低温缺血期间新生儿心肌的保护。心脏停搏液对兔左心室功能的影响。

Protection of the neonatal myocardium during hypothermic ischemia. Effect of cardioplegia on left ventricular function in the rabbit.

作者信息

Bove E L, Stammers A H, Gallagher K P

出版信息

J Thorac Cardiovasc Surg. 1987 Jul;94(1):115-23.

Abstract

The protective effect of cardioplegia upon neonatal myocardium during ischemia has not been clearly established. This study evaluated the effects of cardioplegia on left ventricular function in isolated working neonatal rabbit hearts (aged 1 week) subjected to 120 minutes of global ischemia at 28 degrees C. Four groups were studied: Group 1, hypothermia alone; Group 2, intermittent washout with an oxygenated noncardioplegic solution; Group 3, multidose cardioplegia; Group 4, single-dose cardioplegia. After ischemia, cardiac output was reduced to 72% +/- 5% (mean +/- standard error of the mean) of control (p less than 0.02) in Group 1 and to 56% +/- 4% in Group 2 (p less than 0.001). In contrast, there was no significant reduction from baseline cardiac output in those animals receiving cardioplegic solution (Group 3, 93% +/- 6%, and Group 4, 97% +/- 4%). Group 2 hearts demonstrated significantly worse recovery of cardiac output and stroke volume than all other groups. After ischemia, the first derivative of left ventricular pressure fell to 73% +/- 13% of control in Group 1 (p less than 0.1) and to 89% +/- 5% in Group 2 (p less than 0.05). However, the first derivative of left ventricular pressure was restored to control values in Group 3 (118% +/- 11%) and Group 4 (114% +/- 9%). When compared to baseline, creatine kinase was higher 30 minutes after reperfusion in Group 1 (40 +/- 8 versus 143 +/- 32 IU/L/gm, p less than 0.05) and in Group 2 (39 +/- 7 versus 163 +/- 33 IU/L/gm, p less than 0.05). Creatine kinase remained unchanged from baseline in Groups 3 and 4. This study demonstrates excellent preservation of left ventricular function in the neonatal rabbit heart protected with cardioplegic solution. In contrast, neither hypothermia alone nor intermittent washout with an oxygenated noncardioplegic solution was effective in preventing myocardial dysfunction. As in adults, the administration of cardioplegic solution preserves ventricular function during ischemia in neonatal hearts.

摘要

心脏停搏液对新生儿心肌在缺血期间的保护作用尚未明确确立。本研究评估了心脏停搏液对在28℃下经历120分钟全心缺血的离体工作新生兔心脏（1周龄）左心室功能的影响。研究了四组：第1组，单纯低温；第2组，用含氧非心脏停搏液间歇性冲洗；第3组，多剂量心脏停搏液；第4组，单剂量心脏停搏液。缺血后，第1组的心输出量降至对照组的72%±5%（平均值±平均标准误差）（p<0.02），第2组降至56%±4%（p<0.001）。相比之下，接受心脏停搏液的动物（第3组，93%±6%，第4组，97%±4%）的心输出量与基线相比无显著降低。第2组心脏的心输出量和每搏量恢复情况明显比所有其他组差。缺血后，第1组左心室压力的一阶导数降至对照组的73%±13%（p<0.1），第2组降至89%±5%（p<0.05）。然而，第3组（118%±11%）和第4组（114%±9%）左心室压力的一阶导数恢复到了对照值。与基线相比，再灌注30分钟后第1组（40±8对143±32 IU/L/gm，p<0.05）和第2组（39±7对163±33 IU/L/gm，p<0.05）的肌酸激酶升高。第3组和第4组的肌酸激酶与基线相比保持不变。本研究表明，用心脏停搏液保护的新生兔心脏左心室功能得到了良好的保存。相比之下，单纯低温或用含氧非心脏停搏液间歇性冲洗在预防心肌功能障碍方面均无效。与成人一样，心脏停搏液的应用可在新生儿心脏缺血期间保存心室功能。