TY - JOUR
T1 - Frequency domain assessment of the coupling strength between ventricular repolarization duration and heart period during graded head-up tilt
AU - Porta, Alberto
AU - Bari, Vlasta
AU - Badilini, Fabio
AU - Tobaldini, Eleonora
AU - Gnecchi-Ruscone, Tomaso
AU - Montano, Nicola
PY - 2011/11
Y1 - 2011/11
N2 - We test the hypothesis that the degree of correlation between ventricular repolarization duration (VRD) and heart period (HP) carries information on cardiac autonomic regulation. The degree of correlation was assessed in the frequency domain using squared coherence function during an experimental protocol known to gradually induce a shift of sympathovagal balance toward sympathetic predominance (ie, graded head-up tilt). We observed a progressive decrease of squared coherence with tilt table inclination, thus confirming the working hypothesis. The VRD-HP uncoupling occurs in the high-frequency band, centered on the respiratory rate, thus suggesting that vagal withdrawal is responsible for the VRD-HP uncoupling.
AB - We test the hypothesis that the degree of correlation between ventricular repolarization duration (VRD) and heart period (HP) carries information on cardiac autonomic regulation. The degree of correlation was assessed in the frequency domain using squared coherence function during an experimental protocol known to gradually induce a shift of sympathovagal balance toward sympathetic predominance (ie, graded head-up tilt). We observed a progressive decrease of squared coherence with tilt table inclination, thus confirming the working hypothesis. The VRD-HP uncoupling occurs in the high-frequency band, centered on the respiratory rate, thus suggesting that vagal withdrawal is responsible for the VRD-HP uncoupling.
KW - Autonomic nervous system
KW - Head-up tilt
KW - Heart rate variability
KW - QT variability
KW - QT-R-R relation
UR - http://www.scopus.com/inward/record.url?scp=80054902359&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80054902359&partnerID=8YFLogxK
U2 - 10.1016/j.jelectrocard.2011.08.002
DO - 10.1016/j.jelectrocard.2011.08.002
M3 - Article
C2 - 21908003
AN - SCOPUS:80054902359
VL - 44
SP - 662
EP - 668
JO - Journal of Electrocardiology
JF - Journal of Electrocardiology
SN - 0022-0736
IS - 6
ER -