Ll. Watkins et al., NONINVASIVE ASSESSMENT OF BAROREFLEX CONTROL IN BORDERLINE HYPERTENSION - COMPARISON WITH THE PHENYLEPHRINE METHOD, Hypertension, 28(2), 1996, pp. 238-243
In this study, we examined the sensitivity of two recently developed n
oninvasive baroreflex measurement techniques to assess baroreflex cont
rol in hypertension. We assessed baroreflex sensitivity noninvasively
from covariations of systolic pressure and RR interval using spectral
analysis and sequence detection. The non-invasive estimates of baroref
lex control were compared with estimates derived from phenylephrine-in
duced increases in systolic pressure and RR interval in normotensive s
ubjects (n=27) and borderline hypertensive subjects (n=15). Baroreflex
sensitivity was significantly reduced in the borderline hypertensive
group relative to the normotensive group when assessed with the use of
either the non-invasive or invasive methods to index baroreflex contr
ol. In addition, estimates obtained from the non-invasive methods were
significantly correlated with baroreflex sensitivity assessed with th
e phenylephrine method (spectral: r=.48, P <.001; sequence: r=.50, P <
.001). These findings suggest that spectral analysis and the sequence
method provide viable alternatives to the pharmacological approach for
estimation of baroreflex sensitivity in hypertension.