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In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek kardia meaning heart, and Latin vascula meaning vess... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 0 |
The network of blood vessels are the great vessels of the heart including large elastic arteries, and large veins; other arteries, smaller arterioles, capillaries that join with venules (small veins), and other veins. The circulatory system is closed in vertebrates, which means that the blood never leaves the network o... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 2 |
In vertebrates, the lymphatic system is complementary to the circulatory system. The lymphatic system carries excess plasma (filtered from the circulatory system capillaries as interstitial fluid between cells) away from the body tissues via accessory routes that return excess fluid back to blood circulation as lymph. ... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 6 |
The lymphatic system also works with the immune system. The circulation of lymph takes much longer than that of blood and, unlike the closed (blood) circulatory system, the lymphatic system is an open system. Some sources describe it as a secondary circulatory system. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 7 |
The circulatory system can be affected by many cardiovascular diseases. Cardiologists are medical professionals which specialise in the heart, and cardiothoracic surgeons specialise in operating on the heart and its surrounding areas. Vascular surgeons focus on disorders of the blood vessels, and lymphatic vessels. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 8 |
Structure
The circulatory system includes the heart, blood vessels, and blood. The cardiovascular system in all vertebrates, consists of the heart and blood vessels. Some sources use the terms cardiovascular system and vascular system interchangeably with circulatory system. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 9 |
The circulatory system is further divided into two major circuits – a pulmonary circulation, and a systemic circulation. The pulmonary circulation is a circuit loop from the right heart taking deoxygenated blood to the lungs where it is oxygenated and returned to the left heart. The systemic circulation is a circuit lo... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 10 |
. The systemic circulation can also be defined as two parts – a macrocirculation and a microcirculation. An average adult contains five to six quarts (roughly 4.7 to 5.7 liters) of blood, accounting for approximately 7% of their total body weight. Blood consists of plasma, red blood cells, white blood cells, and platel... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 11 |
Further circulatory routes are associated, such as the coronary circulation to the heart itself, the cerebral circulation to the brain, renal circulation to the kidneys, and bronchial circulation to the bronchi in the lungs. The human circulatory system is closed, meaning that the blood is contained within the vascular... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 12 |
. Nutrients travel through tiny blood vessels of the microcirculation to reach organs. The lymphatic system is an essential subsystem of the circulatory system consisting of a network of lymphatic vessels, lymph nodes, organs, tissues and circulating lymph. This subsystem is an open system. A major function is to carry... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 13 |
Pulmonary circulation
Oxygen-deprived blood from the superior and inferior vena cava enters the right atrium of the heart and flows through the tricuspid valve (right atrioventricular valve) into the right ventricle, from which it is then pumped through the pulmonary semilunar valve into the pulmonary artery to the lun... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 16 |
Systemic circulation
The systemic circulation is a circuit loop that delivers oxygenated blood from the left heart to the rest of the body through the aorta. Deoxygenated blood is returned in the systemic circulation to the right heart via two large veins, the inferior vena cava and superior vena cava, where it is pump... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 18 |
Arteries
Oxygenated blood enters the systemic circulation when leaving the left ventricle, via the aortic semilunar valve. The first part of the systemic circulation is the aorta, a massive and thick-walled artery. The aorta arches and gives branches supplying the upper part of the body after passing through the aortic... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 20 |
The walls of the aorta are elastic. This elasticity helps to maintain the blood pressure throughout the body. When the aorta receives almost five litres of blood from the heart, it recoils and is responsible for pulsating blood pressure. As the aorta branches into smaller arteries, their elasticity goes on decreasing a... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 21 |
Capillaries
Arteries branch into small passages called arterioles and then into the capillaries. The capillaries merge to bring blood into the venous system. The total length of muscle capillaries in a 70 kg human is estimated to be between 9,000 and 19,000 km. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 22 |
Veins
Capillaries merge into venules, which merge into veins. The venous system feeds into the two major veins: the superior vena cava – which mainly drains tissues above the heart – and the inferior vena cava – which mainly drains tissues below the heart. These two large veins empty into the right atrium of the heart. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 23 |
Portal veins
The general rule is that arteries from the heart branch out into capillaries, which collect into veins leading back to the heart. Portal veins are a slight exception to this. In humans, the only significant example is the hepatic portal vein which combines from capillaries around the gastrointestinal tract... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 24 |
