两种激光致心肌血管重建的组织学效应

目的；研究两种激光在心肌血管重建术（TMR）中的组织学效应。方法：实验犬随机分为2组：连续波CO2激光组（n=20）及调制Nd：YAG激光组（n=10），2组均经心外膜法行激光打孔，观察激光孔道的组织学改变。结果：CO2激光孔道周围出现明显的碳化带、凝固性坏死层及心肌变性层，经8周的修复，出现不同程度的微循环改建，尤以碳化程度轻的部位为著；而Nd：YAG激光孔道未见碳化物形成，凝固性坏死及心肌变性范围明显减小，术中并发症的发生均较CO2激光减轻。结论：Nd：YAG激光孔道的热损伤程度轻，有利于心肌内微循环改建，以改善心肌供血，且具有术中并发症少等优点。     

网膜心脏固定术增加缺血心肌激光再血管化的远期疗效

心肌Nd:YAG激光孔道远期均为纤维组织闭塞,采用网膜心脏固定术增加对缺血心肌远期的保护作用。18条杂交犬分为3组:对照组(n=6)、激光心肌再血管化组(n=6)和激光心肌再血管化 网膜心脏固定术组(n=6)。对照组仅结扎左侧冠状动脉前降支的对角支、中间支的第一、二支,及与之相连的左侧回旋支的钝缘支的吻合支,建立动物模型。单纯激光心肌再血管化组:用Nd:YAG激光刀,于左室壁心肌缺血区直接贯穿打孔6～8个,孔间距10mm。网膜心脏固定术组在激光心肌再血管化后,行大网膜经皮下遂道移植于心脏表面。术后4周行放射性同位素~(86)Rb摄取分数,示踪剂检查和心肌组织学活捡。结果显示网膜心脏固定术缺血心肌区远期的放射性同位素~(86)Rb摄取分数增加,网膜—心肌测支血液循环建立。     

1000 W CO_2激光心肌血运重建术对心肌ATP含量影响的实验研究

目的 探讨1000WCO2 激光心肌血运重建术 (TMLR)对缺血心肌血流灌注的影响。 方法 制备绵羊急性心肌缺血模型 ,行1000WCO2 激光TMLR ,并测量TMLR前后心肌ATP的含量。结果 绵羊急性缺血心肌经TMLR后心肌组织ATP含量明显增加 (P<0.01) ,心肌收缩力明显增强。 结论 TMLR能有效改善心肌血流灌注 ,恢复心肌活性 ,从而提高心功能。     

经静脉注射造影剂超声心肌微泡造影观测钬激光及活检针心肌再血管化

目的：研究钬激光和True-cut活检针心肌再血管化的方法,机制及近期效果。方法：经静脉注射造影剂,在心仙缺血前后和再血管化后三个不同时期对犬时期对犬进行心肌超声微泡造影。研究钛激光和True-cut活检针心肌再血管化的机制及观察近期效果。结果：部分结扎犬冠状动脉前降支后,缺血区超声微泡密度明显降低.分别用两种方法再血管化后,缺血区超声微泡密度较缺血时明显增加（P＜0．01）,接近缺血前的微泡密度,再血管化区超声微泡较其它部位提前显影。结论：钬激光和True-cut活检针再血管化均可使缺血心肌灌注即刻改善;再血管化心肌隧道可在收缩期灌注心肌。     

EXPERIMENTAL STUDY OF HOMIUM: YAG LASER TRANSMYOCARDIAL REVASCULARIZATION IN ACUTE ISCHEMIC SET TINGS WITH MYOCARDIAL CONTRAST ECHOCARDIOGRAPHY

ＩＮＴＲＯＤＵＣＴＩＯＮ　　Ｓｅｎ( 1)ｄｅｍｏｎｓｔｒａｔｅｄｉｎ 1965ｔｈａｔｃａｒｄｉａｃａｃｕｐｕｎｃｔｕｒｅｌｅｄｔｏｉｍｐｒｏｖｅｄｐｅｒｆｕｓｉｏｎｏｆｔｈｅｍｙｏｃａｒｄｉｕｍａｎｄｓｕｒｖｉｖａｌｉｎｄｏｇｓａｆｔｅｒｔｈｅａｎｔｅｒｉｏｒｄｅｓｃｅｎｄｉｎｇｃｏｒｏｎａｒｙａｒｔｅｒｙｈａｄｂｅｅｎｌｉｇａｔｅｄ .Ｈｏｗｅｖｅｒ ,Ｐｉｆａｒｅ( 2 )ｆｏｕｎｄｔｈａｔｓｕｃｈｃｈａｎｎｅｌｓｄｉｄｎｏｔｒｅｍａｉｎｐａｔｅｎｔｄｕｅｔｏｅａｒｌｙｆｉｂｒｏｓｉｓ.Ｉｎ 1982 ,Ｍｉｒｈ…     

