人心和山羊心脏上、下腔静脉肌袖大体解剖

目的:观测人和山羊上、下腔静脉肌袖结构特点,为治疗局灶性心房颤动积累解剖学资料。方法:采用大体解剖方法观测人心(20例)和羊心(40例)的上、下腔静脉及其表面的心肌纤维。结果:人心上腔静脉肌袖的长和宽分别为(1.91±0.39)cm、(2.41±0.26)cm,下腔静脉肌袖的长和宽分别为(1.32±0.32)cm,(3.06±0.52)cm;羊心上(前)腔静脉肌袖的长和宽分别为(1.41±1.00)cm、(1.05±0.26)cm,下(后)腔静脉肌袖的长和宽分别为(0.81±0.48)cm,(1.03±0.28)cm。人和羊心脏的上腔静脉肌袖出现率均为100%;下腔静脉肌袖的出现率分别为88.89%和98%。肌纤维多数来源于右心房前后壁,也有来自于左心房或左右心房的。结论:①上腔静脉肌袖是人和羊普遍存在的解剖结构,人的下腔静脉肌袖出现率明显低于羊,可能是上腔静脉肌袖引起局灶性心房颤动多于下腔静脉肌袖的解剖学基础。②上腔静脉肌袖是构成左右房的又一重要通路。     

家猪心上、下腔静脉心肌袖的形态学观测及临床意义

目的观测家猪上、下腔静脉心肌袖结构及特点,为认识局灶性心房颤动积累比较解剖学资料.方法解剖35例家猪心脏,充分显示上、下腔静脉心肌袖,观测其形态,厚度和长度.结果家猪上、下腔静脉近心端的表面有肌纤维绕行,出现率为100%.上、下腔静脉心肌袖长度分别为(36.93±5.17)mm,(18.76±4.98)mm;心肌袖厚度分别为(1.93±0.69)mm,(1.02±0.35)mm.结论上、下腔静脉心肌袖是家猪普遍存在的解剖结构,是连接左右心房的又一重要通路,可视为制作局灶性心房颤动理想的实验动物模型.     

胎儿心脏连接蛋白43的表达

目的:研究胎儿心脏不同部位连接蛋白43(Cx43)的表达。方法：应用SP免疫组化方法和图像处理系统，分析和比较胎儿心脏不同腔室心肌细胞Cx43的表达。结果：(1)胎儿心脏Cx43的蛋白表达在心脏4个腔均有，呈斑点状遍布于整个心房肌和心室肌的细胞质内和细胞膜表面，少数位于闰盘处。(2)Cx43主要在心室肌表达，心房较少。左、右心房肌和房间隔之间及左、右心室肌和室间隔之间的分布相似。结论：胎儿心脏Cx43蛋白表达主要分布于心肌细胞质内和细胞表面。心室表达多于心房，这种差异可能与胎儿期心房和心室之间功能差异有关。     

国人不同年龄组心肌袖和肺静脉壁的形态学

目的：探讨正常人群不同年龄的心肌袖和肺静脉壁的形态学特征,为房颤的发生及其消融治疗术提供形态学依据。方法：观察不同年龄组心脏的肺静脉周径,并用不同的方法进行切片染色、计算机软件对肌袖周径和面积进行测量比较。结果：肺静脉的周径、肌袖的面积在不同年龄有显著差异,组内各静脉间则无。肌袖的肌纤维以不同的走行方向渐变地从左心房延续至肺门。静脉壁和肌袖面积在中年组和老年组内有显著差异。在老年组内可见肌袖多有纤维化改变、弹力纤维减少和静脉壁较薄,中青年组相反。结论：正常肺静脉的心房-静脉交界处的周径、肌袖和组织构造会随着年龄的改变而变化,这种改变可能与房颤发生的病理学机制及与其消融治疗术有关。     

颈部迷走神经干低频刺激对SD大鼠房颤模型的抑制作用

目的研究颈部迷走神经干低频刺激对SD大鼠房颤模型的抑制作用及心房肌凋亡率和同型半胱氨酸(Hcy)、间隙连接蛋白43(Cx43)水平的影响。方法选择80只实验SD大鼠作为研究对象,使用随机数字分为4组:空白对照组(A组)、模型组(B组)、假手术组(C组)、治疗组(D组),每组20只。4组大鼠均治疗2周,分别对组大鼠心房有效不应期(ERP)以及房颤诱发情况、心肌组织Hcy、Cx43水平、心肌凋亡率之间的差异以及大鼠心房肌凋亡比率与心肌组织Hcy、Cx43水平相关性进行分析。结果 4组大鼠的ERP从高到低依次为A、C、B、D组,A、C两组大鼠均未出现房颤,且D组大鼠的房颤频率以及持续时间均显著小于B组大鼠;B、C两组大鼠的Hcy、Cx43水平差异无统计学意义(P0.05),而其他两两比较之间的差异有统计学意义(P0.05);B、C两组大鼠的心房肌心肌凋亡率之间的差异无统计学意义,而其他两两比较之间的差异有统计学意义(P0.05);大鼠的心房肌凋亡比率与心肌组织Hcy、Cx43水平呈现正相关。结论通过对模拟房颤实验大鼠进行颈迷走神经的刺激作用,实验大鼠的Hcy、Cx43水平显著降低,患者的心肌凋亡率显著下降,房颤频率以及持续时间显著缩短。     