The coronary circulation system provides a blood supply to the heart muscle itself. The coronary circulation begins near the origin of the aorta by two coronary arteries: the right coronary artery and the left coronary artery. After nourishing the heart muscle, blood returns through the coronary veins into the coronary... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 26 |
The brain has a dual blood supply, an anterior and a posterior circulation from arteries at its front and back. The anterior circulation arises from the internal carotid arteries to supply the front of the brain. The posterior circulation arises from the vertebral arteries, to supply the back of the brain and brainstem... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 29 |
. The circulation from the front and the back join (anastomise) at the circle of Willis. The neurovascular unit, composed of various cells and vasculature channels within the brain, regulates the flow of blood to activated neurons in order to satisfy their high energy demands. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 30 |
The development of the circulatory system starts with vasculogenesis in the embryo. The human arterial and venous systems develop from different areas in the embryo. The arterial system develops mainly from the aortic arches, six pairs of arches that develop on the upper part of the embryo. The venous system arises fro... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 33 |
. Fetal circulation begins within the 8th week of development. Fetal circulation does not include the lungs, which are bypassed via the truncus arteriosus. Before birth the fetus obtains oxygen (and nutrients) from the mother through the placenta and the umbilical cord. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 34 |
Arteries
The human arterial system originates from the aortic arches and from the dorsal aortae starting from week 4 of embryonic life. The first and second aortic arches regress and form only the maxillary arteries and stapedial arteries respectively. The arterial system itself arises from aortic arches 3, 4 and 6 (ao... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 35 |
The dorsal aortae, present on the dorsal side of the embryo, are initially present on both sides of the embryo. They later fuse to form the basis for the aorta itself. Approximately thirty smaller arteries branch from this at the back and sides. These branches form the intercostal arteries, arteries of the arms and leg... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 36 |
. Branches to the sides of the aorta will form the definitive renal, suprarenal and gonadal arteries. Finally, branches at the front of the aorta consist of the vitelline arteries and umbilical arteries. The vitelline arteries form the celiac, superior and inferior mesenteric arteries of the gastrointestinal tract. Aft... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 37 |
Veins
The human venous system develops mainly from the vitelline veins, the umbilical veins and the cardinal veins, all of which empty into the sinus venosus.
Function
About 98.5% of the oxygen in a sample of arterial blood in a healthy human, breathing air at sea-level pressure, is chemically combined with hemoglobin... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 38 |
Clinical significance
Many diseases affect the circulatory system. These include a number of cardiovascular diseases, affecting the heart and blood vessels; hematologic diseases that affect the blood, such as anemia, and lymphatic diseases affecting the lymphatic system. Cardiologists are medical professionals which sp... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 39 |
Many of these diseases are called "lifestyle diseases" because they develop over time and are related to a person's exercise habits, diet, whether they smoke, and other lifestyle choices a person makes. Atherosclerosis is the precursor to many of these diseases. It is where small atheromatous plaques build up in the wa... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 41 |
. This may eventually grow or rupture to occlude the arteries. It is also a risk factor for acute coronary syndromes, which are diseases that are characterised by a sudden deficit of oxygenated blood to the heart tissue. Atherosclerosis is also associated with problems such as aneurysm formation or splitting ("dissecti... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 42 |
Another major cardiovascular disease involves the creation of a clot, called a "thrombus". These can originate in veins or arteries. Deep venous thrombosis, which mostly occurs in the legs, is one cause of clots in the veins of the legs, particularly when a person has been stationary for a long time. These clots may em... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 43 |
Other more invasive means can also be used. A cannula or catheter inserted into an artery may be used to measure pulse pressure or pulmonary wedge pressures. Angiography, which involves injecting a dye into an artery to visualise an arterial tree, can be used in the heart (coronary angiography) or brain. At the same ti... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 48 |
. An MRI may be used to image arteries, called an MRI angiogram. For evaluation of the blood supply to the lungs a CT pulmonary angiogram may be used. Vascular ultrasonography may be used to investigate vascular diseases affecting the venous system and the arterial system including the diagnosis of stenosis, thrombosis... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 49 |
Hemolymph fills all of the interior hemocoel of the body and surrounds all cells. Hemolymph is composed of water, inorganic salts (mostly sodium, chloride, potassium, magnesium, and calcium), and organic compounds (mostly carbohydrates, proteins, and lipids). The primary oxygen transporter molecule is hemocyanin.
There... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 56 |
Closed circulatory system
The circulatory systems of all vertebrates, as well as of annelids (for example, earthworms) and cephalopods (squids, octopuses and relatives) always keep their circulating blood enclosed within heart chambers or blood vessels and are classified as closed, just as in humans. Still, the systems... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 57 |
In fish, the system has only one circuit, with the blood being pumped through the capillaries of the gills and on to the capillaries of the body tissues. This is known as single cycle circulation. The heart of fish is, therefore, only a single pump (consisting of two chambers).
In amphibians and most reptiles, a double... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 58 |
In reptiles, the ventricular septum of the heart is incomplete and the pulmonary artery is equipped with a sphincter muscle. This allows a second possible route of blood flow. Instead of blood flowing through the pulmonary artery to the lungs, the sphincter may be contracted to divert this blood flow through the incomp... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 59 |
Circulatory systems are absent in some animals, including flatworms. Their body cavity has no lining or enclosed fluid. Instead, a muscular pharynx leads to an extensively branched digestive system that facilitates direct diffusion of nutrients to all cells. The flatworm's dorso-ventrally flattened body shape also rest... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 63 |
. Oxygen can diffuse from the surrounding water into the cells, and carbon dioxide can diffuse out. Consequently, every cell is able to obtain nutrients, water and oxygen without the need of a transport system. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 64 |
The earliest known writings on the circulatory system are found in the Ebers Papyrus (16th century BCE), an ancient Egyptian medical papyrus containing over 700 prescriptions and remedies, both physical and spiritual. In the papyrus, it acknowledges the connection of the heart to the arteries. The Egyptians thought air... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 67 |
. From the heart, the air travelled to every member through the arteries. Although this concept of the circulatory system is only partially correct, it represents one of the earliest accounts of scientific thought. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 68 |
. The first major ancient Greek research into the circulatory system was completed by Plato in the Timaeus, who argues that blood circulates around the body in accordance with the general rules that govern the motions of the elements in the body; accordingly, he does not place much importance in the heart itself. The v... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 70 |
. However, their function was not properly understood then. Because blood pools in the veins after death, arteries look empty. Ancient anatomists assumed they were filled with air and that they were for the transport of air. | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 71 |
The Greek physician, Herophilus, distinguished veins from arteries but thought that the pulse was a property of arteries themselves. Greek anatomist Erasistratus observed that arteries that were cut during life bleed. He ascribed the fact to the phenomenon that air escaping from an artery is replaced with blood that en... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 72 |
. Blood flowed from both creating organs to all parts of the body where it was consumed and there was no return of blood to the heart or liver. The heart did not pump blood around, the heart's motion sucked blood in during diastole and the blood moved by the pulsation of the arteries themselves | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 74 |
. Galen believed that the arterial blood was created by venous blood passing from the left ventricle to the right by passing through 'pores' in the interventricular septum, air passed from the lungs via the pulmonary artery to the left side of the heart. As the arterial blood was created 'sooty' vapors were created and... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 75 |
. While also refining Galen's erroneous theory of the pulse, Avicenna provided the first correct explanation of pulsation: "Every beat of the pulse comprises two movements and two pauses. Thus, expansion : pause : contraction : pause. [...] The pulse is a movement in the heart and arteries ... which takes the form of a... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 77 |
In addition, Ibn al-Nafis had an insight into what later became a larger theory of the capillary circulation. He stated that "there must be small communications or pores (manafidh in Arabic) between the pulmonary artery and vein," a prediction that preceded the discovery of the capillary system by more than 400 years. ... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 81 |
