title: LGE and NT-proBNP identify low risk of death or arrhythmic events in patients with primary prevention ICDs.
abstract: OBJECTIVE
  The aim of this study was to investigate whether late gadolinium enhancement (LGE) magnetic resonance imaging or N-terminal pro-B-type natriuretic peptide (NT-proBNP) could identify patients with a low risk of death or use of implantable cardioverter-defibrillator (ICD) in patients receiving a primary prevention ICD.
  
  
  BACKGROUND
  ICDs reduce mortality in patients with heart failure (HF), although two-thirds may never use their device. Current risk stratification, based on New York Heart Association functional class and left ventricular ejection fraction, still leads to implantation of ICDs in patients who may never need their device.
  
  
  METHODS
  We examined 157 patients with HF (61 with ischemic cardiomyopathy and 96 with dilated cardiomyopathy; mean age 50.5 years; 78% male) who underwent primary prevention defibrillator implantation. Presence and volume of LGE was measured before device implantation, and serum NT-proBNP level was measured before ICD implantation. The combined primary endpoint was cardiovascular death or appropriate ICD therapy (either appropriate shock or antitachycardia pacing).
  
  
  RESULTS
  The primary outcome occurred in 32 patients (20.4%) over a median follow-up period of 915 days. Percentage of LGE (hazard ratio [HR]: per 1% increase: 1.06; 95% confidence interval [CI]: 1.04 to 1.09; p < 0.001) and (ln) NT-proBNP (HR: 1.44; 95% CI: 1.04 to 1.98; p = 0.027) were predictors of death or appropriate ICD activation and remained significant when entered into multivariable analysis. When the cohort was stratified into tertiles based on LGE percentage and NT-proBNP, we were able to identify a low-risk group (event rate 3% per year, compared with the intermediate- and high-risk groups [6% and 10% per year, respectively]).
  
  
  CONCLUSIONS
  Both percentage of LGE and NT-proBNP were associated with higher risk of death or appropriate ICD activation. The use of these markers in combination may be useful in identifying individuals most likely to benefit from this costly intervention, and more specifically, in the identification of a group at lower risk in whom ICD implantation may be deferred.
authors.affiliation: British Heart Foundation Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Ify
authors.initials: I
authors.lastname: Mordi
authors.affiliation: British Heart Foundation Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Pardeep S
authors.initials: PS
authors.lastname: Jhund
authors.affiliation: Golden Jubilee National Hospital, Clydebank, United Kingdom.
authors.forename: Roy S
authors.initials: RS
authors.lastname: Gardner
authors.affiliation: Golden Jubilee National Hospital, Clydebank, United Kingdom.
authors.forename: John
authors.initials: J
authors.lastname: Payne
authors.affiliation: British Heart Foundation Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Carrick
authors.affiliation: British Heart Foundation Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom; Golden Jubilee National Hospital, Clydebank, United Kingdom.
authors.forename: Colin
authors.initials: C
authors.lastname: Berry
authors.affiliation: British Heart Foundation Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom; Golden Jubilee National Hospital, Clydebank, United Kingdom. Electronic address: niko.tzemos@glasgow.ac.uk.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Tzemos
mesh_terms: D017147:Defibrillators, Implantable; D005260:Female; D005682:Gadolinium; D006333:Heart Failure / Q000401:mortality / Q000628:therapy*; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011322:Primary Prevention; D018570:Risk Assessment
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D005682:Gadolinium
keywords: MRI; death; implantable cardioverter-defibrillator (ICD); natriuretic peptides