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Heart Rate Variability (HRV) Analysis Software

HRV epoch analysis

AcqKnowledge® includes a series of automated Heart Rate Variability (HRV) analysis tools that conform to international cardiology standards.  It is possible to perform the analysis over user defined selections of data, or automatically within user specified time periods, or between stimulus presentation event marks, or user entered event marks. The user can also create focus areas in realtime or post-acquisition and the software will analyze the data within areas.

Options for:

Single-epoch HRV – Spectral
Single-epoch HRV is the examination of a user defined area of data.

Multi-epoch HRV – Statistical
This analysis computes statistical measures of heart rate variability in user-specified time intervals These measures (RMSSD, SDSD, and pNN50) can be extracted by fixed time intervals, time between event boundaries or focus areas.

Multi-epoch HRV and RSA – Spectral
This routine performs RSA and HRV analyses on specified time slices along an ECG waveform, whether by markers, fixed time intervals or focus areas.

R-R Poincare Plot
Poincare plots are constructed from ECG Lead II data. A Poincare plot is an XY plot with RR intervals in seconds on one axis and on the other axis the sequence delayed by one beat (RR vs. RR+1).

RSA – Time-series
This partcular method looks at the time domain data and uses the peak and valley method to compute Respirator Sinus Arrhythmia. It is used to explore the connection between respiration and changes to heart rate. Variations in the heart rate can be directly correlated with vagal tone. The RSA index can be used to investigate changes in this connection during recording.

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AcqKnowledge® software includes a fully-automated Heart Rate Variability analysis tool. The algorithm conforms to the frequency domain algorithm guidelines as published by the European Heart Journal. For optimal results, follow these suggestions for Preparing HRV Data for Analysis.

  • There are two methods for extracting the RR intervals from the ECG signal:
    • A modified Pan-Tompkins QRS detector
    • Events located in the file – ECG QRS Peak event

HRV interpolated tachogram

  • The RR intervals are re-sampled to a continuous sampling rate in order to extract frequency information.
    • Cubic-spline interpolation is used to generate this continuous time-domain representation of the RR intervals.

HRV Analysis PSD data

  • The frequency information is extracted from the RR intervals and analyzed to produce standard ratios. Power sums are reported in units of sec2/Hz. A Welch periodogram is used to generate the Power Spectral Density (equivalent to Transform > Power Spectral Density).

 HRV Analysis Poincare Plot

  • The software reports values for the typical HRV frequency bands, including: Very Low Frequency, Low Frequency, High Frequency, and Very High Frequency ranges. The analysis also includes values for the overall ratios: Sympathetic, Vagal and Sympathetic – Vagal balance. The ratio values and frequency band results can be plotted into a Journal file or exported for further analysis.

HRV epoch analysis

AcqKnowledge also inlcudes a Poincare plot option that will display either selected areas of the data, or the entire file. The Poincare plot is an X/Y plot of the RR intervals in seconds. One axis displays the RR interval and the other axis displays the interval delayed by one beat.

HRV Analysis Poincare Plot


Note: The BioHarness is not recommended for heart rate variability studies because the sample rate used to record the ECG waveform is at the very low end of the optimal range for HRV studies.



Application Notes

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Hardware Packages   |   Heart Rate Variability (HRV) Analysis Software

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