TY - JOUR
T1 - Circadian and ultradian rhythms in heart rate variability
AU - Stein, Phyllis K.
AU - Domitrovich, Peter P.
AU - Lundequam, Eric J.
AU - Duntley, Stephen P.
AU - Freedland, Kenneth E.
AU - Carney, Robert M.
N1 - Funding Information:
This research was supported in part by RO1 HL065356 from the National Heart Lung and Blood Institute, USA.
PY - 2006/10/1
Y1 - 2006/10/1
N2 - Aim: Heart rate variability (HRV) patterns reflect the changing effect of sympathetic and parasympathetic modulation of the autonomic nervous system. While overall and circadian heart rate (HR) and HRV are well characterized by traditional measures, there is currently no method to measure ultradian cycles of HR and HRV. Materials and methods: HR/HRV for each 2-min interval was calculated using normal-to-normal interbeat intervals from overnight polysomnographic ECGs in 113 subjects, aged 58±10 years (65 male, 48 female). HR, SDNN2, high-frequency power (HF) and the LF (low-frequency power)/HF ratio were plotted. A curve-fitting algorithm, developed in MatLab, identified cyclic patterns of HR/HRV and extracted parameters to characterize them. Results were compared for older vs. younger patients, males vs. females, with vs. without severe sleep apnea, and for the upper and lower half of sleep efficiency. Results: Ultradian patterns for different HR/HRV indices had variable correspondences with each other and none could be considered surrogates. Differences were seen for all comparison groups, but no one marker was consistently different across comparisons. Conclusion: Each HR/HRV parameter has its own rhythm, and the correspondence between these rhythms varies greatly across subjects. Quantification of ultradian patterns of HRV is feasible and could provide new insights into autonomic physiology.
AB - Aim: Heart rate variability (HRV) patterns reflect the changing effect of sympathetic and parasympathetic modulation of the autonomic nervous system. While overall and circadian heart rate (HR) and HRV are well characterized by traditional measures, there is currently no method to measure ultradian cycles of HR and HRV. Materials and methods: HR/HRV for each 2-min interval was calculated using normal-to-normal interbeat intervals from overnight polysomnographic ECGs in 113 subjects, aged 58±10 years (65 male, 48 female). HR, SDNN2, high-frequency power (HF) and the LF (low-frequency power)/HF ratio were plotted. A curve-fitting algorithm, developed in MatLab, identified cyclic patterns of HR/HRV and extracted parameters to characterize them. Results were compared for older vs. younger patients, males vs. females, with vs. without severe sleep apnea, and for the upper and lower half of sleep efficiency. Results: Ultradian patterns for different HR/HRV indices had variable correspondences with each other and none could be considered surrogates. Differences were seen for all comparison groups, but no one marker was consistently different across comparisons. Conclusion: Each HR/HRV parameter has its own rhythm, and the correspondence between these rhythms varies greatly across subjects. Quantification of ultradian patterns of HRV is feasible and could provide new insights into autonomic physiology.
KW - Heart rate
KW - Heart rate variability
KW - Ultradian rhythms
UR - http://www.scopus.com/inward/record.url?scp=34247273044&partnerID=8YFLogxK
U2 - 10.1515/BMT.2006.026
DO - 10.1515/BMT.2006.026
M3 - Article
C2 - 17061928
AN - SCOPUS:34247273044
VL - 51
SP - 155
EP - 158
JO - Biomedizinische Technik
JF - Biomedizinische Technik
SN - 0013-5585
IS - 4
ER -