Wavelet Analysis of Photoplethysmogram in Zebrafish Larvaе Cardiovascular System Study

The work is aimed on the development of advanced algorithms for analyzing the photoplethysmogram signal, which characterizes cardiac activity. We have designed an algorithm that separates individual pulse waveforms from the photoplethysmogram, even in the presence of artifacts caused by pathological changes in zebrafish cardiac activity, due to cadmium exposure. The proposed algorithm is based on digital image processing and discrete wavelet transform; it enables reliable separation of individual pulse waveforms. The data obtained can then be processed using conventional techniques, providing accurate pulse wave characteristics for various applications, including toxicology studies, drug development and developmental biology research.

I. Introduction

Danio rerio (zebrafish) is a well-known model organism. Numerous studies have revealed that individuals of this species exhibit genetic similarities to humans, making them an excellent candidate for conducting experiments that would be difficult or impossible to perform on humans [1]. Photoplethysmography is a non-invasive technique used to measure changes in blood volume in vessels. The photoplethysmogram (PPG), which is acquired using this method, is a periodic signal that is modulated by heart muscle activity [2]. PPG consists of individual pulse waves, with the classic shape shown in Fig. 1. The study of individual parameters of pulse waveforms is used in human physiology research, as it offers a more comprehensive insight into the human cardiovascular system, in addition to heart rate [4].