ABSTRACT
Often the heart activity is approximated to be periodic, and average rate is computed by taking the average of the time duration over a few samples. However, it is now well known that heart activity is not periodic and healthy heart requires continually changing time gap between successive heart beats. This chapter discusses the relationship of fractal properties of heart activity from the view of health and wellbeing. The ancient medicine from the east knew that it was not heart rate but the heart rate variability that was a good indicator of health. The Ayurvedic doctor or Chinese medicine practitioners study the steadiness of the change of the ‘pulse’ to identify disease. Modern medicine has discovered this phenomenon and HRV or heart rate variability is now routinely used to identify disease. Poincaré, named after Henri Poincaré, is a measure of self-similarity in an array, process or signal and Poincaré plots are being used for quantifying ECG recordings, specially the recordings taken over extended periods of time. Non-linear analysis of ECG that are based on its fractal properties have been found useful in quantifying the recordings and are becoming very useful, especially when considering recordings over extended periods of time.
