选择２０例心脏瓣膜替换术患者，随机分成极化液组和对照组。结果显示对照组再灌注后血清心肌酶、心肌丙二醛（ＭＤＡ）含量明显高于缺血前，而心肌三磷酸腺苷（ＡＴＰ）和糖原含量显著低于缺血前。极化液组再灌注后心肌ＡＴＰ、糖原、ＭＤＡ含量与缺血前比较无显著性差异，血清心肌酶释放量较对照组低。本研究显示缺血前输入极化液可防治心肌缺血一再灌注损伤。 Twenty patients with valvular heart valve replacement were selected and randomly divided into two groups: the polar fluid group and the control group. The results showed that serum myocardial enzymes and myocardial MDA levels in the control group were significantly higher than those before ischemia, while myocardial adenosine triphosphate (ATP) and glycogen contents were significantly lower than those before ischemia. The contents of ATP, glycogen and MDA in the reperfusion group were not significantly different from those before ischemia, and the levels of serum myocardial enzymes were lower than those in the control group. This study shows that the input of ischemic preconditioning can prevent myocardial ischemia-reperfusion injury.