伊布利特对心力衰竭犬不应期恢复性和除颤阈值的影响  

Effect of ibutilide on ventricular refractory period restitution and defibrillation threshold in canine heart failure model

作　　者：罗庆志[1] 张凝[1] 金奇[1] 吴琼[1] 柳韶华[1] 韩岩新 林长坚[1] 凌天佑[1] 潘文麒[1] 吴立群[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院心脏科,上海200025

出　　处：《中国心脏起搏与心电生理杂志》2015年第1期50-53,共4页Chinese Journal of Cardiac Pacing and Electrophysiology

基　　金：国家自然科学基金(81270260);上海市科委(13140903702)

摘　　要：目的通过快速心室起搏建立犬心力衰竭(HF)模型,观察伊布利特对HF犬的心室不应期及不应期恢复性的影响,探讨其抗心室颤动(VF)的潜在电生理机制。方法选取6只健康成年比格犬,通过右室心尖部快速起搏4周制作犬慢性HF模型,开胸后应用心外膜电极片(共12×12个单极电极,每个电极间的距离为2 mm)标测左室心外膜心肌电激动。应用伊布利特前后[负荷剂量:以10μg/kg静脉推注,并以0.1 mg/(kg·h-1)的速度静脉维持],通过S1S2刺激测定心室有效不应期(VERP),采用连续刺激法诱发VF并同时测定激动恢复间期(ARI),进而通过ARI来评估不应期恢复曲线的最大斜率,并测定除颤阈值(DFT)。结果与基础状态相比,伊布利特可明显延长HF犬的VERP[(208.0±18.9)ms vs(178.0±9.6)ms,P<0.05]和ARI[(171±11)ms vs(165±14)ms,P<0.01]。同时,伊布利特显著降低不应期恢复性曲线的最大斜率达41%(0.83±0.07 vs 1.40±0.09,P<0.01)。伊布利特可显著降低DFT[(13.0±2.7)J vs(18.0±2.0)J,P<0.01]。结论伊布利特可显著降低HF犬的除颤阈值,其潜在机制可能为延长心室不应期和降低不应期恢复性曲线的最大斜率。Objective To explore the possible electrophysiological mechanism of ibutilide by observing its effect on ventricular refractory period restitution and defibrillation threshold （DFT） in canine heart failure model. Methods Six healthy adult beagle dogs were used to establish chronic heart failure model by rapid right ventricular pacing for 4 consecutive weeks. An epicardial mapping plaque of 144 electrodes （12× 12, electrodes spacing 2 mm） was sutured on the anterior epicardium of left ventricule. Before and after the administration of ibutilide [ 10 μg/kg intravenously as loading dose and 0.1 mg/（ kg · h^-1） intravenously as maintenance dose], ventricular effective period （VERP） were measured by S1 S2 pacing protocol. Venricular fibrillation （VF） was induced by a programmed pacing protocol, and activation recovery interval （ARI） were measured. The maximal slope of refractory period restitution was estimated from ARI. DFT was then determined. Results Compared with to baseline, ibulitide significantly prolonged VERP[ （208 ± 18.9 ） ms vs （ 178 ± 9.6） ms, P〈0.05 ] and ARI [ （171 ±11 ） ms vs （165 ±14） ms, P〈0. 01 ]. Additionally, the drug significantly reduced the maximum slope of ARI restitution curve by 41% （0.83 ±0.07 vs 1.40 ±0.09, P〈0. 01 ）, DFT was significantly decreased by ibutilide [ （13.0 ±2.7） J vs （18.0±2.0） J, P〈0. 01 ） ]. Conclusion Ibutilide significantly decreases DFT in canine heart failure model ,the anti-fibrillation effect may relate to prolongation of VERP and flattening of ventricular restitutioncurve.

关 键 词：心血管病学 伊布利特 心室颤动 心力衰竭 恢复性 除颤阈值 

分 类 号：R541.7[医药卫生—心血管疾病] R972.2[医药卫生—内科学]