Summary
Reperfusion injury may cause myocardial cell death and limit the benefit achieved
by restoration of coronary artery patency in patients with acute myocardial infarction.
The mechanism includes altered Ca2+ handling with cytosolic and mitochondrial Ca2+ overload, Ca2+- and ATP-dependent hypercontraction, cytoskeletal fragility, mitochondrial permeability
transition and gap junction-mediated propagation of cell death, as well as alterations
in non-cardiomyocyte cells, in particular platelets and endothelial cells. cGMP modulates
favorably all these mechanism, mainly through PKG-mediated actions, but cGMP synthesis
is altered in reperfused cardiomyocytes and endothelial cells by mechanisms that are
only partially understood. Stimulation of cGMP synthesis during initial reperfusion
by means of natriuretic peptides has been found protective in different animal models
and in patients. Moreover, increasing evidence indicates that cGMP is an important
step in signal transduction of endogenous cardioprotection. Thus, the cGMP pathway
appears as a key element in the pathophysiology of myocardial ischaemiareperfusion
and as a promising therapeutic target in patients with acute myocardial infarction.
Keywords
Ischaemic heart disease - platelet physiology - acute myocardial infarction