title: Lower spatial QRS-T angle rules out sustained ventricular arrhythmias in children with hypertrophic cardiomyopathy.
abstract: Introduction The spatial peaks QRS-T angle accurately distinguishes children with hypertrophic cardiomyopathy from their healthy counterparts. The spatial peaks QRS-T angle is also useful in risk stratification for ventricular arrhythmias. We hypothesised that the spatial peaks QRS-T angle would be useful for the prediction of ventricular arrhythmias in hypertrophic cardiomyopathy patients under 23 years of age.
  
  
  METHODS
  Corrected QT interval and spatial peaks QRS-T angles were retrospectively assessed in 133 paediatric hypertrophic cardiomyopathy patients (12.4±6.6 years) with versus without ventricular arrhythmias of 30 seconds or longer. Significance, positive/negative predictive values, and odds ratios were calculated based on receiver operating characteristic curve cut-off values.
  
  
  RESULTS
  In total, 10 patients with ventricular arrhythmias were identified. Although the corrected QT interval did not differentiate those with versus without ventricular arrhythmias, the spatial peaks QRS-T angle did (151.4±19.0 versus 116.8±42.6 degrees, respectively, p<0.001). At an optimal cut-off value (124.1 degrees), the positive and negative predictive values of the spatial peaks QRS-T angle were 15.4 and 100.0%, respectively, with an odds ratio of 25.9 (95% CI 1.5-452.2).
  
  
  CONCLUSIONS
  In children with hypertrophic cardiomyopathy, the spatial peaks QRS-T angle is associated with ventricular arrhythmia burden with high negative predictive value and odds ratio.
authors.affiliation: 1Children's Hospital Colorado/University of Colorado,Aurora,Colorado,United States of America.
authors.forename: Daniel
authors.initials: D
authors.lastname: Cortez
authors.affiliation: 3Penn State Milton Hershey Medical Center,Hershey,Pennsylvania,United States of America.
authors.forename: Nandita
authors.initials: N
authors.lastname: Sharma
authors.affiliation: 1Children's Hospital Colorado/University of Colorado,Aurora,Colorado,United States of America.
authors.forename: Jean
authors.initials: J
authors.lastname: Cavanaugh
authors.affiliation: 4University of California at Irvine,Irvine,California,United States of America.
authors.forename: Froilan
authors.initials: F
authors.lastname: Tuozo
authors.affiliation: 5University of Illinois College of Medicine,Champaign-Urbana,United States of America.
authors.forename: Gwendolyn
authors.initials: G
authors.lastname: Derk
authors.affiliation: 6University of California,Los Angeles,United States of America.
authors.forename: Emily
authors.initials: E
authors.lastname: Lundberg
authors.affiliation: 7CHOC Children's,Orange,California,United States of America.
authors.forename: Keith
authors.initials: K
authors.lastname: Weiner
authors.affiliation: 4University of California at Irvine,Irvine,California,United States of America.
authors.forename: Nafiz
authors.initials: N
authors.lastname: Kiciman
authors.affiliation: 6University of California,Los Angeles,United States of America.
authors.forename: Juan
authors.initials: J
authors.lastname: Alejos
authors.affiliation: 1Children's Hospital Colorado/University of Colorado,Aurora,Colorado,United States of America.
authors.forename: Bruce
authors.initials: B
authors.lastname: Landeck
authors.affiliation: 5University of Illinois College of Medicine,Champaign-Urbana,United States of America.
authors.forename: Jamil
authors.initials: J
authors.lastname: Aboulhosn
authors.affiliation: 1Children's Hospital Colorado/University of Colorado,Aurora,Colorado,United States of America.
authors.forename: Shelley
authors.initials: S
authors.lastname: Miyamoto
authors.affiliation: 7CHOC Children's,Orange,California,United States of America.
authors.forename: Anthony C
authors.initials: AC
authors.lastname: McCanta
authors.affiliation: 4University of California at Irvine,Irvine,California,United States of America.
authors.forename: Anjan S
authors.initials: AS
authors.lastname: Batra
mesh_terms: D000293:Adolescent; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000175:diagnosis; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D014672:Vectorcardiography; D055815:Young Adult
keywords: QTc; Spatial QRS-T angle; hypertrophic cardiomyopathy; prediction; ventricular arrhythmias