Whittaker P, Spariosu K, Ho Z Z
Heart Institute, Good Samaritan Hospital, and Department of Medicine, University of Southern California, Los Angeles 90017, USA.
Lasers Surg Med. 1999;24(4):253-60. doi: 10.1002/(sici)1096-9101(1999)24:4<253::aid-lsm1>3.0.co;2-9.
Previous studies of transmyocardial laser revascularization have reported open channels after ultraviolet laser treatment and closed channels with infrared lasers. We speculated that differences in long-term channel patency were determined by the healing response to injury.
Channels were made in rat hearts with a frequency-tripled neodymium:YAG laser, at 5 and 10 mJ per pulse, by advancing an optic fiber through the myocardium, from the epicardium to the ventricular cavity. Several months later, we challenged the ability of the channel to supply blood by arterial occlusion and examined the channel structure with polarized light microscopy.
Low-pulse energy was associated with lower patency, more fibrosis, and larger infarcts than was the higher energy. Open channels were surrounded by collagen fibers aligned parallel to the channel; in closed channels, fibers were aligned perpendicular to the original channel direction.
The amount of initial injury and its repair determine channel patency and function.
以往经心肌激光血运重建术的研究报告称，紫外线激光治疗后通道开放，而红外线激光治疗后通道闭合。我们推测长期通道通畅性的差异是由对损伤的愈合反应决定的。
使用三倍频钕：钇铝石榴石激光，以每脉冲5毫焦和10毫焦的能量，通过将光纤从心外膜推进到心室腔，在大鼠心脏中制造通道。几个月后，我们通过动脉闭塞来挑战通道供血的能力，并用偏光显微镜检查通道结构。
与高能量相比，低脉冲能量与更低的通畅性、更多的纤维化和更大的梗死灶相关。开放通道被与通道平行排列的胶原纤维包围；在闭合通道中，纤维垂直于原始通道方向排列。
初始损伤的程度及其修复决定通道的通畅性和功能。
