应用二维斑点追踪技术评价左心室心外膜多点电极同步治疗动物实验研究

Evaluation of left ventricular epicardial multi-point electrode pacemaker implantation in the therapy of cardiac resynchronization with two-dimensional speckle tracking echocardiography

目的应用二维斑点追踪成像技术评价微创外科方法植入左心室心外膜多点电极的心脏再同步化治疗（CRT）的可行性和疗效。方法 11头中华小型猪,雌雄不限,体质量22.0~26.4 kg,平均体质量24.6 kg。以快速心室起搏诱发心力衰竭造动物模型,其中6头（实验组）接受左心室心外膜多点电极起搏器植入;5头为对照组,接受左心室单点冠状静脉窦植入电极。应用二维斑点追踪成像技术对左心室心肌同步性治疗进行影像获取。对术前与术后的左心室短轴径向应变、长轴纵向应变、圆周应变及局部心肌旋转进行分析。结果 CRT后,实验组左心室长轴纵向应变、圆周应变、局部心肌旋转分别为11.76±1.32、12.52±1.31、6.44±1.81,对照组分别为8.97±1.47、10.68±2.64、4.61±1.37;实验组较对照组明显提高,差异有统计学意义（P﹤0.05）。两组间左心室短轴径向应变（17.47±2.94 vs 17.96±3.45）差异无统计学意义。结论左心室心外膜多点电极起搏器植入更能提高左心室的收缩与舒张功能,应用二维斑点追踪成像技术可对左心室同步性进行准确评价。

Objective To evaluate the feasibility and efficacy of minimally invasive surgical method with two-dimensional speckle tracking echocardiography（STE） in animals after cardiac resynchronization therapy（CRT）. Methods Rapid left ventricular pacing was utilized in 11 adult pigs（either male or female, body weight of 22.0 - 26.4 kg with mean of 24.6 kg） to induce heart failure, which were randomly divided into experimental group （n = 6） and control group （n = 5）. The experimental group received CRT using left ventricular epicardial multi-point electrode pacemaker and control group was implanted with left ventricular single coronary sinus electrode. Two- dimensional STE was performed to evaluate left ventricular myocardial synchrony before and after the pacemaker implantation, and the radial strain（RS）, longitudinal strain（LS）, circumferential strain（CS） and regional myocardial rotation（Rot） were analyzed and compared. Results After CRT, L5, CS and Rot of experimental group were 11.76 ± 1.32, 12.52 ± 1.31 and 6.44 ± 1.81, respectively, which were significantly higher than those of control group（8.97 ±1.47, 10.68 ± 2.64 and 4.61 ±1.37, respectively）（P 〈 0.05）. No significant difference in RS between 2 groups（17.47 ± 2.94 vs 17.96 ± 3.45） was observed. Conclusion It is demonstrated that the left ventrieular epieardial multi-point electrode pacemaker implantation could improve the systolic and diastolic function of left ventricule, and the two-dimensional STE could provide precise data about left ventricular myocardial synchrony.