Heart rate variability ( HRV ) is an important indicator of health and disease, yet its physiological origins are poorly understood. The exact neural contributions to HRV are not well understood. In near-term fetal sheep, we aimed to identify fetal HRV measures reflecting the vagus nerve contributions to HRV. Fetal HRV was recorded during surgery and 72 hours later without (n=24) and with intra-surgical bilateral cervical vagotomy (n=15). We report the most encompassing set of fetal HRV measures known to-date and identify those HRV measures that are specific to the vagal modulation of HRV and show recovery dynamic due to fetal surgery. Our findings have clinical significance for in utero monitoring of fetal health during surgery. We provide a systematic delineation of vagal contributions to HRV across signal-analytical domains which should be relevant for the emerging field of bioelectronic medicine and the deciphering of the vagus code  .
Fetal heart rate variability ( fHRV ) is an important indicator of health and disease, yet its physiological origins , neural contributions in particular, are not well understood. We aimed to develop novel experimental and data analytical approaches to identify fHRV measures reflecting the vagus nerve contributions to fHRV. In near-term ovine fetuses, a comprehensive set of 46 fHRV measures was computed from fetal pre-cordial electrocardiogram recorded during surgery and 72 hours later without (n=24) and with intra-surgical bilateral cervical vagotomy (n=15). The fetal heart rate did not change due to vagotomy. We identify fHRV measures specific to the vagal modulation of fHRV: Multiscale time irreversibility asymmetry index (AsymI), Detrended fluctuation analysis (DFA) alpha1, Kullback-Leibler permutation entropy (KLPE) and Scale dependent Lyapunov exponent slope (SDLE alpha). We provide a systematic delineation of vagal contributions to fHRV across signal-analytical domains which should be relevant for the emerging field of bioelectronic medicine and the deciphering of the vagus code . Our findings also have clinical significance for in utero monitoring of fetal health during surgery .
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Heart
Fetal heart
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HRV
fHRV
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are poorly understood. The exact neural contributions to HRV
, neural contributions in particular,
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In near-term fetal sheep, we aimed to identify fetal HRV
We aimed to develop novel experimental and data analytical approaches to identify fHRV
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HRV. Fetal HRV was
fHRV. In near-term ovine fetuses, a comprehensive set of 46 fHRV measures was computed from fetal pre-cordial electrocardiogram
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We report the most encompassing set of fetal HRV measures known to-date and identify those HRV measures that are
The fetal heart rate did not change due to vagotomy. We identify fHRV measures
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HRV and show recovery dynamic due to fetal surgery. Our findings have clinical significance for in utero monitoring of fetal health during surgery.
fHRV: Multiscale time irreversibility asymmetry index (AsymI), Detrended fluctuation analysis (DFA) alpha1, Kullback-Leibler permutation entropy (KLPE) and Scale dependent Lyapunov exponent slope (SDLE alpha).
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HRV
fHRV
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. Our findings also have clinical significance for in utero monitoring of fetal health during surgery