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- Skeletal system - Joints - Muscles - Heart - Blood vessels - Respiratory system - Digestive system - Endocrine glands - Nervous system - Eye - Ear - Lymphatic system - Female reproductive system Heart The heart (Latin: cor) is a thick, muscular organ with four cavitated parts located in the middle mediastinum. It is a central organ and pump of the cardiovascular system that maintains the unidirectional flow of blood through the circulatory system. The heart is a vital organ meaning a person can not live without it. The heart consists of the right and left side (or right and left pump) and four main parts: right atrium and right ventricle, left atrium and left ventricle. The heart is surrounded by a serous sac called the pericardium. The great vessels originating from the heart provide blood flow throughout the whole body. External heart anatomy The heart has a cone or pyramid shape with its base projected upward, backward, and right. And the apex of the heart is directed forward, downward, and to the left. Approximately two-thirds of the heart is located on the left, while one-third on the right side from the midline of the body. The apex of the heart is typically located deep to the left 5th intercostal space and is formed by the left ventricle. The longitudinal axis of the heart extends from the base to the apex. It goes from the top to the bottom, from right to left, and from back to the front. The heart is slightly rotated around the longitudinal axis to the left. The right side of the heart is located closer to the ventral surface of the body, while the left side - closer to the dorsal surface of the body. The heart weighs around 200 to 400 grams (7 to 14 oz). Each day it beats about 100,000 times and pumps approximately 6 - 7,5 liters (1,6-2 gallons) of blood. The average heart rate is 60 to 90 heartbeats per minute. Externally, the heart has four borders and five surfaces formed by different internal parts. The external surfaces of the heart contain grooves - external sulci. Heart borders The heart has four borders separating the surfaces: - Superior border - formed by the right and left atrium, auricles, and the great vessels; - Right border - formed by the right atrium extending between the superior and inferior vena cava; - Left border - created by the left ventricle and left auricle; - Inferior border - formed by the left and right ventricles. Position of heart The superior border of the heart goes horizontally at the level of the 3rd rib cartilage, and the right one goes archwise down from the 3rd rib cartilage to the 5th rib cartilage. This border is located approximately 1,5 centimeters from the sternum on the right side. The inferior border goes obliquely down from the cartilage of the 5th rib on the right side to the apex of the heart on the left side. The apex of the heart is projected in the fifth intercostal space. It is approximately 1,5 centimeters medially from the left midclavicular line. The left border goes obliquely upwards from the apex to the site where the cartilage of the third rib joins the bony part of the rib. Heart surfaces The heart has five surfaces: - Diaphragmatic surface (inferiorly) - Sternocostal surface (anteriorly) - Right and left pulmonary surfaces (medially and laterally) - Base of heart (posteriorly) Diaphragmatic surface The heart in its anatomical position rests on the diaphragmatic surface, which is a flat surface. It is faced inferiorly and lies on the respiratory diaphragm. This surface is formed by the right ventricle and a small part of the left ventricle separated by the posterior interventricular groove. Sternocostal surface The sternocostal (anterior) surface of the heart is convex. It is directed anteriorly and slightly to the left against the sternum and inner surfaces of the ribs. It consists mainly of the right ventricle, a part of the right atrium, and part of the left ventricle. On the sternocostal surface above the coronary sulcus are located two auricles - right and left. The right one is larger than the left one. Pulmonary surfaces The right and left pulmonary surfaces are broad, rounded, convex, and face the lungs. The left pulmonary surface is formed by the left ventricle and a part of the left atrium. And the right pulmonary surface consists of the right atrium. Base of heart The base of the heart is quadrilateral and oriented posteriorly. It consists of the left atrium, a small portion of the right atrium, and the proximal parts of the great veins (superior vena cava and inferior vena cava, as well as the pulmonary veins). The base of the heart is fixed posteriorly to the pericardial wall, opposite the bodies of the 4th/5th to 8th thoracic vertebrae (5th/6th to 9th when standing). External sulci of heart The internal