Table 2 Features derived from BVP signal and their explanations
BVP feature | Feature description |
|---|---|
HR | A straightforward measurement of heartbeats per minute.= |
BVP PSD | PSD of BVP signal between 1 and 8 Hz |
MAD | A measure of heart variability |
IBI | The time interval between successive heartbeats, useful for assessing HRV. |
SDNN | Quantifies overall variability in heart rate, reflecting ANS function. |
SDSD RMSSD | SDSD and RMSSD analyze the variability of successive heartbeat intervals, with RMSSD particularly sensitive to parasympathetic activity |
pNN20 pNN50 | Percentages of differences between adjacent R-R intervals,greater than 20 ms and 50 ms, respectively, indicators of rapid changes in heart rate. |
SD1 | Std of points perpendicular to the line of identity, indicating short-term HR variability. |
SD2 | Standard deviation along line of identity, reflecting long-term variability. |
S | Quantifies scatter of points within plot, indicating overall heart rate variability. |
SD1/SD2 ratio | Provides insights into balance between short-term and long-term heart rate variabilities, reflecting relative contributions of sympathetic and parasympathetic inputs to heart rate dynamics. |
BR | Estimated breathing rate extracted from BVP signal |