title: Echocardiographic assessment of the right ventricular response to hypertension in neonates on the basis of average-shaped contraction models.
abstract: METHODS
  We evaluated a new method of shape analysis in defining right ventricle (RV) response to pressure overload. Twenty-five neonatal patients (13 with RV hypertension, 12 without) underwent echocardiographic imaging and reconstruction of RV regional chamber volumes over 1 cardiac cycle. Group tracing data in coronal, sagittal, and transverse echocardiography planes were then shape-averaged to construct normal- and hypertensive-average-shape contraction models. Each patient's RV was classified as more similar to the normal- or hypertensive-average-shape model on the basis of the median tangent-angle difference, a quantitative technique of shape comparison.
  
  
  RESULTS
  Ejection fraction, time of end systole, and ejection rate demonstrated significant regional differences between normotensive and hypertensive contractions. The normal-average-shape contraction model correctly diagnosed all patients who were normotensive (specificity 100%) and the hypertensive-average-shape model identified 11 of 13 patients who were hypertensive (sensitivity 85%).
  
  
  CONCLUSIONS
  Reconstructed-shape contraction models throughout 1 cardiac cycle identify altered patterns of RV contraction in the presence of pulmonary hypertension.
authors.affiliation: Department of Cardiology, Children's Hospital and the Department of Pediatrics, Harvard Medical School, Boston, USA.
authors.forename: Edward N
authors.initials: EN
authors.lastname: Marcus
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Munoz
authors.forename: Renee
authors.initials: R
authors.lastname: Margossian
authors.forename: Steven D
authors.initials: SD
authors.lastname: Colan
authors.forename: David L
authors.initials: DL
authors.lastname: Wessel
mesh_terms: D004452:Echocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D006973:Hypertension / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D007231:Infant, Newborn / Q000502:physiology*; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013318:Stroke Volume / Q000502:physiology; D016278:Ventricular Function, Right / Q000502:physiology*