[Reflex syncope and syncope secondary to orthostatic hypotension]

Area of Science:

• Cardiology
• Neurology

Context:

• Reflex syncope is the most common cause of fainting, particularly in younger patients.
• It involves inadequate circulatory responses like bradycardia (cardioinhibitory type) or hypotension (vasodepressor type) following triggers such as orthostatic stress, pain, or emotional distress.
• Orthostatic hypotension, common in the elderly, results from insufficient vasoconstriction upon standing.

Purpose:

• To outline the diagnostic approaches for reflex syncope.
• To detail therapeutic strategies for managing reflex and orthostatic syncope.

Summary:

• Diagnosis primarily involves a detailed patient history, with specific testing like tilt table testing or implanted loop recorders reserved for uncertain or recurrent cases.
• Implanted loop recorders are particularly effective for diagnosing the cardioinhibitory component of reflex syncope.
• Treatment includes trigger avoidance, managing prodromal symptoms, and physical counterpressure maneuvers.
• Pharmacological treatments like alpha-adrenergic agonists and fludrocortisone are effective for orthostatic syncope.
• Pacemaker implantation may be considered for selected patients with predominantly cardioinhibitory reflex syncope.

Impact:

• Provides a comprehensive overview of reflex syncope diagnosis and management.
• Highlights the utility of specific diagnostic tools like implanted loop recorders.
• Differentiates treatment strategies for reflex versus orthostatic syncope.