[Stunning, hibernation, and heart failure in patients with coronary disease: crucial role of impaired coronary flow reserve]. FT Stunning, hibernation ed insufficienza cardiaca nei pazienti con malattia coronarica: il ruolo centrale di una ridotta riserva coronarica.

Hibernating myocardium can be defined as a chronic, but reversible left ventricular dysfunction that may contribute to congestive heart failure in patients with coronary artery disease. The dysfunction can improve after coronary revascularization and therefore its identification and treatment become central in the management of patients with heart failure secondary to coronary artery disease. Hibernating myocardium can be detected by several techniques (echocardiography performed during the infusion of dobutamine, single photon and positron emission tomography-PET, and magnetic resonance imaging), but none of these techniques can be considered unequivocally superior to the others for the identification of hibernating myocardium. As PET technology has advanced, the noninvasive quantification of absolute regional myocardial blood flow has become possible. The measurement of myocardial blood flow by PET has contributed to the demonstration that transmural blood flow in hibernating muscle is generally within the normal range while the coronary flow reserve is invariably and severely impaired. These findings have contributed to a new pathophysiological theory of hibernation where repetitive ischemia and stunning are considered as the initial mechanisms that might start the process of myocardial hibernation.