title: Abnormal two-dimensional strain echocardiography findings in children with congenital valvar aortic stenosis.
abstract: OBJECTIVE
  Congenital valvar aortic stenosis (VAS) causes a pressure overload to the left ventricle. In the clinical setting, the severity of stenosis is graded by the pressure drop over the stenotic valve (pressure gradient). This parameter is dependent on the hemodynamic status and does not provide information regarding myocardial performance. This study was undertaken to reveal the potential of two-dimensional strain echocardiography (2DSTE) for the detection of myocardial functional changes due to congenital VAS in children.
  
  
  METHODS
  A total of 86 patients (aged from birth to 18 years) with various degrees of isolated congenital VAS were enrolled in this study. None of the patients had undergone any form of surgical or balloon intervention. 139 healthy children served as a control group. Two-dimensional cine-loop recordings of apical 4-chamber, mid-cavity short-axis and basal short-axis views were digitally stored for off-line analysis. Longitudinal, circumferential and radial peak systolic strain and strain rate values were determined as well as the time to peak systolic strain (T2P). Two-way analysis of variance was performed to assess the relationship between VAS severity and 2DSTE parameters.
  
  
  RESULTS
  In all patients conventional echocardiographic findings did not indicate systolic left ventricular dysfunction. All strain parameters of the control group were significantly different from those of VAS patients. There was a statistically significant, inverse relationship between global peak systolic strain parameters in all three directions and the degree of VAS (p < 0.05). Local peak systolic strain (rate) in the interventricular septum was most affected. T 2P increased significantly with VAS severity (p < 0.05). The decline in LV longitudinal systolic performance preceded that in other directions.
  
  
  CONCLUSIONS
  2DSTE detects alterations in myocardial function in children diagnosed with congenital VAS, whose conventional echocardiographic findings did not indicate ventricular systolic dysfunction.
authors.affiliation: Children's Heart Centre, Radboud University Nijmegen Medical Centre.
authors.forename: K A
authors.initials: KA
authors.lastname: Marcus
authors.forename: C L
authors.initials: CL
authors.lastname: de Korte
authors.forename: T
authors.initials: T
authors.lastname: Feuth
authors.forename: J M
authors.initials: JM
authors.lastname: Thijssen
authors.forename: L
authors.initials: L
authors.lastname: Kapusta
mesh_terms: D000293:Adolescent; D001021:Aortic Valve / Q000000981:diagnostic imaging; D001024:Aortic Valve Stenosis / Q000151:congenital* / Q000000981:diagnostic imaging*; D001794:Blood Pressure / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography / Q000379:methods*; D018618:Echocardiography, Doppler, Color / Q000379:methods*; D005260:Female; D006346:Heart Septum / Q000000981:diagnostic imaging; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013599:Systole / Q000502:physiology