title: The synthesized vectorcardiogram resembles the measured vectorcardiogram in patients with dyssynchronous heart failure.
abstract: BACKGROUND
  The use of vectorcardiography (VCG) has regained interest, however, original Frank-VCG equipment is rare. This study compares the measured VCGs with those synthesized from the 12-lead electrocardiogram (ECG) in patients with heart failure and conduction abnormalities, who are candidate for cardiac resynchronization therapy (CRT).
  
  
  METHODS
  In 92 CRT candidates, Frank-VCG and 12-lead ECG were recorded before CRT implantation. The ECG was converted to a VCG using the Kors method (Kors-VCG) and the two methods were compared using correlation and Bland-Altman analyses.
  
  
  RESULTS
  Variables calculated from the Frank- and Kors-VCG showed correlation coefficients between 0.77 and 0.90. There was a significant but small underestimation by the Kors-VCG method, relative bias ranging from -1.9% ± 4.6% (QRS-T angle) to -9.4% ± 20.8% (T area).
  
  
  CONCLUSIONS
  The present study shows that it is justified to use Kors-VCG calculations for VCG analysis, which enables retrospective VCG analysis of previously recorded ECGs in studies related to CRT.
authors.affiliation: Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands.
authors.forename: Elien B
authors.initials: EB
authors.lastname: Engels
authors.affiliation: Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands.
authors.forename: Salih
authors.initials: S
authors.lastname: Alshehri
authors.affiliation: Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands; Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands.
authors.forename: Caroline J M
authors.initials: CJ
authors.lastname: van Deursen
authors.affiliation: Department of Cardiology, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Liliane
authors.initials: L
authors.lastname: Wecke
authors.affiliation: Sahlgrenska Academy, Department of Molecular and Clinical Medicine/Cardiology, University of Gothenburg, Sweden.
authors.forename: Lennart
authors.initials: L
authors.lastname: Bergfeldt
authors.affiliation: Department of Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands.
authors.forename: Kevin
authors.initials: K
authors.lastname: Vernooy
authors.affiliation: Department of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands. Electronic address: frits.prinzen@maastrichtuniversity.nl.
authors.forename: Frits W
authors.initials: FW
authors.lastname: Prinzen
mesh_terms: D000368:Aged; D000465:Algorithms; D003198:Computer Simulation; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006333:Heart Failure / Q000175:diagnosis* / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008955:Models, Cardiovascular; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014672:Vectorcardiography / Q000379:methods*
keywords: Cardiac resynchronization therapy; Electrical dyssynchrony; Kors method; Vectorcardiography