左心室内膜起搏对犬失同步化缺血性心力衰竭心电生理的影响

Impact of left ventricular endocardial pacing on cardiac electrophysiology of canine asynchrony ischemic heart failure

目的研究失同步化缺血性心力衰竭在左心室内膜起搏下心电生理的变化。方法应用左束支射频消融术和冠状动脉前降支结扎术建立18只健康犬缺血性心力衰竭模型。使用随机数字表法对18只健康犬进行分组,每组各9只。实验组行左心室内膜心脏再同步化治疗(CRT),对照组行假手术,术后6周检查心电图、超声心动图。结果实验组左室射血分数明显高于对照组(38.32±6.08 vs.30.62±8.96),失同步化指数显著低于对照组(35.99±5.25 vs.78.21±7.02),差异均有统计学意义(均P<0.05)。实验组QRS(60.58±7.43 vs.68.33±8.01)、QTc(347.09±17.33 vs.367.81±22.02)均显著短于对照组(均P<0.05);且Tp-e(37.03±9.07 vs.45.76±7.11)、ARI(162.33±22.06 vs.187.21±23.87)均明显少于对照组(均P<0.05)。结论左心室内膜起搏可以产生较好的电生理效应,达到有效的心脏再同步治疗目的。

Objective To study the cardiac electrophysiology changes of canine asynchrony ischemic heart failure under left ventricular endocardial pacing. Methods Left bundle branch radiofrequency catheter ablation and left anterior descending coronary artery ligation were used to establish the model of ischemic heart failure in 18 healthy dogs. Eighteen healthy dogs were randomly divided into two groups, 9 cases in each group. The experimental group was treated with cardiac resynchronization therapy（CRT） in left ventricular endocardium,and the control group underwent the sham operation. ECG and echocardiography were done at 6 weeks after operation. Results The left ventricular ejection fraction in the experimental group was significantly higher than that in the control group（38.32 ± 6.08 vs. 30.62 ± 8.96）. The asynchronization index in the experimental group was significantly lower than that in the control group（35.99±5.25 vs. 78.21± 7.02） ,and the difference was statistically significant（P〈0.05）. QRS（60. 58± 7.43 vs. 68.33 ± 8.01） and QTc（347.09 ± 17.33 vs. 367.81 ± 22.02）in the experimental group were significantly shorter than those in the control group（P〈0.05） ;moreover Tp-e（37.03±9.07 vs. 45.76±7.11） and AR1（162.33±22.06 vs. 187.21±23.87） in the experimental group were significantly lower than those in the control group（P〈0.05）. Conclusion Left ventricular endocar dial pacing can produce preferably electrophysiological effects and achieve the goal of effective cardiac resynchronization therapy.