Development of the Endocardium
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Chapter Xi the Circulatory System and Blood
CHAPTER XI THE CIRCULATORY SYSTEM AND BLOOD Page General characterlstlcs______ __ __ _ __ __ __ __ __ __ _ 239 of these organs are independent of the beating of The pericardium ___ __ __ __ 239 the principal heart, and their primary function is The heart. _____ __ __ 240 Physiology of the heart.______________________________________________ 242 to oscillate the blood within the pallial sinuses. Automatism of heart beat. _ 242 The pacemaker system_ 245 THE PERICARDIUM Methods of study of heart beat_____________________________________ 247 Frequency of beat___ __ __ _ 248 Extracardlac regulatlon____ __ __ _ 250 The heart is located in the pericardium, a thin Effects of mineral salts and drugs___________________________________ 251 Blood vessels_ __ ___ _ 253 walled chamber between the visceral mass and the The arterial system______ __ __ ___ __ __ __ __ __ 253 adductor muscle (fig. 71). In a live oyster the The venous system_________________________________________________ 254 location of the heart is indicated by the throbbing The accessory heart._____________ 258 The blood______ __ __ __ __ __ __ __ 259 of the wall of the pericardium on the left side. Color of blood_ __ __ 261 Here the pericardium wall lies directly under the The hyaline cells___________________________________________________ 261 The granular cells .______________________________________ 262 shell. On the right side the promyal chamber Specific gravity of blood____________________________________________ 265 extends down over the heart region and the mantle Serology ___ __________ __________________ ____ __ ______________________ 265 Bibliography __ __ __ __ __ __ __ 266 separates the pericardium wall from the shell. The cavity in which the heart is lodged is slightly A heart, arteries, veins, and open sinuses form asymmetrical; on the right side it extends farther the circulatory system of oysters and other bi along the anterior part of the adductor muscle valves. -
The Ventricles
Guest Editorial Evolution of the Ventricles Solomon Victor, FRCS, FRCP We studied the evolution of ventricles by macroscopic examination of the hearts of Vijaya M. Nayak, MS marine cartilaginous and bony fish, and by angiocardiography and gross examination of Raveen Rajasingh, MPhil the hearts of air-breathing freshwater fish, frogs, turtles, snakes, and crocodiles. A right-sided, thin-walled ventricular lumen is seen in the fish, frog, turtle, and snake. In fish, there is external symmetry of the ventricle, internal asymmetry, and a thick- walled left ventricle with a small inlet chamber. In animals such as frogs, turtles, and snakes, the left ventricle exists as a small-cavitied contractile sponge. The high pressure generated by this spongy left ventricle, the direction of the jet, the ventriculoarterial ori- entation, and the bulbar spiral valve in the frog help to separate the systemic and pul- monary circulations. In the crocodile, the right aorta is connected to the left ventricle, and there is a complete interventricular septum and an improved left ventricular lumen when compared with turtles and snakes. The heart is housed in a rigid pericardial cavity in the shark, possibly to protect it from changing underwater pressure. The pericardial cavity in various species permits move- ments of the heart-which vary depending on the ventriculoarterial orientation and need for the ventricle to generate torque or spin on the ejected blood- that favor run-off into the appropriate arteries and their branches. In the lower species, it is not clear whether the spongy myocardium contributes to myocardial oxygenation. In human beings, spongy myocardium constitutes a rare form of congenital heart disease. -
Genetic and Flow Anomalies in Congenital Heart Disease
