title: Measurements of electrical and mechanical dyssynchrony are both essential to improve prediction of CRT response.
abstract: BACKGROUND
  Predicting reverse remodeling after cardiac resynchronization therapy (CRT) remains challenging and different etiologies of heart failure might hamper identification of predictors.
  
  
  OBJECTIVE
  Assess the incremental value of mechanical dyssynchrony besides electrical dyssynchrony for predicting CRT response.
  
  
  METHODS
  227 patients (51% ischemic) received CRT. Response was defined as ≥15% left ventricular end systolic volume decrease after six months. Prediction models were developed comprising clinical parameters and electrical dyssynchrony (Model A), subsequently complemented with mechanical dyssynchrony (Model B). Models were compared by area under the receiver-operating curve (AUC), net reclassification index (NRI) and integrated discrimination improvement (IDI) for the complete cohort, ischemic (ICM) and non-ischemic (NICM) subpopulations.
  
  
  RESULTS
  Model B performed significantly better than Model A supported by AUC, NRI and IDI. Furthermore, model B significantly better predicted response for NICM than ICM.
  
  
  CONCLUSIONS
  Electrical dyssynchrony and mechanical dyssynchrony are essential to predict CRT response. Nevertheless, response prediction for ICM remains challenging.
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: j.vantsant@umcutrecht.nl.
authors.forename: J
authors.initials: J
authors.lastname: Van't Sant
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: I A H
authors.initials: IA
authors.lastname: Ter Horst
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: S C
authors.initials: SC
authors.lastname: Wijers
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: T P
authors.initials: TP
authors.lastname: Mast
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: G E
authors.initials: GE
authors.lastname: Leenders
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: P A
authors.initials: PA
authors.lastname: Doevendans
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: M J
authors.initials: MJ
authors.lastname: Cramer
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Meine
mesh_terms: D000368:Aged; D017147:Defibrillators, Implantable; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D004452:Echocardiography / Q000379:methods; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*; D006801:Humans; D008297:Male; D017063:Outcome Assessment, Health Care / Q000379:methods; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*
keywords: Cardiac resynchronization therapy; Electrical dyssynchrony; Mechanical dyssynchrony