新生儿心脏的解剖学观测

1 材料和方法选取长春地区、经防腐固定的50例足月新生儿,男30女20.开胸,至心包处断离各血管.(主动脉、肺动脉自瓣膜平面切除)取心,用游标卡尺、铅丝、双角规测心外径.沿血流方向剖开心脏,流水下冲洗内部杂质,称重.在大口径量杯内(排水法)量全心实质体积.以室间隔中点前室间沟两侧为准,测左右室壁厚度.乳头肌按群取最大、最小值,并计出均值.腱索起、止端分别计数,长度从乳头肌尖端至瓣膜附着处的直线距离计算.所有数据,均经统计学处理(X±S,最小值.最大值).2 结果2.1 心脏重量,体积和室壁厚度,结果如下表1.     

成人右房室瓣乳头肌腱索支配的解剖类型调查

目前，国内外学者对成人心脏右房室瓣主瓣、副瓣支配其运动的乳头肌和腱索的数目多少见解不一，由于近十多年来心脏外科的迅速发展，为了进一步提供国人右房室瓣所支配的乳头肌及腱索的资料，以供临床参考，本文对国人心脏右房室瓣乳头肌腱索支配的解剖类型进行了调查。     

左室假腱索的解剖学研究及其临床意义

目的　为临床提供有关左室假腱索的解剖学基础。方法　采用 44例成人心脏标本 ,观察左室假腱索的出现率、附着点和形态 ,并对其长度和直径进行测量。结果　 44例心脏中 33例 (75 % )出现左室假腱索共 75条 ,平均每例 2 .2 7± 1 .38条。左室假腱索多附着于室间隔和后乳头肌、乳头肌和游离室壁之间。左室假腱索的长度和直径分别为 1 4 .62± 7.2 9mm和 0 .69± 0 .64mm。结论　左室假腱索是心内正常解剖结构 ,了解其形态特征 ,有助于临床的诊断     

缺氧性肺动脉高压大鼠右心室重构

摘要目的：研究缺氧性肺动脉高压大鼠右心室重构情况。方法：常压间断缺氧法复制缺氧性肺动脉高压大鼠模型，采用右心导管法测定平均肺动脉压力，通过测量右心室流入及流出道长度、左心室壁和右心室壁厚度、右心室和左心室 室间隔重量对其右心室重构情况进行定性研究。结果：缺氧14d后大鼠平均肺动脉压力显著升高，右心室流出道长度及右心室肥大指数显著增加，缺氧21d后右心室游离壁重量显著增加；右心室流人道长度及左、右心室壁厚度与对照组无统计学差异。结论：缺氧性肺动脉高压大鼠右心室早期表现为离心性肥大。     

足月新生儿正常心脏和大血管的形态定量研究

对１００例足月新生儿正常心脏的心房，室壁厚度，上，下腔静脉入口周径和冠状窦口的最大径，卵园的长，短径，左右心室流入，流出道的长度，房室瓣环和动脉瓣环的周径以及大动脉各段的长度和周径等进行了认真的测量和研究。     

左心室乳头肌的超声应用解剖

目的：为临床超声检测左室乳头肌提供应用解剖学资料。方法：在经福尔马林固定的４８例国人心脏标本上，用卡尺、角度尺等在对应左室乳头肌长轴切面下进行了长度与室壁构筑角度的测量。结果：前乳头肌单主支近腔侧长度３０．６±１．３ｍｍ、附壁部长度２６．８±０．９ｍｍ、游离段长度１１．６±１．２ｍｍ，副支近腔侧长度２１．７±０．８ｍｍ、附壁部长度２０．６±０．９ｍｍ、游离段长度１９．８±１．１ｍｍ；后乳头肌单主支近腔侧长度２８．６±２．４ｍｍ、附壁部长度１８．２±２．１ｍｍ、游离段长度９．２±１．３ｍｍ，副支近腔侧长度２２．３±０．９ｍｍ、附壁部长度２１．８±１．１ｍｍ、游离段长度２０．４±０．９ｍｍ。它们与左室壁的构筑角度，以前乳头肌主支（１４．３±１．７°）比后乳头肌（１１．６±１．９°）较大。结论：结果对于左心室乳头肌超声断层长轴切面下检测和临床诊断有明确的指导意义     

