Abstract | OBJECTIVES: The purpose of this study was to review the results of investigation and management of children with syncope and a structurally normal heart. BACKGROUND:
Syncope is a common clinical problem and has many etiologies. Autonomic testing and, in particular, the tilt/orthostatic test have helped to positively diagnose neurocardiogenic syncope in a high proportion of such patients. METHODS: RESULTS: The orthostatic test was positive for neurocardiogenic syncope in 100 patients (62%) and negative in 62 (38%). Patients in the former group were older, were more often female and had a diminished response to carotid sinus massage, a higher Valsalva ratio and a higher supine epinephrine level. Both groups showed an increase in epinephrine and norepinephrine levels at 5 min of standing. In the orthostatic positive group at the time of syncope, norepinephrine levels decreased, whereas epinephrine levels increased. Patients in this group were also more sensitive to the vasodilating effect of isoproterenol but not to its chronotropic effects. Eleven patients had cardioinhibitory syncope ( asystole > or = 3 s). Of these, three had pacemaker implantation. Fludrocortisone and salt used in 84 patients in the orthostatic positive group produced resolution of symptoms in 55 patients (65%) and improvement in 14 (17%). Ten patients received beta-blockers, with resolution in four and improvement in four. CONCLUSIONS: Patients with orthostatic test-proved neurocardiogenic syncope show evidence of autonomic dysfunction. They also show beta- adrenergic hypersensitivity. Treatment initiated on the basis of the protocol was associated with amelioration of symptoms in the majority of patients.
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Authors | S Balaji, P C Oslizlok, M C Allen, C A McKay, P C Gillette |
Journal | Journal of the American College of Cardiology
(J Am Coll Cardiol)
Vol. 23
Issue 3
Pg. 779-85
(Mar 01 1994)
ISSN: 0735-1097 [Print] United States |
PMID | 7906701
(Publication Type: Journal Article)
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Chemical References |
- Adrenergic beta-Antagonists
- Receptors, Adrenergic, beta
- Sodium Chloride
- Fludrocortisone
- Norepinephrine
- Epinephrine
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Topics |
- Adrenergic beta-Antagonists
(therapeutic use)
- Autonomic Nervous System
(physiopathology)
- Autonomic Nervous System Diseases
(complications, diagnosis)
- Child
- Epinephrine
(blood)
- Female
- Fludrocortisone
(therapeutic use)
- Humans
- Hypotension, Orthostatic
(diagnosis)
- Male
- Norepinephrine
(blood)
- Pacemaker, Artificial
- Posture
(physiology)
- Receptors, Adrenergic, beta
(physiology)
- Sodium Chloride
(therapeutic use)
- Syncope
(etiology, prevention & control)
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