婴幼儿和法洛氏四联症房室结和房室束的外科解剖及计算机三维重建Ⅰ.位置与毗邻

通过对15例人心(成人5例,婴幼儿5例,法四5例)房室结和房室束的连续切片观察和图像分析,表明:15例房室结均位于Koch三角内.与成人相比,婴幼儿房室结位置相对较高,法四房室结位置偏低,其结前部紧靠三尖瓣隔瓣根部.婴幼儿房室束多位子三尖瓣隔瓣附着缘以上的房室肌隔内或室嵴顶部,而法四房室束起始部紧邻三尖瓣隔瓣根部的深面,其余部份可位:室嵴左侧,室缺的后下缘;房室束可直接位于室缺游离缘的心内膜下,或距室缺游离缘(可为肌性或腱性)1.88-2.14mm处.为临床小儿心外科手术提供了直接的形态学依据.     

胎儿房室结的组织学和组织化学研究

利用光镜观察了２０例胎儿室房结、房室束和左、右束支的组织结构和组织化学特征。结果如下：１、胎儿房室结位于三尖瓣隔侧瓣上方，中心纤维体右侧。结石侧有普通心肌组成的覆盖层。房室结可分深浅两部。浅部纤维平行排列，垂直下行，止于结的下端。深部可分为上和下部。深部向后延伸与房间隔肌相连，向前延续为房室束。深部向右深入中心纤维体内形成许多细胞岛。２、房室束横断面大多为三角形，外包有疏松结缔组织鞘。房室束的前部     

KOCH三角的解剖

本实验解剖了110例人心标本(成人70、儿童40)的Koch三角区,观察和测量了房室结的形态、大小、毗邻和标志。房间隔及冠状窦口上、下方均有肌束连于房室结。Todaro腱在儿童多全部为腱性;在成人,其后部为肌性。三角区的深面为左、右心房壁和室间隔顶所构成的锥形间隙,其内为进入房室结区的血管和神经。根据构成不同,可将三角区分为5个区,即前上角的纤维支架区和房室结区,其余部分自上向下分别为房间隔区、右房壁区和室间隔区。本文还讨论了这些形态结构的功能及外科意义。     

人体心脏房室结、房室环及主动脉后结的巨微解剖

目的解剖分离人体心脏房室结和房室环的结构,阐述它们的形态特征及相互关系。方法通过体视显微镜解剖12例人体心脏的房室结、主动脉后结及房室环,再进行组织学观察,并绘图演示它们的结构关系。结果在二尖瓣环和三尖瓣环靠近冠状窦前缘处分别暴露了左、右房室环(12/12),直径分别为(0.69±0.12)mm、(0.78±0.13)mm。此处的左、右房室环穿行在房室隔内的心房肌与心室肌之间的间隙中,向房室结方向延伸。主动脉后结在主动脉根后方的房间隔中被探查到(7/9),它的后上方的房间隔间隙中有肌纤维与其相连,它的前下方分出左、右房室环,并且此处的左环比右环粗。在中心纤维体后方的心内膜下的深部,主动脉后结与房室结之间有直接的心肌组织连接通路,这条通路有别于另两条通路(左、右房室环)。结论主动脉后结和房室环可通过体视显微镜解剖暴露,主动脉后结与房室结之间有3条通路。     

房室交界区三角的观察和测量

在110例人心(成人70,儿童40)上,观察了由冠状窦口、Todaro腱及三尖瓣隔瓣附着缘围成的房室交界区三角,对上述各边界及室间隔膜部进行了测量。三角的三个角各有不同结构占据,前上角为房室结,顶角有冠状窦和心最小静脉开口,后下角深面为右冠状动脉“U”形袢。就上述特点结合临床进行了讨论。     

成人房室隔的研究

利用56例成人心脏标本和4例心脏切片对人心房室隔进行了观察和测量.认为房室隔位于右房与左室之间,上界为二尖瓣前瓣环和主动脉后瓣环与右瓣环,下界为三尖瓣隔侧瓣附着缘.前界为室上嵴后缘,后界为冠状窦口.房室隔分为前部与后部,分别与左室流出道和流入道相对应.测量了房室隔的下缘下、前部长和后部长,分别为2.95±0.08,1.62±0.07和1.33±0.07cm;测量后缘宽、中部宽和前部宽,分别为1.61±0.05,1.04±0.04和0.49±0.04cm.描述了各部的组织结构.对房室隔的命名、机能和临床意义进行了讨论.     