partitions forming four chambers produce grooves on the external surface called external sulci, including the coronary sulcus and the anterior and posterior interventricular sulci. All of these external sulci are continuous with each other inferiorly, just to the right of the apex. The area on the lower backside of the heart where the coronary sulcus meets the posterior interventricular sulcus is called the cardiac crux or crux of the heart. Coronary sulcus The coronary sulcus is also known as the atrioventricular groove. It is a groove that circles the heart, marking the separation between the atria and the ventricles. It contains the right coronary artery, the small cardiac vein, the coronary sinus, and the circumflex branch of the left coronary artery. Anterior and posterior interventricular sulci The anterior and posterior interventricular sulci go in a vertical direction and mark the separation of both ventricles. The anterior interventricular sulcus is situated on the anterior surface (sternocostal surface). It contains the anterior interventricular artery and the great cardiac vein. The posterior interventricular sulcus is located on the diaphragmatic surface. It contains the posterior interventricular artery and the middle cardiac vein. Anatomical relations of heart Anteriorly to the heart is located the sternum and cartilages of the ribs, and the left lung. Posteriorly organs of the posterior mediastinum are situated, including the esophagus, descending thoracic aorta, azygos vein, hemiazygos vein and thoracic duct, as well as other blood vessels, nerves, and lymph nodes. Below the heart - inferiorly - lies the central tendon of the respiratory diaphragm. Above or superiorly the large blood vessels of the heart and the bifurcation of the main pulmonary trunk are located. The lateral sides of the heart are related to the mediastinal part of the parietal pleura and lungs. Internal heart anatomy Internally, the heart is divided into four chambers: right and left atria (singular: atrium) and right and left ventricles. The chambers are separated by septa containing subdivisions. The interatrial subdivision is the upper part, located between atria. The interventricular subdivision is the lower portion located between the ventricles. But the atrioventricular part is located between the atria and ventricles. The heart consists of two pumps (right and left), each formed by an atrium and a ventricle separated by a valve. The right pump (consisting of right atrium and right ventricle) receives deoxygenated blood and pumps it into the lungs. And the left pump (left atrium and left ventricle) receives oxygenated blood from the lungs and sends it to the body. The atria receive blood, thus, have relatively thin walls, while the ventricles have reasonably thick walls, as they pump blood out of the heart. Right atrium The right atrium of the heart is situated in the superior right corner of the heart above the right ventricle. The systemic circulation ends in the right atrium. The deoxygenated blood enters it through the inferior and superior vena cava and the coronary sinus. Walls of right atrium The right atrium has a cuboid shape. Therefore it has six walls: - Superior - Inferior - Anterior - Posterior - Lateral - Medial Between the medial and posterior walls below the depression known as fossa ovalis is located a small opening called the opening of the coronary sinus. Through this opening, the coronary sinus opens to the right atrium. The coronary sinus collects venous blood from the heart muscle. It is protected by a semicircular fold of the lining membrane, called the valve of the coronary sinus (also known as the Thebesian valve). The superior vena cava opens to the superior wall of the right atrium with an aperture called opening of the superior vena cava. On the inferior wall of the right atrium the right atrioventricular orifice is found. It is an oval opening between the right atrium and the right ventricle. On the anterior wall is placed the right auricle. The primary function of the right auricle is to increase the volume of the right atrium. The muscular layer of the heart creates parallel ridges in the anterior wall and the auricle. They are called the pectineal muscles. On the posterior wall the opening of the inferior vena cava is located where inferior vena cava opens to the right atrium. Along the inferior margin of the opening of the inferior vena cava extends a semilunar valve called the valve of the inferior vena cava. The valve functions in the fetus until birth. It directs blood from the right atrium through the foramen ovale to the left atrium. The enlarged posterior part of the right atrium receiving blood directly from both inferior and superior venae cavae is called the sinus of the venae cavae. On the lateral wall of the