Blood vessels transport blood throughout your body, carrying oxygen, nutrients and waste products to and from your cells. Diseases affecting blood vessels are among the leading causes of death worldwide.
Treatment depends on where the clot is and how long you’ve had symptoms. Doctors may use drugs to break up or dissolve the clot. They may also give you surgery to remove the clot.
Blood vessels transport blood, carrying oxygen and nutrients to other parts of the body and removing wastes from those tissues. The blood vessels of the vascular system, or circulation, are composed of arteries, arterioles and capillaries. Blood vessels have a tube-like shape and are located throughout the body. Some are large enough to be seen, such as a human’s aorta, which runs down the back of the chest and diaphragm into the abdomen and pelvis. Others are small enough to only be seen under the skin, such as a vein.
Arteries have thick muscular walls so that they can resist the high blood pressure ejected from the heart. They also need to adjust their diameter to maintain and control blood flow. They can do this by expanding (dilating) or contracting (constricting).
From the main artery, blood enters smaller distributing arteries that distribute it to sub-regions of the body. Blood then enters capillaries, which form networks around body cells. Capillaries supply nutrients and oxygen to tissue cells while removing carbon dioxide and other wastes from them.
The wall of a blood vessel is composed of three layers called tunics, which are named for the Latin word for garments: from inner to outer they are the tunica intima, tunica media and tunica externa. Blood vessels are lined by the endothelium, a layer of simple squamous epithelial cells and a thin subendothelium of connective tissue. Between these layers are discontinuous elastic laminae and smooth muscle cells.
Blood from the capillaries flows into progressively larger veins, which finally join to form venules. From here, deoxygenated blood is transported back to the heart via a systemic vein called the vena cava, which carries blood from the arms, legs, chest, and abdomen back toward the heart. A blood vessel that transports oxygen to the lungs is the pulmonary vein. The pulmonary vein, like all veins in the body, contains many blood capillaries.
Blood vessels carry oxygen and nutrients to organs and tissues throughout the body. They also transport wastes away from those tissues. Blood vessels vary in size and shape. Some, like arteries, have thicker walls than others, like veins. All blood vessels, however, have a hollow passage through which blood flows called the lumen.
Blood vessels that receive blood from the heart are known as arteries, and those that carry blood back to the heart are called veins. Arteries are larger than veins and have a more pronounced rounded structure with thicker walls made of living cells (including elastic and collagenous fibers). The inner layer of these vessels is called the endothelium, and it is separated from the tough external layers by a basal lamina.
Veins have thinner, less muscular walls than arteries because blood pressure in them is lower. This allows them to dilate (stretch out) and store a larger volume of blood when needed.
The smallest blood vessels, capillaries, form networks around all body cells and tissues. They supply the cells with oxygen, nutrients and other substances; and they take carbon dioxide and other wastes away from the cells. Capillaries also connect the branches of arteries to the branches of veins.
Once the oxygen and other nutrients have diffused from the blood in capillaries to cells in tissue, they are carried back to the lungs for reoxygenation. The deoxygenated blood then flows through a system of veins and into the heart.
Most arteries have three distinct layers that surround the lumen: the tunica externa, tunica media and tunica intima. The outer layer is a substantial sheath of connective tissue that is composed primarily of collagenous and elastic fibers. This sheath blends with the tougher interior of the blood vessel to help hold it in place.
Most arteries have a narrower lumina than do veins. This is because arteries must be able to handle high-pressure blood, and the walls of arteries are made of living tissue that needs nourishment and removes wastes from the cells of the wall. The lumen of veins, on the other hand, is much wider than that of arteries because they do not need to support a large volume of blood under high pressure.
A blood vessel is a microscopic channel through which oxygen and other materials are delivered to cells of a tissue. Its wall consists of a single layer of endothelial cells.
Capillaries connect vessels that carry blood away from the heart (arteries) to those that return it to the heart (veins). The process of blood flow through a capillary is called microcirculation.
