The Use of Fetal Noninvasive Electrocardiography

Table 3

Fetal HRV and morphological noninvasive ECG parameters in the study population.

Index	Group I	Group II	Group III
SDNN, ms	45.8 13.1	29.4 8.3	10.2 4.5
RMSSD, ms	22.4 3.4	14.2 2.6	8.1 0.8
pNN5O, %	8.7 2.5	5.9 1.8	2.0 0.5
АМо, %	39.6 14.1	50.2 11.6	65.9 13.4
SI, c.u.	169.3 42.7	496.1 65.8	1467.3 405.8
TP, ms^2	1513.6 329.1	896.2 163.5	424.9 93.7
VLF, ms^2	1252.8 248.3	692.8 91.3	251.8 44.2
LF, ms^2	184.3 26.5	151.9 34.1	135.0 19.6
HF, ms^2	77.6 9.4	53.6 8.2	38.9 10.4
QT, ms	222.5 28.6	209.2 25.1	194.8 31.3
QRS, ms	64.3 11.8	64.6 10.2	65.7 11.9
T, mcV	2.8 0.5	4.4 1.6	8.2 2.1
T/QRS	0.04 0.01	0.08 0.03	0.20 0.05

Notes: , the differences were statistically significant compared to Group I (); , the differences were statistically significant compared to Group II ().
SDNN: standard deviation of normal to normal intervals; RMSSD: root mean square of successive heartbeat interval differences; pNN50: the proportion of the number of pairs of NNs that differ by more than 50 ms divided by total number of NNs; AMo: the amplitude of mode (the most frequent value of NN interval or the highest column in the histogram) − number of NN intervals included in the pocket corresponding to mode measured in percentage (%); SI: stress index (SI) = AMo (%)/(2 Mo Var); Var = −; TP: total power; VLF: very low frequency; LF: low frequency; and HF: high frequency.