Kohmoto T, Fisher P E, Gu A, Zhu S M, Yano O J, Spotnitz H M, Smith C R, Burkhoff D
Department of Surgery, Columbia University, New York 10032, USA.
Ann Thorac Surg. 1996 Mar;61(3):861-8. doi: 10.1016/0003-4975(95)01134-X.
Early reports indicate that transmyocardial laser revascularization improves symptoms in patients with refractory angina. However, there is little experimental evidence of whether blood flow through channels is the mechanism of action.
Endocardial channels were made in the distribution of the left anterior descending coronary artery in canine hearts (n = 5) using a holmium:yttrium-aluminum garnet laser. Hearts were excised acutely while perfused in a retrograde fashion from a second dog so that the aortic valve always remained closed. The proximal left anterior descending coronary artery was ligated. To measure direct transmyocardial blood flow, colored microspheres were injected into the left ventricular chamber.
The number of spheres per gram of tissue in the channel region was significantly higher than in the control region (low load, 302.5 +/- 169.0 versus 41.8 +/- 59.4; high load, 208.4 +/- 138.3 versus 5.8 +/- 11.7; both, p < 0.05). However, the estimated regional blood flow through the channels was extremely low (<0.01 mL/g/min. In the chronic setting (n = 4) (2-week survival), no flow as detected through the channels, and the endocardial entry points were closed.
Transmyocardial blood flow does not appear to occur through channels made with the holmium:yttrium-aluminum garnet laser. It remains to be determined whether this is the case with other types of lasers.
早期报告表明，心肌激光血运重建术可改善顽固性心绞痛患者的症状。然而，关于经通道血流是否为其作用机制，几乎没有实验证据。
使用钬：钇铝石榴石激光在犬心（n = 5）的左前降支冠状动脉分布区域制作心内膜通道。在从另一只犬逆行灌注的同时急性切除心脏，以使主动脉瓣始终保持关闭。结扎左前降支冠状动脉近端。为测量直接心肌血流，将彩色微球注入左心室腔。
通道区域每克组织中的微球数量显著高于对照区域（低负荷，302.5±169.0对41.8±59.4；高负荷，208.4±138.3对5.8±11.7；两者，p < 0.05）。然而，经通道估计的局部血流极低（<0.01 mL/g/min）。在慢性情况下（n = 4）（存活2周），未检测到经通道的血流，且心内膜入口点已闭合。
钬：钇铝石榴石激光制作的通道似乎不会出现心肌血流。其他类型的激光是否如此仍有待确定。
