New Paradigms of Coronary Artery Disease

Hibernation, Stunning, Ischemic Preconditioning

Detailed analyses of regional myocardial blood flow, function, metabolism and morphology in ischemic and reperfused myocardium have led to the identifi­ cation of important phenomena, i. e. , myocardial hibernation, myocardial stun­ ning and ischemic preconditioning. Both the hibernating and the stunned myocardium characterize viable though dysfunctional as distinguished from necrotic tissue. With the advent of reperfusion procedures, the distinction between reversibly injured, hypofunctional myocardium from irreversibly injured, hypofunctional myocardium is of utmost clinical importance. The pathophysiological distinction of hibernating and stunned myocardium is con­ troversial, but reperfusion is mandatory anyway. Ischemic preconditioning is the most powerful maneuver known so far to delay infarct development. Its clinical significance has been suggested from retrospective analyses of data from patients suffering a myocardial infarction as well as from controlled PTCA studies. Whether or not preconditioning can be achieved pharmacologically in the clinical setting remains to be established. The mechanisms and signal cascade underlying myocardial hibernation, myocardial stunning and ischemic preconditioning are not clear in detail. Over the last year, focussed issues on myocardial hibernation, myocardial stunning and ischemic preconditioning were published in Basic Research in Car­ diology; they have received great interest and a good response. Therefore, these focussed issues are now combined and published as a separate monograph. We express our gratitude once more to all our colleagues who contributed to this monograph, to Ms. Ibkendanz of Steinkopff, and to Ms. Philipp and Mr. Heinrichs from Bayer AG Germany, who supported this additional publication.