Blood Pressure and Heart Rate Variability to Detect Vascular Dysregulation in Glaucoma
Table 2
Description of parameters calculated by frequency domain analysis. Parameters were calculated for heart rate and systolic and diastolic blood pressure.
Method
Parameter
Description
Frequency domain
ULF
Power (=variability) in “ultra low frequency” range (0–0.0033 Hz)
VLF
Power (=variability) in “very low frequency” range (0.0033–0.04 Hz)
LF
Power (=variability) in “low frequency” range (0.04–0.15 Hz)
HF
Power (=variability) in “high frequency” range (0.15–0.4 Hz)
XHF
Extended high frequency band from 0.15 to 0.6 Hz
XF
Frequency band from 0.12 to 0.18 Hz
P
Total power density spectra (variance of all NN intervals ≤0.4 Hz)
LF/HF
Ratio of LF and HF
LF/P
Ratio of LF and P
HF/P
Ratio of HF and P
XHF/PX
Ratio of XHF and the extended total power (variance of all NN intervals ≤0.6 Hz)