Non-ischemic heart preconditioning.

Ischemic heart conditioning has been shown to protect the organ against ischemia/reperfusion injury. Animal studies have revealed that the heart can also be conditioned by non-ischemic procedures, namely physical exercise and tachycardia. Long and short term endurance training, sprint training, resistance or interval training and even one bout of exercise induce cardiac preconditioning, which is manifested by a reduction in post ischemia/reperfusion infarct size, ventricular arrhythmia and improved heart function. Several factors contribute to the exercise-induced heart preconditioning, among which the most important can be: increased activity of the anti-radical defense system, opioids, interleukin-6, nitric oxide, ATP dependent potassium channels, heat shock protein 72 and sphingosine-1-phosphate. A few studies have also shown that one bout of exercise in patients with stable angina increases tolerated workload. According to some data obtained in swine and dogs, stimulated tachycardia before ischemia/reperfusion reduces the infarct size. Future studies are needed to fully clarify the mechanisms responsible for exercise- or tachycardia-induced heart preconditioning against ischemia/reperfusion. It may lead to the development of new treatment modes of the disease.