right atrium the pectineal muscles are located. The medial wall is formed by the interatrial septum. In the interatrial septum lies an oval fibrous depression called the fossa ovalis covering the foramen ovale during fetal development. Around the fossa ovalis is an oval margin named the annulus ovalis or limbus of the fossa ovalis. Small openings for the smallest cardiac veins are also located on the medial wall of the right atrium. Right ventricle The right ventricle is one of the heart chambers located in the inferior right portion of the heart under the right atrium and opposite to the left ventricle. The right ventricle contains deoxygenated blood. The primary function of the right ventricle is to pump blood up through the pulmonary valve and trunk into the lungs, thus providing pulmonary circulation. The right ventricle has a pyramidal shape with the base directed upwards and the apex - downwards. The medial wall of the right ventricle is formed by the interventricular septum. The inferior wall lies close to the central tendon of the diaphragm. The anterior wall of the right ventricle is directed towards the inner surfaces of the sternum and ribs. The base of the right ventricle contains the right atrioventricular orifice and the opening of the pulmonary trunk. The part of the right ventricle that leads to the opening of the pulmonary trunk is called the infundibulum (or conus arteriosus). It is a conical extension formed from the upper and left angles of the right ventricle. The inner surface of the right ventricle is smooth only in the infundibulum. Elsewhere the muscular layer of the heart creates papillary muscles and irregular muscular columns called trabeculae carneae. Right atrioventricular orifice and tricuspid valve Venous blood from the right atrium enters the right ventricle through the right atrioventricular orifice. Around the right atrioventricular orifice is the tricuspid valve. The tricuspid valve has three leaflets - the anterior, posterior, and septal leaflets. Around the orifice is a fibrous ring called the fibrous annulus. The right atrioventricular valve opens during atrial systole. It allows deoxygenated blood from the right atrium to flow into the right ventricle. The valve closes during the ventricular systole. The primary function of the tricuspid valve is to prevent the backflow of the blood from the ventricles into the atria. There are three papillary muscles in the right ventricle. Leaflets are connected with chordae tendineae. The chordae tendineae arise from one leaflet and insert into two adjacent papillary muscles. The chordae tendineae prevent the valve leaflets from prolapsing into the right atrium. The papillary muscles fix the tricuspid valve, but trabeculae carneae prevents blood swirling. Opening of pulmonary trunk and valve The exit opening from the right ventricle is the opening of the pulmonary trunk. Deoxygenated blood enters the pulmonary trunk through this opening. The trunk divides into two pulmonary arteries - right and left pulmonary arteries. The opening is located behind the left sternocostal joint of the third rib. Around the opening of the pulmonary trunk is the pulmonary valve, which is a semilunar valve. It has three semilunar cusps: anterior left and right. It is attached to a fibrous annulus located around the opening. During ventricular systole, the pressure in the ventricle increases as the walls shrink. Valves are pressed against the inner surface of the pulmonary trunk, and the blood flows through it. As the pressure in the right ventricle decreases, the valve closes. Left atrium The left atrium is located in the superior left corner, above the left ventricle, and opposite to the right atrium. The pulmonary circulation ends in the left atrium, as oxygenated blood from the lungs enter it through the pulmonary veins. The left atrium has a cuboid shape. It is thicker but smaller in volume than the right atrium. The medial wall of the left atrium is formed by the interatrial septum, which separates the left and right atria. On the anterior wall of the left atrium lies the left auricle, a flap of the heart wall. The left auricle has an irregular shape with many tiny ridges created by the pectinate muscles. The primary function of the left auricle is to increase the volume of the left atrium. Elsewhere, the inner surface of the left atrium is smooth. Openings of left atrium There are five openings found in the walls of the left atrium. These include four openings for the pulmonary veins and one opening called left atrioventricular orifice. The four openings for the pulmonary veins are located on the superior and posterior walls of the left atrium. The pulmonary veins carry oxygenated blood from the lungs to the left atrium. The left atrioventricular orifice is found on the inferior