Abela G S
Division of Cardiology, University of Florida, Gainesville.
Thorac Cardiovasc Surg. 1988 Jun;36 Suppl 2:137-41. doi: 10.1055/s-2007-1022989.
Inspite of the effectiveness of PTCA and surgery in the treatment of occlusive vascular diseases, still a number of patients remain untreatable by these methods. Laser light with its ability to ablate tissue and to be delivered even in small distal branches of the vascular tree seemed to offer a new perspective. The interaction between laser light and tissue is determined by special physical characteristics. Up till now none of the available laser systems are optimal for application in the cardiovascular system, but still many of them have been effective clinically. One common complication was the high perforation rate by the use of flexible quarz fibers which could not be visualized by fluoroscopy. The addition of a small metal ring and later-on of a metal cap covering the end of the fiber showed significant improvements. Not only could those fibers be visualized by a fluoroscopy, but could convert laser energy into thermal energy. The perforation rate was decreased and a greater size channel created. Lately the introduction of a small saphir window at the tip of the metal cap offered the combined application of light and thermal energy. Animal studies demonstrated these advantages with a low perforation and a high penetration rate of atherosclerotic material. Clinical studies also revealed good results and a significantly lower perforation rate with the metal capped probe. Using the probe with a small saphir window at its tip, the success rate in totally occluded peripheral vessels, not treatable by conventional PTCA, was 82%. As the newly created channel showed a sufficient diameter.(ABSTRACT TRUNCATED AT 250 WORDS)
尽管经皮腔内冠状动脉成形术(PTCA)和手术在治疗闭塞性血管疾病方面具有有效性,但仍有一些患者无法通过这些方法进行治疗。激光能够消融组织,甚至可以作用于血管树的细小远端分支,这似乎提供了一个新的视角。激光与组织之间的相互作用由特殊的物理特性决定。到目前为止,现有的激光系统中没有一种是最适合应用于心血管系统的,但其中许多在临床上仍然有效。一个常见的并发症是使用可弯曲石英纤维时穿孔率高,而荧光透视无法看到这些纤维。添加一个小金属环以及后来在纤维末端覆盖一个金属帽显示出显著改善。这些纤维不仅可以通过荧光透视看到,而且可以将激光能量转化为热能。穿孔率降低了,并且形成了更大尺寸的通道。最近,在金属帽尖端引入一个小蓝宝石窗口实现了光和热能的联合应用。动物研究证明了这些优势,即穿孔率低且动脉粥样硬化物质的穿透率高。临床研究也显示出良好的结果,并且使用带金属帽的探头时穿孔率显著降低。使用尖端带有小蓝宝石窗口的探头,在传统PTCA无法治疗的完全闭塞外周血管中的成功率为82%。因为新形成的通道显示出足够的直径。(摘要截断于250字)