Table 2 Time Domain HRV Parameters
Time-domain indices | Description |
|---|---|
Mean RR interval | The average NN interval per hour; a single 24 hour average will be reported. |
SDNN | Standard deviation of the NN interval every hour; a single 24-hour average will be reported. |
SDNNi | Standard deviation of the NN interval in every 5 minutes; a single 24-hour average will be reported. |
RMSSD | The root mean square of successive differences of adjacent NN intervals; a single 24-hour average will be reported. |
sNN50 | Number of pairs of adjacent NN intervals differing by >50 ms; a single 24-hour value for the increases, decreases and total will be reported. |
Triangular Index | Total number of all NN intervals divided by the height of the histogram of all NN intervals measured on a discrete scale with bins of 1/128s; a single 24-hour average will be reported. |
sNN6% | Number of pairs of adjacent NN intervals differing by >6%; a single 24-hour value for the increases, decreases and total will be reported. |
VPC > 10%/hour | The number of hourly segments with > 10% SVE and VPCs will be reported and the absolute number of SVE and VPCs will also be reported. |