wall of the left atrium. It carries oxygenated blood to the left ventricle. Left ventricle The left ventricle is one of the heart chambers located in the lower-left portion of the heart below the left atrium, opposite to the right ventricle. The primary function of the left ventricle is to pump blood into the aorta, providing systemic circulation. The left ventricle has a cone shape with a base directed upward, while the apex is directed inferiorly. There are two openings found on the base of the left ventricle - the left atrioventricular orifice and aortic orifice. There are fibrous rings and valves around both openings. The anterosuperior portion of the left ventricle below the aortic orifice is called the aortic vestibule. The inner surface of the heart is smooth at the aortic vestibule. Elsewhere the inner surface is covered by papillary muscles and trabeculae carneae. Left atrioventricular orifice and mitral valve Around the left atrioventricular orifice is the left atrioventricular valve (also called the mitral valve, bicuspid valve). The mitral valve has two cusps - the anterior and posterior. Between both cusps are smaller ones called the commissural cusps. The opening of the mitral valve is surrounded by a fibrous ring called the mitral annulus. The chordae tendineae are inelastic tendons attached to the cusps and the papillary muscles within the left ventricle. The chordae tendineae prevent the valve leaflets from prolapsing into the left atrium. The left atrioventricular valve opens during atrial systole, allowing arterial blood from the left atrium to enter the left ventricle. The valve closes during the ventricular systole. Aortic orifice and aortic valve The aortic orifice is guarded by the semilunar aortic valve. It is made of three cusps - left, right and posterior. The aortic orifice is surrounded by a fibrous ring called the annulus fibrosus, which fixes the aortic valve. The aortic orifice is located in the midline behind the sternum at the 3rd intercostal level. Heart sound locations and heart auscultation The closing of each heart valve can be auscultated at a specific place on the anterior wall of the chest. - The right atrioventricular or tricuspid valve can be auscultated in the fifth intercostal space on the right side of the sternum or the xiphoid process of the sternum. - The sound of the left atrioventricular or mitral valve can also be best heard in the fifth intercostal space on the left side, approximately 1,5 centimeters medial from the left midclavicular line. - The aortic valve can be found in the second intercostal space on the right side of the sternum. - The pulmonary valve can also be heard in the second intercostal space but on the left side of the sternum. Pulmonary and systemic circulation The systemic circulation starts in the left ventricle containing oxygenated blood (rich in oxygen). Through the aorta and its branches, blood spreads through the body and reaches all organs. Tissue receives oxygen, and the oxygenated blood becomes deoxygenated. It is being accomplished by the arterioles, pre-capillaries, capillaries, post-capillaries, and finally by the venules going back to the heart. Deoxygenated blood reaches the heart through the superior and inferior venae cavae and coronary sinus, flowing into the right atrium, where ends the systemic circulation. The pulmonary circulation starts with the right ventricle containing deoxygenated blood. Blood reaches the lungs through the pulmonary trunk and right and left pulmonary arteries. Arteries form a network of capillaries in the lungs and in the alveolar walls where happens the gas exchange. Deoxygenated blood becomes oxygenated and reaches the left atrium of the heart through the pulmonary veins. The pulmonary circulation ends in the left atria of the heart. Layers of heart wall The wall of the heart is formed by three layers: - Endocardium - the inner layer; - Myocardium - the middle layer; - Epicardium - the outer layer. The heart with all three layers is covered by the pericardium. Endocardium The endocardium is the inner layer of. the heart wall, and it lines all the internal surfaces of the heart cavities. It covers the pectinate and papillary muscles, trabeculae carneae, valves, and chordae tendineae. The structure of the endocardium is similar throughout the heart. However, in the left atrium and ventricle, the endocardium is thicker than in the right atrium and ventricle. And the atrial endocardium is more prominent than the ventricular endocardium. Part of the endocardium covering the chordae tendinae is very thin. All of the heart valves are derived from the endocardium, including: - Valve of the inferior vena cava and valve of the coronary sinus in the right atrium - Right atrioventricular (three cusps) and pulmonary valves in the right