Weber H P, Heinze A, Enders S, Ruprecht L, Unsöld E
1. Medical Department, Harlaching Hospital, Munich, Germany.
Eur Heart J. 1994 Jul;15(7):971-80. doi: 10.1093/oxfordjournals.eurheartj.a060618.
The feasibility of transcatheter laser coagulation of atrial myocardium was tested in a canine model by using a combined electrode-laser catheter. In 17 anaesthetized beagles a total of 264 lesions, 12-19 per dog, and 3-5 in each area were produced in: (1) the lateral walls, (2) the posterior right atrial walls, (3) the inter-atrial septum, and (4) the atrial appendage. The power source was a continuous wave Nd:YAG laser. Irradiance was 1 kW.cm-2, at a wave length of 1064 nm, the irradiated spot diameter was 2.0-2.5 mm, and the pulse duration 5-60 s. Local intra-cardiac atrial potentials recorded from the targeted areas during laser irradiation dwindled after onset of the laser pulse, and their amplitude was reduced persistently by pulses of 15 s or longer. Histopathologically, the acute lesions showed intramural haemorrhage and coagulation necrosis, but there was no tissue vaporization or crater formation. Chronic lesions showed clear-cut oval-shaped areas of transmural fibrosis. Diameters of lesions, dependent on the amount of laser energy applied, measured from 4.6 +/- 0.5 mm (450 J) to 7.8 +/- 1.4 mm (1800 J). Follow-up lasted 6-25 months (average 10.5). All the animals survived the procedure without complications. Transcatheter laser coagulation of atrial myocardium is safe and can be performed in a controllable manner by using the catheter system presented.
采用联合电极激光导管，在犬模型中测试经导管激光凝固心房心肌的可行性。在17只麻醉的比格犬身上，在以下部位共产生了264个病灶，每只犬12 - 19个，每个区域3 - 5个：(1) 侧壁，(2) 右心房后壁，(3) 房间隔，(4) 心耳。电源为连续波Nd:YAG激光。辐照度为1 kW·cm-2，波长为1064 nm，照射光斑直径为2.0 - 2.5 mm，脉冲持续时间为5 - 60 s。激光照射期间从目标区域记录的局部心内房电位在激光脉冲开始后逐渐减弱，15 s或更长时间的脉冲使其幅度持续降低。组织病理学上，急性病灶表现为壁内出血和凝固性坏死，但无组织汽化或火山口形成。慢性病灶表现为清晰的透壁纤维化椭圆形区域。病灶直径取决于施加的激光能量，范围为4.6±0.5 mm（450 J）至7.8±1.4 mm（1800 J）。随访持续6 - 25个月（平均10.5个月）。所有动物手术过程中均存活且无并发症。经导管激光凝固心房心肌是安全的，使用所介绍的导管系统可以以可控方式进行。
