The Effect of Magnesium Depletion on the Electrocardiogram and Plasma Electrolytes in Liver Cirrhosis

Plsama and urinary Mg were measured in relation to EKG change in 24 patients with liver cirrhosis, and summarized as below. 1. Plasma albumin and Ca were below normal, however Na, K, and Mg level were in the lower limit of normal. 2. Abnormal EKG findings were QT prolongation, ST elevation, peaked T, low T, ST depression and U wave in the order of frequency. 3. Coefficient of correlation between plasma Mg and QT prolongation was -0.5 compared with that of Ca-0.28. 4. Mg depletion was moderately correlated with plasma albumin (r=0.59). 5. Marked urinary Mg excretion in the presence of normal plasma Mg suggest that plasma Mg level poorly reflect total Mg depletion.