Abstract: AIM:To evaluate the efficacy of magnesium sulfate combined with amiodarone in the treatment of refractory ventricular tachycardia. METHODS: One hundred and thirty-six ICU patients with ventricular tachycardia were retrospectively analyzed. Patients were divided into two groups: magnesium sulfate group with treatment of magnesium sulfate combined with amiodarone (n=72) and amiodarone group (n=64) with treatment of amiodarone only. The cardioversion efficacy of magnesium sulfate was evaluated. RESULTS: There was no difference in aspects such as electric power, load dose of amiodarone and 28-day mortality rate between groups. The times of electric cardioversion ［(1.4±0.9) times vs.(3.0±2.2) times, P<0.01］ and the maintenance dose of amiodarone ［(0.9±0.6) g vs.(2.3±1.2) g, P<0.01］ in the magnesium sulfate group were significantly lower than those in the amiodarone group. The success rate of cardioversion in 30 min (33% vs. 9%, P<0.01) and 24 h (97% vs. 78%, P<0.01) and the rate of maintaining success for 72 h (97% vs. 84%, P<0.01) in the magnesium sulfate group were significantly higher than those in the amiodarone group. The success rate of cardioversion in 2 h in the magnesium sulfate group was higher than in the amiodarone group (81% vs. 62%, P<0.01). The period of ICU stay in the magnesium sulfate group was shorter than in the amiodarone group ［(7.4±3.9) days vs.(9.1±5.2) days, P<0.05］. CONCLUSION: Magnesium sulfate combined with amiodarone has good efficacy for cardioversion and a high rate of maintaining success in patients with refractory ventricular tachycardia.