title: Selection of patient for cardiac resynchronization therapy: role of QT corrected dispersion.
abstract: OBJECTIVE
  About 30 to 50% of patients undergoing cardiac resynchronization therapy (CRT) may not show clinical or echocardiographic improvement, despite fulfilling guidelines recommendations for CRT. For this reason, we need a more accurate method to assess CRT eligibility. The aims of this study were to verify, on a 12-month follow-up, the usefulness of QT corrected dispersion (QTcD) in a patient's selection for CRT.
  
  
  METHODS
  We stratified 53 patients who underwent CRT, into two groups based on the estimation of QTcD, that is, QTcD > 60 ms and QTcD ≤ 60 ms. In all patients were performed New York Heart Association (NYHA) class determination, six-minute walking test, QtcD, and QRS measurements, and complete echocardiographic assessment at 1, 3, 6, and 12 months after implantation.
  
  
  RESULTS
  At baseline, there were no significant differences in clinical, echocardiographic, and electrocardiographic parameters duration between two groups. At 12-month follow-up between the two groups, there were significant differences in NYHA (1.2 ± 0.4 vs 2 ± 0.6; P < 0.01), six-minute walking distance (422 ± 68 vs 364 ± 68; P < 0.01), left ventricular (LV) ejection fraction (34 ± 7% vs 28 ± 6%; P < 0.01), LV end-diastolic diameter (57 ± 7 vs 63 ± 8; P < 0.01), and LV intraventricular dyssynchrony (24 ± 14 vs 39 ± 23; P < 0.01).
  
  
  CONCLUSIONS
  This study suggests that QTc dispersion in addition to QRS duration could improve the sensitivity of electrocardiogram in a patient's selection for CRT.
authors.affiliation: Electrophysiology Unit, Cardiology Department, Ferrarotto Hospital, University of Catania, Catania, Italy. salvotimineri@hotmail.it
authors.forename: Salvatore
authors.initials: S
authors.lastname: Timineri
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Mulè
authors.forename: Euglena
authors.initials: E
authors.lastname: Puzzangara
authors.forename: Gloria
authors.initials: G
authors.lastname: Santangelo
authors.forename: Daniela
authors.initials: D
authors.lastname: Dugo
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Schillaci
authors.forename: Angelo
authors.initials: A
authors.lastname: Di Grazia
authors.forename: Caudio
authors.initials: C
authors.lastname: Liotta
authors.forename: Salvatore
authors.initials: S
authors.lastname: Scandura
authors.forename: Donatella
authors.initials: D
authors.lastname: Tempio
authors.forename: Corrado
authors.initials: C
authors.lastname: Tamburino
authors.forename: Valeria
authors.initials: V
authors.lastname: Calvi
mesh_terms: D058406:Cardiac Resynchronization Therapy; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis* / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis* / Q000517:prevention & control*