ventricle - Left atrioventricular (two cusps) and aortic valves in the left ventricle. At the openings of the arteries and veins, the endocardium passes into the walls of blood vessels. Myocardium The myocardium is a thick muscular layer between the endocardium and epicardium. It is formed by cardiac muscle fibers, also known as cardiomyocytes. The primary function of the myocardium is to contract and pump blood out of the heart to provide organs with blood. Cardiac muscles are characterized by rapid contractions that can not be controlled. The myocardial layer is different in the atria and ventricles. In the atria, the myocardium has two layers: an outer circular layer that is common in both atria, and an inner longitudinal layer that is separate in each atrium. The longitudinal layer is formed by pectinate muscles. In the ventricles, the myocardium is formed by three layers: outer and inner layers that are longitudinal and are common in both ventricles, and a middle layer that is circular and separate in each ventricle. In the heart ventricles, the muscles of the inner layer form the papillary muscles and the trabeculae carneae. The outer longitudinal layer at the apex of the heart creates the vortex of the heart - the swirling arrangement of cardiac muscular fibers at the apex of the heart. At the mentioned site, the outer longitudinal layer transitions into the inner longitudinal layer. It happens vice versa as the inner longitudinal layer transitions into the outer longitudinal layer. Epicardium The epicardium is also called the visceral or inner layer of the serous pericardium. It is the outer serous layer of the heart. It is a thin, transparent layer composed of loose connective tissue, elastic fibers, and adipose tissue. The epicardium covers not only the heart but also the beginnings of the large vessels - the ascending aorta, pulmonary trunk, superior vena cava, inferior vena cava, as well as the pulmonary veins before they return to the heart. From these blood vessels, the epicardium further continues as the parietal layer of the serous pericardium. The epicardium protects the inner heart layers. It participates in the production of the pericardial fluid. Pericardium The heart is surrounded by a closed fibrous sac called the pericardium. The pericardium separates the heart from the surrounding organs. The pericardium contains two layers - an outer or fibrous and an inner or serous layer. Fibrous pericardium The outer or the fibrous layer of the pericardium forms a closed sac around the heart and separates the heart from the surrounding organs. It fuses with the respiratory diaphragm and pleura. The anterior surface of the pericardium connects with the inner surface of the sternum and ribs. The inferior surface of the pericardium fuses with the central tendon of the diaphragm and the anterior part of the muscular part of the diaphragm. The lateral surfaces fuse with the mediastinal pleura. Serous pericardium The serous layer of the pericardium has two lamina - the visceral and parietal lamina. The visceral lamina of the serous pericardium is also known as the epicardium. It covers the outer surface of the myocardium, and at the large blood vessels of the heart, it continues as the parietal lamina. The parietal lamina covers the heart and fuses together with the fibrous pericardium. Pericardial cavity The space between the parietal and visceral laminae of the serous pericardium is called the pericardial cavity. It contains a small amount of serous fluid (pericardial fluid) that decreases surface tension. This fluid also lubricates surfaces, allowing free movement of the heart during contractions. The pericardial cavity contains few recesses and two sinuses - transverse pericardial sinus and oblique pericardial sinus. Neurovascular supply of heart Arterial blood supply The arterial blood supply to the heart and heart muscles is provided by the left and right coronary arteries and their branches. Right coronary artery The right coronary artery has the following branches supplying the heart: - Sinoatrial nodal branch - Right marginal branch - Atrioventricular nodal branch - Posterior interventricular branch All mentioned branches except the right marginal artery supply the right atrium and the right ventricle. The right marginal artery supplies the right ventricle and the apex of the heart. The posterior interventricular artery also supplies the interventricular septum. To sum up, the right coronary artery with its branches supply the right atrium and interatrial septum, sinoatrial and atrioventricular nodes, all posterior and partially anterior wall of the right ventricle, posterior third of the interventricular septum, all papillary muscles in the right ventricle, posterior papillary muscle in the left ventricle, a small part of the