Heart and Blood Vessel Disorders

The heart and blood vessels constitute the cardiovascular (circulatory) system. The heart pumps the blood to the lungs so it can pick up oxygen and then pumps oxygen-rich blood to the body. The blood circulating in this system delivers oxygen and nutrients to the tissues of the body and removes waste products (such as carbon dioxide) from the tissues.

Disorders that affect the heart or blood vessels are called cardiovascular disorders. Cardiovascular disorders are usually divided into

Sometimes, medical history and physical examination alone suggest to a doctor that the person has a heart or blood vessel disorder. However, special diagnostic procedures are often needed to confirm the diagnosis, determine the extent and severity of the disease, and help plan treatment.

Abnormal heart rhythms (arrhythmias) are sequences of heartbeats that are irregular, too fast, too slow, or conducted via an abnormal electrical pathway through the heart.

The aorta, which is about 1 inch (2.5 centimeters) in diameter, is the largest artery of the body. It receives oxygen-rich blood from the left ventricle and distributes it to all of the body except the lungs (which receive blood from the right ventricle). Just after the aorta leaves the heart, smaller arteries that carry blood to the head and arms branch off. The aorta then arches down, with additional smaller arteries branching off along its route from the left ventricle to the lower abdomen at the top of the hipbone (pelvis). At this point, the aorta divides into the two iliac arteries, which supply blood to the legs.

Atherosclerosis is a condition in which patchy deposits of fatty material (atheromas or atherosclerotic plaques) develop in the walls of medium-sized and large arteries, leading to reduced or blocked blood flow.

Cardiomyopathy refers to progressive impairment of the structure and function of the muscular walls of the heart chambers.

Coronary artery disease is a condition in which the blood supply to the heart muscle is partially or completely blocked.

Infective endocarditis is an infection of the lining of the heart (endocardium) and usually also of the heart valves.

Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or other changes that may further weaken or stiffen the heart.

A tumor is any type of abnormal growth, whether cancerous (malignant) or noncancerous (benign). Tumors in the heart may be

Heart valves regulate the flow of blood through the heart's four chambers—two small, round upper chambers (atria) and two larger, cone-shaped lower chambers (ventricles). Each ventricle has a one-way "in" (inlet) valve and a one-way "out" (outlet) valve. Each valve consists of flaps (cusps or leaflets) that open and close like one-way swinging doors.

High blood pressure (hypertension) is persistently high pressure in the arteries.

Low blood pressure is blood pressure low enough to cause symptoms such as dizziness and fainting. Very low blood pressure can cause damage to organs, a process called shock.

The lymphatic system is a vital part of the immune system. It includes organs such as the thymus, bone marrow, spleen, tonsils, appendix, and Peyer patches in the small intestine that produce and process specialized white blood cells that fight infection and cancer.

Pericardial disease affects the pericardium, which is the flexible two-layered sac that envelops the heart.

Peripheral arterial disease results in reduced blood flow in the arteries of the trunk, arms, and legs.

Athlete's heart refers to the normal changes that the heart undergoes in people who regularly do strenuous aerobic exercise (for example, higher intensity running or bicycling) and also in those who do higher intensity weight training exercise (weight lifting).

Veins return blood to the heart from all the organs of the body. The large veins parallel the large arteries and often share the same name, but the pathways of the venous system are more difficult to trace than those of the arteries. Many unnamed small veins form irregular networks and connect with the large veins.