Formation of complex discrete samples for electrocardiogram isoline drift extraction devices

Abstract

In the automatic analysis of an electrocardiosignal, in order to adequately assess its amplitude parameters, it is necessary to ensure that there is no isoline drift in the signal. The direct removal of the isoline drift using a high-pass filter leads to distortion of the shape and amplitude parameters of the electrocardiosignal elements. When extracting the isoline drift based on interpolation of samples on the PQ segment, the frequency of the extracted isoline drift signal cannot even theoretically exceed half the heart rate, but in reality it is an order of magnitude less. The purpose is to develop a device for the formation of complex discrete samples of the electrocardiosignal, ensuring the isolation without loss of informative components of the electrocardiosignal of the isoline drift with a frequency range comparable to the heart rate, in conditions of variability of the sampling frequency due to heart rate variability. The possibility of expanding the frequency range of the isoline drift signal isolated from the electrocardiosignal based on the real-time transformation of isoline drift samples taken at the TP interval into complex discrete samples has been substantiated. When forming complex discrete samples, the variability of the sampling period due to heart rate variability is taken into account. A device for forming complex discrete samples of the isoline drift signal has been proposed, allowing extraction of isoline drift with an extended frequency range without loss the informative components of the electrocardiosignal. The developed device can be used both directly as part of mobile electrocardiographs designed to monitor a person's ECG in the conditions of his daily activities, and in equipment for processing daily electrocardiograms before analyzing their parameters.