犬希氏束起搏的心脏电生理和血液动力学效应研究

目的:探讨希氏束起搏电极定位技术及心脏电生理和血液动力学变化特点。方法:健康犬在全麻呼吸机通气下,开胸,将特制希氏束(HisB)标测/起搏电极进行HisB电位标测,确定HisB起搏位点;并将心室起搏电极固定于右室尖部分别构成HisB-_VVI、RVA-_VVI单腔心脏起搏,对比分析其心脏电生理和血液动力学参数变化。结果:HisB起搏阈值参数符合心室起搏要求;HisB-_VVI起搏QRS波较RVA-_VVI起搏变窄;心输出量(CO)较自身增加18.81%,RVA-_VVI起搏反而降低约5.41%;每搏量(SV)接近于自身窦性心律,但明显高于RVA-_VVI起搏约25.59%;左室每搏功(LVSW)和右室每搏功(RVSW)等参数亦明显优于RVA-_VVI心脏起搏。结论:HisB起搏由于将心室起搏位点从传统的右室尖改为His束,从而保持了近于正常生理性心室激动顺序和心室收缩同步性,故可维持整个心脏协调有序的收缩和舒张,产生优于RVA-_VVI起搏的血液动力学效果。

Effect of cardiac pacing with a His bundle lead on cardiac electrophysiol ogical and haemodynamical action in dogs

AIM: To evaluate the effect of cardiac pacing with a His bundle lead on cardiac electrophysiological and haemodynamical action in dogs and the experience of location technique with His bundle pacing lead. METHODS: With opening chest operation in general-anesthetized dogs, a special lead was located at His bundle based on a typical "H" wave and narrow duration of the QRS wave recorded in ECG; Platinum leads were fixed at the epicardium of the right ventricular apex (RVA) respectively, forming HisB- VVI pacing,RVA- VVI pacing. Cardiac electrophysiological and haemodynamical parameters were compared in sinus rhythm and the different pacing models. RESULTS: The threshold of HisB pacing is similar to that of RVA pacing. Cardiac output(CO)is increased about 18.81% in HisB- VVI pacing than self. It is decreased about 5.41% in RVA- VVI pacing. SV is similar to self,but it is 25.59% higher in HisB- VVI than RVA- VVI . LVSW and RVSW in His B- VVI pacing is superior to that in RVA- VVI . CONCLUSION: His bundle pacing significantly improves cardiac function compared with the RVA- VVI pacing because it can maintain normal physiological electronic activation sequence and systolic synchrony and have a better haemodynamics effect.neral-anesthetizeddogs,as