Antiarrhythmic effect of magnesium sulfate after open heart surgery: effect of blood levels.
BACKGROUND
Arrhythmias following cardiac surgery is still a difficult complication to treat. Magnesium sulfate is an effective antiarrhythmic agent with negligible side effects. In this study, effects of magnesium sulfate as a first line antiarrhythmic agent was compared with results of two different well-accepted antiarrhythmic agents.


METHODS
One hundred patients with arrhythmia were prospectively randomized to a study and a control group. Lidocaine and amiodarone were accepted as standard antiarrhythmic agents. Patients in study group were received magnesium sulfate routinely as a first line antiarrhythmic agent. Unresponsive arrhythmias were treated with standard antiarrhythmic agents. Control group patients received only standard antiarrhythmics.


RESULTS
Magnesium sulfate alone was effective in 56% of the study group whereas 74% of the control group were responsive to standard antiarrhythmics (P=n.s.). In study group, a subgroup analysis according to blood levels of Mg2+ revealed that magnesium sulfate was more effective in patients with low Mg2+ levels (63% for low Mg2+ levels, 55% for normal Mg2+ levels, 36% for high Mg2+ levels) and ventricular arrhythmias (60% for ventricular and 40% for supraventricular arrhythmias), without statistical significance.


CONCLUSIONS
Magnesium sulfate is an effective and safe antiarrhythmic agent for arrhythmias developed after open-heart surgery. Its antiarrhythmic effect may relate to its pharmacological properties and unrelated to normalization of the circulating magnesium concentrations. We recommend its use as a first line antiarrhythmic agent without routine measurement of blood levels.
Kiziltepe
Ugursay
U
Department of Cardiovascular Surgery, Ankara University School of Medicine, Ankara, Turkey. uk9316@hotmail.com <uk9316@hotmail.com>
Eyileten
Zeynep Bastuzel
ZB
Sirlak
Mustafa
M
Tasoz
Refik
R
Aral
Atilla
A
Eren
Neyyir Tuncay
NT
Uysalel
Adnan
A
Akalin
Hakki
H
D000368:Aged; D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001145:Arrhythmias, Cardiac / Q000188:drug therapy* / Q000209:etiology*; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000627:therapeutic use; D008274:Magnesium / Q000097:blood*; D008278:Magnesium Sulfate / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
D000889:Anti-Arrhythmia Agents; D008278:Magnesium Sulfate; D008012:Lidocaine; D008274:Magnesium; D000638:Amiodarone