Michael Servetus was the first European to describe the function of pulmonary circulation, although his achievement was not widely recognized at the time, for a few reasons. He firstly described it in the "Manuscript of Paris" (near 1546), but this work was never published. And later he published this description, but ... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 82 |
. Most importantly, he argued that the beat of the heart produced a continuous circulation of blood through minute connections at the extremities of the body. This is a conceptual leap that was quite different from Ibn al-Nafis' refinement of the anatomy and bloodflow in the heart and lungs." This work, with its essent... | Circulatory system | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Circulatory_system | 86 |
A congenital heart defect (CHD), also known as a congenital heart anomaly, congenital cardiovascular malformation, and congenital heart disease, is a defect in the structure of the heart or great vessels that is present at birth. A congenital heart defect is classed as a cardiovascular disease. Signs and symptoms depen... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 0 |
. Symptoms can vary from none to life-threatening. When present, symptoms are variable and may include rapid breathing, bluish skin (cyanosis), poor weight gain, and feeling tired. CHD does not cause chest pain. Most congenital heart defects are not associated with other diseases. A complication of CHD is heart failure... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 1 |
Congenital heart defects are the most common birth defect. In 2015, they were present in 48.9 million people globally. They affect between 4 and 75 per 1,000 live births, depending upon how they are diagnosed. In about 6 to 19 per 1,000 they cause a moderate to severe degree of problems. Congenital heart defects are th... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 2 |
The cause of a congenital heart defect is often unknown. Risk factors include certain infections during pregnancy such as rubella, use of certain medications or drugs such as alcohol or tobacco, parents being closely related, or poor nutritional status or obesity in the mother. Having a parent with a congenital heart d... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 3 |
. Congenital heart defects are divided into two main groups: cyanotic heart defects and non-cyanotic heart defects, depending on whether the child has the potential to turn bluish in color. The defects may involve the interior walls of the heart, the heart valves, or the large blood vessels that lead to and from the he... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 4 |
Congenital heart defects are partly preventable through rubella vaccination, the adding of iodine to salt, and the adding of folic acid to certain food products. Some defects do not need treatment. Others may be effectively treated with catheter based procedures or heart surgery. Occasionally a number of operations may... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 5 |
Signs and symptoms are related to type and severity of the heart defect. Symptoms frequently present early in life, but it is possible for some CHDs to go undetected throughout life. Some children have no signs while others may exhibit shortness of breath, cyanosis, fainting, heart murmur, under-development of limbs an... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 7 |
The genes regulating the complex developmental sequence have only been partly elucidated. Some genes are associated with specific defects. A number of genes have been associated with cardiac manifestations. Mutations of a heart muscle protein, α-myosin heavy chain (MYH6) are associated with atrial septal defects. Sever... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 13 |
. The transcription factor GATA4 forms a complex with the TBX5 which interacts with MYH6. Another factor, the homeobox (developmental) gene, NKX2-5 also interacts with MYH6. Mutations of all these proteins are associated with both atrial and ventricular septal defects; In addition, NKX2-5 is associated with defects in ... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 14 |
. The Wnt signaling co-factors BCL9, BCL9L and PYGO might be part of these molecular pathways, as when their genes are mutated, this causes phenotypes similar to the features present in Holt-Oram syndrome. Another T-box gene, TBX1, is involved in velo-cardio-facial syndrome DiGeorge syndrome, the most common deletion w... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 15 |
The notch signaling pathway, a regulatory mechanism for cell growth and differentiation, plays broad roles in several aspects of cardiac development. Notch elements are involved in determination of the right and left sides of the body plan, so the directional folding of the heart tube can be impacted. Notch signaling i... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 16 |
. It is also involved in the development of the ventricular wall and the connection of the outflow tract to the great vessels. Mutations in the gene for one of the notch ligands, Jagged1, are identified in the majority of examined cases of arteriohepatic dysplasia (Alagille syndrome), characterized by defects of the gr... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 17 |