胎儿心脏超声检查的临床应用及评价

目的评价胎儿心脏超声对先天性心脏病检查的临床应用及价值意义。方法选取于2010年6月—2013年6月来我院行产前检查的孕妇628例,以胎儿四腔心、左室流出道、右室流出道、三血管、主动脉弓、动脉导管弓切面为标准切面进行筛查,出生后一周进行新生儿彩色多普勒超声心动图检查,其结果与胎儿心脏超声筛查结果对照。结果胎儿心脏超声筛查确诊5例,单心室2例,法乐四联症1例,室间隔缺损2例。结论胎儿心脏超声可以提高先天性心脏病的检出率,对于降低胎儿出生缺陷起着不可替代的作用,也是胎儿产前筛查的重要检查方法。     

中位心及主动脉弓分支变异报道一例

在局部解剖学课程解剖操作过程中,发现1例女性标本心脏及主动脉弓分支血管变异,为积累解剖学资料以及为临床治疗提供参考,现报道如下. 1中位心变异 中位心是指心脏的轮廓处于胸腔中心的位置,心尖指向居中或向右移位.中位心非常少见,文献报道其在新生儿中发病率为0.2/10 000,发生先天性心脏病的概率为0.2％[1].本例标本中心脏整体向右移位,心尖部位与正常位置向右偏离3.45 mm,呈中位心.心脏外观明显偏大,最大横径为117.10 mm,左缘、有缘和下缘长度分别为:105.54 mm、88.34 mm和94.44 mm;左、右心室腔扩张肌层变薄,心室腔最大横径分别为:46.54 mm和30.89 mm,左、右心室壁和室间隔厚度分别为:12.63 mm、7.73 mm和11.44 mm;由于心脏整体向右侧胸腔偏移,对右侧肺脏造成挤压,右肺成狭条状,经肺门处横径为40.96 mm,而左侧肺部饱满,经肺门处横径为60.02 mm,左、右两肺尺寸横向相差近20 mm.     

成人右房室瓣瓣叶分区与形态的解剖观测

目的为心脏右房室瓣病变的临床诊治提供解剖学资料。方法对171个成人心脏右房室瓣瓣叶分区进行形态学测量。结果右房室瓣瓣叶分为粗糙区、透明区、基底区。瓣膜形状有三角形、半椭圆形、半圆形、长方形和梯形。双前瓣瓣叶高度最高,内瓣瓣叶高度最低。前瓣透明区和基底区室面腱索最少,因而前瓣活动性最大。内瓣和后内瓣室面附着的腱索多而短小,使瓣叶活动性最小。结论心脏外科手术中应密切注意瓣叶的解剖学特点。     

右心轴位X线心血管造影解剖

本文按照右心常规位和轴位(长轴位、右前斜延长位和四腔心位)造影的投照方位,对55例右心铸型和心脏断面标本进行了心脏形态和轴位造影的对照研究。结合临床应用,从解剖学角度详细描述了与右心造影有关的正常心脏的形态结构,如房室口、三尖瓣、右室流出道、肺动脉瓣及肺动脉主干、房间隔和室间隔等在造影中的形态位置和联系。并对室上嵴,隔缘肉柱和节制带等肌束的形态结构也进行了讨论。联系标本对右心常规位和轴位造影进行了对比,显示了轴位心血管X线造影在显示心脏内部解剖结构和先心病诊断的应用中的优越性。     

Ischemic myocardial necrosis and papillary muscle dysfunction in infants and children