Arteries have relatively thick walls to withstand the high pressure of blood ejected with each heartbeat. They also contain a large number of elastic fibers in the tunica intima and tunica media to help them expand and recoil after blood passes through them.
After capillaries fill with oxygenated blood, they develop little pores in the wall of the capillary to allow water and small molecules to pass through them. These pores are called capillary leaks. The permeability of the capillaries allows white blood cells to move into sites of inflammation and fight infection.
There are three types of capillaries: continuous, fenestrated and sinusoid. The last are the least common. Sinusoid capillaries are flat in structure and have incomplete basement membranes, intercellular gaps and clefts along with fenestrations. The larger openings in these capillaries enable the passage of bigger molecules, including plasma proteins and blood cells. They are found in the liver and spleen, bone marrow and lymph nodes as well as many endocrine glands such as the adrenal and pituitary glands.
The venules that are formed after the capillaries become more permeable are known as postcapillary venules. They are the primary source of nutrient and hormone secretion in most organs. They are also the preferred site for the migration of white blood cells to sites of inflammation. Postcapillary venules have a diameter of about 10-30 micrometers and an endothelial lining with associated pericytes.
Postcapillary venules are the next step in the progression of blood vessels. They are the smallest blood vessels in your body and have thin walls. They feed low-oxygen blood from arteries directly into veins, and they may have one-way valves to prevent blood flowing backward. Eventually, the postcapillary venules will unite to form a vein. Your two main veins are the superior vena cava, which brings blood from your head, chest and arms, and the inferior vena cava, which carries blood from your legs, feet and abdomen back to the heart.
The inner lining of all blood vessels is called the endothelium. It is a single layer of cells that lines the inside of all blood vessels and lymphatic vessels and regulates exchanges between the bloodstream and body tissues. This cellular layer also helps to control fluid balance in the body, and it plays a critical role in blood flow, inflammation, clotting and angiogenesis.
The endothelium is one of the largest organs in your body. It is comprised of a layer of flat cells called simple squamous epithelium that covers a basement membrane that is glued to a thin layer of subendothelial connective tissue. Endothelial cells in direct contact with blood are called vascular endothelial cells, and those that come into direct contact with lymph are called lymphatic endothelial cells. Endothelial cells are tightly attached to each other with the help of a protein called the basal lamina, and they are embedded in an extracellular matrix made of fibronectin, vitronectin and collagen.
The endothelial cell lining is extremely resilient. It routinely withstands constant blood flow, pressure and stretch to maintain the tight barrier that partitions tissues from the body’s circulatory system. It is an active endocrine and a regulatory organ that synthesizes, secretes and releases substances that control blood clotting, platelet aggregation, vascular tone, and various other enzymes, peptides and inflammatory mediators.
Endothelial cells are also involved in the regulation of inflammation, angigenesis, hemostasis and hormone trafficking. They are also one of the most important defense mechanisms against thrombosis, which is the formation of blood clots that obstruct blood flow to parts of the body. Blood vessels can prevent clots by producing chemicals like nitric oxide and prostacyclin, which keep the blood fluid and inhibit the formation of clotting proteins.
Blood vessels are a complex network that transports oxygen and nutrients throughout the body to support all of its vital functions. They respond to many internal and external stimuli, including the force of blood against their walls, changes in temperature and medications you may be taking. Blood vessels also change shape to adjust to physical activity, allowing more blood to reach your arms and legs during exercise to help with circulation.
Your blood vessels carry blood with oxygen and nutrients to your body’s organs. When they are healthy, you don’t usually notice them. But vascular disease, which includes blood clots and inflammation, can affect them.
An aneurysm in the aorta, which runs from your heart to your abdomen, can rupture, leading to life-threatening internal bleeding. If it happens, you may feel severe pain in your chest or belly.
The blood vessels bring oxygen and other nutrients to the organs and tissues in your body. They also remove waste products and carbon dioxide. When a disease affects your blood vessels, you may feel pain. If the symptoms are severe, you should seek medical help right away.
