急性心肌梗死区KTP激光心肌血运重建术激光孔道演变规律的实验研究

Laser Channel Changes After Transmy ocardial Laser Revascularization with Frequency-double Nd∶YAG Laser in Canine with Acute Myocardial Infarction

目的研究急性心肌梗死犬行KTP激光心肌血运重建术后激光孔道演变规律,探讨KTP激光心肌血运重建术的作用机制。方法结扎犬左前降支中段造成急性心肌梗死模型,在梗死区行KTP激光心肌血运重建,于术后第1、2和3个月取心脏行组织学及免疫组化检查。结果术后第1个月,激光孔道部分通畅,孔道内有大量成纤维细胞、胶原纤维和新生的毛细血管,血管内充满红细胞;术后第2个月,激光孔道大部分被胶原纤维充填,有较多的新生的毛细血管,血管内充满红细胞;术后第3个月,激光孔道基本被胶原纤维充填,只有少量的毛细血管。Ⅷ因子抗原免疫染色标记激光孔道内血管结果显示,术后第1个月每高倍视野的血管记数和血管面积最大,术后第2、3个月,血管记数和血管面积进行性减少。结论KTP激光孔道早期具有血运功能,可能是KTP激光心肌血运重建术作用机制之一;但KTP激光孔道不能保持长期通畅。

Objective To observe the laser channel changes after transmyocardial laser revasc ularization(TMLR)with frequency-double Nd∶YAG laser on acute infarcted myocardium in canine and to understand the mechanisms of TMLR.Methods Left thoracotomy was performed in 9a dult mongrel dogs.The medius of the l eft anterior descending artery(LAD)was ligated to creat the acute myocardia l infarction.Transmyocardial revascularization was performed with fr equency-double Nd∶YAG laser in the acute infarcted LAD territory.The dogs were sacrificed one,two or three months later,respectively.T he changes in the laser channels were observed under the mic roscope.Results The laser channels were partially patency and neovascularization one mo nth after TMLR;they were neovascula rization two months after TMLR;and they were not patency but infiltrated with fibrosis three months after TMLR.The vascul ar number and vascular area are less in 2or 3month-group than in 1month-group.Conclusions The laser channels with frequency-d ouble Nd∶YAG laser improved myocard ial perfusion during the early term b ut not patency in long term.