Ischemic myocardial and papillary muscle dysfunction has considerable implication in newborn infants and children with normal or malformed hearts. Papillary muscle dysfunction in adults primarily involves coronary artery occlusion and ischemic necrosis in the left ventricle and papillary muscles. Infants and children rarely develop coronary artery occlusion. Their myocardial dysfunction and injury occurs with nearly equal frequency in both ventricles as a result of underperfusion from a wide range of causes, including severe birth asphyxia, congenital heart disease, and complications of premature delivery. A history of cardiogenic shock, acute congestive heart failure with cyanosis and atrioventricular murmur, or persistent fetal circulation in a newborn without congenital heart disease should alert the pathologist to the possibility of ischemic myocardial necrosis (IMN). Older infants with ventricular hypertrophy, persistent pulmonary hypertension (PPHN), bronchopulmonary dysplasia (BPD), and those with malformed hearts involving severe ventricular hypertension due to outflow obstruction or pulmonary hypertension may have IMN, fibrosis, or dystrophic calcification alone or in combination. Animal models of adult ischemic cardiac injury may not be suitable for study of the newborn.     

Morphogenesis of chordae tendineae. I: Scanning electron microscopy

The formation of the chordae tendineae of the left atrioventricular valve in the chick embryo is described using scanning electron microscopy. These supportive structures for the valve cusps develop between days 6 and 13 of incubation. Elevations which represent the primitive papillary muscles form on the ventricular wall. These elevations bifurcate into thin, weblike folds which are attached to the primitive valve cusps. The folds are the primordia of the chordae tendineae. Linear ridges develop on the web between the cusp and papillary muscle. These ridges alternate with depressions. The depressions become perforate to create the individual chorda from the linear ridges. Multiple perforations form initially but they typically consolidate to create one large aperture between two chordae. Some interchordal connections of tissue do persist throughout the period studied. During the period of perforation, prominent rounded cells are typical of the endocardium between the chordae. These cells are similar at the scanning electron microscope level to those present in the formation of the foramina secunda of the atrial septum. Primary, secondary, and tertiary chordae tendineae appear to develop in the same manner. First order chordae (those attached at the free margin of a cusp) are not found in the chick embryo. The majority of the chordae are second order, which insert into the ventricular surface of the cusp a short distance from the free edge. These chordae typically have a horizontal banding or grooving along their length. Third order chordae which extend from the papillary muscle to the ventricular wall are also present. It is suggested that chordal development is a programmed cellular and hemodynamic event.     

Muscle Fiber Orientation in the Development and Regression of Right Ventricular Hypertrophy in Pigs

The development and regression of right ventricular hypertrophy was investigated in 12 pigs with special reference to changes in ventricular function and myocardial fiber orientation. Nine ventricles were pressure -loaded by banding the pulmonary artery for 28–81 days, and four of them were then released from the load by removing the band. Right ventricular systolic pressure (RVSP), end-diastolic pressure (RVEDP) and end systolic volume index (ESVI) increased significantly during banding and decreased after debanding. End diastolic volume index (EDVI) and stroke volume index (SVI) showed no significant change during banding and after debanding. The weight of the right ventricle relative to both ventricles (RV/TV) and the thickness of muscle fibers were increased significantly in the loaded ventricles, and reduced again to the control level in ventricles released from the load. The intramyocardial distribution of angles ( θ ) of inclination of muscle fibers from the transverse plane of the outflow tract was estimated histometrically. There was a significantly larger proportion of circularly oriented fibers (|θ|≦30) in the pressure loaded ventricles than in the control, whereas these fibers decreased again to the control level after removal of the pressure load. The present findings indicates that 1) the right ventricular hypertrophy induced by pressure loading is characterized not only by an increase in ventricular weight and muscle fiber thickness, but also by a change in intramyocardial fiber orientation, and 2) the hypertrophic right ventricle can regress both functionally and morphologically to a normal state after removal of the pressure load.     

