Multifocal atrial tachycardia responsive to parenteral magnesium

Abstract

Two groups of patients with multifocal atrial tachycardia (MAT) were treated with the intramuscular and continuous intravenous magnesium sulphate regimens used in pre-eclampsia. Both routes of administration were successful in causing reversion to sinus rhythm but the intramuscular regimen, by attaining a higher and more sustained serum magnesium concentration, converted the arrhythmia to normal sinus rhythm in a shorter period of time (1-2 hours) than the intravenous regimen (4-8 hours). Magnesium-sparing diuretics should be used in the treatment of patients with chronic obstructive pulmonary disease and congestive heart failure, which are both conditions associated with magnesium deficiency and MAT.