Symptoms of blood vessel diseases include pain, swelling and tenderness. The symptoms vary depending on the type of vascular disease you have. For example, symptoms of a blood clot in your veins are different from those of an aneurysm. Some symptoms are easy to identify, such as pain in your legs when you stand or walk. These symptoms are called claudication. Other symptoms are not as obvious, such as a weakness in your legs or arms. These are signs that there is less blood flowing to those parts of your body because of a narrowing or blockage of the blood vessel.
Vasculitis causes swelling of the walls of your blood vessels, which reduces or blocks the flow of blood to the affected areas of your body. These areas can be the brain (cerebral vasospasm) or the coronary arteries in your heart (coronary artery vasospasm). Vasculitis may cause a wide range of symptoms, depending on the area of your body that is affected.
Blood vessels have flaps inside them, called valves, that open when your muscles contract and close when your muscles relax. If these flaps don’t work the way they should, blood can pool in your veins and cause a clot. The symptoms of a blood clot in a vein are: pain or heaviness in your leg, warmth around the leg, swelling and red skin. The symptoms of a blood clot that travels to your lungs (pulmonary embolism) are: chest pain, shortness of breath and a feeling like something is stuck in your throat.
Numbness is a sign that part of the pathway from nerve receptors in the skin to the brain is not working correctly. You can’t feel light touch, pain, or temperature and may have trouble knowing where your body parts are (position sense).
Numbness can result from things like carpal tunnel syndrome, a stroke, or having pressure on nerves in the neck or spinal cord. It can also be a symptom of certain cancers or disorders such as lupus, multiple sclerosis, and diabetes.
Sometimes numbness disappears on its own or gets better with home treatment. If numbness is caused by a condition like diabetes, medication can help to soothe inflamed nerves and reduce symptoms. If you have numbness that doesn’t go away, talk to your doctor about it.
If the numbness is sudden, it could be a sign of a stroke or other medical emergency. People with a stroke often have numbness on one side of their face and body. It is usually followed by slurred speech and weakness on that side of the body. A transient ischemic attack, or mini-stroke, can also cause numbness in the arm or leg.
If you have long-term numbness, it could be a sign of underlying conditions such as diabetes, peripheral neuropathy, or fibromyalgia. These conditions affect the nerves that lead to your feet and hands. Numbness in the legs and feet can start in the toes and move up toward the calf and foot. It can spread to the fingers and hands, as well. People with numbness in their legs and feet can have difficulty walking and driving. They can also lose their balance and fall more easily.
Over half of your body is made up of water, and much of it flows around in your bloodstream. A smaller amount of fluid also flows through a less-known system called the lymphatic system, which is responsible for removing excess fluid from tissues. Swelling — or edema, in medical terms — happens when any region of your body enlarges due to inflammation or fluid buildup. Swelling can affect internal organs, such as the kidneys, liver and heart, or external ones, like your feet or ankles.
Swelling can be a sign of many different blood vessel disorders, from the very mild to the more serious. For example, an aneurysm is a bulge that forms in a weak part of an artery, and can rupture with life-threatening consequences. Vasculitis, an inflammatory condition that damages the walls of blood vessels, can lead to a wide range of symptoms in different parts of your body. It can cause swollen glands, skin rashes and itching, joint pain, fatigue and weakness.
Another type of swelling that occurs when your blood vessels aren’t working properly is hemarthrosis, which is when there is both bleeding and swelling in a joint. It can be caused by a blood clot, or it may occur because of an injury to the blood vessels in your arms or legs.
Swelling in your legs can also be a sign of varicose veins, which happen when the valves in your blood vessels become damaged and stretch outward. These veins become twisted and can be seen under the surface of your skin. If the symptoms are severe, it’s important to see a doctor right away because you might have a more serious condition, such as venous disease or a blood clot, that requires treatment.
The blood vessels carry nutrient-rich oxygenated blood to your organs and tissues and bring waste products away from them. When something goes wrong with your blood vessels, your body’s normal function is disrupted and you may experience symptoms like those listed below.