Morphological innervation pattern of the developing rabbit heart

The morphological innervation pattern of developing fetal and neonatal rabbit hearts was delineated histochemically by a cholinesterase/silver procedure and immunohistochemically with the monoclonal antibody HNK1, an antibody which recognizes some cells derived from neuroectoderm. Cholinesterase-containing nerves appeared distally on the outflow tract by gestational day 15 (G15). Isolated cells with cholinesterase-stained fine processes were present near the base of the pulmonary trunk. HNK1 antibody stained the same nerves and ganglia revealed by the cholinesterase reaction and other nerves in the rabbit heart. It was used to confirm that cells with fine neuron-like processes were present before nerve ingrowth. The G14 heart contained many HNK1 staining cells in the right atrium, outflow, and inflow tracts; cells with fine processes were few but increased at G16. By G17, a plexus of interweaving nerves and associated cells began to form at the base of the pulmonary trunk. Fine nerves encircled the base of the aorta, and others crossed the intercaval region dorsally. At G19, nerves (1) extended downward from a rich “bulbar” plexus along the front ventricular surface, (2) grew near the epicardial surface at the base of the heart along the atrial floor and ventricular roof, (3) traversed the vena cavae and intercaval region to enter the atrial roof, and (4) crossed the coronary sinus to reach the back ventricular walls. By G23, cholinesterase-staining nerves and ganglia in the atria and, epicardially, in the ventricles formed the general innervation pattern of the newborn and adult rabbit heart.     

Morpho‐functional characterization of the heart of Gallus gallus domesticus with special reference to the right muscular atrioventricular valve

In this work, we studied the structure and function of the adult chicken heart with a focus on the right muscular atrioventricular valve using anatomic and echocardiographic methods. We demonstrated that the free wall thickness of the right and left ventricles changes from the apex to the base of the heart. The right muscular atrioventricular valve (RAVV) is joined directly to both the parietal right ventricle free wall (one attachment) and the interventricular septum (two attachments: ventral and dorsal). This valve does not have chordae tendineae or papillary muscles. The quantitative morphological and functional characterization of the RAVV is given. In color Doppler echo, no regurgitation of blood flow in the RAVV was observed in any of the studied birds. The blood flow velocity in the RAVV is 56.2 ± 9.6 cm s^‐1. A contractile function of the RAVV is shown. Based on the findings obtained, we conclude that the RAVV has a sufficient barrier function. In addition, as this valve is an integral part of the right ventricle free wall, it contributes to the right ventricle pump function. An agreed nomenclature of the parts of the RAVV is required.     

Myosin light chain 2a and 2v identifies the embryonic outflow tract myocardium in the developing rodent heart

The embryonic heart consists of five segments comprising the fast‐conducting atrial and ventricular segments flanked by slow‐conducting segments, i.e. inflow tract, atrioventricular canal and outflow tract. Although the incorporation of the flanking segments into the definitive atrial and ventricular chambers with development is generally accepted now, the contribution of the outflow tract myocardium to the definitive ventricles remained controversial mainly due to the lack of appropriate markers. For that reason we performed a detailed study of the pattern of expression of myosin light chain (MLC) 2a and 2v by in situ hybridization and immunohistochemistry during rat and mouse heart development. Expression of MLC2a mRNA displays a postero‐anterior gradient in the tubular heart. In the embryonic heart it is down‐regulated in the ventricular compartment and remains high in the outflow tract, atrioventricular canal, atria and inflow tract myocardium. MLC2v is strongly expressed in the ventricular myocardium and distinctly lower in the outflow tract and atrioventricular canal. The co‐expression of MLC2a and MLC2v in the outflow tract and atrioventricular canal, together with the single expression in the atrial (MLC2a) and ventricular (MLC2v) myocardium, permits the delineation of their boundaries. With development, myocardial cells are observed in the lower endocardial ridges that share MLC2a and MLC2v expression with the myocardial cells of the outflow tract. In neonates, MLC2a continues to be expressed around both right and left semilunar valves, the outlet septum and the non‐trabeculated right ventricular outlet. These findings demonstrate the contribution of the outflow tract to the definitive ventricles and demonstrate that the outlet septum is derived from outflow tract myocardium. Anat Rec 254:135–146, 1999. © 1999 Wiley‐Liss, Inc.     

