title: Prediction of arrhythmic events in ischemic and dilated cardiomyopathy patients referred for implantable cardiac defibrillator: evaluation of multiple scar quantification measures for late gadolinium enhancement magnetic resonance imaging.
abstract: BACKGROUND
  Scar signal quantification using late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) identifies patients at higher risk of future events, both in ischemic cardiomyopathy (ICM) and nonischemic dilated cardiomyopathy (DCM). However, the ability of scar signal burden to predict events in such patient groups at the time of referral for implantable cardioverter-defibrillator (ICD) has not been well explored. This study evaluates the predictive use of multiple scar quantification measures in ICM and DCM patients being referred for ICD.
  
  
  RESULTS
  One hundred twenty-four consecutive patients referred for ICD therapy (59 with ICM and 65 with DCM) underwent a standardized LGE-CMR protocol with blinded, multithreshold scar signal quantification and, for those with ICM, peri-infarct signal quantification. Patients were followed prospectively for the primary combined outcome of appropriate ICD therapy, survived cardiac arrest, or sudden cardiac death. At a mean follow-up of 632 ± 262 days, 18 patients (15%) had suffered the primary outcome. Total scar was significantly higher among those suffering a primary outcome, a relationship maintained within each cardiomyopathy cohort (P<0.01 for all comparisons). Total scar was the strongest independent predictor of the primary outcome and demonstrated a negative predictive value of 86%. In the ICM subcohort, peri-infarct signal showed only a nonsignificant trend toward elevation among those having a primary end point.
  
  
  CONCLUSIONS
  Myocardial scar quantification by LGE-CMR predicts arrhythmic events in patients being evaluated for ICD eligibility irrespective of cardiomyopathy etiology.
authors.affiliation: Division of Cardiology, Department of Medicine, University of Western Ontario, London, Ontario, Canada.
authors.forename: Peng
authors.initials: P
authors.lastname: Gao
authors.forename: Raymond
authors.initials: R
authors.lastname: Yee
authors.forename: Lorne
authors.initials: L
authors.lastname: Gula
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Krahn
authors.forename: Allan
authors.initials: A
authors.lastname: Skanes
authors.forename: Peter
authors.initials: P
authors.lastname: Leong-Sit
authors.forename: George J
authors.initials: GJ
authors.lastname: Klein
authors.forename: John
authors.initials: J
authors.lastname: Stirrat
authors.forename: Nowell
authors.initials: N
authors.lastname: Fine
authors.forename: Luljeta
authors.initials: L
authors.lastname: Pallaveshi
authors.forename: Gerald
authors.initials: G
authors.lastname: Wisenberg
authors.forename: Terry R
authors.initials: TR
authors.lastname: Thompson
authors.forename: Frank
authors.initials: F
authors.lastname: Prato
authors.forename: Maria
authors.initials: M
authors.lastname: Drangova
authors.forename: James A
authors.initials: JA
authors.lastname: White
mesh_terms: D001145:Arrhythmias, Cardiac / Q000503:physiopathology* / Q000517:prevention & control*; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology* / Q000628:therapy*; D002921:Cicatrix / Q000473:pathology*; D003287:Contrast Media; D017023:Coronary Angiography; D003627:Data Interpretation, Statistical; D017147:Defibrillators, Implantable; D004452:Echocardiography; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology*; D017202:Myocardial Ischemia / Q000503:physiopathology* / Q000628:therapy*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012017:Referral and Consultation; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D015996:Survival Rate; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA