title: Septal to posterior wall motion delay fails to predict reverse remodeling or clinical improvement in patients undergoing cardiac resynchronization therapy.
abstract: OBJECTIVE
  The aim of this study was to test the hypothesis that a longer septal-to-posterior wall motion delay (SPWMD) would predict greater reverse remodeling and an improved clinical response in heart failure patients randomized to cardiac resynchronization therapy (CRT) in the CONTAK-CD trial.
  
  
  BACKGROUND
  The SPWMD predicted clinical benefit with CRT in two previous studies from the same center.
  
  
  METHODS
  In this retrospective analysis of the CONTAK-CD trial, SPWMD was measured from the baseline echocardiogram of 79 heart failure patients (ejection fraction 22 +/- 7%, QRS duration 159 +/- 27 ms, 72% ischemic, 84% male) randomized to CRT and compared with six-month changes in echocardiographic and clinical parameters. Patients with a left ventricular end-systolic volume index (LVESVI) reduction of at least 15% were considered responders.
  
  
  RESULTS
  The feasibility and reproducibility of performing the SPWMD measurements were poor. Larger values for SPWMD did not correlate with six-month changes in left ventricular end-diastolic volume index (p = 0.26), LVESVI (p = 0.41), or left ventricular ejection fraction (p = 0.36). Responders did not have a significantly different SPWMD than non-responders (p = 0.26). The SPWMD did not correlate with measures of clinical improvement. At a threshold of SPWMD >130 ms, the test characteristics to predict reverse remodeling or a clinical response were inadequate.
  
  
  CONCLUSIONS
  The previous findings that SPWMD predicts reverse remodeling or clinical improvement with CRT were not reproducible in patients randomized in the CONTAK-CD trial.
authors.affiliation: Department of Medicine, Division of Cardiology, University of California, San Francisco, San Francisco, California, USA.
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Marcus
authors.forename: Emily
authors.initials: E
authors.lastname: Rose
authors.forename: Esperanza M
authors.initials: EM
authors.lastname: Viloria
authors.forename: Jill
authors.initials: J
authors.lastname: Schafer
authors.forename: Teresa
authors.initials: T
authors.lastname: De Marco
authors.forename: Leslie A
authors.initials: LA
authors.lastname: Saxon
authors.forename: Elyse
authors.initials: E
authors.lastname: Foster
mesh_terms: D000368:Aged; D002303:Cardiac Output, Low / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D002304:Cardiac Pacing, Artificial; D004452:Echocardiography; D005240:Feasibility Studies; D005260:Female; D006346:Heart Septum / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000209:etiology*; D020257:Ventricular Remodeling