房室结后延伸部形态学特征及与折返性心动过速的关系

目的：研究人房室结双径路，尤其是慢径的解剖学基础。方法：(1)取17例尸检心脏包括房室结在内的房室交界区的组织固定、脱水、包埋后切片，HE和Masson染色，光镜规察(2)由冠状窦151向房室结方向在心内膜下注射墨汁0．5ml，24h后光镜观察墨汁走向?结果：17例标本均可发现房室结，房室结前向形成房室束(His束)，发现47％(8例)有明确向后延伸一左后延伸和彳丁后延伸，35％(6例)仅有右后延伸，1例发现仅有左后延伸，2例未发现有向后延伸。向后延伸南房室结自然延伸而成，其有房室结自然延伸而成，左后延伸朝左行向房间隔，有后延伸行向有，与三尖瓣隔瓣近乎平行，纤维可达冠状窦口附近。结论：房室结后延伸部可能为慢径路，作为房室结折返性心动过速(AVNRT)的射频消融慢径的解剖学基础、     

人心传导系统的变异

目的　探讨划分心传导系统 (CCS)形态变异与发育异常 (畸形 )的界线。　方法　用我们建立的CCS检查法 ,即窦房结和房室结沿其长轴切 1～ 2块 ,房室束沿长轴垂直切 2～ 4块 ,连续切片 ,间断取片 ,每例共取 30片。对 886例 (非心源性死亡 737例 ,心源性猝死 149例 )人CCS进行组织学观察 ,并对两组进行CCS形态、死因分析比较。　结果　 1 人CCS具有大小、位置及形态的先天性变异 ;2 也有增龄性变化的后天性变异 ;3 死因不明的心源性猝死者中CCS见到有成年人胎儿型房室结、房室结全部移位至房室束穿部、房室束穿部完全分成 3束以上、房室束分叉部房室结化及移位至三尖瓣根部等 ,这些改变不应认为是正常变异 ,因为它们都可能有病理学意义。　结论　房室束分叉部向室间隔膜部内移位、偏位于室间隔左侧、向室间隔左下侧移位 ,以及不足 1 2房室结移位至中心纤维体内 (房室束穿部 ) ,心肌束移位于房室束或左束支内等应属CCS变异 ,不是畸形。     

广西猕猴房室结的形态学特征

目的探讨猴房室结的形态学特征,比较物种之间的生物学差异。方法取4例广西猕猴房室结区域,石蜡包埋,连续切片,分别用HE染色、Van Gieson染色和间苯二酚品红液染色,光镜观察其房室结的形态学特征和组织结构。结果猴房室结呈前后长的三角体状。左侧紧贴中心纤维体,右侧有胶原纤维和心房肌覆盖。向前延续为房室束。房室结内存在少量起搏细胞、Purkinje细胞和大量移行细胞。细胞间质内含量有大量胶原纤维和丰富的弹性纤维,两者交织成网。结论广西猕猴房室结的形态较人和其他动物相似,细胞成分较成年人典型,间质内胶原纤维和大量弹力纤维丰富。     

婴幼儿和法洛氏四联症房室结和房室束的外科解剖及计算机三维重建Ⅱ.光镜形态与计算机三维重建

15例人心房室结和房室束的连续切片观察表明:多数成人房室结细胞排列较致密,结内结缔组织较多,有明显的脂肪浸润;另一例房室结仅由纵行细胞组成的松散样结构.婴幼儿房室结细胞有的排列松散,有的排列致密,易形成细胞岛和Mahaim束,结内结缔组织较少,未见脂肪浸润,法四房室结细胞排列致密.同时,在VAX-11/730主机和S-600图象处理系统下,用Fortran-77编制的软件包,对一例正常婴幼儿的房室结和房室束进行了三维重建,在彩色监视器的屏幕上显示了不同角度的房室结和房室束及其毗邻结构,并用透明法处理显示了它们之间的位置关系.     

