Prevention of atrial tachyarrhythmias after non-cardiac thoracic surgery by infusion of magnesium sulfate.

The possible role of magnesium sulfate (MgSO4) infusion in the prevention of atrial tachyarrhythmias after non-cardiac thoracic surgery was evaluated through a prospective study of two hundred patients who underwent non-cardiac thoracic surgery. The patients (who fulfilled the following requirements among others: no myocardial infarction in the previous six months, normal renal function, no use of digitalis or antiarrhythmic drugs, not undergone emergency operations or video-assisted thoracic surgery), were randomly assigned to receive MgSO4 infusion in all circumstances (Mg group), or either no treatment or, if aged over 70 or in cases of pneumonectomy or an intrapericardial procedure, application of digoxin starting on the day of operation (control group). 95 patients were enrolled in the Mg group and 105 in the control group. 93 patients in the Mg group and 101 in the control group were evaluated. Post-operative atrial tachyarrhythmias, mainly atrial fibrillation, occurred in 10 patients (10.7%) in the Mg group and in 27 (26.7%) patients in the control group (chi 2 = 7.009, df = 1. p = 0.008). It is concluded that infusion of MgSO4 is an effective means of reducing the incidence of atrial tachyarrhythmias after non-cardiac thoracic surgery.