Spectral analysis, TRS, and sequence methods for estimating spontaneous baroreflex sensitivity yielded strongly related results, whereas weighted gain, X-AR, and Z methods exhibited lower agreement.
Observational (n=21)
Yes
How do different techniques for estimating spontaneous baroreflex sensitivity compare when applied to an identical dataset?
Different methods for estimating spontaneous baroreflex sensitivity yield varying results, highlighting the need to carefully consider algorithmic parameters and data handling.
This study compared spontaneous baroreflex sensitivity (BRS) estimates obtained from an identical set of data by 11 European centers using different methods and procedures. Noninvasive blood pressure (BP) and ECG recordings were obtained in 21 subjects, including 2 subjects with established baroreflex failure. Twenty-one estimates of BRS were obtained by methods including the two main techniques of BRS estimates, i.e., the spectral analysis (11 procedures) and the sequence method (7 procedures) but also one trigonometric regressive spectral analysis method (TRS), one exogenous model with autoregressive input method (X-AR), and one Z method. With subjects in a supine position, BRS estimates obtained with calculations of alpha-coefficient or gain of the transfer function in both the low-frequency band or high-frequency band, TRS, and sequence methods gave strongly related results. Conversely, weighted gain, X-AR, and Z exhibited lower agreement with all the other techniques. In addition, the use of mean BP instead of systolic BP in the sequence method decreased the relationships with the other estimates. Some procedures were unable to provide results when BRS estimates were expected to be very low in data sets (in patients with established baroreflex failure). The failure to provide BRS values was due to setting of algorithmic parameters too strictly. The discrepancies between procedures show that the choice of parameters and data handling should be considered before BRS estimation. These data are available on the web site (http://www.cbi.polimi.it/glossary/eurobavar.html) to allow the comparison of new techniques with this set of results.
Laude et al. (2004) conducted an observational in Baroreflex failure (n=21). Spontaneous baroreflex sensitivity estimation techniques was evaluated on Agreement among spontaneous baroreflex sensitivity estimates. Spectral analysis, TRS, and sequence methods for estimating spontaneous baroreflex sensitivity yielded strongly related results, whereas weighted gain, X-AR, and Z methods exhibited lower agreement.