The adrenal glands are located above the kidneys. The hormones produced by the adrenal glands affect nearly every organ in the body. The inner layer of the adrenal gland releases substances (hormones) such as adrenaline that: Help control blood pressure. Help the body react to stress by increasing heart rate, opening...

Heatstroke occurs when the body fails to regulate its own temperature, and body temperature continues to rise. Symptoms of heatstroke include: Unconsciousness for longer than a few seconds. Confusion, severe restlessness, or anxiety. Convulsion (seizure). Symptoms of moderate to severe difficulty breathing. Fast heart...

Blood thinners are medicines that prevent blood clots. They do not actually thin the blood but increase the time it takes to form a blood clot. They also help prevent existing blood clots from becoming larger. They may be used to prevent or to treat certain blood vessel, heart, or lung conditions. The term "blood...

A pacemaker is a small, battery-powered device that sends out small electrical impulses to make the heart beat in a regular rhythm and at a normal speed. A pacemaker consists of a pulse generator and battery that create the electrical impulses. Most pacemakers have wires (leads) that transmit electricity to the heart. A...

Discusses infection of the heart's valves or inner lining (endocardium). Covers cause by bacteria (bacterial endocarditis) or fungi (fungal endocarditis). Looks at symptoms like fever. Covers treatment with medicines or possibly surgery.

An echocardiogram (also called an echo) is a type of ultrasound test that uses high-pitched sound waves that are sent through a device called a transducer. The device picks up echoes of the sound waves as they bounce off the different parts of your heart. These echoes are turned into moving pictures of your heart that...

Rheumatic fever results from an infection caused by certain strains of streptococcal bacteria and may be triggered by a strep infection (most often strep throat) that has not been treated. Proper treatment of strep infection can prevent rheumatic fever. Rheumatic fever affects the joints and heart, causing symptoms...

Graves' disease is an autoimmune disorder that affects the thyroid gland, which produces hormones that control many of the body's functions. Graves' disease causes the thyroid gland to produce too much thyroid hormone (hyperthyroidism), which may make a person's heart pound and beat irregularly and may cause...

What do your blood pressure numbers mean? Blood pressure is a measure of how hard the blood pushes against the walls of your arteries as it moves through your body. Blood pressure readings include two numbers. The top (systolic) number shows how hard the blood pushes when the heart is pumping. The bottom (diastolic)...

It's normal for blood pressure to go up and down throughout the day. But if it stays up, you have high blood pressure. For diagnosis, the top number may be 130 to 140 or higher. The bottom number may be 80 to 90 or higher. High blood pressure increases the risk of stroke, heart attack, and other problems. You and your...

Helping or caring for a loved one with a long-term (chronic) condition, such as COPD or heart failure, can feel like a lot to take on. Sometimes it can be hard for people to accept help. Or they may choose not to accept help. So you may have to adjust the way you think, ask, listen, and respond. These tips might help...

Pediatricians are medical doctors who specialize in the care of children. Pediatricians can treat children who have any type of problem, or they may specialize in specific areas, such as: Adolescent medicine (conditions and diseases common to teenagers). Cardiology (diseases and conditions of the heart and blood...

Vital signs include heart rate, respiration (breathing rate), blood pressure, and temperature. Knowing the ranges for vital signs for your child can help you notice problems early or relieve concerns you may have about how your child is doing. 0 to 12 months old Vital signs for infants ages 0 to 12 months include the...

Cholesterol is a type of fat (lipid) in your blood. High cholesterol means that you have too much of the fat in your blood. Your body needs some cholesterol. But if you have too much, it can build up in your arteries and increase your risk of heart attack and stroke.

A person who is unconscious is not aware of what is going on around him or her. He or she may not be able to make purposeful movements. A person may become unconscious from an injury or a health condition. Fainting or a seizure disorder (epilepsy) may cause unconsciousness that is usually brief. Heart problems, such as...

Tony has done well with getting his cholesterol under control. And he's had a notable failure. But as Tony tells it, "I've learned as much from the failure as I have from the success. Maybe more." About 2 years ago, Tony's doctor told him that he had a high risk for heart attack and that his cholesterol was high. So...

Electrolytes are minerals found naturally in the body, such as potassium, calcium, sodium, and magnesium. Electrolytes are needed to keep the body's balance of fluids at the proper level and to maintain normal functions, such as heart rhythm, muscle contraction, and brain function. If the body's electrolytes are not in...

Sally never had to worry about her weight. She had always been active, enjoying her daily walks in the park. But things changed when Sally's mom had a heart attack. Sally took care of her mom night and day. But Sally got so busy taking care of her mom that she forgot to take care of herself. For months, Sally didn't do...

Guides through decision to have a PSA test to check for prostate cancer. Includes what PSA results tell you and what they do not. Covers benefits and risks. Includes an interactive tool to help you decide.