Published online: 2021-05-10 AIMS Genetics, 3(3): 157-166. DOI: 10.3934/genet.2016.3.157 Received: 01 July 2016 Accepted: 16 August 2016 Published: 23 August 2016 http://www.aimspress.com/journal/Genetics Review Genetic and flow anomalies in congenital heart disease Sandra Rugonyi* Department of Biomedical Engineering, Oregon Health & Science University, 3303 SW Bond Ave. M/C CH13B, Portland, OR 97239, USA * Correspondence: Email: [email protected]; Tel: +1-503-418-9310; Fax: +1-503-418-9311. Abstract: Congenital heart defects are the most common malformations in humans, affecting approximately 1% of newborn babies. While genetic causes of congenital heart disease have been studied, only less than 20% of human cases are clearly linked to genetic anomalies. The cause for the majority of the cases remains unknown. Heart formation is a finely orchestrated developmental process and slight disruptions of it can lead to severe malformations. Dysregulation of developmental processes leading to heart malformations are caused by genetic anomalies but also environmental factors including blood flow. Intra-cardiac blood flow dynamics plays a significant role regulating heart development and perturbations of blood flow lead to congenital heart defects in animal models. Defects that result from hemodynamic alterations recapitulate those observed in human babies, even those due to genetic anomalies and toxic teratogen exposure. Because important cardiac developmental events, such as valve formation and septation, occur under blood flow conditions while the heart is pumping, blood flow regulation of cardiac formation might be a critical factor determining cardiac phenotype. The contribution of flow to cardiac phenotype, however, is frequently ignored. -
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Folia Morphol. Vol. 78, No. 2, pp. 283–289 DOI: 10.5603/FM.a2018.0077 O R I G I N A L A R T I C L E Copyright © 2019 Via Medica ISSN 0015–5659 journals.viamedica.pl Observations of foetal heart veins draining directly into the left and right atria J.H. Kim1, O.H. Chai1, C.H. Song1, Z.W. Jin2, G. Murakami3, H. Abe4 1Department of Anatomy and Institute of Medical Sciences, Chonbuk National University Medical School, Jeonju, Korea 2Department of Anatomy, Wuxi Medical School, Jiangnan University, Wuxi, China 3Division of Internal Medicine, Jikou-kai Clinic of Home Visits, Sapporo, Japan 4Department of Anatomy, Akita University School of Medicine, Akita, Japan [Received: 19 June 2018; Accepted: 8 August 2018] Evaluation of semiserial sections of 14 normal hearts from human foetuses of gestational age 25–33 weeks showed that all of these hearts contained thin veins draining directly into the atria (maximum, 10 veins per heart). Of the 75 veins in these 14 hearts, 55 emptied into the right atrium and 20 into the left atrium. These veins were not accompanied by nerves, in contrast to tributaries of the great cardiac vein, and were negative for both smooth muscle actin (SMA) and CD34. However, the epithelium and venous wall of the anterior cardiac vein, the thickest of the direct draining veins, were strongly positive for SMA and CD34, respectively. In general, developing fibres in the vascular wall were positive for CD34, while the endothelium of the arteries and veins was strongly positive for the present DAKO antibody of SMA. -
PERCEVAL SUTURELESS AORTIC HEART VALVE Instructions for Use
HVV_LS-850-0002 Rev X03 PERCEVAL SUTURELESS AORTIC HEART VALVE Instructions for Use CAUTION: Federal Law (USA) restricts the device to sale by or on the order of a physician. SYMBOLS CAUTION: SEE MANUAL FOR INSTRUCTIONS/WARNINGS CONTENTS STERILIZED USING ASEPTIC PROCESSING TECHNIQUE USE BY STORE BETWEEN 5°C AND 25°C SINGLE USE ONLY DO NOT RESTERILIZE CATALOGUE NUMBER SERIAL NUMBER SIZE MANUFACTURER QUANTITY INCLUDED IN PACKAGE DO NOT USE IF PACKAGE IS DAMAGED THIS WAY UP MR CONDITIONAL 1. DESCRIPTION Perceval is a bioprosthetic valve designed to replace a diseased native or a malfunctioning prosthetic aortic valve via open heart surgery, with the unique characteristic of allowing sutureless positioning and anchoring at the implant site. The choice of materials and configuration ensures the device biocompatibility and hemocompatibility. The Perceval prosthesis consists of a tissue component made from bovine pericardium and a self-expandable Nitinol stent, which has the dual role of supporting the valve and fixing it in place. Perceval tissue heart valve is supplied unmounted. Prior to implantation the prosthesis diameter is reduced to a suitable size for loading it on the holder. The valve is then positioned and released in the aortic root, where the stent design and its ability to apply a radial force to the annulus allow stable anchoring of the device. 2. AVAILABLE MODELS The Perceval aortic model is available in four sizes: size S, size M, size L, and size XL. The prosthesis height is 31.0, 33.0, 35.5, and 37.5 mm, respectively. Each size is suitable for a range of aortic annuli and sinotubular junction (STJ) diameters. -
