Abstract

Aim: to confirm the diagnostic capacity in 18 hours of a methodology applied to heart dynamics in the frame of a chaotic exponential mathematical law previously applied in 21 hours based on dynamical systems theory and fractal geometry. Materials and methods: a blind study was developed with 100 Holter registries, 30 normal and 70 pathological, with lengths of at least 18 hours up to 21 hours. The values of heartbeats, as well as minimal and maximal heart rates, were taken to build attractors and quantify their fractal dimension and its occupation space with the Box-Counting method. A comparison between the values obtained for both 18 and 21 hours was made as well as a comparison with the clinical diagnostic Gold Standard. Results: the values obtained for the spaces of occupation in the grid Kp of 18 hours were between 202 and 374 and between 43 to 195 for the pathological ones. Sensitivity and specificity were 100% and the Kappa coefficient was 1 for 18 and 21 hours. Conclusion: the diagnostic capacity of a chaotic exponential mathematical law applied to Holter registries in 18 hours was confirmed. This reduction can be useful in order to obtain earlier diagnostics about heart dynamics in contexts such as in the Intensive Care Unit.

Keywords

Nonlinear dynamics, Heart rate, Diagnostic