【作者】 刘闯；

【导师】 董建增； 李凌；

【作者基本信息】 郑州大学 ， 心血管内科， 2004， 硕士

【摘要】 目的 本研究采用一种新技术标测犬Marshall韧带(LOM)，目的是阐明犬LOM的电生理学特性，探讨LOM与左心房、冠状静脉窦、左肺静脉电学关系及无水乙醇消融LOM近端冠状静脉窦入口处对LOM电位的影响。 方法 健康杂种犬19只，体重15～21 kg，雌雄不拘，由郑州大学动物实验中心提供。戊巴比妥钠肌肉注射全身麻醉及机械通气(30 mg／kg)，左侧第4肋间侧胸开口或胸部正中开口。切开心包，制作心脏吊篮，清楚显露LOM及其周围结构。 应用自制10极生物电梳状标测电极(极间距2mm，电极直径0.1mm，镀银)和钩状标测电极(极间距2mm，电极直径0.1mm，镀银)进行LOM心外膜标测。标测时生物电梳状标测电极(梳状电极)平行重叠于LOM，第1极指向LOM左上肺静脉端(LOM上端)，第10极位于LOM与冠状静脉窦远段连接处(LOM下端)；完成标测后，应用计算机自动标尺系统测量梳状电极不同电极对LOM电位与心房电位间期；然后梳状电极平行于LOM并分别向左心耳侧及左肺静脉侧平移2 mm、5 mm记录，进而平行贴靠于冠状静脉窦，第10电极位于冠状静脉窦口侧，第3、4、5电极横跨LOM与冠状静脉窦交汇处记录。同步记录体表Ⅱ导联心电图和9道双极心外膜电图。随后分别行S1S1程序刺激梳状电极1极并单纯夺获LOM上端、刺激左心耳、刺激左上肺静脉、无水乙醇消融LOM冠状静脉窦入口处(必要时消融LOM中段与左心房连接处)，观察同步记录体表Ⅱ导联心电图和9道双极心外膜电图变化。 对其中6只犬剪断LOM近中段，观察剪断前后LOM电位变化及LOM有效不应期变化。郑州大学2004届硕士研究生毕业论文犬M盯shafl韧带与左心房的电学关系 将梳状电极不同电极对LOM电位与心房电位间期进行统计学分析;将剪断前后LOM有效不应期进行对比并作统计学分析处理，以a=0 .05为检验水准。 结果 1:LOM电位记录率:19只犬中，17只犬一记录到了LOM电位，记录率为89.5% (17/19)。 2:LOM双极心外膜电图特征:窦性心律时，心房波从上至下逐渐拖后，而LOM电位从上(上端)至下(下端)逐渐提前，在LOM的冠状静脉窦入口处二者融合形成典型“v”字形， LOM电位位于冠状静脉窦A波的终末部或与其完全融合，呈这种典型“V”字形者占58.8%(10/17);或LOM电位自中段至下段激动时间相差不大，甚至中段略早于下段，与心房波构成不典型“V”字形，类似“Y”字形或“K”字形，呈这种不典型“V”字形者占41.2%(7/l7)。在17只记录到LOM电位的犬中，均可在平行于LOM之外Slnm区域内记录到LOM电位。 3:LOM下端与冠状静脉窦的电学关系:94.1%(16/ 17) LOM与冠状静脉窦之间双向传导。于平行于冠状静脉窦方向上，在LOM冠状静脉窦入口处可一记录到LOM电位的宽度为4一Slnm。 4:无水乙醇化学消融LOM前后LOM电位的变化:在13只拟行无水乙醇化学消融LOM的犬中，消融前有n只犬可经心外膜沿LOM全程一记录到LOM电位，其中对于9只LOM心外膜生物电梳状电极同步9道双极记录呈“V”字形的犬，仅局限在LOM冠状静脉窦入口处一点消融即可使LOM电位全部消失，实现电学隔离LOM;对于2只LOM心外膜生物电梳状电极同步9道双极一记录呈“Y”字形的犬，需同时在LOM冠状静脉窦入口和LOM中段电位提前处左心房游离壁入口两点无水乙醇化学消融方可使LOM电位全部消失，从而实现LOM的电学隔离。 5:剪断前LOM有效不应期和剪断后断端冠状静脉窦侧有效不应期无明显变化(5 152=400/115.00士7.O7mS VS 400/115.83士3.76ms，P)0.05) 结论应用自制10极生物电梳状电极可以清楚显示LOM与左心房、冠状静脉窦电学关系及LOM的激动顺序。9道双极心外膜记录呈“V”字形者LOM与左心房仅在LOM冠状静脉窦入口处一点存在电学联系;9道双极心外膜一记录呈“Y”字形者LOM与左心房不仅在LOM冠状静脉窦入口处而且在左心房后下壁这两点存在电学联系。更多还原