posterior wall of the left ventricle. Left coronary artery The left coronary artery has the following branches supplying the heart: - Left circumflex branch - Anterior interventricular branch - Left marginal artery To sum up, the left coronary artery perfuses the left atrium and the left ventricle (except a small portion of the posterior wall), part of the anterior wall of the right ventricle, two anterior thirds of the interventricular septum, atrioventricular bundle, and anterior papillary muscles in the left ventricle. Venous drainage The coronary sinus provides venous drainage of the heart with its tributaries. The coronary sinus drains into the right atrium. The main tributary of the coronary sinus is the great cardiac vein arising at the apex of the heart. Besides the great cardiac vein, the middle and small cardiac veins also drain into the coronary sinus. The left marginal vein and left posterior ventricular veins also provide the drainage of the heart. Lymphatic drainage Lymph is drained from the heart tissue via the subendocardial, myocardial lymph nodes and then via subepicardial plexus forming the right and left cardiac collecting trunks. The left trunk drains into the tracheobronchial lymph nodes, and the right trunk - into the brachiocephalic lymph nodes. Innervation The heart is innervated by sympathetic and parasympathetic fibers from the autonomic nervous system, which form the cardiac plexus (contains fibers from both mentioned parts of the autonomic nervous system). Parasympathetic efferent and afferent fibers to this plexus are provided by the vagus nerve (CN X). Impulses of the parasympathetic fibers reduce heart rate and force of myocardial contraction, and also provide vasoconstriction of the coronary arteries. The vagus nerve gives off several cardiac branches such as thoracic cardiac, inferior and superior cervical cardiac branches. The sympathetic efferent innervation is provided by the sympathetic trunk via cardiac nerves of the lower cervical and upper thoracic ganglia. These nerves, in contrast to the parasympathetic nerves, increase heart rate and the force of contraction of the myocardium. The sympathetic afferent innervation is also provided by the lower cervical and upper thoracic ganglia. Sympathetic afferent fibers provide the pain sensation of the heart. Heart functions The heart works as a pump of the circulation system. Its main function is to pump the blood to the systemic and pulmonary circulations providing exchange of deoxygenated and oxygenated blood. Therefore, the heart provides the tissue with oxygen. The heart is the main organ in the circulatory system, and its rhythmic contractions keep an individual alive. - The heart generates blood pressure. - The heart routes the blood as it separates the pulmonary and systemic circulations. - It ensures one-way blood flow because of the valves. - The heart regulates the blood supply as it changes contraction rate and force, responding to metabolic needs. - It provides the cardiac cycle. Cardiac cycle The rhythmic action of the heart and, therefore, the blood flow to the systemic and pulmonary circulations are provided by the sequential contractions of the atria and ventricles. This is called the cardiac cycle. The cycle starts with one heartbeat and ends with another. Each cycle can be divided into two main phases - diastolic and systolic phases. During the diastolic phase, a heart chamber is relaxed, and it fills with blood. During the systolic phase, the heart chambers are in a contracted state and pump the blood further. Each atrium and ventricles go through both mentioned phases. When atria are in the systolic phase, the ventricles are in the diastolic phase and opposite. There are several subphases of the cardiac cycle: - Atrial diastole - Atrial systole - Ventricular diastole - Ventricular systole Atrial diastole During this phase, the atria are relaxed, and the blood passively fills the right atrium via the superior and inferior venae cavae and the left atrium through the pulmonary veins. During this phase, the atrioventricular valves are closed. When the cavity is filled with blood, the pressure in the atria is more significant than it is in the ventricles, that is why the mitral and tricuspid valves open, and the blood flows into the ventricles. Atrial systole During the atrial systole, both atria contract and the blood through the tricuspid and mitral valves flow into the ventricles. In this phase, both ventricles are relaxed and are in a diastolic state. Tricuspid and mitral valves between the atria and ventricles are open. Ventricular diastole During this phase, the atria are in a contracted state. Now, the ventricles of the heart are relaxing from contractions, dilating and filling up with blood. Ventricular systole During this phase, both ventricles are in a contracted state. Blood through the semilunar valves flows into the blood vessels providing systemic and pulmonary circulations (aorta and pulmonary arteries). In this phase, the ventricles empty. Tricuspid and mitral valves during this phase are closed, preventing the blood backflow into the atria. In this phase, the walls of the atria are relaxed and are in a diastolic state.
