Title
Validation of Sympathetic Activity Index From Heart Rate Variability series: A Preliminary Muscle Sympathetic Nerve Activity Study
Abstract
We recently proposed a Sympathetic Activity Index (SAI) through an orthonormal Laguerre expansion of linear RR-interval autoregressive kernels. The resulting heart rate variability (HRV) instantaneous indices may be used for the effective estimation of cardiac sympathetic outflow because the model is independent from the overlapping dynamics of the sympathetic and vagus nerves in the low frequency (LF) band (0.04-0.15Hz). In this study, we perform a preliminary validation of the SAI performance through concurrent estimates from efferent muscle sympathetic nerve activity (MSNA) recordings. ECG and MSNA were simultaneously recorded in 12 hypertensive patients during a 10min resting state in the supine position and up to 30min sodium nitroprusside (SNP, 0.4 μg/kg per minute) administration. Results show a characteristic increase of the MSNA during SNP intake with respect to the resting state (p<; 0.001). While SAI was associated with a significant increase during SNP (p<; 0.001), LF power did not show significant changes between sessions (p>0.05). Spearman analysis highlighted a significant correlation between SAI and MSNA (r=0.47; p<; 0.02) and a nonsignificant correlation between LF power and MSNA (r=-0.09; p>0.05). This study provides a further validation step of the SAI and supports the use of HRV parameters as a reliable proxy of cardiac sympathetic outflow dynamics.
Year
DOI
Venue
2020
10.22489/CinC.2020.365
2020 Computing in Cardiology
Keywords
DocType
ISSN
sympathetic activity index,heart rate variability series,preliminary muscle sympathetic nerve activity study,orthonormal Laguerre expansion,linear RR-interval autoregressive kernels,effective estimation,sympathetic nerves,vagus nerves,low frequency band,preliminary validation,SAI performance,efferent muscle sympathetic nerve activity recordings,MSNA,resting state,sodium nitroprusside,LF power,cardiac sympathetic outflow dynamics,heart rate variability instantaneous indices,time 10.0 min,frequency 0.04 Hz to 0.15 Hz
Conference
2325-8861
ISBN
Citations 
PageRank 
978-1-7281-1105-6
0
0.34
References 
Authors
0
6
Name
Order
Citations
PageRank
Gaetano Valenza100.34
Francesco Faita200.34
luca citi316827.88
J. P. Saul400.34
R. M. Bruno500.34
Riccardo Barbieri600.68