Pathophysiology of myocardial hibernation. Implications for the use of dobutamine echocardiography to identify myocardial viability

摘要

Since the pioneering works of Tennant and Wiggers, it has been known that total ischae-mia leads to a prompt cessation of contraction and eventually results in the appearance of cell damage and irreversible myocardial necrosis. Accordingly, in the minds of many cardiologists, the discovery of an abnormal regional contraction in a patient with coronary artery disease had long been equated with the presence of irreversible myocardial necrosis. However, with the advent of recanalisation treatment, evidence progressively accumulated that prolonged regional "ischaemic" dysfunction did not always arise from irreversible tissue damage and, to some extent, could be reversed by the restoration of blood flow. These observations have led to the speculation that chronically jeopardised myocardium, which is often referred to as "hibernating", could spontaneously downgrade its contractile function and minimise its energy requirements to prevent the appearance of irreversible tissue damage.