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Hipertenzija je lijevo srce posuda. MSD priručnik dijagnostike i terapije: Angina pektoris Bogata hrana niske kvalitete. Depresivno emocionalno stanje i stres. Značajke arterijske hipertenzije 3 stupnja Učinite čitanje ovog velikog članka prekretnicom u vašem životu - odustanite od loših navika i promijenite svoj način života. Struktura i funkcija srca Život i zdravlje osobe uvelike ovise o normalnom funkcioniranju njegovog srca. Pumpa krv kroz krvne žile tijela, održavajući vitalnost svih organa i tkiva. Evolucijska struktura ljudskog srca - shema, krugovi cirkulacije krvi, automatizam ciklusa stezanja i opuštanja mišićnih stanica zidova, rad ventila - sve je podložno osnovnoj zadaći uniformne i dovoljne cirkulacije krvi. Struktura ljudskog srca - anatomija Organ kroz koji je tijelo zasićeno kisikom i hranjivim tvarima je anatomska formacija stožastog oblika, smještena u prsima, uglavnom lijevo. Unutar organa, šupljina podijeljena na četiri nejednaka dijela pregradama su dva atrija i dvije komore. Bivši skupljaju krv iz vena koje ulaze u njih, a one ga gurnu u arterije koje iz njih izlaze. Simptomi i liječenje bubrežne hipertenzije Normalno, na desnoj strani srca atriji i ventrikula nalazi se krv koja je siromašna kisikom, au lijevoj je oksigenirana krv. Ima glatku površinu, volumen ml, uključujući dodatno obrazovanje - desno uho. Debljina stijenke mm. U posudama protoka PP: superiorna vena cava, vene srca - kroz koronarne sinuse i rupice malih vena, donja vena cava. Lijevo LP. Ukupni volumen, uključujući i ušku, je ml, a debljina stijenki je mm. LP uzima krv iz četiri plućne vene. Atrija je podijeljena između interatrijalnog septuma WPPkoji u odraslih obično nema otvora. S šupljinama odgovarajućih komora komuniciramo kroz rupe opremljene ventilima. Na desnoj strani - tricuspid tricuspid, na lijevoj - bicuspid mitral. Debljina stijenke do 5 mm. - MSD priručnik dijagnostike i terapije: Angina pektoris - Hipertenzija: uzroci, liječenje, prognoza, faze i rizici - Komplikacije - - Hipertenzija oticanje lica - Posude niskog tlaka su proširene ili sužene - Ozljede - - Značajke arterijske hipertenzije 3 stupnja - Hematom - February - Tretirajte srce - Kako liječiti - Akademik lange hipertenzije Unutarnja površina u gornjem dijelu je glatkija, bliže vrhu stošca ima veliki broj mišićnih vrpci-trabekule. U središnjem dijelu komore nalaze se tri odvojene papilarne papilarne mišiće, koje pomoću tendinoznih žilačnih vlakana drže tricuspidne lišće ventila u savijanju u atrijalnu šupljinu. Akordi također polaze izravno iz sloja mišića zida. U dnu komore nalaze se dvije rupe s ventilima: služi kao izlaz za krv u plućni trup, povezivanje ventrikula s atrijom. Lijevo LV. Ovaj dio srca okružen je najimpresivnijim zidom čija je debljina mm. LV šupljina je također sužena i ima dvije rupe: atrioventrikularan s bikuspidalnim mitralnim ventilom, izlaz u aortu s trikuspidalnom aortom. Mišićni vrpci na vrhu srca i papilarni mišići koji podržavaju mitralni ventil snažniji su od sličnih struktura u gušterači. Ljuska srca Kako bi se zaštitilo i osiguralo kretanje srca u prsnoj šupljini, okruženo je srčanom košuljom - perikardom. Izravno u zidu srca nalaze se tri sloja - epikard, endokard, miokard. Perikard se naziva vrećica srca, labavo je pričvršćena za srce, vanjski list je u dodiru sa susjednim organima, a hipertenzija je lijevo srce posuda je vanjski sloj zida srca - epikard. Modifikacija uobičajenog načina života nužno je uključena u popis aktivnosti liječenja. Sastav - vezivno tkivo. Normalna količina tekućine je normalno prisutna u perikardijalnoj šupljini radi boljeg klizanja srca. Epikard također ima osnovu vezivnog tkiva, akumulacije masnoće se promatraju u apeks području i duž koronarnih brazdi gdje se nalaze posude. Na drugim mjestima epikard je čvrsto povezan s mišićnim vlaknima osnovnog sloja. Angina pektoris Miokard je debljina glavnog zida, osobito u najopterećenijem području - regiji lijeve klijetke. Mišićna vlakna smještena u nekoliko slojeva idu uzdužno i u krug, osiguravajući ujednačenu kontrakciju. Miokardij tvori trabekule u vrhu i ventrikula i papilarnih mišića, od kojih se produžuju tendinozni akordi do letaka ventila. Mišići atrija i ventrikula odvojeni su gustim vlaknastim slojem, koji također služi kao okvir za atrioventrikularne atrioventrikularne ventile. U gornjem dijelu, nazvanom membranski, njegova