| Increasing fluctuation amplitude |
| amplitude |
20–95 inter-quantile distance of detrended NN intervalseries |
Fluctuation range of heart beat intervals above an approximated baseline |
| Increasing complexity |
| gMSE(3) |
Generalized Mutual Information at coarse graining level 3of NN interval series |
Complexity of heart rate patterns essentially modulated by complex sympatho-vagal rhythms |
| Pattern formation |
| skewness |
Skewness of NN interval series |
Asymmetry, contribution of vagal and sympathetic activity with their different time constants, decline of decelerations and formation of acceleration patterns |
| pNN5 |
Percentage of differences between adjacent NN intervalsthat are >5 ms. |
Formation of vagal rhythms |
| VLF/LF |
Ratio between very low (0.02–0.08 Hz) and low(0.08–0.2 Hz) Frequency band power |
Baseline fluctuation in relation to sympatho-vagal modulations |
| Traditional fetal heart rate indices |
| meanHR |
Average over all NN interval related values of 60,000/NN |
Mean heart rate in bpm |
