Myocardial dysfunction as a predictor of the severity and mortality of hypoxic ischaemic encephalopathy in severe perinatal asphyxia: a case-control study.

Background

In perinatal asphyxia, hypoxia often leads to myocardial ischaemia. Few studies have assessed the degree of myocardial dysfunction in severely asphyxiated term neonates. Aim: To assess the extent of myocardial damage in newborns with severe perinatal asphyxia.

Methods

A case-control study was conducted in asphyxiated newborns with hypoxic ischaemic encephalopathy (HIE) and in controls who were term non-asphyxiated newborns. Total (T) creatinine kinase (CK), CK-MB, troponin-T and 12-lead electrocardiography (ECG) and echocardiography were performed in both groups within 24-48 h after birth. The proportions of asphyxiated neonates with myocardial dysfunction and its relationship between severity of HIE and immediate outcome was compared.

Results

Five of 23 asphyxiated neonates developed stage I, 10 stage II and eight stage III HIE. Serum levels of CK-T and CK-MB were raised in all 23 cases and troponin-T was raised in 13 (56.5%) HIE cases. ECG was abnormal in all cases and echocardiography in three (13%). Left ventricular ejection fraction (LVEF) and right ventricular ejection fraction (RVEF) were significantly decreased in all asphyxiated neonates. Eight (35%) patients died. Enzyme levels were higher and ECG and echocardiography abnormalities were common in infants with more severe HIE (p <0.05). Mean serum levels of CK-T and MB (p <0.001) and troponin-T (p =0.002) were higher in non-survivors. Mean LVEF and RVEF values were higher in survivors (p <0.001). All the controls had normal enzyme levels and echocardiography. ECG was abnormal in one control.

Conclusion

Cardiac enzymes, ECG and echocardiography changes were associated with increasing severity of HIE and mortality.