Skin changes are common signs of blood vessel diseases and disorders. These changes can include yellowish skin and the whites of your eyes, deep orange to brown urine and clay-colored stools. You may also have a blue-tinged or pale complexion and trouble breathing, especially in your extremities. You can also develop vascular malformations such as twisted or enlarged veins (varicose) or abnormal connections between veins and arteries.
If you are light-skinned, you may look rosy or have reddish skin due to the excess amount of oxygen-rich hemoglobin in your blood vessels. You can also have red or purple-colored bruises as a result of the rupture of blood vessels in the skin. The color of your skin can change as a side effect of cancer treatment, or from other conditions like lupus and rheumatoid arthritis.
Fatigue is a common symptom that can be caused by a wide range of health conditions. If you are suffering from fatigue, it is important to seek medical advice as soon as possible. A doctor will examine your symptoms and perform a physical exam to determine the cause of the fatigue. They will ask you questions about your sleep habits and daily activities to help them find the root cause of your problem. They will also likely order blood tests to look for issues such as anemia or thyroid problems.
It is important to note that fatigue is different from drowsiness. Drowsiness is a normal response to tiredness and can be relieved with a nap or good night of sleep. Fatigue, on the other hand, is an unexplained feeling of tiredness that lingers even after you have had rest. This type of fatigue can be a sign of a serious condition, and it is important to get a diagnosis as soon as possible.
Getting enough sleep, eating a healthy diet, and reducing stress can help to alleviate fatigue. Your doctor may also recommend medication to treat an underlying health condition, such as depression or thyroid disorders. In addition, some medications can cause fatigue, so it is important to talk with your healthcare provider before making changes to your treatment plan. You should also avoid stimulants like caffeine, as they can make the fatigue worse. Instead, it is a good idea to try meditation or relaxation techniques to ease the symptoms of fatigue. If these do not work, you should seek medical attention immediately. The longer you wait to get a diagnosis, the more difficult it will be to treat your fatigue.
Blood vessels carry oxygen, nutrients, carbon dioxide and waste products to and from organs and tissues. They have thin walls that let them expand and contract to control blood pressure.
Blood vessels can become damaged in many ways. Treatments include changing your diet, taking medicine and having surgical procedures.
Varicose veins develop when small valves in your veins break down, allowing blood to pool in the veins. These troublesome veins appear dark under the surface of your skin and can cause painful symptoms like fatigue, heaviness, and swelling. Home remedies can help reduce pain and discomfort associated with varicose veins, but they cannot completely cure them. For varicose vein treatment, you need to visit a specialist in the field of vascular medicine.
Varicose vein treatments can include diet and exercise, massage, and herbal supplements. A diet that is rich in fiber and vitamin C can decrease your risk for varicose veins by helping your body to properly circulate blood. Regular exercise, such as walking, is also a great way to improve circulation and reduce the symptoms of varicose veins.
Herbal supplements can also be effective in treating the symptoms of varicose veins, including pain and swelling. However, it is important to talk with your doctor before taking any herbal supplements, as they may have side effects or interact with medications you are already taking.
One of the most popular home remedies for varicose veins is to apply apple cider vinegar on the affected area. This can be done by diluting the vinegar with water and then applying it to the affected area. This should be done every night before dozing and each morning right after waking up. Vinegar has also been shown to reduce high blood pressure, blood clots, and cholesterol levels.
Another home remedy for varicose veins is to use witch hazel. This can be applied directly to the affected area and is available in many forms, including liquid, gel, soap, and topical pads. Witch hazel is an astringent that can shrink enlarged blood vessels and minimize their appearance.
Broken blood vessels are also a common problem that can be treated at home. These red or purple splotches, called telangiectasias, are actually dilated or enlarged blood vessels. Although these do not usually cause any medical problems, some people find them unsightly and want to get rid of them.
