IN 1935,
Zwillinger reported that administration of magnesium, Mg 2+, restored sinus
rhythm in patients with digitalis-induced tachyarrhythmias. Since that time, Mg2+
has been used for prophylaxis or therapy in a variety of cardiovascular disorders.Administration of MgSO4 during electrophysiologic
evaluation of patients has demonstrated two effects of Mg 2+ relevant to the
treatment of supraventricular tachyarrhythmias:
- prolongation of atrioventricular nodal conduction
time (anterograde and retrograde) and refractory period and
- suppression of conduction in accessory pathways with
and without atrioventricular node-like properties
Other antiarrhythmic effects of Mg2+ have been
reported, although the underlying mechanisms have not been defined:
- restoration of sinus rhythm in critically ill medical
and surgical patients with supraventricular tachycardias
- suppression of intractable ventricular
tachyarrhythmias
- control of ventricular rate in new-onset atrial
fibrillation (AF) prophylaxis of AF after coronary artery bypass grafting
- slowing of digoxin-facilitated ventricular rate
during AF in Wolff-Parkinson-White syndrome
- abolition of preexcitation (Delta wave) in patients
with Wolff-Parkinson-White syndrome during normal sinus rhythm
- suppression of multifocal atrial tachycardia
- suppression of digoxin-induced ectopic
tachyarrhythmias
- prevention of bupivacaine-induced arrhythmias
- treatment of amitriptyline-induced ventricular
fibrillation.
Mark N. Gomez, MD:Magnesium and Cardiovascular Disease .ANESTHESIOLOGY
1998;89:222-240
