Hemispheric influence on autonomic modulation and baroreflex sensitivity

• Published in: Annals of neurology Vol. 49; no. 5; pp. 575 - 584
• Main Authors: Hilz, Max J., Dütsch, Matthias, Perrine, Ken, Nelson, Peter K., Rauhut, Ute, Devinsky, Orrin
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 01.05.2001; Willey-Liss
• Subjects: Adult; Analysis of Variance; Autonomic Nervous System - physiopathology; Baroreflex - physiology; Biological and medical sciences; Blood Pressure - physiology; Brain - physiopathology; Epilepsy - physiopathology; Female; Functional Laterality - physiology; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Heart Rate - physiology; Humans; Male; Medical sciences; Middle Aged; Nervous system (semeiology, syndromes); Neurology; Human; Nervous system diseases; Cardiovascular control; Epilepsy; Sympathetic nervous system; Cerebral disorder; Sensitivity; Hemisphere dominance; Cerebral hemisphere; Autonomic nervous system; Baroreflex; Central nervous system disease; Laterality; Parasympathetic nervous system
• ISSN: 0364-5134; 1531-8249
• DOI: 10.1002/ana.1006

Several studies suggest hemispheric lateralization of autonomic cardiovascular control. There is controversy regarding which hemisphere dominates sympathetic or parasympathetic activity. Hemispheric influences on baroreflex sensitivity (BRS) have not yet been evaluated. To determine hemispheric autonomic control in epilepsy patients, we assessed cardiovascular and baroreflex modulation before and during hemispheric inactivation. For 15 patients with drug‐refractory epilepsy, we analyzed autonomic heart rate (HR) and blood pressure (BP) modulation and BRS before and during left and right intracarotid amobarbital procedure (IAP). After Blackman‐Tukey spectral analysis, we calculated the low‐frequency (LF: 0.04–0.15 Hz) and high‐frequency (HF: 0.15–0.5 Hz) power of HR and BP as well as BRS as the LF transfer function gain between BP and HR. Right hemispheric inactivation induced a significant decrease of BP and an increase of HF power of HR and BP (p < 0.05). Left inactivation increased HR, BP, and LF power of both signals and decreased BRS by nearly 30% (p < 0.05). The results confirm previous IAP studies showing sympathetic lateralization in the right hemisphere and, moreover, demonstrate parasympathetic predominance and up‐regulation of BRS in the left hemisphere. In epilepsy patients, unilateral electrical activity might derange autonomic balance between both hemispheres and contribute to cardiovascular dysregulation and sudden fatalities.