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Pericardial Heart Valves
The pericardial heart valve was invented by Marian Ionescu, a British surgeon working at the General Infirmary in Leeds, England. He created this artificial bioprosthetic heart valve as a three-cusp structure made of chemically treated bovine pericardium attached to a Dacron cloth-covered titanium frame.Ionescu M I, Tandon A P, Silverton N P, et al. "Long-term durability of the pericardial valve". In: Bodnar E, Yacoub M (Eds) ''Biologic and Bioprosthetic Valves. Proceedings of the Third International Symposium''Yorke Medical Books (1986) New York, pages 165–176 The Realisation of a concept The experimental and in vitro testing of this novel device took place in 1970, and in March 1971, Ionescu began, for the first time, the implantation of the pericardial valve in all three cardiac positions in humans. Between 1971 and 1976 the valves had been made in Ionescu's own hospital laboratory. Throughout these five years of usage in 212 patients the performance of the pericardial valve w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marian Ionescu
Marian Ion Ionescu (born 21 August 1929 in Târgoviște) is a Romanian-born British cardiac surgeon. His interest in heart surgery covered several aspects of this specialty. He was an inventor of surgical devices, mostly artificial heart valves, a scientist in the broad term and a medical educator. Medicine Marian Ionescu's entire medical career was dominated by scientific curiosity and a persistent desire and ability to make progress by creating change, by discovering the unknown, by improving the known and by inventing what he thought would be useful. In 1959 in Cleveland, at Dr Kolff's impulse, he created the first 'single leaflet aortic valve' out of polyurethane. This device never went beyond the experimental stage due to clot formation. During 1961 and 1962 in Romania, he conducted, with his team, extensive experimental and clinical work on the physiology of organisms under deep hypothermia, with the aid of extracorporeal circulation, in animals and in man. The body tem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiologist
Cardiology () is a branch of medicine that deals with disorders of the heart and the cardiovascular system. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians who specialize in this field of medicine are called cardiologists, a specialty of internal medicine. Pediatric cardiologists are pediatricians who specialize in cardiology. Physicians who specialize in cardiac surgery are called cardiothoracic surgeons or cardiac surgeons, a specialty of general surgery. Specializations All cardiologists study the disorders of the heart, but the study of adult and child heart disorders each require different training pathways. Therefore, an adult cardiologist (often simply called "cardiologist") is inadequately trained to take care of children, and pediatric cardiologists are not trained to treat adult heart disease. Surgical aspects are not included in car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surgeon
In modern medicine, a surgeon is a medical professional who performs surgery. Although there are different traditions in different times and places, a modern surgeon usually is also a licensed physician or received the same medical training as physicians before specializing in surgery. There are also surgeons in podiatry, dentistry, and veterinary medicine. It is estimated that surgeons perform over 300 million surgical procedures globally each year. History The first person to document a surgery was the 6th century BC Indian physician-surgeon, Sushruta. He specialized in cosmetic plastic surgery and even documented an open rhinoplasty procedure.Ira D. Papel, John Frodel, ''Facial Plastic and Reconstructive Surgery'' His magnum opus ''Suśruta-saṃhitā'' is one of the most important surviving ancient treatises on medicine and is considered a foundational text of both Ayurveda and surgery. The treatise addresses all aspects of general medicine, but the translator G. D. Si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diastole
Diastole ( ) is the relaxed phase of the cardiac cycle when the chambers of the heart are re-filling with blood. The contrasting phase is systole when the heart chambers are contracting. Atrial diastole is the relaxing of the atria, and ventricular diastole the relaxing of the ventricles. The term originates from the Greek word (''diastolē''), meaning "dilation", from (''diá'', "apart") + (''stéllein'', "to send"). Role in cardiac cycle A typical heart rate is 75 beats per minute (bpm), which means that the cardiac cycle that produces one heartbeat, lasts for less than one second. The cycle requires 0.3 sec in ventricular systole (contraction)—pumping blood to all body systems from the two ventricles; and 0.5 sec in diastole (dilation), re-filling the four chambers of the heart, for a total of 0.8 sec to complete the cycle. Early ventricular diastole During early ventricular diastole, pressure in the two ventricles begins to drop from the peak reached during systo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valve Openings