. Though less than 1% of all cases, where no defects are found in the Jagged1 gene, defects are found in Notch2 gene. In 10% of cases, no mutation is found in either gene. For another member of the gene family, mutations in the Notch1 gene are associated with bicuspid aortic valve, a valve with two leaflets instead of ... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 18 |
Mutations of a cell regulatory mechanism, the Ras/MAPK pathway are responsible for a variety of syndromes, including Noonan syndrome, LEOPARD syndrome, Costello syndrome and cardiofaciocutaneous syndrome in which there is cardiac involvement. While the conditions listed are known genetic causes, there are likely many o... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 19 |
Being overweight or obese increases the risk of congenital heart disease. Additionally, as maternal obesity increases, the risk of heart defects also increases. A distinct physiological mechanism has not been identified to explain the link between maternal obesity and CHD, but both pre-pregnancy folate deficiency and d... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 21 |
Twins and Multiple Births
Congenital heart defects happen more often in twins than in single babies. Monochorionic twins, who share a placenta, have a greater risk of these heart defects compared to dichorionic twins, who have their own placentas. A systematic review and meta-analysis of four studies conducted in 2007 ... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 22 |
. On day 19 of development, a pair of vascular elements, the "endocardial tubes", form. The tubes fuse when cells between then undergo programmed death and cells from the first heart field migrate to the tube, and form a ring of heart cells (myocytes) around it by day 21. On day 22, the heart begins to beat and by day ... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 25 |
At day 22, the circulatory system is bilaterally symmetrical with paired vessels on each side and the heart consisting of a simple tube located in the midline of the body layout. The portions that will become the atria and will be located closest to the head are the most distant from the head. From days 23 through 28, ... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 26 |
On day 28, areas of tissue in the heart tube begin to expand inwards; after about two weeks, these expansions (the membranous "septum primum" and the muscular "endocardial cushions") fuse to form the four chambers of the heart. A failure to fuse properly will result in a defect that may allow blood to leak between cham... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 27 |
. After this happens, cells that have migrated from the neural crest begin to divide the bulbus cordis. The main outflow tract is divided in two by the growth of a spiraling septum, becoming the great vessels—the ascending segment of the aorta and the pulmonary trunk. If the separation is incomplete, the result is a "p... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 28 |
. The vessels may be reversed ("transposition of the great vessels"). The two halves of the split tract must migrate into the correct positions over the appropriate ventricles. A failure may result in some blood flowing into the wrong vessel (e.g. overriding aorta). The four-chambered heart and the great vessels have f... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 29 |
. Two structures exist to shunt blood flow away from the lungs to compensate. Cells in part of the septum primum die, creating a hole while new muscle cells (the "septum secundum") grow along the right atrial side of the septum primum except for one region, leaving a gap through which blood can pass from the right atri... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 30 |
The ductus arteriosus stays open because of circulating factors including prostaglandins. The foramen ovale stays open because of the flow of blood from the right atrium to the left atrium. As the lungs expand, blood flows easily through the lungs and the membranous portion of the foramen ovale (the septum primum) flop... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 32 |
. If the closure is incomplete, the result is a patent foramen ovale. The two flaps may fuse, but many adults have a foramen ovale that stays closed only because of the pressure difference between the atria. | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 33 |
Theories
Rokitansky (1875) explained congenital heart defects as breaks in heart development at various ontogenesis stages. Spitzer (1923) treats them as returns to one of the phylogenesis stages. Krimski (1963), synthesizing two previous points of view, considered congenital heart diseases as a stop of development at ... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 34 |
Diagnosis
Many congenital heart defects can be diagnosed prenatally by fetal echocardiography. This is a test which can be done during the second trimester of pregnancy, when the woman is about 18–24 weeks pregnant. It can be an abdominal ultrasound or transvaginal ultrasound.
