G. Steurer et al., ACUTE MYOCARDIAL-INFARCTION, REPERFUSION INJURY, AND INTRAVENOUS MAGNESIUM THERAPY - BASIC CONCEPTS AND CLINICAL IMPLICATIONS, The American heart journal, 132(2), 1996, pp. 478-482
The concept of reperfusion-induced injury has aroused special interest
during the past decade as thrombolysis and direct angioplasty were in
troduced for early restoration of coronary blood flow in patients with
acute myocardial infarction. There is experimental and clinical evide
nce that oxygen-derived free radicals (oxyradical hypothesis), activat
ion of the complement system (complement hypothesis), and disturbance
in calcium homeostasis (calcium hypothesis) may account for the develo
pment of reperfusion injury. Data from numerous animal experiments and
clinical trials suggest that magnesium, a physiologic calcium blocker
, may be efficacious for reduction of reperfusion injury. Despite enco
uraging results from previous clinical trials that revealed beneficial
effects of intravenous magnesium therapy with respect to mortality, l
eft ventricular function, and infarct size, a recently published large
-scale trial (ISIS-4) provided conflicting data and caused major contr
oversy. Further clinical trials, well-designed and carefully conducted
, should elucidate the beneficial effects of magnesium in acute myocar
dial infarction, especially in conjunction with new and aggressive rep
erfusion techniques.