title: Left-right ventricular interactions in pediatric aortic stenosis: right ventricular myocardial strain before and after aortic valvuloplasty.
abstract: BACKGROUND
  Ventricular-ventricular interactions may affect left ventricular (LV) and right ventricular (RV) function but have not been well characterized in chronic LV afterload in children. The aim of this study was to assess RV myocardial strain in children with aortic stenosis before and after aortic balloon valvuloplasty.
  
  
  METHODS
  Two-dimensional echocardiographic images from children aged > 1 month were with aortic stenosis and preserved LV ejection fractions were retrospectively studied using vector velocity imaging. LV and RV strain were compared before and after balloon valvuloplasty and in comparison with normal controls.
  
  
  RESULTS
  Twenty-six children were studied. Aortic valve gradient decreased after balloon valvuloplasty. LV ejection fraction, wall thickness, circumferential strain, and basal and mid longitudinal strain were unchanged after valvuloplasty (-18.09 ± 6.97% vs -16.43 ± 6.30%, P = .40, and -14.11 ± 5.011% vs -13.12 ± 5.52%, P = .50, respectively). LV strain tended to be lower than in controls after valvuloplasty (basal, -16.43 ± 6.30% vs -19.77 ± 5.82%, P = .05). RV strain was unchanged at the basal and apical segments but increased at the mid RV segment after valvuloplasty (-21.34 ± 6.55% vs -24.97 ± 8.54%, P = .02). Change in RV strain was not correlated with change in aortic gradient or change in LV strain after valvuloplasty (P = .60). LV and RV strain at baseline and their changes after valvuloplasty were variable between patients.
  
  
  CONCLUSIONS
  RV strain was normal or reduced in compensated aortic stenosis and was not correlated with LV strain. The change in RV strain was variable among patients after valvuloplasty, with improvement in RV midwall longitudinal strain.
authors: Division of Pediatric Cardiology, The Labatt Family Heart Center, Hospital for Sick Children and Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada. mark.friedberg@sickkids.ca
authors: Mark K
authors: MK
authors: Friedberg
authors: Stephen
authors: S
authors: Wu
authors: Cameron
authors: C
authors: Slorach
mesh_terms: D000293:Adolescent; D001024:Aortic Valve Stenosis / Q000628:therapy*; D063126:Balloon Valvuloplasty; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011184:Postoperative Period; D057234:Preoperative Period; D012189:Retrospective Studies; D018497:Ventricular Dysfunction, Right; D016276:Ventricular Function / Q000502:physiology*