成人房室交界区过渡细胞束形态学及连接蛋白43和40的表达

目的 观察临床上心律失常常见发生部位及射频消融治疗靶点部位--房室交界区和邻近区域的形态学特点及连接蛋白(Cx)43和40的表达,为心律失常发生机制及可能的有效治疗部位提供形态学依据.方法 10例正常成人心脏,选取房室交界区及其邻近部位,常规石蜡包埋,HE、Masson染色,选定目标部位行Cx43、Cx40免疫组织化学...     

Observation of root variations in human coronary arteries

In dissection courses conducted from 1999 through to 2003, five specimens were found to have coronary arteries with variant roots and branches, as follows: in specimens 1-4, roots of the right coronary artery (RCA) and right conus branch arose independently from the right aortic sinus (RAS); in specimen 5, the RCA and left coronary artery (LCA) originated from the RAS. The LCA pierced the upper part of the muscular interventricular septum and appeared on the surface, then dividing into the anterior interventricular and the circumflex branches. In the present study, we considered that the right conus arteries in specimens 1-4 were the remnant blood capillaries around the aorta towards the RAS in the embryonic stage. In specimen 5, the vessel near the left aortic sinus was poorly developed as a small thin artery. Instead, the LCA was developed from the anterior and posterior interventricular septal branches.     

Atrioventricular node and input pathways: a correlated gross anatomical and histological study of the canine atrioventricular junctional region

To determine the architecture of the atrioventricular (AV) junctional region, structures in atrial preparations were correlated to those in serial sections made either parallel or perpendicular to the long axis of the AV node (AVN)/AV bundle complex. The results demonstrated the following for the first time: 1) A right medial atrial wall (MAW) extends anteriorly from the interatrial septum, superior to the interventricular septum (IVS). 2) An atrial interventricular septum (A-IVS) groove is located between the base of the MAW and the crest of the IVS. 3) Three atrionodal bundles converge to form a proximal AV bundle (PAVB), which in turn is contiguous with the AVN. The atrionodal bundles are associated with the MAW or the superomedial and inferolateral margins of the coronory sinus. Terminal portions of the atrionodal bundles and the PAVB reside within the A-IVS groove. The AV bundle was termed distal (DAVB) to avoid confusion. 4) The location of the AVN/DAVB complex topographically is deep to the apex of the septal cusp of the tricuspid valve subjacent to the MAW. Intracardially, the AVN/DAVB complex is within the central fibrous body. Significantly, this study resulted in the first unequivocal demonstration of discrete bundles of myocardial fibers associated with the atrial end of the AV node. Moreover, it appears likely that the atrionodal AV bundles are continuous with the sinoatrial nodal extensions, thereby forming internodal tracts.     

Anatomic bases of the surgical division of Kent bundles in the posterior septal area of the heart

The first part of this paper deals with the general anatomy of the postero-septal area of the heart, with particular emphasis on the relationships between the mitral and tricuspid anuli and the right fibrous trigone, between the conducting system and the interatrial septum, and between the right atrium and the posterior superior process of the left ventricle. In the second part, we describe the operative procedure that has been developed for dividing right and left posteroseptal Kent bundles. The key to this technique is the opening of the right atrium along the tricuspid anulus down to the orifice of the coronary ostium; this offers an excellent exposure on the posterior aspect of the septal area, and allows dissection of the sulcus fat pad from the muscular portion of the interventricular septum and the adjacent posterior superior process of the left ventricle down to the level of the mitral anulus. This planned dissection increases the likelihood of interrupting the anomalous pathways without injury to the normal conducting system which remains encompassed within the interatrial septum and the right fibrous trigone.     

