typical scar patterns (anteroseptal and inferolateral) account for 89% of arrhythmogenic substrates in patients with nonischemic cardiomyopathy. Three distinct VT morphologies are highly suggestive of the presence of these scars. Anteroseptal scars were, in general, most effectively approached from the aortic root or anteroseptal left ventricular endocardium, whereas inferolateral scars frequently required an epicardial approach.
authors.affiliation: Department of Cardiology, and Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Sebastiaan R D
authors.initials: SR
authors.lastname: Piers
authors.forename: Qian
authors.initials: Q
authors.lastname: Tao
authors.forename: Carine F B
authors.initials: CF
authors.lastname: van Huls van Taxis
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Schalij
authors.forename: Rob J
authors.initials: RJ
authors.lastname: van der Geest
authors.forename: Katja
authors.initials: K
authors.lastname: Zeppenfeld
mesh_terms: D055424:Cardiac-Gated Imaging Techniques; D009202:Cardiomyopathies / Q000503:physiopathology* / Q000601:surgery*; D017115:Catheter Ablation; D002921:Cicatrix / Q000503:physiopathology*; D003287:Contrast Media; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000503:physiopathology* / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA
keywords: catheter ablation; magnetic resonance imaging; tachycardia, ventricular