Tomai F, Crea F, Chiariello L, Gioffrè P A
Divisione di Cardiochirurgia, Università di Roma Tor Vergata, European Hospital and Istituto di Cardiologia (F.C.), Università Cattolica del Sacro Cuore, Rome, Italy.
Circulation. 1999 Aug 3;100(5):559-63. doi: 10.1161/01.cir.100.5.559.
Ischemic preconditioning, a powerful form of endogenous protection against myocardial infarction, has been demonstrated in several animal species and, recently, in isolated human cardiomyocytes. For both logistic and ethical reasons, no clinical study can meet the strict conditions of experimental studies on preconditioning with infarct size as the end-point. Nevertheless, the demonstration of adaptation to ischemia observed during in vitro studies on human atrial trabeculae, in patients in the setting of coronary bypass surgery, and in the setting of coronary angioplasty in the absence of collateral vessel recruitment strongly suggests that ischemic preconditioning occurs in humans. This notion is further supported by the observation that in these human models, the adaptation to ischemia is influenced by drugs acting on K(ATP) channels and on purinergic and alpha-adrenergic receptors, similar to what is observed in accepted experimental models of ischemic preconditioning. This important form of myocardial endogenous protection may also play a role in the warm-up phenomenon and in mediating the beneficial effects of preinfarction angina. The demonstration of ischemic preconditioning in humans and the identification of some of its mediators suggests that in patients at high risk for myocardial infarction, drugs known to block this endogenous form of protection should be used with caution, whereas drugs known to elicit preconditioning might have a relevant therapeutic role.
缺血预处理是一种针对心肌梗死的强大内源性保护形式，已在多种动物物种中得到证实，最近在分离的人类心肌细胞中也得到了证实。出于逻辑和伦理原因，没有任何临床研究能够满足以梗死面积为终点的预处理实验研究的严格条件。然而，在对人类心房小梁的体外研究、冠状动脉搭桥手术患者以及无侧支血管募集的冠状动脉成形术患者中观察到的对缺血的适应性表现，有力地表明人类也会发生缺血预处理。在这些人体模型中，对缺血的适应性受作用于K（ATP）通道、嘌呤能和α-肾上腺素能受体的药物影响，这一观察结果进一步支持了这一观点，类似于在公认的缺血预处理实验模型中所观察到的情况。这种重要的心肌内源性保护形式可能在热身现象以及介导梗死前心绞痛的有益作用中也发挥作用。人类缺血预处理的证实及其一些介导因子的确定表明，对于心肌梗死高危患者，已知会阻断这种内源性保护形式的药物应谨慎使用，而已知能引发预处理的药物可能具有相关治疗作用。
