Joanna Rymko
supervisor: Jan Żebrowski
According to the World Health Organization stroke is the third cause of death in the world. This disease is a neurological disorder resulting from a sudden cutoff of the blood supply to the brain. There are two types of this illness: ischemic stroke and hemorrhagic stroke. The main, published in scientific articles, studies of stroke refer to imaging methods such as computed tomography or magnetic resonance. Few researchers attempt to analyze the impact of stroke on other systems of the human body, e.g. cardiovascular regulation. This is an area that requires more research, because the knowledge of the association of stroke with heart rhythm variability is still small. I analyze heart rate variability, indicating changes in the cardiovascular system, in patients after ischemic stroke. I execute an analysis of measures of heart rhythm variability in the time and in the frequency domains and also apply nonlinear methods, such as: Poincaré plot, heart rate asymmetry measures - Guzik and Porta indexes, sample entropy, multiscale entropy and multiscale multifractal analysis. In my work, I study 24-hour electrocardiogram (ECG) recordings. ECG examination is definitely more common than computed tomography or magnetic resonance imaging, non-invasive and generating lower cost.