Cardiac conduction system in the chicken: Gross anatomy plus light and electron microscopy

Twenty-three chicken hearts were used to study the cardiac conduction system by light and electron microscopy. In addition to a sinus node, atrioventricular node (AVN), His bundle, left and right bundle branches (LBB, RBB), the chicken also has an AV Purkinje ring and a special middle bundle branch (MBB). The sinus node lies near the base of the lower portion of the right sinoatrial valve. The AV node is just above the tricuspid valve and anterior to the coronary sinus. The His bundle descends from the anterior and inferior margin of the AV node into the interventricular septum, then dividing into right, left and middle branches some distance below the septal crest. The middle bundle branch turns posteriorly toward the root of the aorta. The AV Purkinje ring originates from the proximal AV node and then encircles the right AV orifice, joining the MBB to form a figure-of-eight loop. The chicken conduction system contains four types of myocytes: (1) The P cell is small and rounded, with a relatively large nucleus and sparse myofibrils. (2) The transitional cell is slender and full of myofibrils. (3) The Purkinje-like cell resembles the typical Purkinje cell, but is smaller and darker. (4) The Purkinje cell is found in the His bundle, its branches, and the periarterial and subendocardial Purkinje network. © 1993 Wiley-Liss, Inc.     

Role of the left interventricular sulcus in formation of interventricular septum and crista supraventricularis in normal human cardiogenesis.

Serial sections of normal human embryos were studied and three-dimensional images reconstructed to determine the early development of the interventricular septum. The position of the interventricular septum is determined in stage 9 of normal development by the formation of the left interventricular sulcus. As a result of unknown properties of the cells of the myocardial layer, the left interventricular sulcus persists while the right disappears, producing the initial lateral asymmetry of the primary heart tube. By stage 14, the left interventricular sulcus forms a spiral which is continuous with the developing interventricular septum. The dorsal limb of the spiral passes to the right between the atrioventricular canal and the origin of the outflow tract, and is lost in the wall of the trabeculated right ventricle. It appears that this dorsal limb of the spiral is the precursor of part of the cirsta supraventricularis. The midportion of the sulcus, the bulboventricular groove, becomes the so-called fibrous continuity between the aortic and mitral valves. The ventral limb of the spiral passes caudally in the anterior interventricular groove and then dorsally and cranially toward the dorsal cushion of the atrioventricular canal. The ventral limb of the spiral is continuous with the crest of the muscular interventricular septum, which develops by apposition of tissue from the expanding right and left ventricles. From stage 14 to stage 19, the muscular interventricular septum, the atrioventricular endocardial cushions, and the ventricular end of the spiral ridges of the outflow tract appose and fuse. Subsequent formation of the membranous interventricular septum completes the physical separation of the right and left ventricles.     

Role of the left interventricular sulcus in formation of the interventricular septum and crista supraventricularis in normal human cardiogenesis

Serial sections of normal human embryos were studied and three-dimensional images reconstructed to determine the early development of the interventricular septum. The position of the interventricular septum is determined in stage 9 of normal development by the formation of the left interventricular sulcus. As a result of unknown properties of the cells of the myocardial layer, the left interventricular sulcus persists while the right disappears, producing the initial lateral asymmetry of the primary heart tube. By stage 14, the left interventricular sulcus forms a spiral which is continuous with the developing interventricular septum. The dorsal limb of the spiral passes to the right between the atrioventricular canal and the origin of the outflow tract, and is lost in the wall of the trabeculated right ventricle. It appears that this dorsal limb of the spiral is the precursor of part of the cirsta supraventricularis. The midportion of the sulcus, the bulboventricular groove, becomes the socalled fibrous continuity between the aortic and mitral valves. The ventral limb of the spiral passes caudally in the anterior interventricular groove and then dorsally and cranially toward the dorsal cushion of the atrioventricular canal. The ventral limb of the spiral is continuous with the crest of the muscular interventricular septum, which develops by apposition of tissue from the expanding right and left ventricles. From stage 14 to stage 19, the muscular interventricular septum, the atrioventricular endocardial cushions, and the ventricular end of the spiral ridges of the outflow tract appose and fuse. Subsequent formation of the membranous interventricular septum completes the physical separation of the right and left ventricles.