Measures of cardiovascular autonomic regulation derived from spontaneous methods and the Valsalva maneuver. Export

@article{citeulike:3981467, abstract = {The response of heart rate to a given change of systolic blood pressure is a fundamental characteristic of the cardiovascular system. The assessment of baroreflex gain (BRS) as an index of baroreflex function is based on the quantification of RR interval changes related to blood pressure changes. The spontaneous sequence and cross spectral methods describe baroreflex gain derived from spontaneous fluctuations of these parameters, yielding the up sequence and down sequence BRS and the alfa index. Phase IV of the Valsalva maneuver is also used to calculate cardiac vagal baroreflex gain. In this study, we compared the two spontaneous methods and the Valsalva maneuver in assessing baroreflex gain in 56 healthy volunteers. The BRS values calculated from different methods were as follows: up sequence BRS 12 +/- 8.6 ms/mm Hg, down sequence BRS 10 +/- 6.1 ms/mm Hg, low frequency alfa index 12.1 +/- 8.2 ms/mm Hg, Valsalva BRS 9.7 +/- 7.2 ms/mm Hg. We found close relationship between baroreflex gain derived from up and down sequences (R = 0.91, p < 0.001), down sequence BRS and low frequency alfa index (R = 0.81, p < 0.001); significant correlation between up sequence BRS and low frequency alfa index (R = 0.65, p < 0.001), the Valsalva-derived BRS and down sequence BRS (R = 0.37, p = 0.043), but no correlation between the Valsalva BRS and up sequence BRS, the Valsalva BRS and low frequency alfa index. BRS values calculated by different methods decreased with increasing age. There was no influence of age on mean arterial blood pressure elevation in late phase II of the Valsalva maneuver, nor any indication that the Valsalva BRS was related to the MAP changes. We concluded that all of these methods are useful in calculating baroreflex gain, but owing to the differences in underlying physiological mechanisms, they are not necessarily in correlation with each other.}, author = {Z\"{o}llei, E. and Paprika, D. and Rudas, L.}, citeulike-article-id = {3981467}, citeulike-linkout-0 = {http://view.ncbi.nlm.nih.gov/pubmed/12531403}, citeulike-linkout-1 = {http://www.hubmed.org/display.cgi?uids=12531403}, comment = {Different techniques (spontaneous sequence method, cross spectral method, Phase IV of the Valsalva maneuver) yield useful estimates of BRS (baroreflex gain) but do not all correlate completetly with each other because of different underlying physiological mechanisms}, day = {31}, issn = {1566-0702}, journal = {Autonomic neuroscience : basic \& clinical}, keywords = {autonomic, baroreflex, diagnosis, physiology, sensitivity}, month = {January}, number = {1-2}, pages = {100--105}, posted-at = {2009-01-30 11:57:13}, priority = {2}, title = {Measures of cardiovascular autonomic regulation derived from spontaneous methods and the Valsalva maneuver.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/12531403}, volume = {103}, year = {2003} }

TY - JOUR ID - citeulike:3981467 L3 - citeulike-article-id:3981467 N2 - The response of heart rate to a given change of systolic blood pressure is a fundamental characteristic of the cardiovascular system. The assessment of baroreflex gain (BRS) as an index of baroreflex function is based on the quantification of RR interval changes related to blood pressure changes. The spontaneous sequence and cross spectral methods describe baroreflex gain derived from spontaneous fluctuations of these parameters, yielding the up sequence and down sequence BRS and the alfa index. Phase IV of the Valsalva maneuver is also used to calculate cardiac vagal baroreflex gain. In this study, we compared the two spontaneous methods and the Valsalva maneuver in assessing baroreflex gain in 56 healthy volunteers. The BRS values calculated from different methods were as follows: up sequence BRS 12 +/- 8.6 ms/mm Hg, down sequence BRS 10 +/- 6.1 ms/mm Hg, low frequency alfa index 12.1 +/- 8.2 ms/mm Hg, Valsalva BRS 9.7 +/- 7.2 ms/mm Hg. We found close relationship between baroreflex gain derived from up and down sequences (R = 0.91, p < 0.001), down sequence BRS and low frequency alfa index (R = 0.81, p < 0.001); significant correlation between up sequence BRS and low frequency alfa index (R = 0.65, p < 0.001), the Valsalva-derived BRS and down sequence BRS (R = 0.37, p = 0.043), but no correlation between the Valsalva BRS and up sequence BRS, the Valsalva BRS and low frequency alfa index. BRS values calculated by different methods decreased with increasing age. There was no influence of age on mean arterial blood pressure elevation in late phase II of the Valsalva maneuver, nor any indication that the Valsalva BRS was related to the MAP changes. We concluded that all of these methods are useful in calculating baroreflex gain, but owing to the differences in underlying physiological mechanisms, they are not necessarily in correlation with each other. IS - 1-2 JF - Autonomic neuroscience : basic & clinical SN - 1566-0702 EP - 105 TI - Measures of cardiovascular autonomic regulation derived from spontaneous methods and the Valsalva maneuver. VL - 103 SP - 100 KW - autonomic KW - baroreflex KW - diagnosis KW - physiology KW - sensitivity N1 - Different techniques (spontaneous sequence method, cross spectral method, Phase IV of the Valsalva maneuver) yield useful estimates of BRS (baroreflex gain) but do not all correlate completetly with each other because of different underlying physiological mechanisms AU - Zöllei, E AU - Paprika, D AU - Rudas, L PY - 2003/01/31/ UR - http://view.ncbi.nlm.nih.gov/pubmed/12531403 ER -