Are Inter-Beat Intervals from Blood Pressure a Valid Alternative to R-R Intervals for the Multiscale Entropy Analysis of Heart Rate Variability?

Sampen was substantially overestimated while MSE HF and MSE LF were underestimated by ABP-derived IBI. The estimates closest to RRI were provided by d'PI (error +11% for SampEn, -2% for MSE HF ) and SSI (-2% for MSE LF ). Thus, the ABP-derived IBI series reflect SampEn components absent in RRI, being d'PI and SSI the closest surrogate for RRI.