[Irreversible ischemic myocardial damage. Physiopathologic aspects of ischemia and myocardial revascularization].

A substantial amount of research has been focused on the mechanism of irreversible ischemic cellular damage. An irreversibly damaged cell cannot restore normal function when reperfused. During ischemia the cellular level of high energy phosphates decreases, which induces a rise in the cytosolic level of free calcium. An elevated level of cytosolic calcium is probably harmful to the myocyte, partly because calcium activates proteases and phospholipases. Reperfusion of an ischemic myocyte disturbs cellular ion control, increases cellular volume, induces mechanical stress on cellular membranes and produces free oxygen radicals. Thus, the cause of irreversible injury during ischemia and reperfusion probably includes several factors. Knowledge about these mechanisms will hopefully provide new therapeutic options.