BRS analysis from baroreflex sequences and baroreflex events compared using spontaneous and drug induced data

Spontaneous time domain BRS estimation is based on the SBP-RR slope, which can be computed from either baroreflex sequences (BS) or baroreflex events (BE). BRS analysis from BEs was recently shown be advantageous particularly in the cases of reduced BRS or when BS are not identified. Also, it offers a superior discrimination between lying and standing positions. In this work, the methods developed for spontaneous BRS analysis are further compared using spontaneous and drug induced data. The results corroborate that spontaneous and drug induced estimates are different although correlated. In particular, if BEs are used the differences and the correlation between the estimates is higher. No precision improvement is achieved if the BRS is estimated from drug induced data. In spontaneous, the higher number of beats in BEs in comparison with BSs (at the expense of a lower SBP-RR correlation) allows a higher BRS estimate precision using recordings of the same length.