This software package makes available both methods commonly used for BRS, the Sequence Method and the Spectral Method. It consists of two software modules:
Nevrokard™ SA-BRS is a software package for Baroreflex
Sensitivity Analysis in small animals.
It features frequency domain
analysis of up to 5Hz and a resampling rate of 10Hz. It is intended
for use in animals having a considerably higher heart rate than
human subjects. The complementary File Preparation software for
small animals is Nevrokard™ SA-BRSFP software.
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Detection of R waves, calculation of RR intervals, editing of the ECG record. |
Determination of systolic (SBP) and diastolic BP (DBP), calculation of mean BP (MBP), graphic display of BP, elimination of servo components by automatic interpolation. |
Different file manipulations, zooming parts of the file, selection of RRI or HR basis, on-screen measurements of time domain parameters etc. are possible. |
Full time-domain STATISTICS is available (for RRI, HR, SBP, MBP and DBP): Max., Min., Max./Min., Range, Mean of NN, Mean of dNN (MSD), Median, 95% Conf. Interval, 99% Conf. Interval, Coef. of Variance, Variance, Std. Deviation (SDNN), Std. Error (SENN), SDSD, RMSSD |
Sequence Method of BRS |
The software calculates the BRS Index for +BP/+PI, -BP/-PI, All Seq. with RRI selected as the basis of calculations and for +BP/-HR, -BP/+HR, All Seq. with HR selected as the basis of calculations (below left), as well for all three pressures (systolic, mean, diastolic). All BRS results are displayed in a single Results Table (below right). |
In order to be included in the BRS estimate, each identified sequence must fulfill five criteria defined by the user: 1. minimal RRI change (range 0-10 ms) or minimal HR change (range 0.001-9.999 bpm); 2. minimal BP change (range 0-10 mmHg); 3. minimal number of beats in the sequence (range 3-5 beats); 4. minimal correlation coefficient (range 0-1 in steps of 0.05); 5. Lag (Delay) between SBP and RRI (range 0-14 beats). |
Spectral Method of BRS |
FFT spectra of RRI and BP, cross spectrum and coherence are calculated and displayed (below). Results are given as LF/HF ratios for RRI and BP, as well as in the form of alpha-indices for LF and HF. |
Area limits and coherence settings can be adjusted by the user (below). The frequency limits may be fixed (set in advance) or automatically defined by the result of the coherence calculation. |
RESULTS OF ANALYSIS |
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