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Arteriovenous (other)
Arteriovenous refers to relations between arteries and veins, such as: *Arteriovenous malformation *Arteriovenous fistula *Arteriovenous oxygen difference The arteriovenous oxygen difference, or a-vO2 diff, is the difference in the oxygen content of the blood between the arterial blood and the venous blood. It is an indication of how much oxygen is removed from the blood in capillaries as the blood ... * Arteriovenous anastomosis {{dab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artery
An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in the pulmonary circulation that carry blood to the lungs for oxygenation, and the umbilical arteries in the fetal circulation that carry deoxygenated blood to the placenta. It consists of a multi-layered artery wall wrapped into a tube-shaped channel. Arteries contrast with veins, which carry deoxygenated blood back towards the heart; or in the pulmonary and fetal circulations carry oxygenated blood to the lungs and fetus respectively. Structure The anatomy of arteries can be separated into gross anatomy, at the macroscopic scale, macroscopic level, and histology, microanatomy, which must be studied with a microscope. The arterial system of the human body is divided into systemic circulation, systemic arteries, carrying blood from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vein
Veins () are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and fetal circulations which carry oxygenated blood to the heart. In the systemic circulation, arteries carry oxygenated blood away from the heart, and veins return deoxygenated blood to the heart, in the deep veins. There are three sizes of veins: large, medium, and small. Smaller veins are called venules, and the smallest the post-capillary venules are microscopic that make up the veins of the microcirculation. Veins are often closer to the skin than arteries. Veins have less smooth muscle and connective tissue and wider internal diameters than arteries. Because of their thinner walls and wider lumens they are able to expand and hold more blood. This greater capacity gives them the term of ''capacitance vessels''. At any time, nearly 70% o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arteriovenous Malformation
An arteriovenous malformation (AVM) is an abnormal connection between arteries and veins, bypassing the capillary system. Usually congenital, this vascular anomaly is widely known because of its occurrence in the central nervous system (usually as a cerebral AVM), but can appear anywhere in the body. The symptoms of AVMs can range from none at all to intense pain or bleeding, and they can lead to other serious medical problems. Signs and symptoms Symptoms of AVMs vary according to their location. Most neurological AVMs produce few to no symptoms. Often the malformation is discovered as part of an autopsy or during treatment of an unrelated disorder (an " incidental finding"); in rare cases, its expansion or a micro-bleed from an AVM in the brain can cause epilepsy, neurological deficit, or pain. The most general symptoms of a cerebral AVM include headaches and epileptic seizures, with more specific symptoms that normally depend on its location and the individual, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arteriovenous Fistula
An arteriovenous fistula is an abnormal connection or passageway between an artery and a vein. It may be congenital, surgically created for hemodialysis treatments, or acquired due to pathologic process, such as trauma or erosion of an arterial aneurysm. Clinical features Pathological Hereditary hemorrhagic telangiectasia is a condition where there is direct connection between arterioles and venules without intervening capillary beds, at the mucocutaneous region and internal bodily organs. Those who are affected by this conditions usually do not experience any symptoms. Difficulty in breathing is the most common symptom for those who experience symptoms. Just like berry aneurysm, a cerebral arteriovenous malformation can rupture causing subarachnoid hemorrhage. Causes The cause of this condition include * Congenital (developmental defect) * Rupture of arterial aneurysm into an adjacent vein * Penetrating injuries * Inflammatory necrosis of adjacent vessels * Complication of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arteriovenous Oxygen Difference
The arteriovenous oxygen difference, or a-vO2 diff, is the difference in the oxygen content of the blood between the arterial blood and the venous blood. It is an indication of how much oxygen is removed from the blood in capillaries as the blood circulates in the body. The a-vO2 diff and cardiac output are the main factors that allow variation in the body's total oxygen consumption, and are important in measuring VO2. The a-vO2 diff is usually measured in millilitres of oxygen per 100 millilitres of blood (mL/100 mL).Malpeli, ''Physical Education'', Chapter 4: Acute Responses to Exercise, p. 106. Measurement The arteriovenous oxygen difference is usually taken by comparing the difference in the oxygen concentration of oxygenated blood in the femoral, brachial, or radial artery and the oxygen concentration in the deoxygenated blood from the mixed supply found in the pulmonary artery (as an indicator of the typical mixed venous supply). Put in simple terms: :''a''-''v''O2 dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