Location of the Human Sinus Node in Black Africans
ogy: iol Cu ys r h re P n t & R y e s Anatomy & Physiology: Current m e o a t r a c n h A Research Meneas et al., Anat Physiol 2017, 7:5 ISSN: 2161-0940 DOI: 10.4172/2161-0940.1000279 Research article Open Access Location of the Human Sinus Node in Black Africans Meneas GC*, Yangni-Angate KH, Abro S and Adoubi KA Department of Cardiovascular and Thoracic Diseases, Bouake Teaching Hospital, Cote d’Ivoire, West-Africa *Corresponding author: Meneas GC, Department of Cardiovascular and Thoracic Diseases, Bouake Teaching Hospital, Cote d’Ivoire, West-Africa, Tel: +22507701532; E-mail: [email protected] Received Date: August 15, 2017; Accepted Date: August 22, 2017; Published Date: August 29, 2017 Copyright: © 2017 Meneas GC, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited. Abstract Objective: The purpose of this study was to describe, in 45 normal hearts of black Africans adults, the location of the sinoatrial node. Methods: After naked eye observation of the external epicardial area of the sinus node classically described as cavoatrial junction (CAJ), a histological study of the sinus node area was performed. Results: This study concluded that the sinus node is indistinguishable to the naked eye (97.77% of cases), but still identified histologically at the CAJ in the form of a cluster of nodal cells surrounded by abundant connective tissues. It is distinguished from the Myocardial Tissue. -
Cardiovascular System ANS 215 Physiology and Anatomy of Domesticated Animals
Cardiovascular System ANS 215 Physiology and Anatomy of Domesticated Animals I. Structure and Function A. Heart is a cone-shaped, hollow, muscular structure located in the thorax. B. Larger arteries and veins are continuous with the heart as its base. 1. Base is directed upward (dorsal) and forward (cranial). 2. Opposite end of the cone is known as the apex C. Membrane around the heart is known as the pericardium 1. Membrane next to hear fuses with the heart muscle and is called the visceral pericardium or epicardium 2. outer membrane is parietal pericardium 3. apex is free 4. Inflammation of the pericardium is called pericarditis. a. increase in fluid in pericardium b. traumatic pericarditis (hardware) disease in cattle 1 Left view of bovine thorax and abdomen showing location of the heart relative to the stomach. Foreign objects (nails, wire), sometimes ingested by cattle, accumulate in the reticulum ( one of the bovine forestomachs). Contraction of the reticulum can force pointed objects through the reticulum wall and the diaphragm, causing final penetration of the pericardium and subsequent inflammation (pericarditis). 2 D. Myocardium 1. Muscular part of the heart which forms the walls for the chambers 2. Heart chambers (4) divided into left and right side of the heart a. Each side has an atrium and ventricle. b. Each atrium has an extension known as the auricle. c. Atria receive blood from veins and ventricles receive blood from atria. Computer image of a cross sectional view of the heart at the ventricular level showing the chordae tendinae and the relative thickness of the myocardium. -
Growth and Remodeling of Atrioventricular Heart Valves: a Potential Target for Pharmacological Treatment? Manuel K
