Safety and Therapeutic Efficacy Evaluation of Intravenous Metoprolol for Control of Ventricular Rate in Patients with Rapid Atrial Fibrillation

To observe the safety and efficacy of intravenous metoprolol for control of ventricular rate in patients with rapid atrial fibrillation.Metoprolol 5 mg was injected iv. consecutively for 3 times within 10 min with an interval of 2 min in 98 eligible patients with rapid atrial fibrillation [ventricular rate100 beats/min(bpm)] , then followed by 50 mg po. q6h. The effective rate (decline of ventricular rate ≥20%) and changes of symptom and physical sign were followed up.The effective rate of 15 mg intravenous metoprolol in 10min after injection was 83.7%, the ventricular rate decreased from (133.7±18.3) bpm to (91.4±12.6) bpm ; while that of metoprolol po. 24 h after administration was 93.9%, and the ventricular rate decreased further to (79.5±8.9) bpm. Tolerable hypotensive state (85～90/55～60 mmHg) appeared in patients, but serious bradycardia (HR 50bpm), atrioventricular block grade Ⅱ/Ⅲ, worsening cardiac function and death were not observed.[Conclusion]Intravenous metoprolol is safe and efficacious to treat the patients with rapid atrial fibrillation.