山羊冠状静脉窦和Marshall静脉的组织学及亚微结构

目的探讨山羊心脏冠状窦和Marshall静脉肌桥及其血管壁的组织学构造和亚微结构特点,为研究局灶性心房纤颤奠定形态学基础。方法取快成年山羊冠状静脉窦和Marshall静脉,利用石蜡切片,HE和Marsson染色法,光镜观察血管壁的组织构筑。利用透射电镜技术观察两种血管壁的亚微结构。结果山羊冠状静脉窦Marshall静脉表面存在一层厚薄不均的心肌纤维———肌桥,肌桥和两种血管壁中膜的细胞呈细胞圆柱形,不分叉,有横纹;细胞质具有松散的肌原纤维丝,线粒体丰富。细胞核椭圆形,位于细胞中央。闰盘简单,多以直线型为主,桥粒、缝隙连接较多。肌桥和血管壁存在丰富的神经末梢和神经节。结论山羊冠状窦和Marshall静脉表面覆盖有心肌纤维,是左右心房的异常通道之一。Marshall静脉和冠状静脉窦中膜由心肌细胞组成,这些细胞具备Pukinje细胞的特点,这可能是引起局灶性心房颤的解剖学基础。     

乳鼠心肌细胞可成片生长的分离和培养方法北大核心

背景:传统方法培养的心肌细胞活力、纯度仍不高,细胞多呈簇状生长,细胞与细胞之间的联系较少,细胞多呈单个搏动。目的:改进传统的乳鼠心肌细胞培养方法,获得纯度高、成片生长的心肌细胞。方法:运用0.1%胰蛋白酶4℃过夜消化心肌组织后加入Ⅱ型胶原酶重复消化,二次差速贴壁分离法联合化学抑制剂纯化心肌细胞。倒置相差显微镜下动态观察心肌细胞形态变化,培养48 h后用抗心肌肌钙蛋白T抗体鉴定心肌细胞纯度,连续10 d隔日记录心肌细胞的搏动频率。结果与结论:(1)心肌细胞在24 h内贴壁,72 h后成簇状分布,5-7 d细胞连接成片生长;(2)细胞存活率为96%,免疫荧光鉴定心肌细胞纯度97%以上,连续10 d内心肌细胞搏动频率差异无显著性意义(P>0.05);(3)综上,通过这种改进的培养方式获得成片生长的心肌细胞纯度、活力更高,是一种更为有效的乳鼠心肌细胞培养方法。     

快速心房起搏兔肺静脉心肌袖细胞膜钾通道基因表达及胺碘酮的影响

目的： 观察快速心房起搏对兔肺静脉心肌袖细胞膜钾通道及其亚型(Kv4.3、Kir6.2)基因表达的影响及胺碘酮的干预作用。方法： 新西兰兔30只，随机分为3组(n=10)，Ⅰ组：对照组；Ⅱ组：快速心房起搏组；Ⅲ组：心房快速起搏+胺碘酮组。3组均经颈内静脉将电极置入右心房，其中Ⅰ组不予心房起搏，Ⅱ组和Ⅲ组以600 beats/min连续起搏右心房7 d；同时Ⅲ组按100 mg·kg^-1·d^-1给予胺碘酮灌胃，Ⅰ组和Ⅱ组则给予等量无药物成分的糖片(安慰剂)7 d。剪取3组兔的肺静脉心肌袖组织，应用逆转录-聚合酶链反应技术(RT-PCR)以3-磷酸甘油醛脱氢酶(GAPDH)为内参照，测定肺静脉心肌袖细胞Kv4.3、Kir6.2的mRNA表达水平。结果： Ⅱ组Kv4.3钾通道mRNA表达低于Ⅰ组45%(P<0.01)，Ⅲ组低于Ⅰ组73％（P<0.01),Ⅲ组低于Ⅱ组51%(P<0.01),Kir6.2mRNA的表达Ⅱ组比Ⅰ组高32%(P<0.01)，Ⅲ组与Ⅰ组无明显差异（P>0.05)，Ⅲ组低于Ⅱ组22%(P<0.05)。结论： 快速心房起搏可引起兔肺静脉心肌袖细胞钾通道基因表达变化，后者可能是肺静脉心肌袖接受电刺激后钾离子通道重构的分子基础，肺静脉心肌袖钾通道可能是胺碘酮的作用靶点之一。     

