TY - JOUR
T1 - Investigation of the effects of ischemic preconditioning on the HRV response to transient global ischemia using linear and nonlinear methods
AU - Moraru, L.
AU - Tong, S.
AU - Malhotra, A.
AU - Geocadin, R.
AU - Thakor, N.
AU - Bezerianos, A.
N1 - Funding Information:
This study was supported in part by the State Scholarships Foundation (S.S.F.) of Athens – Greece, who provided the financial support to L. M. and by NIH Grant R21NS42690. We gratefully acknowledge discussions with L. Cimponeriu.
PY - 2005/7
Y1 - 2005/7
N2 - Ischemic preconditioning (IP) has been used as a strategy to prevent cell death in various organs, including the brain and the heart. Investigation of the effects of ischemic preconditioning mostly employed models with reduced complexity, such as cell cultures, tissue slices or perfused organ preparations. Although such models can provide valuable insight into the protective mechanism of preconditioning, the functional (re)organization of the control mechanisms at the level of the living organism cannot be assessed. The purpose of the present animal model study was to evaluate the effect of global ischemic preconditioning on the heart rate variability (HRV) response to the asphyxia insult. The data consisted of 4 h RR interval measurements recorded in five preconditioned and five non-preconditioned Wistar rats. Using linear (time and frequency domain) and nonlinear (approximate entropy and parameters of Poincare plots) measures, we evaluated the dynamic time course of the HRV response to the asphyxia insult and the effect of preconditioning on the autonomic neurocardiac control. Both the linear and nonlinear parameters indicate a faster recovery of the baseline HRV corresponding to the preconditioned groups, though only the spectral analysis identifies a statistically significant difference between the two groups. For the preconditioned group, at about 90 min after the asphyxic insult, the autonomic neural balance (measured by LF/HF ratio) appears fully recovered. The small variation of the rest of the parameters indicates the necessity of further investigation including the design of a larger study with a higher statistical power. Our results show for the first time that global ischemic preconditioning influences the HRV response to the asphyxia injury. The neuroprotective effect of preconditioning translates into a faster recovery of the basal HRV and the autonomic modulation of the heart.
AB - Ischemic preconditioning (IP) has been used as a strategy to prevent cell death in various organs, including the brain and the heart. Investigation of the effects of ischemic preconditioning mostly employed models with reduced complexity, such as cell cultures, tissue slices or perfused organ preparations. Although such models can provide valuable insight into the protective mechanism of preconditioning, the functional (re)organization of the control mechanisms at the level of the living organism cannot be assessed. The purpose of the present animal model study was to evaluate the effect of global ischemic preconditioning on the heart rate variability (HRV) response to the asphyxia insult. The data consisted of 4 h RR interval measurements recorded in five preconditioned and five non-preconditioned Wistar rats. Using linear (time and frequency domain) and nonlinear (approximate entropy and parameters of Poincare plots) measures, we evaluated the dynamic time course of the HRV response to the asphyxia insult and the effect of preconditioning on the autonomic neurocardiac control. Both the linear and nonlinear parameters indicate a faster recovery of the baseline HRV corresponding to the preconditioned groups, though only the spectral analysis identifies a statistically significant difference between the two groups. For the preconditioned group, at about 90 min after the asphyxic insult, the autonomic neural balance (measured by LF/HF ratio) appears fully recovered. The small variation of the rest of the parameters indicates the necessity of further investigation including the design of a larger study with a higher statistical power. Our results show for the first time that global ischemic preconditioning influences the HRV response to the asphyxia injury. The neuroprotective effect of preconditioning translates into a faster recovery of the basal HRV and the autonomic modulation of the heart.
KW - Asphyxia
KW - Heart rate variability
KW - Preconditioning
KW - Transient global ischemia
UR - http://www.scopus.com/inward/record.url?scp=21244466638&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=21244466638&partnerID=8YFLogxK
U2 - 10.1016/j.medengphy.2004.12.005
DO - 10.1016/j.medengphy.2004.12.005
M3 - Article
C2 - 15990063
AN - SCOPUS:21244466638
SN - 1350-4533
VL - 27
SP - 465
EP - 473
JO - Medical Engineering and Physics
JF - Medical Engineering and Physics
IS - 6
ER -