Vascular System: Arteries & Veins

The vascular system is made up of the vessels that carry our blood. Arteries carry oxygen-rich blood away from the heart. Veins carry oxygen-poor blood back to your heart. There is one exception to that statement; when the blood starts its vascular system trip at the right side of the heart, it is the pulmonary artery that carries the oxygen-poor blood to the lungs where it exchanges carbon dioxide for oxygen. Then the pulmonary vein carries oxygen-rich blood back to the heart. The blood goes back to the left side of the heart and is pumped out to the rest of the body. The main artery leading from the heart to the rest of the body is called the aorta. As the blood travels, it enters smaller and smaller blood vessels, reaching every cell in the body, dropping off nutrients and picking up waste products and carbon dioxide. The blood then starts the trip back in the veins, entering larger and larger ones as it goes, passing through the liver on the way to drop off waste products. The blood eventually arrives back at the right side of the heart to start the trip all over again.

Vascular problems

As we age, our arteries tend to thicken, get stiffer and narrow. That is called arteriosclerosis. A form of arteriosclerosis is atherosclerosis. (Read about "Arteriosclerosis & Atherosclerosis") Atherosclerosis is the build-up of plaque and cholesterol in large and medium sized arteries. (Read about "Cholesterol") A narrowing of the arteries from a build-up of plaque can lead to coronary heart disease (Read about "Coronary Heart Disease") This can affect even the smallest arteries in the body, for example the tiny arteries that feed the heart. (Read about "Coronary Microvascular Disease")

Narrowing of the arteries in other places, such as the legs, can cause what is called peripheral arterial disease or PAD. (Read about "Peripheral Arterial Disease") When the smaller arteries are affected, it is called arteriolosclerosis. The kidneys, spleen and the pancreas can be damaged. (Read about "Kidney Disease" "The Spleen") High blood pressure is often a cause of arteriolosclerosis. (Read about "Hypertension: High Blood Pressure")

Diseases such as Marfan Syndrome can weaken the walls of major arteries. (Read about "Marfan Syndrome") Raynaud's phenomenon is a disorder that affects the blood vessels in the fingers, toes, ears and nose, causing the blood vessels to constrict or narrow. (Read about "Raynaud's Phenomenon")

Clots (thrombi) are lumps of blood that has been converted from a liquid to a solid state. This is called coagulation. A clot can form and block the flow of blood to the heart, leading to a heart attack. (Read about "Heart Attack") The same situation in the arteries leading to the brain (Read about "The Brain") can cause strokes. (Read about "Stroke")

Clots in the veins can result in deep vein thrombosis or DVT (Read about "Deep Vein Thrombosis"), phlebitis, and other problems. If those clots break free, they become emboli. Those emboli can lodge somewhere else resulting once again in life-threatening situations such as heart attacks, strokes and pulmonary embolism. (Read about "Pulmonary Embolism") In addition, as part of the system of moving the blood back to the heart, the veins have small one way valves. If those valves weaken, the blood can back up, pool and cause the veins to swell. The result is varicose veins. (Read about "Varicose Veins")

Any blood vessel can develop an aneurysm. It happens when the wall of the blood vessel is weakened by disease or injury. A bulge develops, sort of like a bubble on a weakened tire. Aneurysms can be deadly if they burst, particularly ones in the aorta or the brain. (Read about "Aneurysms")

We can also be born with or develop what are called vascular lesions. A vascular lesion is an abnormal cluster of snarled blood vessels. Although vascular lesions can occur throughout the body, those located in the brain or spinal cord - the two parts of the central nervous system - can have especially widespread effects on the body. (Read about "Vascular Lesions of the Central Nervous System" "The Brain" "Nervous System") Some of the types of vascular lesions that occur on the central nervous system include:

• arteriovenous malformations (AVMs)
• capillary telangiectases
• cavernous malformations
• venous malformations

Vasculitis

The National Institute of Neurological Disorders and Stroke (NINDS) defines vasculitis as an inflammation of the blood vessel system, which includes the veins, arteries and capillaries. Vasculitis may affect blood vessels of any type, size or location, and therefore can cause dysfunction in any organ system, including the central and peripheral nervous systems. (Read about "Nervous System") The symptoms of vasculitis depend on which blood vessels are involved and what organs in the body are affected. The disorder may occur alone or with other disorders such as temporal arteritis. Temporal arteritis (also called cranial or giant cell arteritis) is an inflammation of the temporal artery (which runs over the temple, beside the eye). Symptoms of this disorder may include stiffness, muscle pain, fever, severe headaches, pain when chewing and tenderness in the temple area. Other symptoms may include anemia (Read about "Anemia"), fatigue, weight loss, shaking, vision loss and sweats.

Treatment for vasculitis depends on the severity of the disorder and the individual's general health, according to NINDS. Treatment may include cortisone or cytotoxic drugs. Other treatments may include plasmapheresis (the removal and reinfusion of blood plasma), intravenous gamma globulin and cyclosporin. (Read about "Infusion Therapy") Some cases of vasculitis may not require treatment. Treatment for temporal arteritis and its associated symptoms generally includes corticosteroid therapy. Early detection of temporal arteritis and immediate treatment are essential to prevent vision loss.

The prognosis for individuals with vasculitis varies depending on the severity of the disorder. Mild cases of vasculitis are generally not life threatening, while severe cases (involving major organ systems) may be permanently disabling or fatal. The prognosis for individuals with temporal arteritis is generally good. With treatment, most individuals achieve complete remission; however, vision loss may be irreversible.

Related Information:

    The Heart & Its Valves

    Heart Disease & Women

    Cardiovascular Tests

    Marfan Syndrome

    Sickle Cell Disease

    Glossary of Stroke Terms

    Glossary of Heart Terms