【摘要】 目的　应用心外膜标测技术观察 类新药 Ambasilide对迷走性持续心房颤动 (房颤 )的影响 ,并与普罗帕酮比较 ,研究其电生理作用机制。方法　建立迷走神经性持续房颤模型 ,13只犬给予普罗帕酮 (2 m g/ kg) ,另 13只犬给予 Ambasilide(2 mg/ kg) ,观察两药对房颤的终止情况 ,同时在用药前后进行心房电活动实时心外膜标测及心房有效不应期的测量。结果　普罗帕酮 2 mg/ kg负荷量可转复房颤 11/ 13(84.6 % ) ,Ambasilide 2 m g/ kg负荷量可转复 13/ 13(10 0 % )。当 S1 S1 为 40 0 m s时普罗帕酮可使心房有效不应期从 (149± 6 ) ms增至 (181± 5 ) m s,增加率为 2 3%± 4% ,而 S1 S1 为 2 0 0 m s时 ,心房有效不应期从 (12 0± 6 ) ms增至 (192± 4) ms,增加率达 6 6 %± 8% ,心房有效不应期增加为正向频率依赖性 (P<0 .0 1)。当 S1 S1 为 40 0 m s时 Ambasilide可使心房有效不应期从 (16 4± 3) ms增至 (2 14± 7) ms,增加率为 31%± 4% ,而 S1 S1 为 2 0 0 ms时 ,心房有效不应期从 (12 6± 5 ) ms增至 (15 6± 5 ) ms,增加率2 5 %± 6 % ,心房有效不应期增加为非频率依赖性 (P>0 .0 5 )。普罗帕酮在 S1 S1 为 2 0 0 m s时可减慢心房传导速度达 34%± 4% ,而 Ambasilide对心房传导速度无影响。两药均可延?更多还原

【Abstract】 Objective To evaluate the effects of propafenone and ambasilide on sustained experimental atrial fibrillation (AF) and to study its electrophysiologic mechanisms by using computer based 112 electrode epicardial mapping system.Methods Using sustained cholinergic AF model,propafenone and ambasilide (2 mg/kg)were given to 26 dogs to assess the ability to terminate AF.Atrial epicardial electrophysiologic activities were mapped and atrial effective refractory period(AERP) were measured at four different basic cycle lengths(BCL) at baseline and after drug administration.Results Propafenone of 2 mg/kg terminated AF by 84.6% and ambasilide terminated AF by 100%.Propafenone increased AERP by 23%±4% [from(149±6) ms to (181±5) ms]at BCL 400 ms.And propafenone increased AERP by 66%±8% [from (120±6) ms to (192±4) ms]at BCL 200 ms;Effects of propafenone on AERP showed strong rate dependent fashion.Ambasilide increased AERP by 31%±4% [from (164±3) ms to (214±7) ms]at BCL 400 ms.It increased AERP by 25%±6% [from(126±5) ms to (156±5) ms]at BCL 200 ms.It had rate independent effects on AERP.Propafenone slowed atrial conduction velocity to 34%±4% but ambasilide did not change it.Both drugs could increase atrial wavelength.Conclusions (1)Both propafenone and ambasilide could terminate vagotonic AF by increasing AERP and wavelength;(2)Propafenone increased AERP with rate dependent fasion but ambasilide with rate independent one;(3)Propafenone slowed atrial conduction velocity but ambasilide had no effects on it.更多还原