While there is no way to eliminate broken blood vessels, you can prevent them from forming in the first place by staying out of the sun and us
The medications used in blood vessels treatment are a group of drugs that help control the narrowing of small blood vessels that can lead to heart disease, and ease pain. They include statins (cholesterol-lowering drugs) that prevent clots from forming inside the arteries and help them work better, angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers that keep blood vessels from constricting and make it easier for the heart to pump blood, and calcium channel blockers that also cause blood vessels to open and improve blood flow. Other medications that may be used to treat chest pain are nitrates, which convert to a gas called nitrous oxide and activate chemicals in the body that help open blood vessels; and beta blockers, which slow the heart rate and decrease blood pressure by blocking nerve impulses that cause your heart to beat faster.
Clot-busting medication, or thrombolytics, is given as a one-off emergency treatment in hospital after a stroke or transient ischaemic attack (TIA). It helps to break down any clots that are stopping blood getting to the brain. These are known as ischemic strokes. It also reduces the risk of a second stroke. It’s often given to people who have had a stroke, but also to those with heart conditions like atrial fibrillation and high blood pressure or diabetes, who are at increased risk of having a clot.
Blood-thinning medications, or anticoagulants, are long-term treatments that reduce the risk of clots in the arteries, which can cause strokes and circulation problems. They do this by preventing your blood from clotting at all or by increasing the speed at which your body dissolves clots. They can be taken with or without food, and there is a slight chance of more serious side effects, such as blood in the wee or poo or severe bruising.
Studies suggest that certain medicines, particularly the sodium glucose cotransporter 2 inhibitor empagliflozin (Empa), can delay the deterioration of blood vessel function and stiffness that occurs with aging in people with Type-2 diabetes. Other medicines that can improve blood vessel health are metformin, which is prescribed to lower blood sugar in diabetics; and aspirin, which limits inflammation.
Office procedures for blood vessel disease can be safer and less invasive than hospital-based treatments. The patient’s comfort, time in the clinic, and return to normal activities are all improved by office-based vascular procedures. For example, sclerotherapy for broken blood vessels (telangectasias) is very well-suited to an office setting because it requires only localized anesthesia or no sedation. In addition, most minimally invasive vascular procedures for peripheral artery disease and dialysis access maintenance have a low complication rate.
Before the procedure, your health care provider will ask questions about your past health and do a physical exam. You may have blood tests or imaging tests. You should tell your provider if you take medicines that affect blood clotting, such as aspirin or ibuprofen. You will also need to stop taking these before the procedure.
A person with a blocked artery can be treated in the office with a procedure called an atherectomy. An atherectomy involves inserting a catheter into the blocked artery and using a tool to remove the plaque buildup, which is known as atherosclerosis. This reduces the blockage and improves blood flow through the artery.
To assess whether you are a candidate for an office-based procedure, your health care provider will listen to your heart with a stethoscope and test your blood for signs of inflammation and blood clots. Other tests may include a stress test with imaging. In a study of patients having peripheral interventions in the office, complications occurred in only 0.8% of cases. Almost all of these complications were related to anesthesia, sedation, or the procedure itself, and none were caused by a problem with the vessel treated.
The blood vessels that carry blood to the organs and tissues of your body provide them with oxygen, nutrients and waste products. These blood vessels have thin walls that allow the passage of the materials into and out of the cells in your body. After the tissues receive the nutrients and wastes, they send the blood back to the heart through a network of veins.
The arteries deliver oxygen, nutrients and other materials to all parts of the body, and the veins carry the blood back to the heart. If these blood vessels are blocked, a disease of the vascular system develops. The symptoms vary depending on the condition. Some examples of vascular diseases are:
Varicose veins, also called spider veins, develop when the valves that keep blood flowing inside the veins break down. Over time, blood pools in the damaged veins and they become enlarged and bulge under your skin. The disorder occurs most frequently in the legs, although it can occur in other areas of the body. The disorder can result from many conditions, including high blood pressure, scleroderma, Raynaud’s disease, venous insufficiency, or injury.
