目的 探讨早产儿动脉导管未闭(patent ductus arteriosus,PDA)对早产儿心肌的影响.方法 选择2010年5月1日至2011年1月31日入院治疗的110例胎龄28~36周的早产儿,在生后72 h和7d取血,测定血清肌钙蛋白T(cardiac troponin T,cTnT)和肌酸激酶MB同工酶(creatine kinase MB isoenzyme,CK-MB)水平,并行心脏超声心动图检查.根据超声心动图结果分为PDA组(44例)和对照组(66例).PDA组患儿接受布洛芬治疗后,再次行超声心动图检查,同时2组复查相关的血清学指标.统计学方法采用t或近似t检验、x2检验、多元线性回归和Spearman秩相关检验.结果 治疗前,PDA组的血清cTnT和CK-MB均高于对照组[(0.259±0.134)μg/L与(0.083±0.054)μg/L,t=9.557,P<0.01;(7.31±2.69)μg/L与(5.71±1.88)μg/L,t=2.588,P<0.05].治疗成功的34例PDA患儿cTnT和CK-MB较治疗前显著降低,分别降至(0.062±0.039)μg/L和(5.34±1.50)μg/L(t分别为9.268和5.974,P<0.05);但与对照组cTnT、CK-MB相比差异均无统计学意义(P>0.05).治疗失败的10例PDA患儿cTnT、CK-MB水平较治疗前稍有降低[分别为(0.193±0.049)μg/L和(6.93±1.63)μg/L,t分别为1.525和0.766,P均>0.05],但仍明显高于对照组(t分别为9.068和4.055,P<0.05).cTnT水平与机械通气时间、PDA、肺透明膜病呈正相关,不受性别、胎龄、体重的影响;而CK-MB与性别、胎龄、体重、机械通气时间及PDA均显著相关.在PDA组,cTnT水平与动脉导管直径呈正相关;而CK-MB与各项超声心动图指标均不相关.结论 有临床表现的PDA可造成早产儿心肌损伤,cTnT和CK-MB的动态变化与PDA病情程度相平行,动态监测cTnT和CK-MB有助于PDA并发心肌损伤的早期诊断和及时干预.
Objective To investigate the effect of patent ductus arteriosus(PDA)on myocardial injury of premature infants.Methods From May 1,2010 to January 31,2011,110 preterm infants with gestational age from 28 to 36 weeks accepted echocardiography examination,and their blood samples were collected to determine cardiac troponin T(cTnT)and creatine kinase MB isoenzyme (CK-MB)levels 72 h and 3 d after deliveries.All subjects were divided into two groups according to the echocardiogram results:PDA group(n=44)and control group(n=66).The infants with PDA were treated with ibuprofen,and then echocardiography was taken again.cTnT and CK-MB were re-measured in both groups.Chi-square test,t-test,multi-variate linear regression and Spearman rank correlation test were perfomed for statistical analysis.Results Before treatment,cTnT[(0.259±0.134)μg/L]and CK-MB[(7.31± 2.69)μg/L]level of PDA group were significantly higher than those[(0.083±0.054)μg/L and(5.71±1.88)μg/L]of control group(t=9.557 and 2.588,P<0.01 and <0.05,respectively).For 34 infants with successful treatment,cTnT and CK-MB levels decreased markedly to(0.062 ± 0.039)μg/L and(5.34 ± 1.50)μg/L,respectively(t =9.268 and 5.974,all P<0.05),compared with those levels before treatment.For the ten infants failed to close ductus,the cTnT and CK-MB levels[(0.193±0.049)μg/L and(6.93±1.63)μg/L,respectively],were lower than those before treatment(t=1.525 and 0.766,all P>0.05),while higher than those of the control group(t=9.068 and 4.055,P<0.05).Level of cTnT positively related to the duration of ventilation,PDA and respiratory distress syndrome,while did not relate to gender,gestational age and birth weight.CK-MB level was associated to gender,gestational age,birth weight,duration of ventilatory support and PDA.In PDA group,the cTnT level was positively related to the diameter of the ductus,but not related to any indicators in echocardiography.Conclusions Symptomatic PDA could cause myocardial injury in preterm infants.The changes of blood cTnT and CK-MB were consistent with the severity of PDA.Serial measurements of blood cTnT and CK-MB might help to make early diagnosis and treatment for premature infants with PDA and myocardial injury.