title: Assessing Fetal Cardiac Function by Measuring Myocardial Radial Velocity Using the Phased-Tracking Method.
abstract: OBJECTIVE
  This study aimed to assess the cardiac function of healthy and pathological fetuses by measuring radial velocity using phased tracking (PT). Based on phase differences, PT allows the displacement of a specified point to be detected with improved spatial and temporal resolution.
  
  
  METHODS
  PT was used to assess cardiac radial velocity in the basal free wall of the left and right ventricles in 134 healthy fetuses, 10 second-trimester intrauterine growth-restricted (IUGR) fetuses, and 10 recipient twins with twin-to-twin transfusion syndrome (TTTS). Maximum velocities were measured in systole and early diastole.
  
  
  RESULTS
  Maximum radial velocity was successfully measured in 126 healthy fetuses (94%) at gestational ages of 16-40 weeks. Systolic and early diastolic maximum velocities increased with gestational age in both ventricles. As compared with controls, IUGR fetuses had significantly lower early diastolic maximum velocities in the right ventricle, and recipient twins with TTTS had significantly lower systolic and early diastolic maximum velocities in both ventricles.
  
  
  CONCLUSIONS
  PT demonstrated right ventricular diastolic dysfunction in second-trimester IUGR fetuses as well as systolic and diastolic dysfunctions in both ventricles in recipient twins with TTTS. PT could be useful for evaluating fetal cardiac radial function.
authors: Department of Maternal and Fetal Medicine, Miyagi Children's Hospital, Sendai, Japan.
authors: Katsusuke
authors: K
authors: Ozawa
authors: Jun
authors: J
authors: Murotsuki
authors: Susumu
authors: S
authors: Miyashita
authors: Jin
authors: J
authors: Muromoto
authors: Hideyuki
authors: H
authors: Hasegawa
authors: Hiroshi
authors: H
authors: Kanai
authors: Nobuo
authors: N
authors: Yaegashi
mesh_terms: D004200:Diseases in Twins / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging / Q000503:physiopathology; D005318:Fetal Heart / Q000000981:diagnostic imaging* / Q000502:physiology* / Q000503:physiopathology; D005330:Fetofetal Transfusion / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D009200:Myocardial Contraction / Q000502:physiology*; D011247:Pregnancy; D016216:Ultrasonography, Prenatal / Q000379:methods*