osnova je vezivno tkivo. Endokard je list koji pokriva sve unutarnje strukture srca. Troslojna je, jedan od slojeva je u dodiru s krvlju i sličan je strukturi endotelu posuda koje ulaze i dolaze iz srca. OTVORENI STUDIO - Saznajte koliki je vaš krvni tlak! Također u endokardiju postoji vezivno tkivo, kolagenska vlakna, stanice glatkih hipertenzija endometrij. Svi ventili srca formiraju se iz nabora endokardija. Struktura i funkcija ljudskog srca Crpljenje krvi srcem u vaskularno dno osigurano je osobitostima njegove strukture: mišić srca je sposoban za automatsko stezanje, sustav provodljivosti osigurava postojanost ciklusa uzbude i opuštanja. Kako je ciklus srca Sastoji hipertenzija je lijevo srce posuda od tri uzastopne faze: ukupne dijastole relaksacijesistole kontrakcije atrija, ventrikularne sistole. Ukupna dijastola - razdoblje fiziološke stanke u radu srca. U ovom trenutku, srčani mišić je opušten, a ventili između ventrikula i atrija su otvoreni. Iz venskih žila krv slobodno ispunjava šupljine srca. Ventili plućne arterije i aorte su zatvoreni. Atrijska sistola nastaje kada se pejsmejker automatski pobuđuje u čvorištu atrijalnog sinusa. Na kraju ove faze, ventili između ventrikula i atrija se zatvaraju. Ventrikularna sistola odvija se u dvije faze - izometrijska napetost i izbacivanje krvi u krvne žile. Razdoblje napetosti započinje asinhronom kontrakcijom mišićnih vlakana komora do potpunog zatvaranja mitralnih i tricuspidnih ventila. Zatim, u izoliranim komorama, napetost počinje rasti, a pritisak se povećava. Kada postane viša nego u arterijskim žilama, pokreće se razdoblje izgnanstva - otvaraju se ventili za otpuštanje krvi u arterije. Tada se intenzivno smanjuju mišićna vlakna zidova komora. Tada se smanjuje tlak u komorama, zatvaraju se arterijski ventili, što odgovara nastanku dijastole. U vrijeme potpunog opuštanja otvaraju se atrioventrikularni ventili. Provodni sustav, njegova struktura i rad srca Omogućuje kontrakciju miokarda provodnog sustava srca. Njegova glavna značajka je automatizam ćelija. Oni su sposobni samo-uzbuđeni u određenom ritmu, ovisno o električnim procesima koji prate srčanu aktivnost. U sastavu hipertenzija je lijevo srce posuda sustava su međusobno povezani sinusni i atrioventrikularni čvorovi, temeljni snop i grananje njegovih, purkinjskih vlakana. Sinusni čvor Obično generira početni impuls. Nalazi se u ustima obje šuplje vene. Od njega, ekscitacija ide na atrije i prenosi se na atrioventrikularni AV čvor. Atrioventrikularni čvor širi impuls na ventrikule. Snop Njegova - vodljivi "most", smješten u interventrikularnom septumu, ondje je podijeljen na desne i lijeve noge, prenoseći pobudu komora. Purkinje vlakna su završni dio provodnog sustava. Nalaze se na endokardiju i izravno su u kontaktu s miokardom, što uzrokuje njegovo stiskanje. Struktura ljudskog srca: shema, krugovi cirkulacije krvi Zadatak cirkulacijskog sustava, čije je glavno hipertenzija je lijevo srce posuda srce, je isporuka kisika, hranjivih tvari i bioaktivnih sastojaka u tkiva tijela i uklanjanje metaboličkih produkata. U tu svrhu osiguran je poseban mehanizam za sustav - krv se kreće u krugovima cirkulacije - malim i velikim. Mali krug Hipertenzija je lijevo srce posuda desne klijetke u vrijeme sistole, venska krv se gura u plućni trup i ulazi u pluća, gdje su u mikroviselima alveoli zasićeni kisikom i postaju arterijski. Ulijeva se u šupljinu lijevog atrija i ulazi u sustav velikog kruga cirkulacije krvi. Veliki krug Od lijeve klijetke do sistole, arterijska krv kroz aortu, a zatim kroz posude različitih promjera, dolazi do različitih organa, dajući im kisik, prenoseći hranjive i bioaktivne elemente. U malim kapilarama tkiva krv se pretvara u venski, jer je zasićena metaboličkim proizvodima i ugljičnim dioksidom. Prema sustavu vene, on hipertenzija je lijevo srce posuda u srce, ispunjavajući njegove prave dijelove. Mjesto liječenja hipertenzije - Razlozi Priroda je mnogo radila, stvarajući tako savršen mehanizam, koji mu daje dugogodišnju sigurnost. Stoga je vrijedno liječiti ga pažljivo, kako se ne bi stvarali ganglioplegic hipertenzija s cirkulacijom krvi i vlastitim zdravljem. Struktura srca Srce je šuplji četverokomorni mišićni organ. Veličina srca približno odgovara veličini šake. Prosječna masa srca je g. Vanjska ljuska srca je perikard. Sastoji se od dva lista: jedan oblikuje perikardijalnu vrećicu, a drugi - vanjski omotač srca - epikard. Između perikarda i epikardija nalazi se šupljina ispunjena tekućinom koja smanjuje trenje dok se srce skuplja. Srednji omotač srca je miokard. Sastoji se od trakastog mišićnog tkiva posebne strukture tkiva srčanog mišića. U njemu su susjedna mišićna vlakna međusobno povezana citoplazmatskim mostovima. Međustanične veze ne ometaju pobuđivanje, tako da se srčani mišić može brzo smanjiti.