Journal of Ophthalmology / 2015 / Article / Tab 2

Research Article

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.


Frequency domainULFPower (=variability) in “ultra low frequency” range (0–0.0033 Hz)
VLFPower (=variability) in “very low frequency” range (0.0033–0.04 Hz)
LFPower (=variability) in “low frequency” range (0.04–0.15 Hz)
HFPower (=variability) in “high frequency” range (0.15–0.4 Hz)
XHFExtended high frequency band from 0.15 to 0.6  Hz
XFFrequency band from 0.12 to 0.18  Hz
PTotal power density spectra (variance of all NN intervals ≤0.4 Hz)
LF/HFRatio of LF and HF
LF/PRatio of LF and P
HF/PRatio of HF and P
XHF/PXRatio of XHF and the extended total power
(variance of all NN intervals ≤0.6 Hz)
VLF/PRatio of VLF and P
ULF/PRatio of ULF and P
(ULF + VLF + LF)/PRatio of (ULF + VLF + LF) and P
(ULF + VLF)/PRatio of (ULF + VLF) and P
UVLFSum of ULF, VLF, and LF (≤0.15 Hz)
LFNNormalized low frequency
HFNNormalized high frequency