EXPERIMENTAL STUDY OF HOMIUM： YAG LASER TRANSMYOCARDIAL REVASCULARIZATION IN ACUTE ISCHEMIC SETFINGS WITH MYOCARDIAL CONTRAST ECHOCARDIOGRAPHY

OBJECTIVE: To study the mechanism and effects of blood perfusion to the acute ischemic region of myocardium through Ho-YAG laser channels with myocardial contrast echocardiography. METHODS: To produce the model of acute myocardial ischemia, we partially ligated the left anterior decending (LAD) coronary artery of canine hearts between 1st. and 2nd. diagonal branches and then performed transmyocardial revascularization in this region with Ho - YAG laser. Myocardial contrast echocardiography was made with a new generation of ultrasound contrast agent and second harmonic imaging of this region before, after ischemia and after laser revascularization. Pictures were taken with "R" wave trigger skill. RESULTS: Acoustic density determing in the ischemia region (anterior wall) with MCE (myocardial contrast echocardiography) was obviously decreased (5.40 +/- 1.81) after the LAD was ligated,as compared with before (11.69 +/- 1.61, P < 0.01). It was increased remarkably after transmyocardial laser revascularization (TMLR) (11.2 +/- 2.01, P < 0.01) as compared with that when ischemia and approximated to that before ischemia (P > 0.05). There were no differences in acoustic density in the lateral wall (as control) among these comprehensive three periods (P > 0.05). Contrast in the laser region developed one cardiac cycle ahead of that in the non-ischemic normal region. CONCLUSION: Acute ischemic myocardium can be perfused by oxygenated blood from the left ventricle through Ho - YAG laser channels. Evidence of blood perfusion through laser channels during systolic phase was detected, and myocardial contrast ultrasonography using intravenous perfluorocarbon-exposed sonicated dextrose albumin may be regarded as a reliable method in the study of transmyocardial revascularization.     

COMPARATIVE EXPERIMENTAL STUDY OF HO-YAG LASER AND TRUE-CUT BIOPSY NEEDLE IN MYOCARDIAL REVASCULARIZATION

INTRODUCTION In 1965, Sen (1) demonstrated that cardiac acupuncture using needles led to improved perfusion of the myocardium and survival in dogs after the anterior descending coronary artery had been ligated. However, Pifarre (2) found that such channels did not remain patent due to early fibrosis. In 1982, Mirhoseini (3) applied the concept of transmyocardial revascularization using CO2 laser to patients with coronary artery disease who were not candidates for conventional coronary b…     

Is communication to endocardium necessary for angiogenesis in transmyocardial laser revascularization?

There is evidence of angiogenesis being induced after transmyocardial laser revascularization (TMLR), although the precise mechanism has not been fully elucidated. This study was designed to examine whether or not blood flow from the left ventricle through the channels is essential for angiogenesis following TMLR. Ten dogs underwent the creation of two types of laser channels in the left ventricle: 1) a transmural channel (TMC), which penetrates the myocardium, and 2) a non-transmural channel (NTMC), which does not open to the epicardium. The animals were sacrificed on the 28th postoperative day and the vascular density was examined. Vessels with smooth muscle media were seen within or around the channel remnant. The vessel density was compared between TMC and NTMC. The outer and inner halves of the myocardium in the TMC region were compared in the same way. The density of vessels within and around the channel remnants was significantly higher in TMC than in NTMC (1.439 versus 0.685 vessels/microscopic visual field (mvf=40X); p=0.0025). The vascular density was significantly higher in the region adjacent to TMC than in a distant region (>3 mm from the channel center). The vascular density was significantly higher in the outer half than in the inner half of the myocardium (1.730 versus 1.180 vessels/mvf: p=0.0459). These findings demonstrate that communication to the left ventricular lumen enhances angiogenesis of TMLR, although blood flow in the channel did not exist 4 weeks after TMLR and angiogenesis tended to be more highly enhanced in the outer half than in the inner half of the myocardium.     

