体外循环后的心律失常与镁剂治疗

应用原子吸收分光光度计，连续测定２８例先天性心脏病患儿血清、红细胞镁的含量和２０例四联症心肌内镁的含量，心肌取自四联症右心室肥厚异常心肌观察体外循环前、后镁的变化及其与心律失常的关系．结果为血清镁显著升高（Ｐ＜０．０１），红细胞镁无显著变化（Ｐ＞０．０５），心肌镁显著下降（Ｐ＜０．０５）。术前预防补镁组镁含量高于非补镁组（Ｐ＜０．０５），补镁组术后心律失常显著降低（Ｐ＜０．０５）。依此缺血再灌注后心肌细胞在高钙同时存在低镁，心肌镁含量明显降低可能是术后发生心律失常的重要原因之一，预防性补镁治疗有显著抗心律失常疗效。

ARRHYTHMIAS AFTER CARDIOPULMONARY BYPASS AND TREATMENT WITH MAGNESIUM

In order to study the change of magnesium level before and after cardiopulmonary bypass(CPB), and relationship between the magnesium level and arrhythmias, we assayed the magnesium in serium, erythrocyte in 28 cases and in myocardium gained from hypertrophic muscle band of right ventricle in 20 cases of tetralogy of follot using atomic absorption stetrophotometry. The results revealled the level of manesium in serium was higher in CPB than that in pre-CPB(P<0 . 01) ,and the level of magnesium in myocardium after holding-up aortae was lower than that before clamping aortae (P<0.05), but there was not change in erythrocyte peri-CPB. The level of magnesium in myocardium was higher and the incidence of arrhythmias was lower (P<0. 05) in 10 patients were given potassium magnesium aspartate than that in control group. It could be sure that the cardiac muscle cell exists both calcium overload and low manesium after reperfusion. The decreased magnesium in myocardium is probably a main cause of postoperative arrhythmias. The preventive supplement magnesium can reduce the incidence of arrhythmias.