title: Late gadolinium enhancement cardiac magnetic resonance imaging for the prediction of ventricular tachyarrhythmic events: a meta-analysis.
abstract: OBJECTIVE
  Approaches to the risk stratification for sudden cardiac death (SCD) remain unsatisfactory. Although late gadolinium enhancement cardiac magnetic resonance imaging (LGE-CMR) for SCD risk stratification has been evaluated in several studies, small sample size has limited their clinical validity. We performed this meta-analysis to better gauge the predictive accuracy of LGE-CMR for SCD risk stratification.
  
  
  RESULTS
  Electronic databases and published bibliographies were systematically searched to identify studies evaluating the association between the extent of LV scar on LGE-CMR and ventricular arrhythmic events [SCD, resuscitated cardiac arrest, the occurrence of ventricular arrhythmias, or appropriate implantable cardioverter defibrillator (ICD) therapy]. Only studies enrolling patients with CAD or non-ischaemic cardiomyopathy were included. Summary estimates of the relative risk (RR) and likelihood ratios (LRs) were calculated using random effects models. Eleven studies comprising 1105 patients were identified. During a mean/median follow-up of 8.5-41 months 207 patients had ventricular arrhythmic events. Ventricular arrhythmic events were more common in patients with a greater extent of LV scar: RR 4.33 [95% confidence interval (CI) 2.98-6.29], positive LR 1.98 (95% CI 1.66-2.37), and negative LR 0.33 (95% CI 0.24-0.46).
  
  
  CONCLUSIONS
  The extent of LGE on CMR is strongly associated with the occurrence of ventricular arrhythmias in patients with reduced LVEF and may be a valuable risk stratification tool for identifying patients who will benefit from ICD therapy. However, uncertainties regarding clinical application persist and need to be addressed prior to introduction into broad clinical practice.
authors.affiliation: Wessex Cardiothoracic Unit, University Hospital Southampton NHS Foundation Trust, UK. paul.andrew.scott@btinternet.com
authors.forename: Paul A
authors.initials: PA
authors.lastname: Scott
authors.forename: James A
authors.initials: JA
authors.lastname: Rosengarten
authors.forename: Nick P
authors.initials: NP
authors.lastname: Curzen
authors.forename: John M
authors.initials: JM
authors.lastname: Morgan
mesh_terms: D016757:Death, Sudden, Cardiac / Q000209:etiology; D017147:Defibrillators, Implantable; D005682:Gadolinium; D006352:Heart Ventricles / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D018570:Risk Assessment; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000209:etiology / Q000628:therapy
chemical_list: D005682:Gadolinium
keywords: Arrhythmia; Coronary artery disease; Death, sudden; Implantable cardioverter defibrillator; Magnetic resonance imaging; Meta-analysis