title: In Hypertrophic Cardiomyopathy, the Spatial Peaks QRS-T Angle Identifies Those With Sustained Ventricular Arrhythmias.
abstract: BACKGROUND
  The spatial peaks QRS-T (SPQRS-T) angle differentiates hypertrophic cardiomyopathy (HCM) patients from controls. Increased angle confers arrhythmia risk in other populations.
  
  
  OBJECTIVE
  We predict that the SPQRS-T angle will identify HCM patients with sustained ventricular arrhythmias (VAs) and those with New York Heart Association class III/IV heart failure.
  
  
  METHODS
  Corrected QT interval, QRS duration, and SPQRS-T angle were assessed in HCM patients with VAs (>30 seconds) and those without VAs.
  
  
  RESULTS
  One hundred HCM patients (mean age, 32.7 ± 17.2 years) were assessed. Twenty patients had VAs. The corrected QT interval identified VA (P = 0.018) and at 460 ms gave positive and negative predictive values of 28.6% and 83.3%, respectively, and an odds ratio of 2.0 (95% confidence interval: 0.7-5.6). The SPQRS-T angle differentiated VA from no VA (P < 0.001) and at 124.1 degrees gave positive and negative predictive values and an odds ratio of 36.7%, 96.1%, and 14.2 (95% confidence interval: 3.1-65.6), respectively.
  
  
  CONCLUSIONS
  The SPQRS-T angle best differentiated patients with VAs.
authors.affiliation: Department of Pediatric Cardiology, Children's Hospital of Colorado/University of Colorado, Aurora, Colorado.|Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: Daniel
authors.initials: D
authors.lastname: Cortez
authors.affiliation: Cardiovascular Institute and Adult Medical Genetics Program, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado.
authors.forename: Sharon
authors.initials: S
authors.lastname: Graw
authors.affiliation: Cardiovascular Institute and Adult Medical Genetics Program, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado.
authors.forename: Luisa
authors.initials: L
authors.lastname: Mestroni
mesh_terms: D000200:Action Potentials; D000293:Adolescent; D000328:Adult; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006333:Heart Failure / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D006339:Heart Rate; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult