Reflex syncope manifesting as orthostatic complete heart block

Area of Science:

• Cardiology
• Electrophysiology
• Internal Medicine

Background:

• Orthostatic intolerance is a common clinical presentation.
• Syncope can result from various cardiovascular etiologies.
• Postural heart block is an uncommon cause of syncope.

Observation:

• A 52-year-old female patient experienced recurrent episodes of dizziness and syncope.
• Symptoms were consistently triggered by assuming an upright posture.
• Supine electrocardiography showed normal atrioventricular conduction.

Findings:

• Upon assuming the upright posture, the patient rapidly developed advanced atrioventricular block.
• The atrioventricular block progressed to complete heart block in the upright position.
• This condition was identified as orthostatic heart block.

Implications:

• Orthostatic heart block should be considered in the differential diagnosis of syncope, especially with postural triggers.
• Understanding this phenomenon is crucial for accurate diagnosis and management.
• Further research may elucidate the underlying mechanisms of orthostatic heart block.