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

Abstract

ABSTRACTBackground: 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.