A new method for measuring the ballistocardiogram using EMFi sensors in a normal chair.

Ballistocardiography is a non-invasive technique for the assessment of cardiac function. We built a measurement setup to measure the ballistocardiogram from a normal chair using EMFi sensors. The ballistocardiogram is recorded from a subject sitting on the chair. The measured signal is amplified by a specially-designed charge amplifier and digitized by a circulation monitor. A PC provides a user interface for the measurement devices, records the data and displays the results. Impedance cardiography and ECG serve as reference measurements for the ballistocardiography. To test the system, one healthy 24-year-old male and one healthy 22-year-old female were measured. It is concluded that the ballistocardiogram waveforms described in the literature can be recognized from the EMFi signal measured from a normal chair.