Histopathological and ultrastructural changes in 57 cases of high altitude heart disease]

This paper reports the histopathologic and ultrastructural changes in 37 children and 20 adults with high altitude heart disease. Its clinicopathologic features, diagnostic criteria and differential diagnosis from Ke-shan disease and other heart diseases are discussed. The right heart of 37 children showed hypertrophy and dilatation. Microscopically, necrosis and scarring were found mainly in the right ventricular wall (29/37) and the anterior papillary muscles (29/37) of the right ventricle. The hearts of 20 adults (19 Hans and 1 Tibetan) were enlarged and increased in weight. Heart weight increased to 400-500g in 15 cases, and hypertrophy of both ventricles was seen in 16 cases. Necrosis and scarring were found mainly in the papillary muscles (20:16) and the ventricular walls (11:19) of the left and right ventricles. Electronmicroscopy showed that myofibrils were dissolved or degenerated, mitochondria swelled, endoplasmic reticula dilated and glycogen granules decreased. As regards the pathogenesis, the authors stress the role of chronic hypoxia which causes myocardial damage, and advocate the importance of early diagnosis and treatment.     

Isomyosin expression patterns in tubular stages of chicken heart development: a 3-D immunohistochemical analysis

Summary The 3-D distribution of atrial and ventricular isomyosins is analysed in tubular chicken hearts (stage 12+ to 17 (H/H)) using antibodies specific for adult chicken atrial and ventricular myosin heavy chains, respectively.At stage 12+ (H/H) all myocytes express the atrial isomyosin; furthermore, all myocytes except those originally situated in the dorsolateral wall of the sinu-atrium coexpress the ventricular isomyosin as well. Moreover, it appears that recently incorporated myocardial cells at both ends of the heart tube start with a coexpression of both isomyosins. From stage 14 (H/H) onwards a regional loss of expression of one of either isomyosins is observed in the atrial and ventricular compartment. In this way the single isomyosin expression types that are characteristic for the adult working myocardium of the atria and ventricles arise. So, the isomyosin expression patterns are, unexpectedly, hardly useful to discriminate the different heart parts of the tubular heart. The ventricle, defined by its adult type of isomyosin expression, is even not detectable before stage 14 (H/H). Interestingly, interconnected coexpression areas, which may be precursor conductive tissues, are still present at stage 17 (H/H) in the outflow tract, the ventricular trabeculae, the atrio-ventricular transitional zone and in the sinuatrium.The pattern of isomyosin coexpression was found to correlate with a peristaltoid contraction and a slow conduction velocity, whereas single expression areas correlate with a synchronous contraction and a relatively fast conduction velocity.The possible implications of the changing isomyosin pattern for the differentiation of the tubular myocardium, in particular in relation to the development of the conductive tissues, will be discussed.Abbreviation H/H staged according to the classification of Hamburger and Hamilton (1951)     

Development of the outflow tract and closure of the interventricular septum in the normal human heart

The majority of congenital heart malformations in humans involve defects in the atrioventricular valves, the crest of the interventricular septum, and/or the outflow tract, but the position and timing of these structures during cardiac development is controversial. We examined all 622 staged, serially sectioned normal human embryos and fetuses in the Carnegie Embryological Collection, and obtained a statistical tabulation of the appearance of the endocardial cushion components and surrounding structures for 382 embryos in good condition between stages 9 and 23 inclusive, when the heart normally develops. Accurately scaled drawings of ventral and lateral views of the hearts of seven embryos from stage 13 through 22 were prepared from graphic reconstructions in order to visualize the relationships of the structures under consideration. We found that development of the outflow tract septum follows the apparent functional separation of both the left and right ventricles and the blood streams leaving them. Elevations of the endocardial cushion material are continuous throughout the outflow tract and develop as a consequence of the elliptical configuration imposed on the circular cross section of the outflow tract. The membranous interventricular septum is formed of cushion material in the space bounded by the outflow tract septum, interventricular septum, and the fused AV cushion and right outflow tract cushion. The results of this study are consistent with the assertion that functional separation of the aortic and pulmonary outflow tracts precedes anatomic septation, and that anatomic septation is brought about by mechanical modeling of developing myocardium and endocardial cushion material.