title: Prevalence of myocardial fibrosis patterns in patients with systolic dysfunction: prognostic significance for the prediction of sudden cardiac arrest or appropriate implantable cardiac defibrillator therapy.
abstract: BACKGROUND
  Late gadolinium enhancement-cardiac magnetic resonance is increasingly performed in patients with systolic dysfunction. Numerous patterns of fibrosis are commonly reported among this population. However, the relative prevalence and prognostic significance of these findings remains uncertain.
  
  
  RESULTS
  Three hundred eighteen consecutive patients referred for late gadolinium enhancement-cardiac magnetic resonance and a left ventricular ejection fraction <55% were followed up for the primary end point of sudden cardiac arrest or appropriate implantable cardiac defibrillator therapy. Late gadolinium enhancement images were blindly interpreted for the presence of 6 distinct pattern(s) of myocardial fibrosis in addition to signal threshold-based quantification of total fibrosis volume. The mean age and left ventricular ejection fraction of participants were 62.0±12.9 years and 32.6±11.9%, respectively. Any pattern of myocardial fibrosis was seen in 248 patients (78%) with ≥2 patterns present in 25% of patients. During follow-up (median of 467 days), 49 patients (15%) had a primary outcome. After adjustment for left ventricular ejection fraction, cardiomyopathy pathogenesis, and total fibrosis volume, the presence of a midwall striae pattern of fibrosis was an independent predictor of sudden cardiac arrest or appropriate implantable cardiac defibrillator therapy with a hazard ratio of 2.4 (95% confidence interval, 1.2-4.6; P=0.01); this finding is present in 30% of patients with nonischemic and 15% of patients with ischemic cardiomyopathy. Cumulative event rate was significantly higher among those with midwall striae, particularly among those with a left ventricular ejection fraction >35% (40% versus 6%; P=0.005).
  
  
  CONCLUSIONS
  Patients with systolic dysfunction frequently demonstrate multiple patterns of myocardial fibrosis. Of these, a midwall striae pattern of fibrosis is the strongest independent predictor of sudden cardiac arrest or appropriate implantable cardiac defibrillator therapy.
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada.
authors.forename: Fahad
authors.initials: F
authors.lastname: Almehmadi
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada.
authors.forename: Sebastien Xavier
authors.initials: SX
authors.lastname: Joncas
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada.
authors.forename: Immaculate
authors.initials: I
authors.lastname: Nevis
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Zahrani
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Bokhari
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada.
authors.forename: John
authors.initials: J
authors.lastname: Stirrat
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada.
authors.forename: Nowell M
authors.initials: NM
authors.lastname: Fine
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada.
authors.forename: Raymond
authors.initials: R
authors.lastname: Yee
authors.affiliation: From the Division of Internal Medicine, Department of Medicine, London Health Sciences Centre, London, Ontario, Canada (F.A., M.Z., M.B., R.Y., N.M.F., J.A.W.); Department of Medicine, Stephenson Cardiovascular MR Centre at the Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada (S.X.J., N.M.F., J.A.W.); and Imaging Research Laboratory, Robarts Research Institute (I.N., J.S.) and Lawson Health Research Institute (I.N.), Western University, London, Ontario, Canada. jawhit@ucalgary.ca.
authors.forename: James A
authors.initials: JA
authors.lastname: White
mesh_terms: D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D017147:Defibrillators, Implantable; D004719:Endomyocardial Fibrosis / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D054143:Heart Failure, Systolic / Q000150:complications* / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D015995:Prevalence; D011446:Prospective Studies; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends
keywords: death, sudden, cardiac; fibrosis; magnetic resonance imaging