The principle difficulty with the analysis of the heart rate variability (HRV) is that heart rate dynamics are non-linear and non-stationary. Detrended fluctuation analysis (DFA) and correlation dimension (CD) are non-linear HRV measures to quantify fractal-like autocorrelation properties and to characterize the complex behaviour of nonlinear time series. Optimal ECG sampling rate is an important issue for accurate quantification of HRV. High ECG sampling rate results in very high processing time and low sampling rate produces signal quality degradation results in clinically misinterpreted HRV. In this work the impact of ECG sampling frequency on non-linear HRV have been quantified in terms of short-range & long-range DFA and CD on short-term (N=200), medium-term (N=500) and long-term (N=1000) data. Non-linear HRV parameters are found to be sensitive to ECG sampling frequency and effect of sampling frequency will be a function of data length.

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Ecg Hrv Sampling Frequency Dfa Cd Signal Processing.