Neurocardiogenic syncope in children with a normal heart

Area of Science:

• Pediatric Cardiology
• Autonomic Nervous System Function
• Syncope Etiologies

Background:

• Syncope is a frequent clinical issue with diverse causes.
• Autonomic testing, particularly the tilt/orthostatic test, aids in diagnosing neurocardiogenic syncope.

Purpose of the Study:

• To review the investigation and management outcomes for children experiencing syncope with structurally normal hearts.
• To evaluate the effectiveness of specific treatments for neurocardiogenic syncope in pediatric patients.

Main Methods:

• Reviewed 162 children (ages 1-20) with syncope, analyzing case notes and autonomic test results.
• Autonomic testing included orthostatic maneuvers, carotid sinus massage, diving reflex, Valsalva maneuver, and drug responses (isoproterenol, phenylephrine).
• Measured serum epinephrine and norepinephrine levels during orthostatic testing; initiated treatment with fludrocortisone/salt and beta-blockers as needed.

Main Results:

• Orthostatic testing confirmed neurocardiogenic syncope in 62% of patients.
• Neurocardiogenic syncope patients were older, more female, and showed distinct autonomic responses (e.g., altered norepinephrine/epinephrine levels, beta-adrenergic hypersensitivity).
• Treatment led to symptom resolution or improvement in 82% of patients receiving fludrocortisone/salt and 80% receiving beta-blockers.

Conclusions:

• Pediatric patients with orthostatic test-proven neurocardiogenic syncope exhibit autonomic dysfunction and beta-adrenergic hypersensitivity.
• The established treatment protocol effectively ameliorated symptoms in the majority of affected children.
• Findings support the diagnostic utility of autonomic testing and targeted therapy for pediatric syncope.