The value of serum magnesium estimations in the diagnosis of acute perioperative myocardial infarction after coronary artery surgery.

Serum magnesium levels fall significantly after acute myocardial infarction. Even greater decreases have been found in all patients undergoing aorto-coronary bypass surgery. This is probably related to the use of cardiopulmonary bypass. No significant difference in serum magnesium levels was found between those patients who had a well documented peri-operative infarct and those who had an uncomplicated course. Thus determination of serum magnesium levels if of no use in the diagnosis of peri-operative myocardial infarction.