title: Repolarization Vector Magnitude Differentiates Kawasaki Disease from Normal Children.
abstract: BACKGROUND
  Kawasaki disease (KD) is the leading cause of acquired heart disease in children. The 12-lead electrocardiogram (ECG) changes in patients during the acute phase of KD include flattened T waves and prolonged corrected QT intervals (QTc). We set out to determine the 12-lead ECG and vectorcardiography predictors for identification of patients with KD and which of these predictors would be clinically useful for early identification of those with coronary artery anomalies (CAA).
  
  
  METHODS
  A blinded, retrospective case-control study of patients with KD and age-matched controls was performed. Deep Q waves, QTc, spatial QRS-T angles, and T-wave vector magnitude (root mean square of the T wave, RMS-T) were assessed. Comparisons between groups were performed to test for significant differences.
  
  
  RESULTS
  Fifty patients with KD (mean age 3.1 ± 3.1 years, 26% female) were compared to 50 previously healthy control patients (mean age 3.8 ± 2.9 years, 44% female). Of the KD patients, 32 (64%) were diagnosed as incomplete KD and 28 (56%) of them had CAA. When compared to the control group, KD patients had abnormal Q waves (72% vs 44% P = 0.005), shorter QTc values (395.1 ± 24.7 ms vs 410.4 ± 34.7 ms, P = 0.013), and lower RMS-T (0.42 ± 0.02 mV vs 0.63 ± 0.03 mV P < 0.001), respectively. Incomplete KD was also discriminated from controls by the same parameters. No differences were noted between KD patients with versus without CAA.
  
  
  CONCLUSIONS
  The RMS-T differentiates complete and incomplete KD from controls. KD patients with CAA were not differentiated from those without CAA.
authors.affiliation: Children's Hospital Colorado, Aurora, CO.|University of Colorado School of Medicine, Aurora, CO.
authors.forename: Daniel
authors.initials: D
authors.lastname: Cortez
authors.affiliation: Children's Hospital Colorado, Aurora, CO.|University of Colorado School of Medicine, Aurora, CO.
authors.forename: Sonali S
authors.initials: SS
authors.lastname: Patel
authors.affiliation: Penn State Milton S. Hershey Medical Center, Hershey, PA.
authors.forename: Nandita
authors.initials: N
authors.lastname: Sharma
authors.affiliation: Children's Hospital Colorado, Aurora, CO.|University of Colorado School of Medicine, Aurora, CO.
authors.forename: Bruce F
authors.initials: BF
authors.lastname: Landeck
authors.affiliation: CHOC Children's, Orange, CA.
authors.forename: Anthony C
authors.initials: AC
authors.lastname: McCanta
authors.affiliation: Children's Hospital Colorado, Aurora, CO.|University of Colorado School of Medicine, Aurora, CO.
authors.forename: Pei-Ni
authors.initials: PN
authors.lastname: Jone
mesh_terms: D016022:Case-Control Studies; D002675:Child, Preschool; D003324:Coronary Artery Disease / Q000209:etiology*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D009080:Mucocutaneous Lymph Node Syndrome / Q000150:complications* / Q000503:physiopathology*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014672:Vectorcardiography
keywords: echo; electrocardiogram; pediatric-electrophysiology