Franco K L, Uretzky G, Paolini D, Milton G, Cohn L H
J Thorac Cardiovasc Surg. 1984 Apr;87(4):561-6.
To determine whether acutely ischemic myocardium could be more effectively salvaged by reperfusion on cardiopulmonary bypass (CPB) in the cardioplegia-treated heart than with reperfusion in the beating, working heart, 52 greyhound dogs underwent 3 hours of left anterior descending (LAD) occlusion and were randomly assigned to one of four groups. In Group I (19 dogs) the LAD occlusion was released at 3 hours and reperfusion continued in the beating, working heart for an additional 3 hours. Group II (six dogs), Group III (14 dogs), and Group IV (13 dogs) were placed on CPB and underwent 45 minutes of hypothermic ischemic arrest protected by aortic root potassium cardioplegia. In Group II, only aortic root potassium cardioplegia was given; in Group III, the ischemic area was perfused with potassium cardioplegic solution via a graft from the internal mammary artery (IMA) to the LAD. In Group IV, blood cardioplegic solution via the IMA-LAD graft was used. After the cross-clamp and local occlusion were removed, CPB was discontinued after an additional 45 minutes and reperfusion was continued off CPB for an additional 1 1/2 hours (total 6 hours). The ischemic area at risk was determined by injecting monastryl blue dye via the left atrium while the LAD was briefly reoccluded. After the animal had been sacrificed and the left ventricle had been sectioned, the area of myocardial necrosis was determined by nonstaining with triphenyltetrazolium chloride (TTC). For each group, the ratios of area of necrosis/area at risk (AN/AR) were calculated and postreperfusion arrhythmias were documented. Postreperfusion arrhythmias were noted in 11 of 12 animals in the beating, working heart group and only two of 24 in the combined CPB groups. The mean AN/AR was 66% +/- 2% in the beating, working heart (Group I), 59% +/- 6% after infusion of potassium cardioplegic solution into the aortic root (Group II), 57% +/- 6% with blood cardioplegia (Group IV), and 38% +/- 6.5% after global and local application of the potassium cardioplegic solution into the ischemic area (Group III). This study suggests that the reperfused ischemic myocardium will sustain less necrosis and less postreperfusion arrhythmias when the heart is protected by global and local cold potassium cardioplegia on CPB.
为了确定在心脏停搏液处理的心脏中，通过体外循环（CPB）再灌注是否比在跳动的工作心脏中再灌注能更有效地挽救急性缺血心肌，52只灵缇犬接受了3小时的左前降支（LAD）闭塞，并被随机分为四组。在第一组（19只犬）中，3小时后松开LAD闭塞，在跳动的工作心脏中继续再灌注3小时。第二组（6只犬）、第三组（14只犬）和第四组（13只犬）接受CPB，并在主动脉根部钾心脏停搏液保护下进行45分钟的低温缺血性停搏。在第二组中，仅给予主动脉根部钾心脏停搏液；在第三组中，通过从乳内动脉（IMA）到LAD的移植物，用钾心脏停搏液灌注缺血区域。在第四组中，使用通过IMA-LAD移植物的血液心脏停搏液。在松开交叉夹和局部闭塞后，再额外进行45分钟CPB，然后停止CPB，在CPB外继续再灌注1.5小时（共6小时）。在短暂重新闭塞LAD时，通过经左心房注射莫那司蓝染料来确定有风险的缺血区域。在处死动物并将左心室切片后，通过用氯化三苯基四氮唑（TTC）不着色来确定心肌坏死区域。对于每组，计算坏死面积/有风险面积（AN/AR）的比值，并记录再灌注后心律失常情况。在跳动的工作心脏组的12只动物中有11只出现再灌注后心律失常，而在联合CPB组的24只动物中只有2只出现。在跳动的工作心脏（第一组）中，平均AN/AR为66%±2%，在向主动脉根部注入钾心脏停搏液后（第二组）为59%±6%，在使用血液心脏停搏液时（第四组）为57%±6%，在向缺血区域全身和局部应用钾心脏停搏液后（第三组）为38%±6.5%。这项研究表明，当心脏在CPB上通过全身和局部冷钾心脏停搏液进行保护时，再灌注的缺血心肌将遭受更少的坏死和更少的再灌注后心律失常。
