The three groups significantly differed with regard to the SDANN
index ( P = 0.
Variables derived from the direct measurement of RR intervals (SDNN and SDANN
SDNNIDX) are global indices of HRV and reflect long-term components, circadian rhythm, physical activity and postural changes (SZTAJZEL, 2004).
The r-values show that age was inversely correlated with all the indices of heart rate variability, however the correlation was significant only for SDNN and SDANN
(p-value < 0.
reflects sympathetic tension, which was associated with the slow changes in heart rate.
As alteracoes mais significativas, como aumento em SDNN, pNN50, RMSSD, LF, HF, razao LF/ HF, SDANN
, foram observadas comparando-se as medidas pre e pos-treinamento, em momentos nos quais os sujeitos nao estavam praticando a tecnica (em repouso), demonstrando que esta possibilita a manutencao da autorregulacao autonoma fora do momento de treinamento.
, pNN50, and LFnu were similar in both groups, however RMSSD, pNN50, HFnu, LF/HF ratio, TS (p < 0.
This was particularly obvious during interpolation of gathered data displayed on Figure 1 (A/B) regarding SDANN
10 We considered time domain parameters; SDNN (standard deviation of R-R intervals), SDANN
(standard deviation of average NN intervals), SDNNi (SDNN index; a measures of variability due to cycles shorter than 5 minutes), RMSSD (square root of the mean squared differences of successive NN intervals), and pNN50 (the number of interval differences of successive NN intervals greater than 50 ms (NN50)/total number of NN intervals).
Analysis showed that among HRV measures, decreased LF, LF/HF ratio, SDANN
, and SDNN were significant predictors of cardiac death (see Table 6).
Patients without NSVT had slightly below-normal parameters for their NN intervals and pNN50 measurements but remained within normal limits on their SDNN and SDANN
Heart rate variability parameters SDNN 24 hour 77 SDANN
index, ms 61 SDNN index, ms 58 rMSSD 24 pNN50, % 3 Spectral power-24 hour, 4633.
(standard deviation of all 2-min RR interval averages) reflects changes in both sympathetic and parasympathetic tone and provides information about the variability over a longer cycle, such as diurnal changes.