He D S, Zimmer J E, Hynynen K, Marcus F I, Caruso A C, Lampe L F, Aguirre M L
Department of Medicine, University of Arizona, College of Medicine, Tucson, USA.
Eur Heart J. 1995 Jul;16(7):961-6. doi: 10.1093/oxfordjournals.eurheartj.a061031.
Ultrasound is a potential energy source for cardiac ablation. Small ultrasound applicators were tested for their ability to create lesions in cardiac tissue. Ultrasound applicators were designed, constructed and tested in canine cardiac tissue in degassed normal saline, and both in vitro and in vivo, lesions were produced by using transducers with frequencies of about 10 MHz. Lesion depth increased with longer duration of energy delivery from 15-60 s, and there was a linear relationship between increasing power and depth of lesions. Seven in vivo experiments in open-chest dogs were performed, and the ultrasound transducers were mounted on the tip of 7-French angiographic catheters. On the epicardium the maximum lesion depth was 9 mm. When the transducer was inserted into the left ventricle, lesions of 8.7 +/- 2.9 mm (n = 4) were produced. It is concluded that an ultrasound transducer mounted on a cardiac catheter can produce lesions that may be useful for ablation of cardiac arrhythmias.
超声是一种用于心脏消融的潜在能量源。对小型超声施加器在心脏组织中产生损伤的能力进行了测试。设计、制造了超声施加器，并在脱气的生理盐水中的犬类心脏组织中进行了测试，在体外和体内，使用频率约为10兆赫的换能器都能产生损伤。随着能量传递持续时间从15秒增加到60秒，损伤深度增加，且功率增加与损伤深度之间存在线性关系。对开胸犬进行了七次体内实验，将超声换能器安装在7F血管造影导管的尖端。在心外膜上，最大损伤深度为9毫米。当换能器插入左心室时，产生了8.7±2.9毫米（n = 4）的损伤。得出的结论是，安装在心脏导管上的超声换能器能够产生可能对消融心律失常有用的损伤。
