The physiological activity of the heart is controlled and modulated mostly by the parasympathetic and sympathetic nervous systems. Heart rate variability (HRV) analysis is therefore used to observe fluctuations that reflect changes in the activity in these two branches. Knowing that acceleration and deceleration patterns in heart rate fluctuations are asymmetrically distributed, the ability to analyze heart rate variability asymmetry was introduced into MMA.
The new method is called Asymmetric Multiscale Multifractal Analysis (AMMA) and the analysis involved six groups: 61 healthy persons, 104 cases with aortic valve stenosis, 42 with hypertrophic cardiomyopathy, 36 with atrial fibrillation, 70 patients with coronary artery disease and 19 with congestive heart failure.
Analyzing the results obtained for the 6 groups of patients based on the AMMA method, i.e. comparing the Hurst surfaces for heart rate decelerations and accelerations, it was noticed that these surfaces differ significantly. And differences occur in most groups for large fluctuations (multifractal parameter q>0). In addition, a similarity was found for all groups for the AMMA Hurst surface for decelerations to the MMA Hurst surface – heart rate decelerations (lengthening of the RR intervals) appears to be the main factor determining the shape of the complete Hurst surface and so the multifractal properties of heart rate variability. The differences between the groups, especially for coronary artery disease, hypertrophic cardiomyopathy and aortic valve stenosis, are more visible if the Hurst surfaces are analyzed separately for accelerations and decelerations.
The AMMA results presented here may provide additional input for heart rate variability analysis and create a new paradigm for future medical screening. Note that the heart rate variability analysis using MMA (without distinguishing accelerations from decelerations) gave satisfactory screening statistics in our previous studies.

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