If a baby is born with cyanotic heart dise... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 35 |
Hypoplasia can affect the heart, typically resulting in the underdevelopment of the right ventricle or the left ventricle. This causes only one side of the heart to be capable of pumping blood to the body and lungs effectively. Hypoplasia of the heart is rare but is the most serious form of CHD. It is called hypoplasti... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 39 |
. In both conditions, the presence of a patent ductus arteriosus (and, when hypoplasia affects the right side of the heart, a patent foramen ovale) is vital to the infant's ability to survive until emergency heart surgery can be performed, since without these pathways blood cannot circulate to the body (or lungs, depen... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 40 |
Obstructive defects
Obstructive defects occur when heart valves, arteries, or veins are abnormally narrow or blocked. Common defects include pulmonic stenosis, aortic stenosis, and coarctation of the aorta, with other types such as bicuspid aortic valve stenosis and subaortic stenosis being comparatively rare. Any narr... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 41 |
The septum is a wall of tissue which separates the left heart from the right heart. Defects in the interatrial septum or the interventricular septum allow blood to flow from the left side of the heart to the right, reducing the heart's efficiency. Ventricular septal defects are collectively the most common type of CHD,... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 43 |
Treatment
CHD may require surgery and medications. Medications include diuretics, which aid the body in eliminating water, salts, and digoxin for strengthening the contraction of the heart. This slows the heartbeat and removes some fluid from tissues. Some defects require surgical procedures to restore circulation back... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 50 |
Interventional cardiology now offers minimally invasive alternatives to surgery for some patients. The Melody Transcatheter Pulmonary Valve (TPV), approved in Europe in 2006 and in the U.S. in 2010 under a Humanitarian Device Exemption (HDE), is designed to treat congenital heart disease patients with a dysfunctional c... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 51 |
. The RVOT is the connection between the heart and lungs; once blood reaches the lungs, it is enriched with oxygen before being pumped to the rest of the body. Transcatheter pulmonary valve technology provides a less-invasive means to extend the life of a failed RVOT conduit and is designed to allow physicians to deliv... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 52 |
Supporting people with chronic diseases such as congenital heart disease with emotional problems and mental health is a treatment consideration. Since some people with congenital heart disease have a lower quality of life that is related to their condition, some people may struggle with finding a job, engaging in physi... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 55 |
. An estimated 31% of adults with congenital heart disease also have mood disorders. Psychotherapy may be helpful for treating some people who have congenital heart disease and depression, however further research is needed to determine the best way to reduce depression including the length of treatments required for a... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 56 |
Epidemiology
Heart defects are among the most common birth defect, occurring in 1% of live births (2–3% including bicuspid aortic valve). In 2013, 34.3 million people had CHD. In 2010, they resulted in 223,000 deaths, down from 278,000 deaths in 1990.
For congenital heart defects that arise without a family history (de... | Congenital heart defect | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Congenital_heart_defect | 57 |
Although symptoms vary based on which side of the heart is affected, HF typically presents with shortness of breath, excessive fatigue, and bilateral leg swelling. The severity of the heart failure is mainly decided based on ejection fraction and also measured by the severity of symptoms. Other conditions that have sym... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 1 |
. There are different types of heart failure: right-sided heart failure, which affects the right heart, left-sided heart failure, which affects the left heart, and biventricular heart failure, which affects both sides of the heart. Left-sided heart failure may be present with a reduced ejection fraction or with a pres... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 3 |
Diagnosis is based on symptoms, physical findings, and echocardiography. Blood tests, and a chest x-ray may be useful to determine the underlying cause. Treatment depends on severity and case. For people with chronic, stable, or mild heart failure, treatment usually consists of lifestyle changes, such as not smoking, p... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 4 |
. In heart failure due to left ventricular dysfunction, angiotensin-converting-enzyme inhibitors, angiotensin II receptor blockers (ARBs), or angiotensin receptor-neprilysin inhibitors, along with beta blockers, mineralocorticoid receptor antagonists and SGLT2 inhibitors are recommended. Diuretics may also be prescribe... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 5 |
. Diuretics may also be prescribed to prevent fluid retention and the resulting shortness of breath. Depending on the case, an implanted device such as a pacemaker or implantable cardiac defibrillator may sometimes be recommended. In some moderate or more severe cases, cardiac resynchronization therapy (CRT) or cardia... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 6 |
Heart failure is a common, costly, and potentially fatal condition, and is the leading cause of hospitalization and readmission in older adults. Heart failure often leads to more drastic health impairments than the failure of other, similarly complex organs such as the kidneys or liver. In 2015, it affected about 40 mi... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 8 |
The risk of death in the first year after diagnosis is about 35%, while the risk of death in the second year is less than 10% in those still alive. The risk of death is comparable to that of some cancers. In the United Kingdom, the disease is the reason for 5% of emergency hospital admissions. Heart failure has been kn... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 9 |
. This leads to high filling pressure in the left atrium with fluid accumulation and water retention. Most of the visible signs of heart failure are the result of this fluid accumulation (edema) and the adjective congestion is added to the definition of heart failure. Impaired ejection can lead to inadequate blood flo... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 12 |
Congestion manifests itself particularly in the form of fluid accumulation and swelling (edema), in the form of peripheral edema (causing swollen limbs and feet) and pulmonary edema (causing difficulty breathing) and ascites (swollen abdomen). Pulse pressure, which is the difference between the systolic ("top number") ... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 14 |
Symptoms of heart failure are traditionally divided into left-sided and right-sided because the left and right ventricles supply different parts of the circulation. In biventricular heart failure, both sides of the heart are affected. Left-sided heart failure is the more common. | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 15 |
The left side of the heart takes oxygen-rich blood from the lungs and pumps it to the rest of the circulatory system in the body (except for the pulmonary circulation). Failure of the left side of the heart causes blood to back up into the lungs, causing breathing difficulties and fatigue due to an insufficient supply ... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 17 |
. Rales or crackles are heard initially in the lung bases and when severe in all lung fields indicate the development of pulmonary edema (fluid in the alveoli). Cyanosis, indicates deficiency of oxygen in the blood, is a late sign of extremely severe pulmonary edema. | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 18 |
Reverse insufficiency of the left ventricle causes congestion in the blood vessels of the lungs so that symptoms are predominantly respiratory. Reverse insufficiency can be divided into the failure of the left atrium, the left ventricle, or both within the left circuit. Patients will experience shortness of breath (dys... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 20 |
. Increasing breathlessness while lying down, called orthopnea, also occurs. It can be measured by the number of pillows required to lie comfortably, with extreme cases of orthopnea forcing the patient to sleep sitting up. Another symptom of heart failure is paroxysmal nocturnal dyspnea: a sudden nocturnal attack of se... | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 21 |
. There may be "cardiac asthma" or wheezing. Impaired left ventricular forward function can lead to symptoms of poor systemic perfusion such as dizziness, confusion, and cool extremities at rest. Loss of consciousness may also occur due to loss of blood supply to the brain. | Heart failure | Cardiovascular system | main | wikipedia | https://en.wikipedia.org/wiki/Heart_failure | 22 |
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