It's the most common cause of vascular disease. It's not known how atherosclerosis starts or what causes it. It's a slow, ongoing disease that gets worse over time. It may start as early as childhood. But the disease can also get worse quickly. It causes the buildup of fatty deposits along the innermost layer of the arteries. This thickening narrows the arteries. It can lessen or fully block the flow of blood to organs and other body tissues. Blood clots. A blood vessel may be blocked by an embolus.
This is a tiny mass of debris that moves through the bloodstream. Or it may be blocked by a thrombus. This is a blood clot. In general, inflammation of blood vessels is referred to as vasculitis. This includes a range of disorders. Inflammation may lead to narrowing and blockage of blood vessels. Injury of the blood vessels may lead to inflammation or infection. This can damage the blood vessels and lead to narrowing and blockage.
The functions of the blood vessels include supplying all organs and tissues of the body with oxygen and nutrients. They include removing waste products, fluid balance, and other functions. Because of all these functions, conditions that affect the vascular system may affect the part s of the body supplied by a certain vascular network.
Coronary artery disease. This can cause heart attack or angina chest pain. Cerebrovascular disease. This can cause stroke or transient ischemic attack TIA. TIA is a short-term loss of blood flow to an area of the brain. It usually last less than 5 minutes but not longer than 24 hours, with complete recovery. Peripheral arterial disease. This may cause claudication. This is pain in the thigh, calf, or buttocks that occurs when walking. It can also cause critical limb ischemia. This is lack of blood supply and oxygen to the limb or leg at rest.
Vascular disease of the great vessels. This can cause an aortic aneurysm. This is a bulging, weakened area in the wall of a blood vessel due to an abnormal widening or ballooning. It can also cause coarctation of the aorta. This is narrowing of the aorta, the largest artery in the body.
It can also cause Takayasu arteritis. This is a rare inflammatory disease that affects the aorta and its branches. The first is the systemic circulatory system. This is the main blood circulatory system that transports blood to the organs, tissues, and cells throughout the body. The second is the pulmonary circulatory system. This circulatory system moves blood between the heart and lungs. It is where oxygen enters the blood and carbon dioxide leaves the blood. Valves control the flow of blood within the different chambers.
Blood follows the following path through the heart:. The heart pumps blood through closed vessels to every tissue within the body. The blood itself then delivers nutrients and oxygen to all cells in the body. Without blood, the cells and tissues would not function at their total capacity and would begin to malfunction and die. The cardiac cycle consists of two phases.
The first phase is diastole, in which the ventricles fill with blood. It begins when the aortic or pulmonary valve closes and ends when the mitral or tricuspid valve closes.
During diastole, blood vessels return blood to the heart in preparation for the next contraction of the ventricles. The second phase is systole, in which the ventricles contract and eject blood. It begins when the mitral or tricuspid valve closes and ends when the aortic or pulmonary valve closes. The pressure inside the ventricles becomes greater than the pressure inside adjacent blood vessels, thereby forcing the blood from the ventricles to the vessels.
Cardiovascular diseases can be severe and potentially life threatening. Understanding conditions that can affect the cardiovascular system may help people seek appropriate and timely medical advice. A heart attack happens when a part of the heart muscle does not receive enough blood. This can occur due to a blockage, a tear in an artery around the heart, or if the heart requires more oxygen than is available. Symptoms of a heart attack include :.
People who have had a heart attack can lower their chances of future cardiovascular problems by engaging in the following:. A stroke is a medical condition in which the blood supply to a part of the brain becomes cut off. This lack of blood supply triggers the death of brain cells. There are two types of stroke. Ischemic stroke occurs as a result of a blood clot blocking blood flow to the brain. Hemorrhagic stroke occurs as a result of a bleed in or around the brain. The treatment for stroke will depend on the type.
A person who experiences ischemic stroke may receive medications to help break up the blood clot and restore blood flow to their brain. It is in the microscopic capillaries that blood performs its ultimate transport function. Nutrients and other essential materials pass from capillary blood into fluids surrounding the cells as waste products are removed.
Numerous control mechanisms help to regulate and integrate the diverse functions and component parts of the cardiovascular system in order to supply blood to specific body areas according to need.
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