title: The influence of myocardial scar and dyssynchrony on reverse remodeling in cardiac resynchronization therapy.
abstract: OBJECTIVE
  The influence of location and extent of transmural scar and its relation with dyssynchrony in cardiac resynchronization therapy (CRT) was investigated as posterolateral scar tissue has been invoked as a cause of non-response to CRT.
  
  
  RESULTS
  Fifty-seven patients eligible for CRT were assessed for transmural scar with gadolinium-enhanced MRI and for left ventricular (LV) dyssynchrony with tissue Doppler. After implant, both atrioventricular and interventricular pacing intervals were optimized. LV reverse remodeling was defined as >/=10% decrease in LV end-systolic volume after 3 months. Sixteen patients had transmural scar in the posterolateral (PL) area (LV lead location), 14 at a remote site (non-PL) and 27 patients had no scar. LV reverse remodeling was observed in respectively 25%, 64% and 89% (P = 0.0001). Univariate analyses showed a relation with LV dyssynchrony (P = 0.004) and with absence of PL scar (P = 0.04) but not with QRS duration and the extent of LV scar tissue. In multivariate analysis, only LV dyssynchrony (OR: 19.62; 95% CI: 2.5-151.9; P = 0.004) independently predicted LV reverse remodeling.
  
  
  CONCLUSIONS
  In this study LV dyssynchrony remains the most important determinant of response to CRT, even in the presence of posterolateral scar provided atrioventricular and interventricular pacing intervals are optimized.
authors.affiliation: Department of Cardiology, Catharina Hospital, Michelangelolaan 2, P.O. Box 1350, 5602 ZA Eindhoven, The Netherlands. annemieke.jansen@cze.nl
authors.forename: Annemieke H M
authors.initials: AH
authors.lastname: Jansen
authors.forename: Frank
authors.initials: F
authors.lastname: Bracke
authors.forename: Jan Melle
authors.initials: JM
authors.lastname: van Dantzig
authors.forename: Kathinka H
authors.initials: KH
authors.lastname: Peels
authors.forename: Johannes C
authors.initials: JC
authors.lastname: Post
authors.forename: Harrie C M
authors.initials: HC
authors.lastname: van den Bosch
authors.forename: Berry
authors.initials: B
authors.lastname: van Gelder
authors.forename: Albert
authors.initials: A
authors.lastname: Meijer
authors.forename: Hendrikus H M
authors.initials: HH
authors.lastname: Korsten
authors.forename: Jolanda
authors.initials: J
authors.lastname: de Vries
authors.forename: Norbert M
authors.initials: NM
authors.lastname: van Hemel
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial; D002921:Cicatrix; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis / Q000628:therapy*; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000209:etiology / Q000628:therapy*; D020257:Ventricular Remodeling