title: Recoordination rather than resynchronization predicts reverse remodeling after cardiac resynchronization therapy.
abstract: BACKGROUND
  Mechanical discoordination as studied by magnetic resonance imaging has been shown to be a better predictor of left ventricular (LV) reverse remodeling after cardiac resynchronization therapy (CRT) compared with mechanical dyssynchrony.
  
  
  METHODS
  This study assessed the value of acute recoordination derived from speckle-tracking echocardiography for predicting response to CRT compared with acute resynchronization. Thirty patients with heart failure scheduled for CRT were studied at baseline, immediately after CRT, and after 6 months of CRT. Acute recoordination after CRT was indexed by an acute reduction in radial discoordination index (RDI), defined as the ratio of average myocardial thinning to thickening during the ejection phase.
  
  
  RESULTS
  CRT responders were defined as those patients whose LV end-systolic volume decreased by >or= 15% at the 6-month follow-up. Immediately after CRT, the responders (n = 18) demonstrated a significant reduction in RDI (P < .001), which was sustained at the 6-month follow-up (P < .001). The nonresponders, however, did not show a significant change in RDI after CRT. LV reverse remodeling at the 6-month follow-up was significantly correlated with acute recoordination (r = 0.75, P < .001) but weakly correlated with acute resynchronization (r = 0.43; P = .02).
  
  
  CONCLUSIONS
  Receiver operating characteristic analysis revealed that acute recoordination provided the best separation for prediction of CRT responders compared with acute resynchronization, baseline dyssynchrony, or baseline discoordination. LV recoordination after CRT is an acute phenomenon and predicts response to CRT at 6-month follow-up better than resynchronization.
authors.affiliation: First Division of Cardiovascular Department, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.
authors.forename: Chun-Li
authors.initials: CL
authors.lastname: Wang
authors.forename: Chia-Tung
authors.initials: CT
authors.lastname: Wu
authors.forename: Yung-Hsin
authors.initials: YH
authors.lastname: Yeh
authors.forename: Lung-Sheng
authors.initials: LS
authors.lastname: Wu
authors.forename: Chi-Jen
authors.initials: CJ
authors.lastname: Chang
authors.forename: Wan-Jing
authors.initials: WJ
authors.lastname: Ho
authors.forename: Lung-An
authors.initials: LA
authors.lastname: Hsu
authors.forename: Nazar
authors.initials: N
authors.lastname: Luqman
authors.forename: Chi-Tai
authors.initials: CT
authors.lastname: Kuo
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000150:complications / Q000628:therapy*; D002304:Cardiac Pacing, Artificial; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000628:therapy*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D020257:Ventricular Remodeling