Relation of cardiovascular disease to potassium and magnesium deficiencies.

Potassium and magnesium deficiencies, particularly those induced by conventional loop and thiazide diuretic therapy, have been linked in clinical studies to an increased frequency in serious arrhythmias and mortality in acute myocardial infarction. Magnesium repletion has been shown not only to increase magnesium levels, but also to increase muscle potassium and to decrease the frequency of ventricular ectopic beats. Potassium replenishment alone may have a detrimental effect in magnesium-depleted patients. The potassium-sparing diuretic spironolactone (Aldactone) has been shown to spare both potassium and magnesium, and may therefore be a more appropriate diuretic therapy in patients at cardiovascular risk.