Abstract

RODRIGUEZ, Javier et al. Rev. acad. colomb. cienc. exact. fis. nat. [online]. 2011, vol.35, n.134, pp.5-12. ISSN 0370-3908.

The dynamical systems theory allows quantification of the state and evolution of dynamical systems. Summing fractal geometry, these theories have been useful to assess cardiac chaotic dynamic; developing clinical researches with acute myocardial infarction and, on the other side, finding through entropy law a diagnostic aid for clinical application, using the law of entropy. 150 Holters were selected: 50 diagnosed as normal, 50 with acute myocardial infarction based on conventional clinical diagnosis, and 50 diagnosed as different diseases. For each patient, the heart rate value sequence was generated, the attractor were built and the Box-Counting methodology was applied in a way to calculate the fractal dimension, comparing the occupation spaces. Finally, sensibility, specificity and Kappa coefficient on the physical-mathematical assessment was estimated for the patients with acute myocardial infarction and normal, compared to Gold-Standard. The attractors' fractal dimensions ranged between 1,4232 and 2,0000. The occupied spaces on the first grill (5 lat/min), applied on the 150 attractors ranged between 33 and 699; for the second one (10 lat/min), between 9 and 190. All acute myocardial infarction patients were out of normality values' patients; specificity and sensibility were 100% and the Kappa coefficient was 1. Cardiac chaotic attractors reveal a geometric order which quantifies dynamic through fractal's occupied spaces, differing patients with normality limits from those with acute disease; this could deduce the evolution between these states, making it useful to assess evolution in clinic.

Keywords : attractor; chaos; heart; Holter; diagnostic aid.

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