It is important to know that there is nothing you can do to prevent spider veins from developing, but there are ways to reduce their appearance. Using a moisturizer that contains vitamin C can help reduce their appearance. Wearing sunscreen when going outdoors can also help reduce their appearance. Using cold water to wash your face can help as well, because hot water can cause them to enlarge.
A doctor may also treat existing varicose or spider veins by inserting a tube, called a catheter, into the affected vein. Then, they inject a medicine or deliver a device that blocks blood flow to the weakened vein wall. This stops the bulging blood vessel from bleeding.
Blood vessels transport nutrients and wastes throughout the body. Arteries carry oxygen-rich blood away from the heart while veins return deoxygenated blood back toward the heart. Small blood vessels that branch out from arteries are called arterioles. These small vessels eventually merge into capillaries where nutrient and waste exchange occurs.
Arteries carry oxygen-rich blood away from your heart and distribute it throughout the body. They have thick, muscular walls that can handle the high pressure of blood your heart pumps out with each beat. Arteries branch into smaller vessels called arterioles, and these branch into capillaries. Capillaries are narrow-diameter tubes that can fit red blood cells in single file and are the sites where nutrient-rich blood exchanges with tissue cells. These exchanges supply cells with nourishment and remove waste products from tissues. They also transport carbon dioxide back to the blood.
Each artery is made of three layers of tissue called tunics. The inner, tunica intima, is a smooth lining of endothelial cells and a small amount of connective tissue. The tunica media is a layer of loose connective tissue that surrounds a muscular layer and a blood vessel wall. The outer tunica externa is a layer of sclerotic connective tissue that covers the outside of the blood vessel.
Arteries and arterioles have thicker, more muscular walls than veins and capillaries because they must flex to handle surges of blood as your heart pumps out the blood. They also have to adjust their diameter to maintain proper blood pressure and control the flow of blood through them.
Veins have thinner, less muscular walls because they do not have to flex as much and they must deal with low blood pressure. Veins are able to hold larger volumes of blood, about 75% of the total blood volume in your body at any given time. Most veins have valves that open and close to keep blood flowing in one direction.
Veins primarily carry deoxygenated blood toward your heart. Some, such as the pulmonary veins, transport oxygen-rich blood to your lungs. Others, such as the veins in your legs and arms, carry blood to your heart from organs and limbs. Your venous system is the primary route by which your heart transports oxygen-rich blood to the rest of your body. Your venous system also includes a network of smaller veins that transport deoxygenated blood from your extremities to major veins.
Your veins transport deoxygenated blood back towards your heart, whereas your arteries carry oxygen-rich blood away from your body. Veins are closer to your body’s surface and have thinner walls than arteries. They also have valves that prevent the flow of blood in the wrong direction.
Arteries have thicker walls because they deal with a lot of pressure as blood moves away from the heart. They are also located deep inside your muscles, while veins are found in tissues throughout the body.
Veins start out as tiny vessels called venules, which gradually get larger as they draw blood from capillaries. Once they reach a certain size, they become full-size veins that carry blood to the heart. These veins can be found all over the body and help to provide blood with nutrients and remove waste products.
The next type of blood vessel, the capillary, is very small with thin walls. Capillaries form networks in the tissue that allow for the exchange of blood and tissue cells. This is where the oxygen and nutrients that travel from the blood are taken in, while the waste products, like carbon dioxide, are removed.
Both arteries and capillaries have three layers of blood vessels. The inner layer, called the tunica intima, consists of flat cells known as endothelial cells. The middle layer is called the tunica media and is made of elastic fibers and connective tissue. The outer layer is made of a layer of smooth muscle tissue. Smooth muscle tissue contracts and expands, causing changes to the diameter of the blood vessels.
The smallest type of blood vessels, the venules, are very tiny with very thin walls. They are the first place where blood enters a capillary network. They are the first place where oxygen and nutrients are given to the tissue, while waste is removed.
