ENALAPRIL PRESERVES SINUS NODE FUNCTION IN A CANINE BRADYCARDIA-TACHYCARDIA SYNDROME MODEL

摘要

The aim of this study was to investigate effects of enalapril on sinus node dysfunction associated with atrial fibrillation. Eighteen beagles were pretreated with placebo (Group-I, n=10) or enalapril lmg/kg/day (Group-II, n=8). In group-I, 4 weeks of rapid atrial pacing prolonged corrected sinus node recovery time (CSNRT) in dogs without AV ablation (from 281.3 + 27.8 to 811.3 + 52.4 ms, p<0.05). Enalapril significantly shortened CSNRT (409.8 +- 37.2 ms, p<0.005) compared with Group-II by suppressing fibrosis around the sinus node (9.2+ 9.1% v.s2.2+-2.3 %, p<0.05). These findings suggest the suppression of fibrosis around SN by enalapril may play an important role to preserve sinus node function in bradycardia-tachycardia syndrome.