To
obtain a bloodless operating field during open-heart surgery, aortic
cross-clamping is deliberately introduced leading to a period of myocardial
ischemia. As a consequence, an unbalance between demand and supply of cellular
high-energy phosphates is created. This results in a rapid fall of creatine
phosphate levels, followed by a decrease in the tissue content of ATP. Low
levels of ATP are related to the loss of cellular function and the onset of
cell injury and death. The precise mechanism of action is, however, still
unclear. Most protective measures taken during open-heart surgery aimed at the
conservation of cardiac high-energy phosphate pools in the ischemic tissues.
To
this end, commonly electro-mechanical activity is abolished rapidly by
intracoronary infusion of an ice-cold crystalloid or sanguineous cardioplegic
solution immediately after aortic crossclamping. The clinical application of
creatine phosphate (PCr) for cardioprotection during heart surgery and
myocardial ischaemia is based on the results of a series of pharmacological
studies in animal models. Its application as a cardioplegic additive and for
intravenous infusion leads to significantly better functional recovery following
ischaemia, during the postinfarction period and upon reperfusion. Read more>>>>>>>>>>>
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