Myocardial hibernation: a delicate balance.
The pathophysiology of myocardial hibernation is characterized as a situation of reduced regional contractile function distal to a coronary artery stenosis that recovers after removal of the coronary stenosis. A subacute "downregulation" of contractile function in response to reduced regional myocardial blood flow exists, which normalizes regional energy and substrate metabolism but does not persist for more than 12-24 h. Chronic hibernation develops in response to one or more episodes of myocardial ischemia-reperfusion, possibly progressing from repetitive stunning with normal blood flow to hibernation with reduced blood flow. An upregulation of a protective gene program is seen in hibernating myocardium, putting it into the context of preconditioning. The morphology of hibernating myocardium is characterized by both adaptive and degenerative features.
Heusch
Gerd
G
Institut für Pathophysiologie, Zentrum für Innere Medizin, Universitätsklinikum Essen, Hufelandstr. 55, 45122 Essen, Germany. gerd.heusch@uni-essen.de
Schulz
Rainer
R
Rahimtoola
Shahbudin H
SH
D000818:Animals; D003326:Coronary Circulation / Q000502:physiology*; D006801:Humans; D009200:Myocardial Contraction / Q000502:physiology*; D017682:Myocardial Stunning / Q000473:pathology* / Q000503:physiopathology*