ENTROPY MEASURES OF HEART RATE VARIABILITY FOR SHORT ECG DATASETS IN PATIENTS WITH CONGESTIVE HEART FAILURE

We investigated the usefulness of entropy measures calculated for short ECG series in distinguishing healthy subjects from patients with congestive heart failure (CHF). Four entropy measures were tested: Approximate Entropy (ApEn), Sample Entropy (SampEn), Fuzzy Entropy (Fuzzy En) and Permutation Entropy (PE), each computed for ECG series of 1000, 500, 250 and 100 RR intervals. We found that with a reduction of the data set length up to 250 RR intervals, values of ApEn, SampEn, Fuzzy En and PE can remain significantly different in patients with CHF compared to healthy individuals. SampEn and Fuzzy En differentiated considered groups even for data sets of 100 RR intervals.