新生儿心肌连接蛋白43、45的表达

目的　研究新生儿心肌不同部位连接蛋白 4 3、4 5 (Cx4 3、Cx4 5 )表达的差异。方法　应用SP免疫组化方法 ,分析和比较 6例新生儿心不同腔室心肌细胞Cx4 3、Cx4 5的表达。结果　 1 新生儿心肌Cx4 3的蛋白表达在心四个腔均有表达 ,呈斑点状遍布于整个心房肌和心室肌的细胞质内和细胞膜表面 ,少数位于闰盘处 ;Cx4 3、主要在心室肌表达 ,心房较少 ;2 Cx4 3与Cx4 5的分布类似 ,但远少于Cx4 3。结论　Cx4 3主要分布于新生儿心肌细胞质内和细胞表面。心室表达多于心房 ,Cx4 5和Cx4 3分布相似 ,但不如Cx4 3丰富。     

山羊肺静脉心肌袖解剖学观测

目的观察山羊肺静脉心肌袖的形态特征,为异位房颤动物模型提供形态资料。方法解剖30例山羊肺静脉,充分暴露心肌袖,进行形态学观测。结果30例羊心均出现肺静脉心肌袖,其中斜形47.6%,环形40.9%,纵形11.5%。右上、右下、左下、左上肌袖厚度分别为0.46±0.14mm、0.35±0.16mm、0.35±0.11mm、0.37±0.13mm,长度分别为10.75±3.15mm、9.46±2.20mm、11.41±2.87mm、9.20±2.88mm。结论30例山羊肺静脉心肌袖出现率为100%,可能与局灶性房颤的发生有关。     

Role of Relative Changes in Caval Flows for Evaluation of Right Atrial Pressure Shifts Induced by Nitroglycerin

Experiments on cats treated with nitroglycerin showed dynamic relationship between changes in caval venous flows: blood flow increased in the superior vena cava and decreased in the inferior vena cava. Blood pressure in the right atrium either decreased, or increased. No significant changes in total venous return were observed during maximum shifts in right atrial pressure, while contractility of the right ventricular myocardium usually decreased. Our findings suggest that the direction of the right atrial pressure shifts induced by nitroglycerin does not depend on venous return, but is determined by the prevalence of flow changes in the superior vena cava or inferior vena cava.     

Dynamics of Nitroglycerin-Induced Changes in Vena Cava Flows and Right Atrial Pressure

In anesthetized cats, nitroglycerin increased blood flow in the superior vena cava and decreased the flow in the inferior vena cava and total venous return. Simultaneous changes in right atrial pressure could be either positive or negative. The shifts in the superior vena cava flow and right atrial pressure preceded the corresponding alterations in the inferior vena cava flow and venous return.     

Chiari anomalies in the human right atrium

Chiari anomalies in the human right atrium ostensibly are encountered rarely. There is only sporadic mention in the literature of these fenestrated, net-like valves of the inferior vena cava, coronary sinus, or various strands connecting these with other right atrial structures. The effects of such structural anomalies on heart function are unknown. We report here gross observations of the right atrial net from among 213 cadavers, 38 autopsied, and 11 fetal hearts. Histological and ultrastructural examination of inferior vena cava and coronary sinus valves demonstrated that only the anomalous coronary sinus valves contained cardiac muscle. Chiari anomalies typically have referred to perforations or tissue strands related to the inferior vena cava valve and possibly the coronary sinus valve. The anomaly commonly is cited as occurring in 2% of individuals, although there has been no study to support this. We observed Chiari malformations in 13.6% of the 213 cadaver hearts, and 10.5% of the autopsied hearts examined. Of these malformations, the coronary sinus valve was fenestrated most frequently. We propose the term "right atrial net" for "Chiari net," for anomalies involving valves of the inferior vena cava and coronary sinus, and strands within the right atrium connecting these valves with the crista terminalis, right atrial wall, or interatrial septum.     

Double superior vena cava and anomaly of cardiovascular system with a review of the literature

In a student course of gross anatomy dissection at Kanagawa Dental College in 2008, we found an extremely rare case of the double superior vena cava that has a shunt between the right and left atria of a 81-year-old Japanese male cadaver. The left superior vena cava passed through the space between the left cardiac auricle and the left pulmonary vein and entered the coronary sulcus. Then it opened near the opening of the inferior vena cava as the coronary venous sinus to the right atrium. The upper edge of the interatrial septum was located at the site where the right superior vena cava opened to the right atrium. Accordingly, the right atrium connected with left atrium through this site. We discuss the anatomy and etiology of these anomalous structures with a brief review of the literature.     

