MAGNESIUM-SULFATE IN THE TREATMENT OF VENTRICULAR ARRHYTHMIAS DUE TO DIGOXIN TOXICITY

Although digoxin antibodies are the definitive treatment of cardiac ar rhythmias due to digoxin toxicity, magnesium can also be effective esp ecially with low serum magnesium levels. The care report describes a p atient with digoxin toxicity, ventricular tachycardia and a slightly e levated serum magnesium. Two 10 mmol doses of intravenous magnesium su lfate were associated with a more stable junctional rhythm with bigemi ny. Magnesium is known to suppress early after depolarizations, and in supraphysiological doses, may act as an indirect antagonist of digoxi n at the sarcolemma Na+-K+-ATPase pump. Intravenous magnesium may be u sed to treat cardiac arrhythmias due to digoxin poisoning where there is likely to be a delay in the availability of digoxin antibodies, eve n in the presence of elevated serum magnesium.