Value of serum magnesium estimation in diagnosing myocardial infarction and predicting dysrhythmias after coronary artery bypass grafting.

Serial serum magnesium estimations, beginning before operation, were performed on 200 patients who underwent coronary artery bypass grafting. The results indicate that serum magnesium concentration is of no value in the diagnosis of myocardial infarction in the postoperative patient or in predicting which patients are susceptible to postoperative dysrhythmias. There was no statistically significant difference in serum magnesium values between those patients who had an uncomplicated course and patients who had sustained either myocardial infarction or postoperative dysrhythmia or both.