THE CORRELATIONS BETWEEN CARDIAC
TROPONIN-T AND MYOCARDIAL FUNCTIONS IN NEWBORNS
Nacar N, Yurdakok M,
Ayabakan C, Alehan D, Oran O, Erdem G,
Tekinalp G, Yigit S,
Sarici SU
Department of
Pediatrics, Hacettepe University, Ankara, Turkey
Objective: Serum cardiac troponin-T
(cTnT) is the gold standard marker for myocardial necrosis in adults.
Cardiac dysfunction probably due to myocardial ischemia is common in
infants who are preterm and/or suffer intrauterine hypoxia. In this
prospective study, cTnT levels and echocardiographic findings were
evaluated in full-term and preterm infants with and without respiratory
distress.
Methods: There were three groups;
A: Healthy 40 full-term infants (39.4¡À1.2 w, 3354¡À467 g), B: Healthy 25
preterm infants (34.8¡À2.4 w, 2454¡À790 g) and C: 16 preterm
infants with respiratory distress syndrome or wet lung disease (30.4¡À2.6 w, 1545¡À491 g). Serum cTnT
levels (at 12th and 24th h) and echocardiographic
findings (at 24th h) were evaluated.
Results: Birth weight and cTnT
levels significantly correlated linearly with left ventricular
end-diastolic and end-systolic diameters (LVEDD and LVESD), and
controversially with ejection and shortening fractions (EF nad SF),
although there was a significant controversial correlation between birth
weight and cTnT levels (p<0.01). Serum cTnT, EF and SF measurements were
higher and, LVEDD and LVESD measurements were lower in group B than those
in group A (p<0.01). The measurements of both interventricular septum
and left ventricular posterior wall thickness in diastole and systole
(IVSD, IVSS, LVPWD and LVPWS) showed no significant difference between
groups A and B.
Group
B infants were subdivided into B1 (>34 w) and B2 (£34 w) according to their
gestational age. Serum cTnT levels were significantly higher in group C
compared to group B2 (p<0.01 and p<0.05).
Echocardiographic measurements showed no difference between these groups.
Conclusions: Serum cTnT elevation in
preterm infants may be due to subclinic or asymptomatic minor myocardial
ischemia. Normal echocardiographic findings in these infants remains to be
elucidated.