Repetition of one or several brief episodes of ischemia renders the myocard
ium more resistant to a subsequent sustained coronary artery occlusion. The
hallmark of tills phenomenon, termed preconditioning, is infarct size limi
tation. Its mechanism is unclear but seems to involve the release of severa
l mediators, including adenosine, norepinephrine, bradykinin, endothelin-1
and the activation of protein kinase C. This cardioprotection is not limite
d to the heart but can affect many other organs. Recent evidence suggests t
hat it may also apply to the human heart, especially during cardiac surgery
, coronary angioplasty or in the clinical settings of pre-infarction angina
.