title: Left ventricular midwall fibrosis as a predictor of mortality and morbidity after cardiac resynchronization therapy in patients with nonischemic cardiomyopathy.
abstract: OBJECTIVE
  The aim of this study was to determine whether left ventricular (LV) midwall fibrosis, detected by midwall hyperenhancement (MWHE) on late gadolinium enhancement cardiovascular magnetic resonance (CMR) imaging, predicts mortality and morbidity in patients with dilated cardiomyopathy (DCM) undergoing cardiac resynchronization therapy (CRT).
  
  
  BACKGROUND
  Midwall fibrosis predicts mortality and morbidity in patients with DCM.
  
  
  METHODS
  Patients with DCM with (+) or without (-) MWHE (n = 20 and n = 77, respectively) as well as 161 patients with ischemic cardiomyopathy (ICM) undergoing CRT (n = 258) were followed up for a maximum of 8.7 years.
  
  
  RESULTS
  Among patients with DCM, +MWHE predicted cardiovascular mortality (hazard ratio [HR]: 18.6; 95% confidence intervals [CI]: 3.51 to 98.5; p = 0.0008), total mortality or hospitalization for major adverse cardiovascular events (HR: 7.57; 95% CI: 2.71 to 21.2; p < 0.0001), and cardiovascular mortality or heart failure hospitalizations (HR: 9.56; 95% CI: 2.72 to 33.6; p = 0.0004), independent of New York Heart Association class, QRS duration, atrial fibrillation, LV volumes, LV ejection fraction, and a CMR-derived measure of dyssynchrony. Among patients with DCM and ICM, the risk of cardiovascular mortality for DCM +MWHE (adjusted HR: 18.5; 95% CI: 3.93 to 87.3; p = 0.0002) was similar to that for ICM (adjusted HR: 21.0; 95% CI: 5.06 to 87.2; p < 0.0001). Both DCM +MWHE and ICM were predictors of pump failure death as well as sudden cardiac death. LV reverse remodeling was observed in DCM -MWHE and in ICM but not in DCM +MWHE.
  
  
  CONCLUSIONS
  Midwall fibrosis is an independent predictor of mortality and morbidity in patients with DCM undergoing CRT. The outcome of DCM with midwall fibrosis is similar to that of ICM. This relationship is mediated by both pump failure and sudden cardiac death.
authors.affiliation: Centre for Cardiovascular Sciences, Queen Elizabeth Hospital, University of Birmingham, Birmingham, United Kingdom. cardiologists@hotmail.com
authors.forename: Francisco
authors.initials: F
authors.lastname: Leyva
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Taylor
authors.forename: Paul W X
authors.initials: PW
authors.lastname: Foley
authors.forename: Fraz
authors.initials: F
authors.lastname: Umar
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Mulligan
authors.forename: Kiran
authors.initials: K
authors.lastname: Patel
authors.forename: Berthold
authors.initials: B
authors.lastname: Stegemann
authors.forename: Tarek
authors.initials: T
authors.lastname: Haddad
authors.forename: Russell E A
authors.initials: RE
authors.lastname: Smith
authors.forename: Sanjay K
authors.initials: SK
authors.lastname: Prasad
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy; D009202:Cardiomyopathies / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D005355:Fibrosis / Q000401:mortality; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000473:pathology*; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D006113:United Kingdom / Q000453:epidemiology; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000453:epidemiology*