Temporal asymmetries across several heartbeats in the heart period and blood pressure series show gender differences

The series of heart periods and blood pressure show temporal asymmetries when analyzing beat-to-beat changes. Here, we quantify temporal asymmetries by runs of accelerations and decelerations in the heart period series and runs of increases and reductions in the blood pressure series. Furthermore, gender differences in the asymmetries are investigated. RR tachograms, interbeat intervals (IBI) from the blood pressure series and the systolic blood pressure series (BP ${ }_{\text {syst }}$) from 276 healthy subjects in the supine position (147 female, median age 24 years, 28 min. recording) were analyzed. Temporal asymmetries were quantified on a beat-to-beat basis. Asymmetries appeared in the RR interval, IBI and $B_{\text {syst. }}$ series. Gender differences could be detected except for $B_{\text {syst. }}$ The shape parameter of the Weibull distribution of cumulative accelerations differed from cumulative decelerations in RR, IBI and $\mathrm{BP}_{\text {syst }}$ indicating asymmetries across several heartbeats. Gender differences indicated that asymmetries across several heartbeats are different in men and women.