【Abstract】 Objective: Epicardial mapping of LOM was performed by a home-made comb-like mapping catheter, to elucidate electrical characters of ligament of Marshall (LOM) and it’ s relationship with left atria, coronary sinus (CS), left pulmonary veins and to evaluate the effects of chemical ablation to LOM potential,.Methods: A total of 19 normal dogs with both genders (weight 15-21 kg )were adopted in this study . After general anesthesia with sodium pentobarbital (30mg/kg im) (stop feeding 12 hours before procedures), these animals were intubated and mechanically ventilated with a pressure-controled ventilator. A left intercastal space thoarecotomy was performed, and 1 or 2 ribs were removed according to the degree of exposure. Pericardium was opened to cradle the heart. Then the LOM and pulmonary veins were clearly exposed. Epicardial mapping of the LOM was registered with comb-like mapping catheter closely paralleling to the LOM near left super pulmonary vein and the tenth pole was laid over CS entrance of LOM. Then the comb-like mapping catheter was paralleled to LOM and moved to left atrial appendage (LAA) or left pulmonary veins for about 2 mm and 5 mm respectively. Then the comb-like mapping catheter was paralleled toCS and the tenth pole was located to the orifice of CS. S1S1 programmed stimulations were applied to the first electrode of the comb-like mapping catheter, LAA, LSPV respectively and chemical ablation was applied to the CS entrance of LOM. Every procedure was accompanied by synchronously recording of surface ECG (lead II) and 9-channel, bipolar epicardial electrogram.LOMs of six dogs were cutted off from mid segments to observe the changes of LOM potential and effective refractive period of LOM before and after cutted off respectively.The effective refractive period of LOM was compared and statistically analyzed before and after the cutting off and a =0. 05 was considered as significance level.Results:1. Registrable rate of LOM potential: LOM potential in 17 dogs could be registered among the 19 dogs and the registrable rate is about 89. 5 percents (17/19).2. Characteristics of bipolar epicardialgram of LOM: Every bipolar epicardial gram consists of corresponding left atrial potential and LOM potential .The left atrial potential of 10 bipolar epicardialgrams gradually delay from top to bottom under sinus rhythm. LOM potentials gradually precede from top to bottom in 10 dogs . So at the CS entrance of LOM, the typical "V" figure was composed by the left atrial potential and the LOM potential. In another 7 dogs, the LOM potentials gradually precede from top to bottom. But the earliest LOM potential is recorded at both at the middle segment and at the CS entrance of LOM. So atypical"V" shape (like "Y" ) was presented. The synchronously recorded 9 channels epicardialgram along the LOM presented as a typical "V" figure in 58. 8% (10/17) and presented as an atypical "V" figure in 41. 2% (7/17).3. Electrical relationship between LOM and CS: Double directionelectrical conduction were presented in 94. 1%(16/17). The width of recordable region of LOM potential was about 4~8mm at the CS entrance of LOM.4. Comparison of the LOM potential’ s changing by alcohol ablation: The LOM potential could entirely disappeared by injecting alcohol only to the CS entrance of LOM in 9 dogs whose LOM bipolar epicardiogram were"V" figure among 11 consecutive dogs intervened by ablation with injection of alcohol. Then the electrical isolation of LOM was realized and the success rate of first ablation was 77. 8%. For another 2 dogs whose LOM bipolar epicardiogram were "Y" figures, the electrical isolation could not be realized by the alcohol ablation at the CS entrance of LOM, it should be realized together by the ablation to the middle segment of LOM (left atrial free wall entrance of LOM). The total successful rate of alcohol ablation can achieve 100 percent.5. The effective refractive period of LOM has no change before and after the cutting off (S1S2=400/115. 00 + 7. 07ms VS 400/115. 83 + 3. 76ms, P>更多还原