OBJECTIVE:

To evaluate the cardiac dynamic for 18 hours through a mathematical law developed in the context of nonlinear systems theory and fractal geometry that originally evaluated the dynamics in 21 hours.

MATERIAL AND METHOD:

A retrospective study was done performing a mathematical induction with 8 normal and pathological continuous and ambulatory electrocardiographic records from January to December 2017. From each registry, values of heart rate frequency were taken to simulate a sequence for 18 hours to build the attractor of the cardiac dynamic. Then, the fractal dimension of the attractors as well as their occupation spaces were calculated to later apply parameters that differentiated between normal cardiac dynamics from the pathological ones. The same procedure was performed with 32 normal and pathological cardiac dynamics, determining its mathematical diagnosis in 18 hours, calculating its sensibility, specificity and Kappa coefficient.

RESULTS:

Subjects with normal chaotic dynamics were differentiated from the acute ones through occupation spaces calculated from the attractors evaluated with the mathematical law in 18 hours, which presented values in the Kp grid between 258 to 366 for normality and 43 to 195 for acute disease.

CONCLUSION:

The developed law allowed to diagnose in 18 hours even in cases where the abnormal cardiac dynamics presented no clinical manifestations.