A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fittings, but are usually discussed as a separate category. In an open valve, fluid flows in a direction from higher pressure to lower pressure. The word is derived from the Latin ''valva'', the moving part of a door, in turn from ''volvere'', to turn, roll. The simplest, and very ancient, valve is simply a freely hinged flap which swings down to obstruct fluid (gas or liquid) flow in one direction, but is pushed up by the flow itself when the flow is moving in the opposite direction. This is called a check valve, as it prevents or "checks" the flow in one direction. Modern control valves may regulate pressure or flow downstream and operate on sophisticated automation systems. Valves have many uses, including controlling water for irrigation, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aortic Table
The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes oxygenated blood to all parts of the body through the systemic circulation. Structure Sections In anatomical sources, the aorta is usually divided into sections. One way of classifying a part of the aorta is by anatomical compartment, where the thoracic aorta (or thoracic portion of the aorta) runs from the heart to the diaphragm. The aorta then continues downward as the abdominal aorta (or abdominal portion of the aorta) from the diaphragm to the aortic bifurcation. Another system divides the aorta with respect to its course and the direction of blood flow. In this system, the aorta starts as the ascending aorta, travels superiorly from the heart, and then makes a hairpin turn known as the aortic arch. Following the aortic arch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitral Table
The mitral valve (), also known as the bicuspid valve or left atrioventricular valve, is one of the four heart valves. It has two cusps or flaps and lies between the left atrium and the left ventricle of the heart. The heart valves are all one-way valves allowing blood flow in just one direction. The mitral valve and the tricuspid valve are known as the atrioventricular valves because they lie between the atria and the ventricles. In normal conditions, blood flows through an open mitral valve during diastole with contraction of the left atrium, and the mitral valve closes during systole with contraction of the left ventricle. The valve opens and closes because of pressure differences, opening when there is greater pressure in the left atrium than ventricle and closing when there is greater pressure in the left ventricle than atrium. In abnormal conditions, blood may flow backward through the valve (mitral regurgitation) or the mitral valve may be narrowed ( mitral stenos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leeds General Infirmary
Leeds General Infirmary, also known as the LGI, is a large teaching hospital based in the centre of Leeds, West Yorkshire, England, and is part of the Leeds Teaching Hospitals NHS Trust. Its previous name The General Infirmary at Leeds is still sometimes used. The LGI is a specialist centre for a number of services, including the Major Trauma Centre and hand transplants. It also provides many general acute services like A&E, intensive care and high dependency units, maternity and state-of-the-art operating theatres. Two new hospitals are planned on the site. One will be a maternity unit with capacity to deliver up to 10,500 babies a year. Completion is planned between 2026-2028. It will remove the need to transfer expectant mothers between St James’s Hospital and Leeds General Infirmary. History The first hospital known as Leeds Infirmary was opened in 1771 on what is now the site of the former Yorkshire Bank in Infirmary Street off City Square, Leeds. Notably, the found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricuspid
The tricuspid valve, or right atrioventricular valve, is on the right dorsal side of the mammalian heart, at the superior portion of the right ventricle. The function of the valve is to allow blood to flow from the right atrium to the right ventricle during diastole, and to close to prevent backflow ( regurgitation) from the right ventricle into the right atrium during right ventricular contraction (systole). Structure The tricuspid valve usually has three cusps or leaflets, named the anterior, posterior, and septal cusps. Each leaflet is connected via chordae tendineae to the anterior, posterior, and septal papillary muscles of the right ventricle, respectively. Tricuspid valves may also occur with two or four leaflets; the number may change over a lifetime. Function The tricuspid valve functions as a one-way valve that closes during ventricular systole to prevent regurgitation of blood from the right ventricle back into the right atrium. It opens during ventricular diastole ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitral
The mitral valve (), also known as the bicuspid valve or left atrioventricular valve, is one of the four heart valves. It has two cusps or flaps and lies between the left atrium and the left ventricle of the heart. The heart valves are all one-way valves allowing blood flow in just one direction. The mitral valve and the tricuspid valve are known as the atrioventricular valves because they lie between the atria and the ventricles. In normal conditions, blood flows through an open mitral valve during diastole with contraction of the left atrium, and the mitral valve closes during systole with contraction of the left ventricle. The valve opens and closes because of pressure differences, opening when there is greater pressure in the left atrium than ventricle and closing when there is greater pressure in the left ventricle than atrium. In abnormal conditions, blood may flow backward through the valve ( mitral regurgitation) or the mitral valve may be narrowed (mitral stenosis). Rhe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
