The cardiovascular system consists of the heart and blood vessels as it primary organs, and functions to circulate blood throughout the body. The American Heart Association explains that the main cardiovascular organ, the heart, pumps blood...
Blood vessels deliver blood from the heart to the tissues, and return oxygen-depleted blood to the heart. The vascular system is made up of three vessel types. Arteries carry blood away from the heart, veins return blood to the heart, and the tiny...
The Harvard Medical School Family Health Guide defines normal blood pressure as a systolic pressure of less than 120 and a diastolic pressure of less than 80. Systolic pressure represents the force of the blood on the artery walls as the heart...
The normal heart rate for an average adult is 60 to 100 beats per minute. This number can increase to a maximum heart rate during exercise that varies with age. Your heart rate, both at rest and during exercise, is controlled by the nervous...
Cardiovascular disease affects millions of people around the globe, and cardiovascular or aerobic exercise is one of the most effective ways to boost heart health. Aerobic exercise changes your heart for the better by challenging this most...
According to an article published in the January/February 2007 edition of Health Affairs, 152,000 coronary artery bypass graft procedures were done in 2003. The article goes on to state that this is one of the most frequently performed surgeries...
Chemotherapy drugs, administered to treat cancer, can cause scarring and collapse of veins, making it hard to start intravenous lines. Ports buried partially or completely under the skin connect to catheters that terminate in large veins, reducing...
When more than one coronary artery is blocked, coronary artery bypass surgery may be recommended, according to the Society of Thoracic Surgeons, Bypass surgery re-establishes blood flow to the heart by bypassing the blockages. This provides...
No part of the body is without access to a blood supply. The human heart is a hollow, pulsating muscle located above the diaphragm and slightly left of the midline of the chest. Its rhythmic beating keeps body fluids mixed by constantly forcing...
The cardiovascular system plays a crucial role in the body by providing oxygen and nutrients to the cells of the body and removing waste from them. The system is a pump with a circle of tubing running away from the pump toward the tissues and then...
When blood vessels are narrowed and lose flexibility, the pressure of blood moving through them goes higher and the heart has to work harder. High blood pressure, or hypertension, may be present for years without symptoms. Pressure goes up and...
Your heart is a muscle that sits on the left side of your chest. It is about the size of your fist, and it beats, on average, about 70 times each minute. When you start to work, your muscles need more oxygen and sugar to make fuel. Your heart...
Blood circulation goes in a circle, which makes sense, given its name. Arteries carry blood away from the heart, and veins return blood to the heart. With one exception, blood carried away from the heart is oxygenated blood, and blood returning in...
The heart supplies the rest of the body with oxygenated blood. This may lead people to wonder how the heart muscle and tissue itself are supplied with oxygenated blood. The answer is simple: The heart gets oxygenated blood from itself. Oxygenated...
Many older men get up at night to urinate, and may consider it normal. However, nocturia--the medical term for waking up needing to urinate--can be caused by serious disease. Nocturia is common: British urologist Lucy Abraham and colleagues note...
A normal heart rate is between 80 and 100 beats per minute. This is how many times the heart pumps per minute in order to pump blood to the rest of the body. According to the American Heart Association, a rate greater than 100 beats per minute is...
Exercise increases heart rate, which may be closely monitored under certain training regimens. Breathing also increases and the skin produces sweat. In fact, breathing and sweat production are processes that respond to and benefit from an...
The heart, divided into four chambers, functions to pump blood, oxygen and nutrients throughout the body. Electrical impulses produced by specialized cells in the upper right chamber, known as the right atrium, travel through the upper chambers...
Caffeine is among the most widely consumed stimulants in the world. According to Medline Plus of the National Institutes of Health, caffeine has many effects on the body, including central nervous system stimulation, which can make you more alert...
Cardiac abnormalities can affect the structure and/or the function of the heart. Some of the abnormalities affect the cardiac muscle layer and interfere with its ability to function. An abnormal structure in the cardiac valves, tumors and abnormal...
The heart operates by electrical impulses to circulate blood throughout the body. A group of cells in the atrium of the heart functions as an automatic pacemaker, generating electrical current that powers synchronized contractions of heart muscle....
The heart and the circulatory system are the components of the cardiovascular system. The function of the cardiovascular system is to circulate blood through out the body.The healthy heart beats on average of 100,000 times daily. It receives...
Approximately one in 500 children develop hydrocephalus, excessive cerebrospinal fluid accumulation in the ventricles of the brain, the National Institute of Neurological Disorders and Stroke states. Obstruction of cerebrospinal fluid drainage or...
The circulatory system, made up of a pumping organ--the heart--and a network of pipes--the blood vessels--is responsible for carrying oxygen and nutrition toward and metabolic waste away from the body cells. While the circulatory system forms a...
The heart is responsible for the circulation of nutrient-rich blood and the removal of wastes from the cells. It works in conjunction with the lungs to carry oxygen to tissues throughout the body. The heart beats continually and does not depend on...
The symptoms of fatigue, shortness of breath, and dizziness can seem harmless when they present as individual symptoms. Everyone will feel one or more of these symptoms at some point in their lives. When these symptoms occur together, however,...
The circulatory system is a closed network of transport vessels responsible for delivering nutrients and removing waste products from all body systems. Shirley A. Jones's "Pocket Anatomy and Physiology" provides a pictorial guide illustrating the...
DC or direct current cardioversion is a therapeutic procedure used to treat abnormal heartbeats. The medical term for abnormal beats is cardiac arrhythmia. An arrhythmia can be a fast or slow heart rhythm. Cardioversion treatment uses electricity...
A developing human embryo mimics human evolution. The consecutive stages of the embryo's developing respiratory system resemble the respiratory systems found in fish, amphibians, reptiles and lower mammals. The fetus gets its oxygen and nutrients...
Mitral stenosis is a vavular heart disease denoting the narrowing of the heart's mitral valve. Learn more about mitral stenosis and the heart in this health video.
