超声物理因素对心室肌消融效果的影响  

An experimental study of the influence Of various factors of ultrasound on the myocardial lesions in an in vitro thermodynamic model

作　　者：董军[1] 罗开良 黄晶 邓建川 李伦旭[2] 殷跃辉 

机构地区：[1]重庆医科大学第二临床学院心血管内科,400010 [2]重庆医科大学临床学院麻醉科,400016

出　　处：《重庆医科大学学报》2000年第3期249-252,共4页Journal of Chongqing Medical University

摘　　要：目的 探讨超声物理因素对其损伤灶的影响。方法 使用自行研制的超声导管消融系统，在犬离体右室或左室游离壁热动力学模型上进行超声心室肌消融，并与射频消融比较。结果 电功率与超声损伤灶深度线性相关，损伤面积与辐照时间有正相关关系。电功率是超声消融损伤深度较理想的预测因素，能量是描述损伤面积较好的物理量。换能器／组织接触压与损伤灶大小无明显关系。超声损伤灶的深度远大于射频损伤灶的深度。结论 与射频消融相比，超声消融可造成更深的心肌损伤灶，提示超声消融有可能消除位于较深心肌中的致心律失常病灶，这对于心肌梗塞后室性心动过速的消融有较大的意义。Objective To investigate the influence of various physical factors on the size of the resultant lesion during ultrasound catheter ablation. Methods An ultrasound catheter ablation system was constructed and a thermodynamic model in isolated perfused and superfused canine right or left free wall was established. Different levels of electrical power and acoustic time were adopted and the size of the resulting lesions was measured to observe the dose-response relationship. Lesions resulted by using different levels of power and duration of radiofrequency energy delivery were also observed for comparison. Results There was a linear relationship between the increasing electrical power and the depth of lesion. There were also positive relationships between the lesion area and the sonication time. Electrical power was a better predictor of the lesion depth, while energy is a better physical variable to describe the lesion area. Transducer-tissue contact pressure has no significant effect on the lesion size. The lesion depth of ultrasound ablation was much greater than that of the radiofrequency ablation. Conclusion In comparison with radiofrequency, ultrasound should be able to create the deeper lesions that should be beneficial for the treatment of ventricular tachycardia after myocardial infarction.

关 键 词：超声导管消融术 心肌梗塞 室性心动过速 

分 类 号：R542.220.6[医药卫生—心血管疾病] R541.710.5[医药卫生—内科学]