Skip to main content

Table 1 Description of parameters related with the radial artery pulse-pressure wave and other bio-signal characteristics

From: Hemodynamic changes caused by acupuncture in healthy volunteers: a prospective, single-arm exploratory clinical study

Variable (units) Description
Radial pressure pulse wave
 SE0-10Hz (Vrms 2, 10−1) Sum of the spectral energy within 0–10 Hz
 SE10-30Hz (Vrms 2, 10−3) Sum of the spectral energy within 10–30 Hz
 PPI (V) Pulse power index; Maximum amplitude of the voltage response in radial artery pulse
 PDI (mm) Pulse depth index; measure of the pulse depth based on the sensor displacement in the direction normal to the skin surface
 Systolic area (Vs) Area of systolic phase in average pulse
 Diastolic area (Vs) Area of diastolic phase in average pulse
 SEVR (%, 10−2) Subendocardial viability ratio; ratio between the diastolic and systolic area
 AIX (%) Radial augmentation index normalized to a heart rate of 75 bpm; (late systolic pressure/systolic pressure) × 100
Heart rate variability
 NN (s) Normal to normal interval
 SDNN (ms) Standard deviation of the NN interval
 RMSSD (ms) Square root of the mean squared differences of NN intervals
 TF (ms2) Total frequency power within 0–0.4 Hz
 LF (ms2) Low frequency power within 0.04–0.15 Hz
 HF (ms2) High frequency power within 0.15–0.4 Hz
 nLF (%) LF power in normalized units; LF/(LF + HF)
 nHF (%) HF power in normalized units; HF/(LF + HF)
 LF/HF Ratio of low to high frequency components; LF/HF
Photoplethysmogram signals
 PPG amplitude (V) Maximum amplitude in average PPG
 PPG systolic area (Vs) Area of systolic phase in average PPG
Respiration signals
 Respiration rate (bpm) Number of respirations per minute.
Impedance cardiography
 SV (ml) Stroke volume: volume of blood pumped from the left ventricle per beat
 CO (ml/min) Cardiac output: volume of blood being pumped from the heart per minute; stroke volume × heart rate
Combined variable from radial pressure pulse wave and electrocardiography
 PTT (ms) Time delay between the R-peak of the ECG and the peak of the RPPW