You searched for: “ballistocardiograph
ballistocardiograph (s) (noun), ballistocardiographs (pl)
1.The graphic recording of movements of the body imparted by ballistic forces or the cardiac contraction and ejection of blood, ventricular filling, acceleration, and deceleration of blood flow through the great vessels.

These minute movements or ballistocardiographs are amplified and recorded on a moving paper chart after being translated into an electrical potential by a pickup device.

2. An instrument for recording the movements of the body caused by ejection of blood from the ventricles at each beat of the heart.