血管再生治疗对急性心肌梗塞犬心脏功能的影响

目的 :采用超声心动图心功能测定、组织多普勒显像和血流多普勒频谱技术 ,评价心肌内控制释放碱性成纤维细胞生长因子 (bFGF)血管再生治疗对急性心肌梗塞 (AMI)犬心脏收缩与舒张功能的影响。方法 :18只成年健康杂种犬于开胸后结扎左前降支 (LAD) ,制作AMI模型。动物平均分为 3组 ,单纯心肌梗塞 (MI)组 ,直接关胸 ;激光心肌血运重建 (TMR)组 ,于AMI 30min后行透壁心肌打孔 ;bFGF组 ,于AMI 30min后行非透壁心肌打孔 ,并随后向孔道内注射含有bFGF的纤维蛋白胶 (FG) ,以封闭激光孔道。 8周后行超声心动图检查 ,以评价心脏收缩与舒张功能。结果 :MI组与TMR组于术后 2 2d和 34d各有一只死亡 ,bFGF组无死亡。bFGF组的左心室射血分数 (EF)、每搏出量 (SV)和心输出量 (CO)均明显高于MI组与TMR组 (P均 <0 .0 5 )。bFGF组的左心室面积变化分数 (FAC)明显高于MI组 ,室壁运动指数 (WMI)明显低于MI组 ,但与TMR组相比均无明显差异。尽管采用TMR和bFGF干预后有改善舒张功能的趋势 ,但采用二尖瓣口血流频谱和二尖瓣瓣环的组织多普勒血流显像两种方法测得 3组的E A比值却均无明显差异。结论 :使用FG在心肌内控制释放bFGF进行血管再生治疗安全可行 ,能显著改善急性心肌梗塞犬的收缩功能 ,但对梗塞心脏的舒张功能改善不明显?     

激光心肌血运重建术围手术期及早期临床观察

目的：观察激光心肌血运重建术围手术期及早期临床疗效。方法：4例病人，左前外侧开胸，用国产CO2激光器在左心室前、侧、后壁上，打出15～30个小孔，以改善缺血心肌的血供。结果：3例病人心绞痛和心功能明显改善。1例病人改善不理想，与原有疾病（二尖瓣及主动脉瓣关闭不全，心功能不全，持续性低血压）有关。结论：激光心肌血运重建术对晚期冠心病是一种新的治疗手段，它能改善心肌供血，缓解心绞痛，改善心功能。     

高龄高危患者激光心肌血运重建术

采用美国PLC产CO2 激光心脏打孔器 ,对 33例高龄 ( 68～ 78岁 )冠心病心绞痛患者在食管超声心动图(TEE)监测下行心肌打孔 [平均打孔 ( 2 2± 5)个 ]。结果 :无手术死亡 ,术后 4 8h内因急性心肌梗死死亡 2例 ,因心源性休克 (原因不明 )死亡 1例 ;少数患者发生心律失常、精神症状、自发性气胸等并发症。 2 6例患者术后随访 1～ 36月 ,其中 2 3例 ( 88% )患者心绞痛改善或消失 ;1 6例 ( 62 % )单光子发射型计算机断层显示心肌灌注有不同程度改善。提示 :应用高功率CO2 激光对高龄高危冠心病患者行激光打孔心肌血运重建术安全、有效 ;并应加强围术期管理     

