窒息新生儿心肌损害的动物实验和临床多指标研究

Study on multiple indicators to evaluate myocardial injury in asphyxic newborns

目的 通过临床检测及动物实验探讨心肌酶谱、肌钙蛋白、心功能等多指标对新生儿窒息引起的心肌损害的临床综合诊断价值、敏感性及内在联系。方法将2001年6月一2002年10月住院的30例窒息新生儿分为轻度窒息组、重度窒息组、重度窒息恢复期组,选正常分娩的足月新生儿共30例为正常对照组,分别测心肌酶谱及同工酶、心肌肌钙蛋白T(CTnT),做心电图及测心率,通过心脏超声心动图观察心脏结构和测量心功能。动物实验观察出生3 d的大鼠在不同时间缺氧后心肌细胞的搏动次数、心肌酶变化及心肌细胞微细结构的变化。结果重度窒息组心率显著减慢,心肌酶谱指标均明显升高,CTnT阳性率高。心功能指标均明显下降,A/E倒置;轻度窒息组LDH、CK、CK-MB及HBDH轻度升高,心功能中仅FS和SV轻度下降;重度窒息恢复期组各项指标均恢复正常;各组窒息新生儿心脏结构无明显改变。大鼠缺氧时间越长心肌酶指标升高越明显,心肌细胞搏动越慢,心肌细胞微细结构发生改变。结论 心脏超声心动图对窒息新生儿心肌损害的判断具有重要价值,FS和SV可以作为早期心肌损害的指标;心肌酶谱及同工酶可早期诊断窒息所致的心肌损害、判断严重程度及评估恢复情况;肌钙蛋白对反映心肌损害的敏感性并不高于心肌酶学指标;综合分析CK—MB>40.76或CTnT阳性,EF、FS?

Objective To study the value of multiple indicatiors in evaluating myocardial injury in asphyxic newborn. Methods Multiple indicators were measured in 20 slightly asphyxic neonates, 10 severely asphyxic newborns both in their acute period and their recovery period, and 30 control neonates. Multiple indicators were also measured in Wistar rats. Results Heart rates, AST, CK, CK-MB, LDH, HBDH, CTnT, FS, CI, EF, SV of severely asphyxic newborn changed significantly compared with others; Nearly all A/E in severely group were more than 1 ;Only LDH,CK,CK-MB, HBDH, FS and SV in slightly asphyxic neonates changed slightly compared with controls.The results of determination in rats were as same as those of clinic determination. Electron microscope showed great changes in microstructure of cardiac muscle cells. Conclusions Myocardial enzymes and CTnT are useful to the diagnosis and convalescences of myocardial injury and FS, SV can help the prediction of myocardial injury after asphyxia.