title: Filtered QRS duration on signal-averaged electrocardiography correlates with ventricular dyssynchrony assessed by tissue Doppler imaging in patients with reduced ventricular ejection fraction.
abstract: OBJECTIVE
  The relationships between filtered QRS duration and ventricular dyssynchrony were studied.
  
  
  METHODS
  We measured filtered QRS duration on signal-averaged electrocardiography and analyzed tissue Doppler imaging in chronic heart failure patients with ejection fraction less than 50%.
  
  
  RESULTS
  In 64 patients, interventricular and intraventricular dyssynchronies were observed in 25 and 38 patients, respectively. All patients with interventricular dyssynchrony were associated with intraventricular dyssynchrony. Filtered QRS showed 0.82 and 0.78 of the area under the curve (AUC) in the receiver operating characteristic curve (ROC) for the detection of interventricular and intraventricular dyssynchrony, respectively, with 89.7% and 96.2% specificity and 52.0% and 52.6% sensitivity, with cutoff values of 174 and 153 milliseconds. Specificity and sensitivity as well as AUC were lower in the ROC of QRS duration than filtered QRS duration.
  
  
  CONCLUSIONS
  Filtered QRS duration provided more reliable information to estimate ventricular dyssynchrony in patients with reduced ventricular ejection fraction than QRS duration did.
authors.affiliation: Division of Cardiology, Takamatsu Red Cross Hospital, Takamatsu, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Tahara
authors.forename: Taiji
authors.initials: T
authors.lastname: Sogou
authors.forename: Chisato
authors.initials: C
authors.lastname: Suezawa
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Matsubara
authors.forename: Norihiro
authors.initials: N
authors.lastname: Tada
authors.forename: Sho
authors.initials: S
authors.lastname: Tsushima
authors.forename: Tomoki
authors.initials: T
authors.lastname: Kitawaki
authors.forename: Ryoko
authors.initials: R
authors.lastname: Shinohata
authors.forename: Shozo
authors.initials: S
authors.lastname: Kusachi
mesh_terms: D000368:Aged; D000465:Algorithms; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004452:Echocardiography / Q000379:methods*; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D013223:Statistics as Topic; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis*