Reduced heart rate variability and lower cerebral blood flow associated with poor cognition during recovery following concussion.

Reduced heart rate variability and lower cerebral blood flow associated with poor cognition during recovery following concussion. Auton Neurosci. 2019 Sep;220:102548 Authors: Purkayastha S, Williams B, Murphy M, Lyng S, Sabo T, Bell KR Abstract Although physiological deficits such as altered cerebral blood flow (CBF), and autonomic nervous system (ANS) dysregulation have been reported following a concussion, the relationship between CBF and ANS with functional outcome post-injury remains unclear. Our present study was designed to examine heart-rate variability (HRV) using percentage of successive NN intervals (pNN50) and CBF on day-3 (T1), day-21 (T2), and day-90 (T3) following a concussion in collegiate athletes (N = 31) in comparison to non-injured controls (N = 31). Continuous RR-interval (3-lead electrocardiogram), middle cerebral artery blood velocity (MCAV; transcranial Doppler ultrasonography), mean arterial pressure (MAP; finger photoplethysmography) were obtained at rest. Cerebrovascular conductance index (CVCi) was estimated as a ratio of MCAV to MAP. Cognition was evaluated with standard assessment of concussion (SAC), and Trails A & B. Compared to the controls, lower HRV (43 ± 15 vs. 27 ± 20%; p < 0.0001) was observed at T1 with normalization at T2 and T3. No difference in MCAV between the control and the concussed groups across the three time points were observed. However, post-hoc analyses i...
Source: Autonomic Neuroscience - Category: Neuroscience Authors: Tags: Auton Neurosci Source Type: research