Lfm. Barros et al., MAGNESIUM TREATMENT OF ACUTE MYOCARDIAL-INFARCTION - EFFECTS ON NECROSIS IN AN OCCLUSION-REPERFUSION DOG-MODEL, International journal of cardiology, 48(1), 1995, pp. 3-9
The effects of plasma magnesium elevation on myocardial necrosis were
tested in anesthetized dogs submitted to left anterior descending coro
nary artery occlusion and reperfusion. Eighteen dogs were treated with
magnesium sulfate soon after the coronary occlusion in order to trebl
e the plasma concentration, while 18 others remained as controls. The
treatment determined only slight reductions in the heart rate and in t
he arterial blood pressure, from the beginning to the end of the exper
iment. The percent necrosis of the ischemic myocardium was determined
by staining and weighing the normal, the preserved and the necrotic ar
eas. Necrosis was noticed in 63.7 +/- 16.8% and 44.2 +/- 20.8% of the
risk area in the control and treated groups, respectively (P = 0.004).
It is concluded that the treatment has protected the ischemic/reperfu
sed myocardium reducing the final necrosis of the risk area by about 3
0%. This effect may be ascribed to the hemodynamic changes determined
by magnesium sulfate infusion as well as to metabolic actions during i
schemia and reperfusion.