Abstract: Objective To investigate effect and implication of cardiac performance and electrophysiological induced by structural remodeling with chronic heart failure( CHF) in ventricular of rabbits. Method Thirty two male New Zealand rabbits were randomly divided into 2 groups: the control group ( n = 15) and the CHF group ( n = 17) . The CHF group was used to prepare CHF model by injecting isoprenaline ( ISO) into rabbit ear vein, and finally 15 rabbits were successfully made. The control group was given the same volume of 0. 9% saline, and finally 12 rats entered the experiment. Echocardiography was used to monitor the M-type cardiac function of the 2 groups of rabbits, and lead Ⅱ ECG was recorded. LVEF, Avmax, LVEDd, LVESD, shortening rate of left ventricular short axis were recorded ( LVFS ) , interventricular septal thickness ( IVST ) , left ventricular end diastolic volume ( LVEDV) and left ventricular end systolic volume (LVESV), as well as heart rate, PR interval, QT interval and ST segment, were used to evaluate the changes of ECG physiological function. Programmed stimulation was used to observe the effective refractory period and dispersion of each effective refractory period when the stimulation perimeter (BCL) was 150 ms and 200 ms. To evaluate the BCL and the rate of ventricular arrhythmia (VA) induced by burst packing. Result Compared with the control group, LVEF, LVFS and Avmax of the CHF group were significantly lower, LVEDd and LVESD were significantly longer. IVST was thinner than that of the control group. LVEDV and LVESV were significantly higher than that of the control group ( P < 0. 01) . HR of CHF group was significantly slower than that of the control group ( P < 0. 01) . PR and QT intervals were significantly longer than that of the control group( P < 0. 01 ) . ST segment was significantly lower than that of the control group ( P < 0. 01 ) . The difference was statistically significant. In the CHF group, ERP150 and ERP200 were significantly longer than those in the control group, and both of dERP 150 and dERP200 were significantly larger than those in the control group ( P<0. 01) . The BCL inducing VA was significantly longer than that in the control group, and the VA inducing rate was significantly higher than that in the control group, the difference was statistically significant ( P < 0. 01 ) . Conclusion The ventricular structure and electrophysiological changes of chronic heart failure rabbits were significantly reconstructed, and the interaction between them increased the rate of reentrant VA induction.

Key words: chronic heart failure, structural remodeling, electrophysiological function, arrhythmia

摘要： 目的 探讨慢性心力衰竭( CHF) 兔心室结构重构对心电生理功能的影响及意义。 方法 雄性新西兰兔 32只,随机分为对照组( n = 15)和 CHF 组( n = 17) ,CHF 组采用经兔耳静脉注射异丙肾上腺素( ISO) 制备 CHF 模型,最终造模成功 15 只。 对照组给予相同体积的 0. 9% 生理盐水,最终 12 只进入实验。 采用超声心动图监测两组兔M 型心功能并记录Ⅱ 导联体表心电图,分别记录左心室射血分数( LVEF) 、主动脉最大流速( Avmax) 、左心室舒张末期内径( LVEDd) 、左心室收缩末期内径( LVESD) 、左室短轴缩短率 ( LVFS) 、室间隔厚度( IVST) 、左心室舒张末期容积( LVEDV) 、左心室收缩末期容积( LVESV) 、心率、PR 间期、QT 间期和 ST 段,评价心电生理功能变化。 程控刺激法观察刺激周长( BCL)为 150 ms 和 200 ms 时,心室有效不应期( ERP150 和 ERP200 ) 以及各自有效不应期离散度( dERP150 和 dERP200 ) 。 评价短阵快速刺激法诱发室性心律失常( VA) 的 BCL 及诱发率。 结果 与对照组相比, CHF 组兔的 LVEF、LVFS 及 Avmax 显著下降,LVEDd 和 LVESD 明显延长, IVST 较对照组变薄,LVEDV 和 LVESV 明显增大,差异极显著( P< 0. 01) ;HR 明显减慢,PR 及 QT 间期显著延长,ST 段明显下移,差异极显著( P < 0. 01) ; ERP 150 和 ERP200 明显延长,且 dERP150 和 dERP200 显著增大,诱发 VA 的 BCL 明显延长,VA 诱发率明显高于对照组,差异极显著( P<0. 01) 。 结论 CHF 兔心室结构发生显著的重构,心室电生理异常改变,二者相互作用,使折返性 VA 诱发率增加。

关键词: 慢性心力衰竭, 结构重构, 心电生理功能, 心律失常