[Effect of magnesium containing cardioplegic solution on the cases of extended aortic cross clamping].

We have investigated about the preservation of myocardium using magnesium containing cardioplegic solution. In this study we have concluded that magnesium containing cardioplegic solution is effective especially in the cases of extended Aortic cross clamping. 91 cases were availed for studying the post-operative cardiac function, and 32 cases of which were availed for seeking the content of calcium and magnesium of the myocardium. GK-Mg solution was superior in the post-operative cardiac function, and in the total CPK-MB. The retention of calcium in the myocardium after Ao declamping was higher in the cases of using GK solution. And Ca.Mg ratio was also higher in GK solution. Especially in the cases of extended Ao cross clamping, increase of calcium in the myocardium and Ca.Mg ratio was suppressed by using the GK.Mg solution. Although magnesium have several effects on the myocardium, but we think that suppressing the influx of calcium into the myocardium is one of the most important factor of the magnesium for the preservation of myocardium.