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Definition of elastic and muscular arteries vein, capillary, Velocity of blood flow, Varicose Veins and Arteriosclerosis
Elastic artery: Elastic arteries are directly after the heart. They have a special elasticity, because of the pulse of the heart, there is a lot of pressure exerted on the artery and thus, the arteries have to be elastic. The diameter of an elastic artery differs from 0.4 cm to 2.5 cm. They have very thick walls (1-2mm) to tolerate the pressure, which comes from the heart. The pulmonary arteries, the aorta and its branches add up to the body’s elastic artery system.
Muscular artery: Muscular arteries or distributive arteries are found before organs and after elastic arteries. Unlike the elastic artery, they are not this elastic, because the pressure after the elastic arteries stays more or less constantly, and their diameter ranges from 0.1mm to 10mm. They draw the blood from elastic arteries to the organs and capillaries.
Vein: Veins appear directly after organs and draw the blood to the heart. The pressure situation in veins is low and in order to bring the blood to the heart, they have a special pressure mechanism. Moreover, they possess valves, which prevent blood from flowing backwards. The diameter of a vein ranges from 0.5 cm to 3 cm.
Capillary: Capillaries are found in organs. They are extremely small (5-10 μm) and enable an exchange of water, oxygen, carbon dioxide, nutrients and many other waste chemical substances with the blood and the surrounding tissues.
Change in pressure and velocity of blood flow and during certain situations
Velocity of blood flow: At the beginning, in the left atrium and ventricle, the velocity is at its peak. As the blood is catapulted into the aorta, the velocity remains high, but decreases along the arteries. By reaching the capillaries, the velocity of blood decreases to a minimum. As soon as the blood flows into the veins, its velocity will increase, since the veins have a special pressure mechanism. Otherwise, blood could not be able to reach the heart without this mechanism. The velocity of the blood flow will decrease after it has passed the right atrium and ventricle and approaches the lung capillaries, where again, the velocity of blood flow will decrease to nearly nothing. As soon as it enters the pulmonary veins, the blood flow will increase in speed (velocity).
Pressure situation of the blood flow: The pressure is directly linked to the velocity of blood flow. The pressure is extremely high at the beginning of the heart (left atrium and ventricle). The reason is that blood has to travel a long distance (to all of the organs and capillaries), which requires a high “starting energy”. During the capillaries, the pressure will fall to a minimum and only increase slightly through the veins. Unlike the left atrium and ventricle, the pressure situation in the right atrium and ventricle is relatively low; as the blood has to be pumped only to the pulmonary arteries (distance is very short).
Disorders of the circulation system (causes, symptoms, treatment and prevention)
Varicose veins have lost their ability to prevent backflow, because they are very dilated and congested.
-aching legs (especially worse at night and after exercise)
-ankle swelling, especially in the evening
-appearance of spider veins in the affected leg
-skin near the affected vein(s) are coloured brownish-blue
-minor injuries in the affected area may take longer to heal or bleed longer than normal
Causes: Causes can be heredity (people’s valves are not working properly or are completely dysfunctional or they are born with too few valves), age, pregnancy, obesity, prolonged standing, leg injury and abdominal straining.
Treatment: There are many possible treatments an individual can do at home on its own.
- elevating the leg as much as possible
- wearing compression stockings (especially effective in the mornings)
- losing weight with a diet which is high in fibres and low in fat
- avoiding alcohol, since it can cause a dilation in the veins
- do not cross the legs while sitting
- walking, because it forces the blood out of the deeper vein system (although there is no scientific evidence)
Prevention: There is no real prevention to varicose veins, but people can do some things to alleviate the agony or to increase the chance that it happens at all:
- watching your weight
- lose weight with a diet which is high in fibres and low in fat (salt can also help)
- changing sitting and standing position regularly (especially important if you work in an office)
- elevating your legs for certain periods of time daily (like elevating your leg every day for thirty minutes)
Arteriosclerosis: The process of hardening (and loss of elasticity) in large or medium arteries.
Example of (coronary) atherosclerosis(fats and cholesterols are deposited in arteries, forcing them to become stiff and to become clogged.)
-pain in the fest: It feels like squeezing or crushing the breastbone or the sternum. This is due to the degeneration of the heart muscles due to insufficient oxygen.
-feeling weak or fatigued: Due to the oxygen deficiency in the body and especially in the brain.
-dyspnea (shortness of breath)
-irregular heartbeats: Arteries and in particular the coronary artery can be blocked completely. This can cut off the blood supply from the arteries to the heart, what results into a diminished function of heart muscles and causing irregular (or arrhythmic heartbeats)
-Nausea and Sweating (both rather uncommon)
-avoid high cholesterol food and adapt a low-salt, low-fat diet
-exercise to maintain a healthy weight
-never start smoking or quit smoking
-lose excessive weight
-lowering the intake of cholesterol and fats