Neurohormonal response to head-up tilt and its role in vasovagal syncope

• Published in: The American journal of cardiology Vol. 79; no. 9; pp. 1302 - 1306
• Main Authors: JARDINE, D. L, MELTON, I. C, CROZIER, I. G, BENNETT, S. I, DONALD, R. A, IKRAM, H
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier 01-05-1997; Elsevier Limited
• Subjects: Adrenocorticotropic Hormone - blood; Analysis of Variance; Arginine Vasopressin - blood; Biological and medical sciences; Body Surface Area; Cardiovascular disease; Cranial nerves. Spinal roots. Peripheral nerves. Autonomic nervous system. Gustation. Olfaction; Forearm - blood supply; Heart; Hemodynamics - physiology; Hormones; Hormones - blood; Humans; Medical sciences; Middle Aged; Nervous system (semeiology, syndromes); Neurology; Posture - physiology; Regional Blood Flow - physiology; Space life sciences; Syncope, Vasovagal - physiopathology; Tilt-Table Test; Epinephrine; Human; Head position; Nervous system diseases; 8-Arginine vasopressin; Consciousness impairment; ACTH; Exploration; Vasovagal syncope; Test; Diseases of the autonomic nervous system; Norepinephrine; Hemodynamics; Neurological disorder; Tilt up method
• ISSN: 0002-9149; 1879-1913
• DOI: 10.1016/S0002-9149(9X)00084-9

In a controlled study, 26 patients with a history of recurrent syncope were found to have increased arginine vasopressin, corticotrophin, and atrial natriuretic factor levels after 5 minutes of 60 degrees head-up tilt, long before they became hypotensive. The exaggerated neurohormonal response in these patients may indicate a greater sensitivity to central hypovolemia which may predispose to vasovagal syncope, mediated by the vasodilatory effects of atrial natriuretic factor or the sensitization of mechanoreceptors by arginine vasopressin.