经皮激光心肌血运重建术治疗心肌缺血机制的实验研究

目的　探讨经皮激光心肌血运重建术 (PMR)治疗心肌缺血的机制。方法　取体重 14～18kg的雄性杂种健康犬 10条 ,随机分为PMR组和对照组 ,每组 5条。对两组犬均以不完全结扎冠状动脉 (冠脉 )左前降支的方法复制慢性心肌缺血模型。PMR组在冠脉结扎术后 2周采用Ho :YAG激光系统在缺血心壁施行PMR ,每条犬平均打孔 (15± 3)个。PMR组在冠脉结扎前和PMR后 1、4、12周 ,对照组在冠脉结扎前、冠脉结扎后 3、6和 14周 ,以心肌核素显像检查心肌灌注状况 ,以超声心动图测量左室射血分数 (LVEF)。PMR组在 1、4周检测结束后各处死 1条犬 ,12周检测结束后处死 3条犬 ;对照组在 14周检测结束后处死全部 5条犬。取犬心肌组织作形态学观察及血管计数。PMR术后 2 4h病理标本取自PMR预实验犬。结果　 (1)心肌灌注积分 :PMR组冠脉结扎前为 3 2± 0 6 ,PMR后 12周为 0 3± 0 2 ;对照组冠脉结扎前为 3 1± 0 5 ,结扎后 14周为 1 2± 0 3。两组下降幅度的差异有显著意义 (P <0 0 5 )。 (2 )LVEF :PMR组冠脉结扎前为 4 2 6± 6 5 ,PMR后 12周为 5 5 8± 7 6 (P <0 0 5 ) ;对照组冠脉结扎前为 4 3 2± 8 7,结扎后 14周为 4 5 2± 6 3。两组增加幅度的差异有显著意义 (P <0 0 5 )。 (3)PMR犬心肌PMR区域每视野微血管     

冠状动脉搭桥加激光心肌血管重建术临床应用(附1例报告)

目的：探索更好的治疗冠心病途径，临床应用冠状动脉搭桥同期施行激光心肌血管重建术。方法：在冠状动脉搭桥手术中，应用激光心肌打孔。结果：术后10天心肌核素扫描示心肌缺血明显改善。结论：该方法安全、有效，值得应用和深入研究。     

13例冠状动脉旁路术的临床分析

目的 报告13例冠状动脉旁路术的临床体会。方法 体外循环下手术9例。非体外循环心脏跳动下手术4例,其中3例同期行心肌激光血运重建术,单支病变2例、双支病变3例、三支病变7例、左主干病变1例。平均每例搭桥2.3支。结果 全组无手术死亡,术后心绞痛消失11例,减轻2例。结论 冠状动脉旁路术是安全的手术,非体外循环心脏跳动下冠状动脉旁路术可减少术后输血及并发症,患者术后恢复快。     

Angiogenesis effects of adenovirus—mediated gene transfer of VEGF—B on chronic ischemic myocardium

Objective: To study the angiogenesis effects of adenovirus-mediated gene transfer of VEGF-B on chronic ischemic myocardium. Methods: Domestic pigs underwent thoracotomy and placement of an ameroid constrictor on the circumflex coronary artery. Four weeks later, Ad. VEGF-B, Ad. LacZ or PBS were administrated directly into the myocardium at 10 sites in the circumflex distribution (109 PFU or 100 μl) according to groups. Echocardiography and ex vivo coronary angiography were performed. The injection sites around myocardium were harvested and subjected to histological analysis and immunochemical staining. Results: E-chocardiography assessment 4 weeks after vector administration demonstrated significant improvement of regional wall systolic function. Collateral vessel development assessed by angiography was also significantly greater in Ad. VEGF-B animals than that in control animals. Vascular density analysis revealed a mean of 43±5 neovessels per high-power field in Ad. VEGF-B group versus 19±4 and 17±6 in     

A COMPARATIVE STUDY ON CELLULAR ELECTROPHYSIOLOGIC CHANGES BETWEEN LASER PHOTOCOAGULATION AND RADIOFREQUENCY ABLATION

ＩＮＴＲＯＤＵＣＴＩＯＮＴｒａｎｓｖｅｎｏｕｓｃａｔｈｅｔｅｒａｂｌａｔｉｏｎｈａｓｂｅｃｏｍｅａｎｅｆ－ｆｅｃｔｉｖｅｍｅｔｈｏｄｆｏｒｔｒｅａｔｍｅｎｔｏｆｔａｃｈｙａｒｒｈｙｔｈｍｉａｓ．Ｈｉｇｈｅｎｅｒｇｙｅｌｅｃｔｒｉｃａｌａｂｌａｔｉｏｎ...     

