步长稳心颗粒对心力衰竭兔心室肌电生理特性的影响

Influence of Wenxin Keli on ventricular electrophysiology in rabbits with congestive heart failure

目的研究步长稳心颗粒对心力衰竭(简称心衰)兔心室肌在体电生理特性的影响。方法将32只日本大耳兔分为四组:假手术组、假手术稳心颗粒组、心衰组、心衰稳心颗粒组。采用主动脉瓣返流联合腹主动脉缩窄的方法制作心衰模型,假手术稳心颗粒组和心衰稳心颗粒组用稳心颗粒干预,8周后开胸记录心室肌单向动作电位(MAP)及有效不应期(ERP),左室心尖三层心肌的动作电位复极90%时程(MAPD90)并计算跨室壁复极离散度(TDR),测量心室颤动阈值(VFT)。结果与心衰组比较,心衰稳心颗粒组左室射血分数和左室短轴缩短率显著增高(P均<0.05),而左室收缩末及舒张末内径、容积均缩小(P<0.05)。与假手术组比较,假手术稳心颗粒组和心衰组的心室肌MAPD50、MAPD90、ERP延长(P均<0.05),但心衰组和心衰稳心颗粒组间并无统计学差异(P>0.05)。与假手术组、心衰稳心颗粒组比较,心衰组左室中层心肌细胞MAPD90明显延长(P<0.05),TDR明显增加(P<0.05);与心衰组比较,心衰稳心颗粒组的VFT明显升高(P<0.05)。结论稳心颗粒可能通过缩短TDR和提高VFT起到抗心衰时室性心律失常作用;并不能使心衰时已延长的MAPD和ERP发生改变。

Objective To investigate the influence of Wenxin Keli on ventricular electrophysiology in rabbits with con- gestive heart failure （HF）. Methods Total 32 rabbits were randomly divided into four groups： sham group, the sham-op- erated Wenxin Keli group, HF group and HF Wenxin Keli group. HF model was successfully produced by combined aortic insufficiency and abdominal aortic constriction. These rabbits in Wenxin Keli group were feed by Wenxin Keli. Eight weeks later, ventrieular myoeardium monophasic action potential duration（ MAPD）, effective refractory period （ERP）, transmu- ral dispersion of repolarization （TDR） and ventricular fibrillation threshold （vFr） were measured. The electrophysiologic parameters were evaluated by the technique of standard electric stimulation and MAP recording. Results Compared with HF group , the rabbits in the HF Wenxin Keli exhibited significantly larger left ventricular ejection fraction and left ventricu- lar shorting fraction, smaller left ventricular end-diastole dimension, left ventricular end-systole dimension, left ventrieular end-diastole volume and left ventrieular end-systole volume（ all the P 〈 0.05）. Compared with sham group,the ventricular duration of MAP at 50% （ MAPDs0 ） and 90% repolarization（ MAPDgo ） ,ERP were prolonged in sham-operated Wenxin Ke- li group and HF Wenxin Keli group（P 〈 0.05）, But difference between HF group and HF Wenxin Keli group were no sig- nificant （P 〉 0. 05 ）. Compared with sham group and HF Wenxin Keli group, the MAPD90 of the middle layer myocardium of left ventricular was prolonged in HF group （ P 〈 0.05 ）, TDR was larger in HF group （ P 〈 0. 05 ）. Compared with HF group, VFT were remarkably inereased in HF Wenxin Keli group （ P 〈 0. 05 ）. Compared with sham group, VFT were in- creased in sham-operated Wenxin Keli group （ P 〈 0. 05 ）. Coelusions Wenxin Keli could shorten TDR and elevated VFF which were protective function in heart failure aecompaning with arrhythmia, and couldn＇t change the prolonged MAPD and VER in rabbits with HF.