title: Cardiac troponin T as a biochemical marker of cardiac dysfunction and ductus venosus Doppler velocimetry.
abstract: OBJECTIVE
  The aim of this study was to determine the correlation between ductus venosus (DV) Doppler velocimetry and fetal cardiac troponin T (cTnT).
  
  
  METHODS
  Between March 2007 and March 2008, 89 high-risk pregnancies were prospectively studied. All patients delivered by cesarean section and the Doppler exams were performed on the same day. Multiple regression included the following variables: maternal age, parity, hypertension, diabetes, gestational age at delivery, umbilical artery (UA) S/D ratio, diagnosis of absent or reversed end-diastolic flow velocity (AREDV) in the UA, middle cerebral artery (MCA) pulsatility index (PI), and DV pulsatility index for veins (PIV). Immediately after delivery, UA blood samples were obtained for the measurement of pH and cTnT levels. Statistical analysis included the Kruskal-Wallis test and multiple regressions.
  
  
  RESULTS
  The results showed a cTnT concentration at birth >0.05 ng/ml in nine (81.8%) of AREDV cases, a proportion significantly higher than that observed in normal UA S/D ratio and UA S/D ratio >p95 with positive diastolic blood flow (7.7 and 23.1%, respectively, p<0.001). A positive correlation was found between abnormal DV-PIV and elevated cTnT levels in the UA. Multiple regression identified DV-PIV and a diagnosis of AREDV as independent factors associated with abnormal fetal cTnT levels (p<0.0001, F(2.86)=63.5, R=0.7722).
  
  
  CONCLUSIONS
  DV-PIV was significantly correlated with fetal cTnT concentrations at delivery. AREDV and abnormal DV flow represent severe cardiac compromise, with increased systemic venous pressure, and a rise in right ventricular afterload, demonstrated by myocardial damage and elevated fetal cTnT.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, University of São Paulo, Brazil. roseli.nomura@terra.com.br
authors.forename: Roseli Mieko Yamamoto
authors.initials: RM
authors.lastname: Nomura
authors.forename: Fábio Roberto
authors.initials: FR
authors.lastname: Cabar
authors.forename: Verbênia Nunes
authors.initials: VN
authors.lastname: Costa
authors.forename: Seizo
authors.initials: S
authors.lastname: Miyadahira
authors.forename: Marcelo
authors.initials: M
authors.lastname: Zugaib
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001783:Blood Flow Velocity / Q000502:physiology; D003430:Cross-Sectional Studies; D005260:Female; D005333:Fetus / Q000098:blood supply*; D006321:Heart / Q000503:physiopathology*; D006801:Humans; D007231:Infant, Newborn; D017078:Laser-Doppler Flowmetry; D020768:Middle Cerebral Artery / Q000503:physiopathology; D010927:Placental Insufficiency / Q000503:physiopathology; D011247:Pregnancy; D011446:Prospective Studies; D020107:Troponin T / Q000097:blood*; D014469:Umbilical Arteries / Q000503:physiopathology*; D014471:Umbilical Veins / Q000503:physiopathology*
chemical_list: D015415:Biomarkers; D020107:Troponin T