Magnesium content of the human heart

Although changes in the body's magnesium status have been linked to ischemic heart disease, sudden death and arrhythmia, there is as yet no recommended, established procedure for evaluation of magnesium homeostasis. We therefore explored the relationship between the magnesium content of the heart and that of serum, lymphocytes and skeletal muscle in 50 men undergoing cardiac surgery, using biopsies from the right auricula, right atrium and skeletal muscle and simultaneously drawn venous blood for measurement of lymphocyte and serum electrolyte concentration. Median magnesium values (mumol/g wet weight) were 7.42 (3.98-8.89) in skeletal muscle, 5.49 (3.44-7.66) in right auricula and 5.80 (2.60-7.53) in right atrium. The magnesium concentration in skeletal muscle was found to correlate with that in right auricula (r = 0.46, p less than 0.01) and right atrium (r = 0.43, p less than 0.01), whereas values in serum and lymphocytes showed no correlation with the heart's magnesium content. When myocardial biopsy is not available, skeletal muscle magnesium concentration seems to be the best predictor of the human myocardium's magnesium status.