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Heart Disease Health Center

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Heart Disease Glossary of Terms


Heart Failure (congestive heart failure, CHF): A condition where the heart muscle weakens and cannot pump blood efficiently. Fluid accumulates in the lungs, hands, ankles, or other parts of the body.

Heart Lung Bypass Machine: A machine that oxygenates the blood and circulates it throughout the body during surgery.

Heart Surgery: Heart surgery is any surgery that involves the heart or heart valves.

Heart Valves: There are four valves in the heart: the tricuspid and the mitral valve, which lie between the atria and ventricles, and the pulmonic and aortic valves, which lie between the ventricles and the blood vessels leaving the heart. The heart valves help to maintain one-way blood flow through the heart.

Hemoglobin: A protein in red blood cells that transports oxygen and carbon dioxide and gives blood its red color.

Hibernating Myocardium: After a heart attack, some areas of heart muscle do not pump as they should. Some areas will have permanent damage. Other areas are able to return to their normal function if blood flow is returned to that area by medications or a procedure. Hibernating myocardium is heart muscle that is "resting" and may possibly return to normal function.

High-Density Lipoprotein (HDL): Lipoprotein particle in the blood. HDL is known as "good" cholesterol because it deposits cholesterol in the liver, where it is excreted by the body. High HDL is thought to protect against coronary artery disease.

Holter Monitor: A small recorder (monitor) is attached to electrodes on your chest. It records the heart's rhythm continuously for 24 hours. After the monitor is removed the heart's beats are counted and analyzed by a technician with the aid of a computer. Your doctor can learn if you are having irregular heartbeats, what kind they are, how long they last, as well as what may cause them.

Homocysteine: An amino acid. High levels of homocysteine are a risk factor for coronary artery disease. However, treatment of high homocysteine levels have not been shown to lower the risk of heart disease.

Hydrogenation: A process used to harden unsaturated liquid vegetable oils into saturated fats.

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