Hirao K, Yamamoto N, Toshida N, Nawata H, Ishihara N, Suzuki F, Miyasaka N, Hiejima K, Tanaka M
First Department of Internal Medicine, School of Medicine, Tokyo Medical and Dental University, Japan.
Jpn Circ J. 1997 Aug;61(8):695-703. doi: 10.1253/jcj.61.695.
The feasibility of transcatheter laser ablation of the canine left ventricle (LV) was tested using a newly developed cardioscope. In 17 anesthetized dogs, a combined laser-endoscope catheter, consisting of an endoscope encased in a 7-French flexible catheter with an inflatable and transparent balloon at the distal end, was introduced into the LV via the carotid artery. A 1064-nm neodymium-yttrium-aluminum-garnet (Nd:YAG) laser was delivered by laser optic fiber, which was introduced through the transport channel and positioned inside the saline-filled balloon. In 16 of 17 dogs, the endocardial surface of the LV was clearly observed. Laser energy totaling 500-5,000 J was applied sequentially in 13 dogs and laser irradiation was completed in all but 2 of the dogs. The excised hearts revealed well-demarcated oval-shaped lesions 2.5-9.5 mm deep in 7 of 11 dogs. Histologic sections revealed coagulation necrosis surrounded by a rim of contraction band necrosis. Thus, transballoon laser photocoagulation of the beating LV is feasible. The newly combined laser-endoscope catheter, which is still in its preliminary stages and needs to be improved to increase the success rate of photocoagulation, appears to be a promising alternative modality for catheter ablative therapy for ventricular tachycardia.
使用一种新开发的心脏内窥镜测试经导管激光消融犬左心室（LV）的可行性。在17只麻醉犬中，通过颈动脉将一种组合式激光 - 内窥镜导管引入左心室，该导管由包裹在7法国柔性导管中的内窥镜组成，其远端有一个可充气的透明球囊。一根1064纳米的钕 - 钇 - 铝 - 石榴石（Nd:YAG）激光通过激光光纤传输，该光纤通过输送通道引入并置于充满盐水的球囊内。在17只犬中的16只中，清晰观察到左心室的心内膜表面。13只犬依次施加了总计500 - 5000焦耳的激光能量，除2只犬外，所有犬的激光照射均完成。切除的心脏显示，11只犬中有7只出现了界限清晰、深度为2.5 - 9.5毫米的椭圆形病变。组织学切片显示凝固性坏死周围有一圈收缩带坏死。因此，对跳动的左心室进行经球囊激光光凝是可行的。这种新的组合式激光 - 内窥镜导管仍处于初步阶段，需要改进以提高光凝成功率，它似乎是一种用于室性心动过速导管消融治疗的有前景的替代方式。
