Premium
Sympathetic and cardiovagal baroreflex sensitivity in humans: Comparison of Valsalva's maneuver and spontaneous methodologies
Author(s) -
Yang Huan,
Carter Jason R
Publication year - 2013
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.27.1_supplement.1117.4
Subject(s) - baroreflex , supine position , cardiology , heart rate , blood pressure , valsalva maneuver , diastole , anesthesia , medicine
Valsalva's maneuver (VM) and spontaneous techniques have been used to assess sympathetic (sBRS) and cardiovagal (cBRS) baroreflex sensitivity, but the intra‐individual reliability between these methodologies has not been examined. We hypothesized that spontaneous BRS would be positively correlated to VM BRS. Heart rate (HR), blood pressure (BP), and muscle sympathetic nerve activity (MSNA) were measured in 28 healthy subjects (age, 23±1 yr; 14 men, 14 women) during 10min supine rest and 3 VM at 40mmHg expiratory pressure (15s, 1min recovery). For spontaneous BRS, relations between diastolic BP and MSNA were used to determine sBRS, while relations between systolic BP and RR interval were used to determine cBRS. During VM, sBRS was the ratio of MSNA and the maximum diastolic BP reduction during early phase II, and cBRS was derived from linear relations between systolic BP and RR interval during early phase II (i.e. hypotensive stimulus) and phase IV (i.e. hypertensive stimulus). Spontaneous sBRS was significantly correlated to VM sBRS (r=0.516, p=0.036). Spontaneous cBRS (up‐up sequence) was correlated to VM phase IV cBRS (r=0.356, p=0.048). In contrast, spontaneous cBRS (down‐down sequence) was not correlated to VM phase II cBRS (r=0.128, p=0.295). In conclusion, our findings demonstrate low ‐to‐ moderate associations between spontaneous and VM estimates of sBRS and cBRS. Supported by NIH (HL‐ 098676).