Heart rate asymmetry in aortic valve stenosis patients

Heart rate asymmetry is one of the measure of the autonomic nervous system activity. Here we use the Phase Rectified Signal Averaging method for heart rate asymmetry calculations and focus on Deceleration Capacity (DC) obtained for aortic valve stenosis patients just before surgical replacement of the aortic valve. In the study we used 6-h nighttime data from 107 patients aged 60-71 y. We compare the results between male and female groups obtaining a larger diversity in males. Unfortunately, the decrease of the DC parameter, which is used as mortality risk marker in other several regulatory dysfunctions is not applicable for aortic stenosis in risk stratification. We did not observe distinction of patients who died earlier than one year after surgery. In spite of this, we introduce the modified nDC and Acceleration Capacity (nAC) parameters for a better assessment of the ability to lengthen and shorten RR intervals.