Available online at www.sciencedirect.com Current Opinion in ScienceDirect Biomedical Engineering Growth and remodeling of atrioventricular heart valves: A potential target for pharmacological treatment? Manuel K. Rausch Abstract backflow or regurgitation of blood. These vital functions Atrioventricular heart valves, that is, the mitral valve and the depend on a well-orchestrated interplay between the tricuspid valve, play vital roles in our cardiovascular system. valves’ components, that is, the valve leaflets, the valve Disease of these valves is, therefore, a significant source of annulus, the chordae tendineae, and the papillary morbidity and mortality. Unfortunately, current treatment op- muscles, refer Figure 1a. In this role, their central tions are suboptimal with significant rates of failure. It was only components, the valve leaflets, are exposed to hemo- recently that we have begun to appreciate that the atrioven- dynamic shear stresses, radial tensile forces at the tricular heart valve leaflets are not just passive flaps, but chordal insertion sites, circumferential tensile forces at actively (mal)adapting tissues. This discovery sheds new light their annular insertion, biaxial stretch due to the on disease mechanisms and provides, thus, possible path- transvalvular pressure, and compressive forces in the ways to new treatments. In this current opinion piece, we coaptation zone. This complex loading regime is cycli- examine the state of our knowledge about the (mal)adaptive cally repeated with every heartbeat for billions of times mechanisms (physiological and pathological growth and throughout our lifetime [1,2]. Ostensibly, these loading remodeling) of the atrioventricular heart valves. Furthermore, modes determine the valves’ microstructure and we review the evidence that suggests that valve maladaptation consequently their mechanical properties [3]. -
4B. the Heart (Cor) 1
Henry Gray (1821–1865). Anatomy of the Human Body. 1918. 4b. The Heart (Cor) 1 The heart is a hollow muscular organ of a somewhat conical form; it lies between the lungs in the middle mediastinum and is enclosed in the pericardium (Fig. 490). It is placed obliquely in the chest behind the body of the sternum and adjoining parts of the rib cartilages, and projects farther into the left than into the right half of the thoracic cavity, so that about one-third of it is situated on the right and two-thirds on the left of the median plane. Size.—The heart, in the adult, measures about 12 cm. in length, 8 to 9 cm. in breadth at the 2 broadest part, and 6 cm. in thickness. Its weight, in the male, varies from 280 to 340 grams; in the female, from 230 to 280 grams. The heart continues to increase in weight and size up to an advanced period of life; this increase is more marked in men than in women. Component Parts.—As has already been stated (page 497), the heart is subdivided by 3 septa into right and left halves, and a constriction subdivides each half of the organ into two cavities, the upper cavity being called the atrium, the lower the ventricle. The heart therefore consists of four chambers, viz., right and left atria, and right and left ventricles. The division of the heart into four cavities is indicated on its surface by grooves. The atria 4 are separated from the ventricles by the coronary sulcus (auriculoventricular groove); this contains the trunks of the nutrient vessels of the heart, and is deficient in front, where it is crossed by the root of the pulmonary artery. -
Sudden Death in Racehorses: Postmortem Examination Protocol
VDIXXX10.1177/1040638716687004Sudden death in racehorsesDiab et al. 687004research-article2017 Special Issue Journal of Veterinary Diagnostic Investigation 1 –8 Sudden death in racehorses: postmortem © 2017 The Author(s) Reprints and permissions: sagepub.com/journalsPermissions.nav examination protocol DOI: 10.1177/1040638716687004 jvdi.sagepub.com Santiago S. Diab,1 Robert Poppenga, Francisco A. Uzal Abstract. In racehorses, sudden death (SD) associated with exercise poses a serious risk to jockeys and adversely affects racehorse welfare and the public perception of horse racing. In a majority of cases of exercise-associated sudden death (EASD), there are no gross lesions to explain the cause of death, and an examination of the cardiovascular system and a toxicologic screen are warranted. Cases of EASD without gross lesions are often presumed to be sudden cardiac deaths (SCD). We describe an equine SD autopsy protocol, with emphasis on histologic examination of the heart (“cardiac histology protocol”) and a description of the toxicologic screen performed in racehorses in California. By consistently utilizing this standardized autopsy and cardiac histology protocol, the results and conclusions from postmortem examinations will be easier to compare within and across institutions over time. The generation of consistent, reliable, and comparable multi-institutional data is essential to improving the understanding of the cause(s) and pathogenesis of equine SD, including EASD and SCD. Key words: Cardiac autopsy; equine; exercise; racehorses; -
