Amniotic fluid cardiac troponin T in pathological pregnancies with evidence of chronic fetal hypoxia.
OBJECTIVE
To determine if prenatally measured cardiac troponin T in the amniotic fluid (Am-TnT) could be used as a marker of fetal myocardial hypoxia and necrosis in pathological pregnancy characterized by increased concentration of amniotic fluid erythropoietin (Am-EPO) as a sign of chronic fetal hypoxia.


METHODS
We measured Am-TnT and Am-EPO in 29 pathological and 5 uncomplicated pregnancies. Samples of amniotic fluid were collected prospectively during elective amniocentesis (n=15), cesarean sections (n=17), and before elective induction of labor in two pregnancies with stillbirth. Am-TnT and Am-EPO were determined by chemiluminescent immunological method.


RESULTS
Am-TnT was undetectable in normal pregnancies, but it was detectable in 9 of 29 amniotic fluid samples from pathological pregnancies, with a median value of 0.030 microg/L (range, 0.010-111.6 microg/L). Am-EPO values were above normal values (>11 U/L) in all pathological pregnancies. Am-EPO concentration showed positive correlation with the Am-TnT concentration (r=0.526, P=0.003). Median concentration of Am-EPO in 9 pregnancies with detectable Am-TnT was 198 U/L (range, 16-3,378 U/L). In 20 pathologic pregnancies with undetectable Am-TnT, the median concentration of Am-EPO was 39 U/L (range, 12-293 U/L). There was no statistically significant difference between the groups (P=0.051).


CONCLUSIONS
Am-TnT is measurable in some pathological pregnancies with signs of fetal chronic hypoxia and myocardial involvement and could be potentially used as a biochemical marker of fetal myocardial injury.
Stefanovic
Vedran
V
Department of Obstetrics and Gynecology, Helsinki University Central Hospital, Haartmaninkatu 2, 00290 Helsinki, Finland. vedran.stefanovic@hus.fi
Loukovaara
Mikko
M
D000649:Amniocentesis; D000653:Amniotic Fluid / Q000737:chemistry*; D015415:Biomarkers; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis / Q000473:pathology*; D016022:Case-Control Studies; D002908:Chronic Disease; D004921:Erythropoietin / Q000032:analysis*; D005260:Female; D005317:Fetal Growth Retardation / Q000503:physiopathology; D005311:Fetal Hypoxia / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D020107:Troponin T / Q000032:analysis*
D015415:Biomarkers; D020107:Troponin T; D004921:Erythropoietin