Morcos N C, Berns M, Henry W L
Department of Medicine (Cardiology Division), University of California, Irvine 92717.
Lasers Surg Med. 1988;8(1):22-9. doi: 10.1002/lsm.1900080107.
Effects of laser-heated-tip angioplasty on arteries is not fully understood. We report histology, ultrasound image properties, and vasoreactivity of human atherosclerotic coronary arteries after exposure to the laser-heated tip catheter. Segments of isolated human coronary arteries were obtained within 5-8 hours postmortem. Side branches were ligated and perfused with Krebs-Ringer solution. Coronary occlusions were recanalized during perfusion using a 1.5-mm tip heated twice with a 10 W argon laser for 10 seconds while two-dimensional 12-MHz ultrasound images were recorded. Images documented vessel recanalization and an increase in ultrasound refractile properties of vessel walls adjacent and 2-5 mm distal to the heated tip. Histologic studies showed charring along the neolumen and extensive coagulation pattern within the plaque. Vasoreactivity was assessed by measuring flow rate changes during perfusion with 100 ml of 10(-5) M serotonin followed by washout with serotonin-free solution. Recanalized arteries showed a 50% increase in magnitude of vasospasm, which was persistent for 5 hours, compared to control atherosclerotic vessels, which relaxed within 30 minutes. In conclusion, laser-heated-tip-irradiated vessels demonstrated plaque coagulation, increased ultrasound refractile properties of plaque, and increased vasospasm, which persisted for several hours.
激光热头血管成形术对动脉的影响尚未完全明了。我们报告了人体动脉粥样硬化冠状动脉在暴露于激光热头导管后组织学、超声图像特征及血管反应性的情况。在死后5至8小时内获取离体人体冠状动脉节段。结扎侧支并灌注克氏-林格溶液。在灌注过程中，使用10瓦氩激光对1.5毫米的热头加热两次，每次10秒，同时记录二维12兆赫超声图像，以此使冠状动脉闭塞再通。图像记录了血管再通以及热头附近及远端2至5毫米处血管壁超声折射特性的增加。组织学研究显示新管腔内有炭化现象，斑块内有广泛的凝固模式。通过在灌注100毫升10（-5）M血清素期间测量流速变化，然后用无血清素溶液冲洗来评估血管反应性。与在30分钟内舒张的对照动脉粥样硬化血管相比，再通的动脉血管痉挛程度增加了50%，且持续5小时。总之，激光热头照射的血管表现出斑块凝固、斑块超声折射特性增加以及血管痉挛增加，且这种痉挛持续数小时。