LDH与MDH在大鼠角膜碱烧伤中的表达及在能量代谢中的意义

目的：研究乳酸脱氢酶同工酶(LDH)、苹果酸脱氢酶同工酶(MDH)在大鼠角膜碱烧伤后的表达特点及它们之间的相关性，以探讨其对碱烧伤后能量代谢变化的影响。方法：用醋酸薄膜电泳法测定LDH、MDH同工酶的含量，以探讨碱烧伤后能量代谢的变化特点。结果：对LDH、MDH同工酶的百分含量进行扫描，结果发现同工酶百分含量明显改变。碱烧伤初期LDH，、LDH2、LDH3和LDH4下降，LDH5上升；当第7～10d时LDH5逐渐恢复正常水平。MDH1、MDH2与正常组比较无显著性差异，MDH3与正常组比较有显著性差异。结论：碱烧伤后，由于免疫炎症反应的影响，使参与角膜能量代谢反应的酶含量发生改变，从而使能量代谢的状态也随之发生改变。MDH1、MDH2和LDH5活性增强，导致无氧糖酵解增强，代偿能量的不足．弥补角膜碱烧伤后整个病理过程对能量的需求。     

激光打孔心肌血运重建术新进展

激光心肌血运重建术(TMIR)是利用激光在缺血的左心室壁制造多个心肌隧道,以促使心腔内的氧合血经隧道注入心肌内,并通过心肌大量的窦状隙及冠状动脉交通网营养该区域心肌。在60年代用针穿刺左心室壁造成孔道改善心肌缺血的基础上Mirhoseini等在70年代末开始了TMLR的实验研究。80年代围绕TMLR的组织学、生理学、生物物理学等方面的研究报道较多,低功率二氧化碳激光TMLR作为冠脉搭桥(CABG)的辅助方法也开始用于临床。90年代在高功率二氧化碳激光成功地用于人心脏跳动下心肌打孔手术后,TMLR成为单独治疗晚期重症冠心病的另一种新方法。1994年尸检发现了激光孔道长期通畅并内皮化及与周围心肌血窦相沟通的组织学证据。近年来,有关TMLR在(1)促进血管内皮生长方面的实验研究,(2)用磁共振成像(MRI)、单光子发射计算机断层(SPECT)和正电子断层扫描(PET)、心肌造影超声(MCE)等手段进行临床随访,(3)临床开展的心脏搏动条件下CABG结合TMLR,(4)TMLR术式及其适应证的选择等实验与临床应用方面均有很大进展。     

Nd:YAG激光照射鼓膜对听觉功能影响的实验研究

目的 :探讨不同功率Nd :YAG激光照射鼓膜对内耳结构和功能的影响。方法 :应用光纤末端功率为 8W、6W、4W的Nd :YAG激光针对豚鼠作鼓膜照射 2s。采用听性脑干反应、耳蜗基底膜铺片及扫描电镜技术 ,观察激光照射前后 (分即刻及饲养 2周后 )ABR阈值及形态学变化。结果 :所用激光功率与内耳损伤程度成正相关 ,3组ABR阈值在即刻和饲养 2周后均升高 ,8W、6W组均较 4W组升高明显 ,8W、6W组照射后 2周ABR阈值较照射前差异有显著性 (P <0 .0 5 ) ,但 4W组 2周后恢复明显 ,与照射前差异无显著性。照射后立即取材的耳蜗毛细胞形态改变的结果 :即刻 8W、6W组耳蜗外毛细胞出现肿胀 ,硝酸银浓染 ,血管纹血管扩张 ,4W组无明显改变。饲养 2周后 ,8W组外毛细胞平均损失达 45 % ,6W组平均损失 2 0 % ,以上两组内毛细胞亦有少量缺失 ,4W组内、外毛细胞形态基本正常。结论 :本实验提示 :采用Nd :YAG激光治疗中耳疾病时 ,其光纤末端输出功率应控制在 4W ,时间为 2s为宜 ,否则可能会导致不可逆的听力下降。     

激光心肌再血管化的实验研究

采用激光心肌血管重建术的方法对动物实验模型缺血性心脏病的治疗进行探讨。杂交犬３４条分为３组：对照组１０条、激光心肌血管重建术组８条，激光心肌血管重建＋心脏网固定术组１６条。分别监测了ＥＫＧ（ＳＴ－Ｔ）、心输出量、放射性同位素＾８６Ｒｂ摄取分数和组织学检查等。结果显示激光打孔后ＳＴ－Ｔ改变恢复、心输出量增加、心肌血供增加，以激光光心甩血管重建术＋心脏网膜固定术组。组织学检查发现激光孔道２周后被纤维组