January 01, 2018

A chair based ballistocardiogram time interval measurement with cardiovascular provocations

  • Ahmaniemi T.
  • Lindholm H.
  • Muller K.
  • Rajala S.
  • Taipalus T.

The objective of this study was to measure ballistocardiogram (BCG) based time intervals and compare them with systolic blood pressure values. Electrocardiogram (ECG) and BCG signals of six subjects sitting in a chair were measured with a ferroelectric film sensor. Time intervals between ECG R peak and BCG I and J waves were calculated to obtain RJ, RI and IJ intervals. The time intervals were modified with two cardiovascular provocations, controlled breathing and Valsalva manoeuvre. The controlled breathing changed all the time intervals (RJ, RI and IJ) whereas the Valsalva manoeuvre mainly caused variations in the RJ and RI intervals. The time intervals calculated from the ECG and BCG signals may provide new parameters that can be used to evaluate heart health. Especially the BCG based parameters may be unobtrusively measured as the BCG sensors do not need direct contact between the sensor and skin. In future, the measurement system presented in this study might be used as a comfortable home monitoring chair measuring relative systolic blood pressure changes.

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