Time-Courses of the Central Frequencies of Low-Frequency Components of RR Intervals, Systolic and Diastolic Pressure Variabilities in Response to Active Orthostatic Test

• Published in: 2021 Computing in Cardiology (CinC) Vol. 48; pp. 1 - 4
• Main Authors: Carrasco-Sosa, Salvador, Guillen-Mandujano, Alejandra, Mejia-Rodriguez, Aldo R
• Format: Conference Proceeding
• Language: English
• Published: Creative Commons 13.09.2021
• Subjects: Cardiology; Correlation; Frequency estimation; Power capacitors; Resonant frequency; Surges; Time-frequency analysis
• ISSN: 2325-887X
• DOI: 10.23919/CinC53138.2021.9662730

In 25 healthy subjects we assessed the effects provoked by 1-min of active orthostatic test (AOT) on time-courses of central frequencies and powers of low frequency components ( CF LF, P LF) of RR ( CF LF RR , P LF RR ), systolic ( CF LF SP , P LF SP ) and diastolic ( CF LF DP , P LF DP ) pressures, estimated by a time-frequency distribution. Ensemble averages of the three P LF- CF LF pairs dynamics depicted an initial sudden change (ISC), followed by a recovery change (RC) and a final sudden change (FSC). The rapid changes were upwards for P LF and downwards for CF LF. Means of the maximal P LF surges and of minimal CF LF falls were greater and smaller ( p < 0.01 ) than their respective control means. Mean correlations of the three P LF- CF LF relations ranged from - 0.95+ 0.05\ to\ -0.97\pm 0.04 in ISC, -0.86\pm 0.13\ to\ -0.87\pm 0.15 in R C and -0.30\pm 0.59 to -0.41\pm 0.63 in FSC. In all stages, means of CF LF RR were greater ( p < 0.04 ) than those of CF LF DP . That the patterned responses of the three P LF- CF LF pairs time-courses present rapid initial and final changes, upstrokes for P LF and falls for CF LF, significantly inversely correlated, and the greater level of CF LF RR than CF LF DP , refine the time-course of cardiovascular sympathetic activation in AOT, possibly non-uniform, and suggest that CF LF are trustable quantitative sympathetic measures, with some specificity, CF LF RR for the cardiac and CF LF DP for the vasomotor one.