Endocardial Cushion and Myocardial Defects After Cardiac Myocyte-Specific Conditional Deletion of the Bone Morphogenetic Protein Receptor ALK3
Endocardial cushion and myocardial defects after cardiac myocyte-specific conditional deletion of the bone morphogenetic protein receptor ALK3 Vinciane Gaussin*†, Tom Van de Putte‡, Yuji Mishina§, Mark C. Hanks¶, An Zwijsen‡, Danny Huylebroeck‡, Richard R. Behringerʈ, and Michael D. Schneider*,** *Center for Cardiovascular Development, Baylor College of Medicine, Houston, TX 77030; ‡Flanders Interuniversity Institute for Biotechnology (VIB07), K.U. Leuven, 3000 Leuven, Belgium; §National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709; ¶Procter and Gamble Pharmaceuticals Health Care Research Center, 8700 Mason Montgomery Road, Mason, OH 45040; and ʈUniversity of Texas–M. D. Anderson Cancer Center, Houston, TX 77030 Edited by Eric N. Olson, University of Texas Southwestern Medical Center, Dallas, TX, and approved December 31, 2001 (received for review July 26, 2001) Receptors for bone morphogenetic proteins (BMPs), members of velopment, whereas ALK6 is absent from the heart at mid- the transforming growth factor- (TGF) superfamily, are persis- gestation (17). The developing heart also expresses ALK2͞ tently expressed during cardiac development, yet mice lacking type ActRIA (5, 18), which can function as a type I BMP receptor II or type IA BMP receptors die at gastrulation and cannot be used with preference for BMP6 and -7 (19). ALK3, ALK2, and to assess potential later roles in creation of the heart. Here, we BMPR-II are each essential for gastrulation and mesoderm used a Cre͞lox system for cardiac myocyte-specific deletion of the formation (18, 20, 21); mice lacking just BMP4 also fail to type IA BMP receptor, ALK3. ALK3 was specifically required at progress, typically, beyond the egg cylinder stage (22). -
Cardiovascular System Heart Development Cardiovascular System Heart Development
Cardiovascular System Heart Development Cardiovascular System Heart Development In human embryos, the heart begins to beat at approximately 22-23 days, with blood flow beginning in the 4th week. The heart is one of the earliest differentiating and functioning organs. • This emphasizes the critical nature of the heart in distributing blood through the vessels and the vital exchange of nutrients, oxygen, and wastes between the developing baby and the mother. • Therefore, the first system that completes its development in the embryo is called cardiovascular system. https://www.slideshare.net/DrSherifFahmy/intraembryonic-mesoderm-general-embryology Mesoderm is one of the three • Connective tissue primary germ layers that • Smooth and striated muscle • Cardiovascular System differentiates early in • Kidneys development that collectively • Spleen • Genital organs, ducts gives rise to all subsequent • Adrenal gland cortex tissues and organs. The cardiovascular system begins to develop in the third week of gestation. Blood islands develop in the newly formed mesoderm, and consist of (a) a central group of haemoblasts, the embryonic precursors of blood cells; (b) endothelial cells. Development of the heart and vascular system is often described together as the cardiovascular system. Development begins very early in mesoderm both within (embryonic) and outside (extra embryonic, vitelline, umblical and placental) the embryo. Vascular development occurs in many places. • Blood islands coalesce to form a vascular plexus. Preferential channels form arteries and veins. • Day 17 - Blood islands form first in the extra-embryonic mesoderm • Day 18 - Blood islands form next in the intra-embryonic mesoderm • Day 19 - Blood islands form in the cardiogenic mesoderm and coalesce to form a pair of endothelial heart tubes Development of a circulation • A circulation is established during the 4th week after the myocardium is differentiated.