Effect of stimulating right atrial receptors on urine flow in the dog

1. Complex unencapsulated nerve endings (right atrial receptors) have previously been found in the endocardium of the right atrial appendage and the junction between the superior vena cava and the right atrium.2. Distension of balloons located in the right atrial appendage and at the junction between the superior vena cava and the right atrium resulted in an increase in urine flow. This diuresis was accompanied by a small increase in the excretion of sodium.3. Cooling the right cervical vagus caused a reduction in the response to distension of the right atrial appendage.4. It is concluded that stimulation of right atrial receptors by the distension of balloons located in the right atrial appendage and at the junction between the right atrium and the superior vena cava results in a reflex increase in urine flow.     

Simultaneous occurrence of a thyromediastinal muscle,a truncus bicaroticobrachialis,and a left superior vena cava

A case is presented of a combination of anatomical anomalies found in a 67-year-old female cadaver during routine dissection by medical students. They include a thyromediastinal muscle, a truncus bicaroticobrachialis, and a left superior vena cava, with complete absence of the right superior vena cava, but with a normal azygos vein opening into the right atrium at the expected site of entry of the superior vena cava. No associated congenital cardiac malformations were found. Clinical implications include the difficulty of heart catheterization through the subclavian veins and misleading images on CT or MRI scans, where the azygos vein could be mistaken for a right superior vena cava.     

The effect of stretching the superior vena caval—right atrial junction on right atrial receptors in the dog

1. Action potentials were recorded from fibres in the right cervical vagus, the receptor endings of which were localized to the endocardial surface of the superior vena caval-right atrial junction.2. Stretching the junction between the superior vena cava and the right atrium without obstructing venous return caused an increase in the discharge of these fibres. This increase in impulse frequency was similar to that caused by small changes in mean right atrial pressure (range 0-13.5 cm H(2)O).3. This evidence supports the earlier suggestion that stimulation of the right atrial receptors by stretching the superior vena caval-right atrial junction causes a reflex increase in heart rate.     

A reflex increase in heart rate from distension of the junction between the superior vena cava and the right atrium

1. Localized distension of the junction between the superior vena cava and the right atrium without obstructing venous return caused an increase in heart rate.2. This increase in heart rate was a reflex response; the afferent path was in the vagi and the efferent solely in the sympathetic nerves.3. The receptors most likely to be stimulated by the distension of the junction between the superior vena cava and the right atrium are the right atrial receptors located on the endocardial surface of the intrapericardial portion of the superior vena caval-right atrial junction.     

Relationships between Venous Return and Blood Pressure in Caval Veins and Right Atrium During Pressor Stimulation

The dynamics of changes in blood flow and pressure in the superior and inferior vena cava, total venous return, and right atrial pressure in response to pressor stimuli were studied in acute experiments on cats. It was shown that blood flow and pressure in caval veins changed synchronously and unidirectionally, while shifts in the right atrial pressure did not depend on direction and magnitude of changes in caval flow and pressure and total venous return. Our results suggest that right atrial pressure does not play a role in the regulation of venous return.     

经左颈静脉插管肝内门-体静脉分流术的应用解剖

为给临床经左颈静脉插管行肝内门 -体静脉支架分流术提供解剖学依据 ,在 4 8例成人尸体上解剖并观测了双侧颈内静脉、头臂静脉、上腔静脉、右心房、下腔静脉上段的长度、外径、以及各有关静脉间的角度。结果为左颈内静脉长度 :10 6.9± 18.3 m m,外径 :13 .6± 3 .4 mm ;左头臂静脉长度 :66.3± 10 .8mm ,外径 :15 .9± 4 .1mm;上腔静脉长度 :4 8.5± 9.8mm,外径 :2 1.4± 8.4 mm;右心房长度 :68.7± 17.4 m m,上口外径 :2 0 .2± 4 .7mm,下口外径 :2 3 .9± 6.0 m m;下腔静脉上段长度 :2 1.5± 6.5 m m;左颈内静脉延长线与左头臂静脉间的角度 :4 5 .5°± 10 .3°,左头臂静脉延长线与上腔静脉间的角度 :5 8.3°± 12 .7°;5 8.3°± 12 .7°;左颈内静穿刺点至肝静脉口的总长 :2 4 3 .2± 2 3 .6m m。结论 :在经左颈内静脉行肝内门 -体静脉分流术时只要掌握了插管静脉的角度和深度仍具备和右侧穿刺途径一样多的优点