Myocardial ischemia: basic concepts, diagnosis and clinical implications. Part two

Myocardial ischemia can be irreversible or reversible depending on multiple molecular and physiological factors. In irreversible myocardial ischemia there are three types of cell death on a myocardial level: necrosis, apoptosis and autophagy; whereas in reversible ischemia the restoration of the myocytes is determined by factors such as early recovery of coronary blood flow and pre- and postischemic conditioning phenomena. Concepts such as stunned myocardium (temporary mechanical dysfunction following an ischemic episode but with normal blood flow and without irreversible damage) and hibernating myocardium (viable myocardial region without contractility) are quiescent forms of the cardiac function and explain the ability of the myocardium to resume its normal functioning after an ischemic episode.