title: Integration of merged delayed-enhanced magnetic resonance imaging and multidetector computed tomography for the guidance of ventricular tachycardia ablation: a pilot study.
abstract: BACKGROUND
  Delayed enhancement (DE) MRI can assess the fibrotic substrate of scar-related VT. MDCT has the advantage of inframillimetric spatial resolution and better 3D reconstructions. We sought to evaluate the feasibility and usefulness of integrating merged MDCT/MRI data in 3D-mapping systems for structure-function assessment and multimodal guidance of VT mapping and ablation.
  
  
  METHODS
  Nine patients, including 3 ischemic cardiomyopathy (ICM), 3 nonischemic cardiomyopathy (NICM), 2 myocarditis, and 1 redo procedure for idiopathic VT, underwent MRI and MDCT before VT ablation. Merged MRI/MDCT data were integrated in 3D-mapping systems and registered to high-density endocardial and epicardial maps. Low-voltage areas (<1.5 mV) and local abnormal ventricular activities (LAVA) during sinus rhythm were correlated to DE at MRI, and wall-thinning (WT) at MDCT.
  
  
  RESULTS
  Endocardium and epicardium were mapped with 391 ± 388 and 1098 ± 734 points per map, respectively. Registration of MDCT allowed visualization of coronary arteries during epicardial mapping/ablation. In the idiopathic patient, integration of MRI data identified previously ablated regions. In ICM patients, both DE at MRI and WT at MDCT matched areas of low voltage (overlap 94 ± 6% and 79 ± 5%, respectively). In NICM patients, wall-thinning areas matched areas of low voltage (overlap 63 ± 21%). In patients with myocarditis, subepicardial DE matched areas of epicardial low voltage (overlap 92 ± 12%). A total number of 266 LAVA sites were found in 7/9 patients. All LAVA sites were associated to structural substrate at imaging (90% inside, 100% within 18 mm).
  
  
  CONCLUSIONS
  The integration of merged MDCT and DEMRI data is feasible and allows combining substrate assessment with high-spatial resolution to better define structure-function relationship in scar-related VT.
authors.affiliation: Department of cardiovascular imaging, CHU/Université de Bordeaux, Pessac, France. hcochet@wanadoo.fr
authors.forename: Hubert
authors.initials: H
authors.lastname: Cochet
authors.forename: Yuki
authors.initials: Y
authors.lastname: Komatsu
authors.forename: Frederic
authors.initials: F
authors.lastname: Sacher
authors.forename: Amir Sherwan
authors.initials: AS
authors.lastname: Jadidi
authors.forename: Daniel
authors.initials: D
authors.lastname: Scherr
authors.forename: Matthieu
authors.initials: M
authors.lastname: Riffaud
authors.forename: Nicolas
authors.initials: N
authors.lastname: Derval
authors.forename: Ashok
authors.initials: A
authors.lastname: Shah
authors.forename: Laurent
authors.initials: L
authors.lastname: Roten
authors.forename: Patrizio
authors.initials: P
authors.lastname: Pascale
authors.forename: Jatin
authors.initials: J
authors.lastname: Relan
authors.forename: Maxime
authors.initials: M
authors.lastname: Sermesant
authors.forename: Nicholas
authors.initials: N
authors.lastname: Ayache
authors.forename: Michel
authors.initials: M
authors.lastname: Montaudon
authors.forename: François
authors.initials: F
authors.lastname: Laurent
authors.forename: Mélèze
authors.initials: M
authors.lastname: Hocini
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.forename: Pierre
authors.initials: P
authors.lastname: Jaïs
mesh_terms: D000328:Adult; D017115:Catheter Ablation / Q000379:methods*; D002921:Cicatrix / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac; D005240:Feasibility Studies; D005260:Female; D005355:Fibrosis; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D006571:Heterocyclic Compounds; D006801:Humans; D021621:Imaging, Three-Dimensional; D007479:Iopamidol / Q000031:analogs & derivatives; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D009942:Organometallic Compounds; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D017180:Tachycardia, Ventricular / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D013813:Therapy, Computer-Assisted; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C057937:iomeprol; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate; D007479:Iopamidol