Cardiac Autonomic Denervation for Cardio-inhibitory Syncope

Cardiac Autonomic Denervation for Cardio-inhibitory Syncope

Background: Autonomic system modification is an established therapeutic approach that has been increasingly used for the treatment of vagal-related symptomatic bradycardia, such as cardio-inhibitory vasovagal syncope1-12.

Although convincing results had been reported from small populations, a large randomized study providing robust evidence on the efficacy of this approach has not yet been performed.

Hypothesis: Cardiac autonomic system modification is effective for the treatment of vagal-related symptomatic bradycardia, and is associated better clinical results as compared to placebo.

Inclusion Criteria:

• Aged between 18 and 70 years old.
• Cardio-inhibitory response (VASIS 2A or 2B) during tilt test, or after carotid sinus massage.
• Patients with bradycardia mediated by vagal hypertonia documented on 24-hour Holter monitoring and a clear relationship with symptoms.

Exclusion Criteria:

• Ages under 18 and over 70
• Presence of structural heart disease documented by echocardiography.
• Hypothyroidism and hyperthyroidism, drug effects, obstructive sleep apnea and other causes of secondary bradycardia.
• Anatomical disease of the conduction system.