Once a person has finished using the oxygen and nutrients in the tissue, they are carried back to the heart in the veins. These are the same veins that are used by the lungs to exchange gasses, which is why they’re called the pulmonary system. Both of these systems work together to create a circuit that keeps blood moving around the entire body, which is necessary for the survival of each individual cell.
Your arteries carry oxygen-rich blood throughout the body. They eventually branch into the smallest blood vessels, capillaries, where wastes and nutrients are exchanged with tissues.
Arteries have thick walls to withstand the pressure of blood flowing through them. The walls are made of a layer of smooth muscle cells, surrounded by a layer of connective tissue called the tunica media. This middle layer is thicker in arteries than veins.
As blood flows from arteries into smaller blood vessels, the pressure against the walls decreases. This is because fewer and thinner blood vessels are present in these lower-pressure zones. The tiniest blood vessels, capillaries, are found in the microcirculation of tissues, which also contains specialized blood vessels known as endothelium.
The endothelium is a layer of thin cells that lines the inside of blood vessels, including capillaries. This cell layer is anchored by proteins to the wall of the capillary. It is through this layer that the body’s cells get the nutrients and oxygen they need to live. Capillaries are also the primary site of passive diffusion, a process through which your cells move substances across the capillary walls.
In addition to blood flow, capillaries play a role in your body’s immune system. When your cells are damaged or die, they release chemicals that alert the immune system to this fact. The immune system then responds by sending molecules into the capillaries to cause them to leak, a process known as pinocytosis. The substances that are leaked from the capillaries allow the immune system to identify and kill cells that have become damaged or dead.
After delivering nutrients and oxygen to the tissues, capillaries return deoxygenated blood to the heart through their own network of microscopic vessels called post-capillary venules. The venules are tiny and thin-walled, but they contain one-way valves to prevent blood from flowing back in the wrong direction.
If your capillaries aren’t working properly, you may experience a wide range of symptoms, from mild to serious. The good news is that the same lifestyle choices that keep your arteries healthy can help to preserve your capillaries as well. Talk to your healthcare provider about the best ways to do so.
The vascular system supplies every organ and tissue of your body with oxygen and nutrients, removes waste materials, and maintains fluid balance. It also transports deoxygenated blood back to the heart from capillaries, venules, and veins. Blood vessels transport oxygen, glucose (blood sugar), amino acids, and other essentials to your cells, and removes carbon dioxide, urea nitrogen, and other wastes from your cells. In addition, your heart transports blood from the lungs back to the vascular system.
The walls of your blood vessels are made of three layers of muscle-like tissue called tunics. The inner layer, the tunica intima, is a thin layer of simple squamous epithelium surrounded by a basement membrane and varying amounts of connective tissue and elastic fibers. The middle layer, the tunica media, is thicker in arteries than in veins and contains layers of circular smooth muscles that contract and relax to regulate blood flow and pressure. The outermost layer, the tunica externa or tunica adventitia, is a thick band of connective tissue with varying amounts of elastic fibers and polysaccharide substances.
Your vascular system includes your veins, small and large arteries, and pulmonary and portal venous systems that bring blood from the lungs to the heart. Your vascular system is divided into two circuits, the systemic and the pulmonary, to allow for refueling and maintenance of your blood.
Like arteries, veins have thick walls that can withstand high blood pressures. However, unlike arteries, veins have larger lumens and thinner walls that allow them to distend more readily. This characteristic, known as high capacitance, allows veins to store a large percentage of their blood volume at low pressures.
Venules are the smallest type of blood vessel in your vascular system. They are microscopic post-capillary structures that deliver low-oxygen blood to arteries and capillaries. The venous system consists of a network of small and large veins that transport deoxygenated blood back to the heart through one-way valves.
When a vein wall weakens or breaks down, clots may form and obstruct the blood flow through the vessel. The most serious complication is a deep vein thrombosis, which occurs when a blood clot forms in a deep vein in your leg. Less serious venous conditions include superficial thrombophlebitis and varicose veins.