Echocardiographic screening for myocardial dysfunction among asphyxiated newborns

Background: Perinatal asphyxia/ischemia is an interruption in the availability of oxygen supply to the myocardium. We sought to assess myocardial function among asphyxiated and non-asphyxiated neonates using echocardiography. Methods: The present case-control study was undertaken at the neonatal intensive care unit (NICU) of a tertiary care hospital. Neonates with asphyxia who were admitted to the NICU were included in the study. The diagnosis of asphyxia was established on the basis of the APGAR score at 1 and 5 minutes. Myocardial function was assessed in terms of serum cardiac troponin I (CTnI) and different echocardiographic parameters such as M-Mode, Doppler flow parameters, and tissue Doppler imaging. Results: Thirty asphyxiated (the case group) and 30 non-asphyxiated (the control group) term neonates were enrolled in the study. The asphyxia group had significantly lower (P < 0.001) 1- and 5-minute APGAR scores than the controls. The asphyxia group had a higher serum CTnI value. The differences between the 2 groups concerning M-Mode parameters in the first 12 hours of life were statistically significant (P < 0.001). The case and control groups were also statistically significantly different regarding left atrial pressure at 48 hours following birth, calculated as a ratio of E/e’ (P < 0.001). The differences between the 2 study groups at 24 hours after birth as regards tissue Doppler parameters, including left ventricular ejection time and left ventricular Tei index, were also statistically significant (P < 0.001). The case and control groups also showed statistically meaningful differences concerning right ventricular ejection period/ ejection time at 24 hours after birth (P < 0.002). Conclusions: It can be concluded that the myocardial function assessment using CTnI and different echocardiographic techniques is the most sensitive and specific method in the detection of ischemic cardiac injury in asphyxiated newborns.