门冬氨酸钾镁在冠状动脉旁路移植术中对心肌的保护作用

目的研究在体外循环（extracorporeal circulation,ECC）下行冠状动脉旁路移植术（coronary artery bypassgraft,CABG）中应用门冬氨酸钾镁（potassium magnesium aspartate,PMA）对缺血心肌的保护作用。方法将40例CABG患者随机分成两组（n=20）,心肌保护液的温度均为4℃ A组：停跳液中加入50ml PMA替代常规停跳液中的部分氯化钾,维持心肌保护液中的K＋浓度为18 mmol/L,Mg2＋浓度为8 mmol/L B组：应用常规的阜外医院冷血停跳液配方,心肌保护液中的K＋浓度为28 mmol/L,Mg2＋浓度为4 mmol/L。监测所有患者的临床效果和术后心律失常的发生率 并在诱导前、ECC后、术后6 h、24 h、72 h和术后6 d间断监测心肌肌钙蛋白I（cTnI）和肌酸激酶同工酶（CKMB）的水平。结果A组的自动复跳率明显高于B组（P〈0.05） 两组cTnI和CKMB水平从术后6 h开始升高（P〈0.05）,在术后24-72 h达到峰值,在术后第6天恢复。A组术后6 h、24 h和72 h的血浆cTnI和CKMB水平较B组明显降低（P〈0.01）,且在脱离ECC后心律失常的发生率较B组明显降低（P〈0.05）。结论CABG中应用PMA有利于缺血心肌的保护并可降低术后心律失常的发生率。

The Protective Effect of Potassium Magnesium Aspartate on Myocardium during Coronary Artery Bypass Graft

OBJECTIVE To investigate whether the supplement of potassium magnesium aspartate （PMA） to cardioplegic solutions improves myocardial protection during coronary artery bypass graft （CABG） . METHODS Forty patients underwent CABG were divided into two groups randomly （ n = 20） ： group A and group B, and the temperature of cardioplegia was maintained to 4℃. The cardioplegia in group A was added with 50ml PMA and the level of potassium and magnesium were maintained around 18mmoL/L and 8mmoL/L,respectively. Patients in group B received routine cool blood cardioplegia, and the level of potassium and magnesium were maintained around 28mmol/L and 4mmol/L,respectively. The effect of myocardium protection in these two groups was evaluated by clinical outcome, the differences of cTnI and CKMB. Serial venous blood samples were obtained before induction, after extracorporeal circulation （ECC）, postoperative 6 h,24h,72h and 6th day,respectively. RFSULTS The rate of re - heating in group A was higher than that in group B （ P 〈0.05）. The plasma cTnI and CKMB level of two groups increased at postoperative 6h（ P 〈0.05） ,reached peak at postoperative 24h -72h and recovered at postoperative 6th day. Compared to group B,the plasma concentration of cTnI and CKMB in group A were significantly lower at postoperative 6h,24h and 72h （ P 〈0.01 ）. CONCLUSION The supplement of PMA to cardioplegic solutions can provide more myocardium protective effect for CABG patients.