What is "ballistocardiography"

n. The science of the preparation and diagnostic interpretation of ballistocardiograms.

The ballistocardiograph (BCG) is a measure of ballistic forces on the heart. Ballistocardiography is a technique for producing a graphical representation of repetitive motions of the human body arising from the sudden ejection of blood into the great vessels with each heart beat. It is a vital sign in the 1-20 Hz frequency range which is caused by the mechanical movement of the heart and can be recorded by noninvasive methods from the surface of the body. It was shown for the first time, after an extensive research work by Dr. Isaac Starr, that the effect of main heart malfunctions can be identified by observing and analyzing the BCG signal.

One Example of the use of a BCG is a ballistocardiographic scale, which measures the recoil of the persons body who is on the scale. A BCG scale is able to show a persons heart rate as well as their weight.

The term ballistocardiograph originated from the Roman ballista, which is derived from the Greek word ballein (to throw), a machine for launching missiles, plus the Greek words for heart and writing.