The use of nuclear magnetic resonance to produce images of the molecules that make up a substance, especially the soft tissues of the human body. MRI is used in medicine to diagnose disorders of body structures that do not show up well on x-rays.

An instrument used to identify chemicals in a substance by their mass and charge.

The valve between the left atrium and the left ventricle of the heart.

A heart problem in which the valve that separates the upper and lower chambers of the left side of the heart does not close properly.

Abnormal sounds heard by stethoscope when listening to the heartbeat cycle Ñ such as whooshing or swishing Ñ made by turbulent blood in or near the heart.

A drug that reduces pain and soreness associated with sprains, strains, or other types of muscle injury.

Any heritable change in DNA sequence.

Destruction of heart tissue resulting from obstruction of the blood supply to the heart muscle.

Insufficient blood flow to part of the heart.

The muscle tissue of the heart.