title: Late gadolinium enhancement-cardiovascular magnetic resonance as a predictor of response to cardiac resynchronization therapy in patients with ischaemic cardiomyopathy.
abstract: OBJECTIVE
  To determine whether myocardial scarring, quantified using late gadolinium enhancement-cardiovascular magnetic resonance (LGE-CMR), predicts response to cardiac resynchronization therapy (CRT).
  
  
  RESULTS
  A total of 45 patients with ischaemic cardiomyopathy [age 67.1 +/- 10.4 years (mean +/- SD)] underwent assessment of 6 min walking distance (6MWD) and quality of life (QoL) before and after CRT. Scar size (percentage of left ventricular mass), location, and transmurality were assessed prior to CRT using LGE-CMR. Responders (survived for 1 year with no heart failure hospitalizations, and improvement by >or=1 NYHA classes or >or=25% 6MWD) had a higher left ventricular ejection fraction (P = 0.048), smaller scars (<33%) (P = 0.009), and fewer scars with >or=51% transmurality (P = 0.002). Scar size correlated negatively with change in 6MWD (r = -0.54, P < 0.001) and positively with changes in QoL scores (r = 0.35, P = 0.028). Responder rates in patients with <33% scar were higher than in those with >or=33% scar (82 vs. 35%, P < 0.01). Responder rates in patients with scar transmurality <51% were higher than in those with >or=51% (89 vs. 46%, P < 0.01). Among the patients with posterolateral scars, a transmurality value of >or=51% was associated with a particularly poor response rate (23%), compared with scars with <51% transmurality (88%, P < 0.001). In multivariate analyses, both scar size (P = 0.022) and transmurality (P = 0.004) emerged as predictors of response. In patients with posterolateral scars, pacing outside the scar was associated with a better responder rate than pacing over the scar (86 vs. 33%, P = 0.004).
  
  
  CONCLUSIONS
  In patients with ischaemic cardiomyopathy, a scar size >or=33%, a transmurality >or=51%, and pacing over a posterolateral scar are associated with a suboptimal response to CRT.
authors.affiliation: Department of Cardiology, University of Birmingham, Good Hope Hospital, Rectory Road, Sutton Coldfield, West Midlands B75 7RR, UK.
authors.forename: Shajil
authors.initials: S
authors.lastname: Chalil
authors.forename: Paul W X
authors.initials: PW
authors.lastname: Foley
authors.forename: Sarkaw A
authors.initials: SA
authors.lastname: Muyhaldeen
authors.forename: Kiran C R
authors.initials: KC
authors.lastname: Patel
authors.forename: Zaheer R
authors.initials: ZR
authors.lastname: Yousef
authors.forename: Russell E A
authors.initials: RE
authors.lastname: Smith
authors.forename: Michael P
authors.initials: MP
authors.lastname: Frenneaux
authors.forename: Francisco
authors.initials: F
authors.lastname: Leyva
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D002921:Cicatrix / Q000000981:diagnostic imaging / Q000473:pathology; D004452:Echocardiography; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D005682:Gadolinium; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy*; D009206:Myocardium / Q000473:pathology; D011237:Predictive Value of Tests; D011788:Quality of Life; D016896:Treatment Outcome
chemical_list: D005682:Gadolinium