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Correlation between sonographic morphology and function of the cervical vagus nerves
Johann Otto Pelz1, Elena Belau1, Ina Menze1
1Department of Neurology, University Hospital Leipzig, Leipzig, Germany.
Abstract:
The heart receives parasympathetic and to a lesser degree sympathetic input via the vagus nerve. Here, we investigated whether morphological changes of the cervical vagus nerves (VN) as assessed by high-resolution ultrasound (HRUS) correlated with the autonomic cardiac innervation. Measurement of heart rate variability (HRV) and HRUS of the VNs were performed in 88 healthy subjects (50 female; mean age 56 ± 18 years). HRV parameters and the cross-sectional area (CSA) of the VNs correlated both inversely with age. We also found an inverse correlation between the left VN-CSA and HRV as well as parasympathetic parameters. The results imply an asymmetric parasympathetic (vagal) innervation of the heart.
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