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Updated: Mar 28, 2026

Autonomic Function Following Concussion in Youth Athletes: An Exploration of Heart Rate Variability Using 24-hour Recording Methodology
Published on: September 21, 2018
Abstract:
Syncope is an abrupt loss of consciousness and postural tone frequently due to disturbance of the normal autonomic nervous system reflexive mechanisms in regulating peripheral vascular resistance, blood pressure, and heart rate. This leads to a transient decrease in cerebral blood flow. It is a common presenting complaint in children and adolescents. In many cases, there is a characteristic preceding prodrome of dizziness, nausea, diaphoresis, and pallor. Although most cases of syncope are benign in etiology, it frequently causes stress and anxiety in regard to potential cardiovascular disease and possible sudden cardiac death. With careful screening by detailed patient history, comprehensive physical examination, and electrocardiogram (ECG), a significant majority of patients with serious underlying cardiac conditions will be identified. The routine use of echocardiography, ambulatory ECG, tilt-table tests, and exercise stress tests is expensive and frequently of low diagnostic yield. With benign forms of syncope, patient reassurance and education should be the first-line treatment.
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