Efficacy and Mechanism of Intravenous Sotalol for Termination of Paroxysmal Supraventricular Tachycardia

Objectives To study the efficacy and mechanism of intravenous sotalol(Sol) for termination of paroxysmal supra ventricular tachycardia (SVT). Methods Sol or normal saline (NS) were administrated intravenously in patients with SVT induced by trans esophagus left atrial stimulation. Results Conversion to sinus rhythm occurred in 65.2%(15/23) patients who received Sol (Sol group) at total dose of 1.5 mg/kg, the average conversion time being (10.7±11 6) min after the start of sotalol infusion. Conversion to sinus rhythm appeared in 4.8%(1/21) patients who were treated with NS(NS group). The efficacy between two groups was significantly different (P<0 01). The site of termination of tachycardia was predominantly at the antegrade atrioventricular node (AVN) in atrioventricular reentrant tachycardia (AVRT) (3/4) and at the retrograde fast pathway of AVN in atrioventricular nodal reentrant tachycardia (AVNRT)(4/6). During the course of Sol infusion, both ventricular rate of SVT and systolic blood pressure (SBP) decreased. HR decreased from (173.3±28.4) min -1 (before Sol administration) to (159.6±23.8) and (152.0±22.2) min -1 (3,5 minutes after the start of Sol infusion respectively, P<0.01) and SBP from (16.31±2.27) kPa to (14.82±2.61) and (14.61±2.60) kPa(P<0.01). Transient hypotension (SBP <10.7 kPa) occurred in 2 patients during the course of Sol administration. There were no significant changes of HR and blood pressure in the NS group. Conclusion It was safe and effective for sotalol administration on SVT.