The Change Of Glycogen Phosphorylase Isoenzyme BB In Neonates With Asphyxia Complicated With Myocardial Injury

Objective Hypoxic-ischemic myocardial (HIM) is the serious complications after perinatal asphyxia. The study of glycogen phosphorylase isoenzyme BB (GPBB) indicates that it may be sensitive biomarker in myocardial injury, but its use in neonates has not been very well studied. To further investigate the change of GPBB in neonates with asphyxia complicated with myocardial injury,we study the level of GPBB in neonates with asphyxia, and analyze its correlation with various perinatal factors in this experiment, in order to provide theoretical evidence for early diagnosis and management in clinical.Methods 64 neonates with asphyxia (including 39 mild asphyxia,25 severe asphyxiated neonates,30 neonates with and 34 without myocardial injury) were enrolled and 25 neonates without asphyxia and myocardial disease were studied as control. The plasma levels of CPBB were measured by enzyme-linked immunosorbent assay (ELISA), myocardial enzymes, cardiac troponin I, electrocardiogram, chest X-ray were performed simultaneously.Results 1. The plasma CPBB levels were significantly higher in neonates with myocardial injury(13.84,7.57)ng/ml than those without myocardial injury(4.97,3.24) ng/ml and control group (4.95,1.99) ng/ml (P<0.01), with no significant difference between non-myocardial injury and the control group (P>0.05).2. The sensitivities of GPBB, cTnI and CK-MB in diagnosing myocardial injury were 90%,66.7%, 83.3% respectively. The sensitivity of GPBB was significantly higher than that of cTnI (χ2=4.812,P<0.05), with no statistical difference between GPBB and CK-MB =0.577, P>0.05). The specificities of GPBB, cTnI and CK-MB in diagnosing myocardial injury were 88.2%,91.2%,67.6% respectively. The specificity of GPBB was significantly higher than that of CK-MB(χ2=4.191,P<0.05), with no statistical difference between GPBB and cTnI(χ2=0.159, P>0.05).3. Plasma GPBB levels were significantly higher in neonates with severe asphyxia (14.67,6.09) ng/ml than those with mild asphyxia (5.61,3.56) ng/ml and control group (4.95,1.99) ng/ml (P<0.01). GPBB levels were higher in mildly asphyxiated neonates than those in control neonates, but with no statistical significance (P>0.05).4. Spearman rank correlation analysis showed that plasma GPBB levels positively correlated with the cloudiness of the amniotic fluid (r=0.500,P<0.001) and negatively correlated with Apgar score (r=-0.520,P<0.001)Conclusions The GPBB levels were significantly increased in neonates with myocardial ischemia injury, moreover GPBB levels were strongly related with the degree of asphyxia, the severer the degree of asphyxia, the higher the level of GPBB. There was a correlation between the plasma GPBB and amniotic fluid, and also Apgar score, suggesting that there have relation between the severity of intrauterine hypoxia or perinatal asphyxia and hypoxic-ischemic myocardial injury of neonates. These results demonstrate that the determination of plasma GPBB in neonates with asphyxia can early detect myocardial injury and is useful in evaluating the severity of myocardial injury and asphyxia, which provide guidance for early diagnosis and treatment of the disease.