What is neuro-cardiogenic syncope?

What is neuro-cardiogenic syncope?

• A. A rapid heartbeat due to exercise
• B. A decrease in blood pressure due to dehydration
• C. A paradoxical parasympathetic response causing syncope
• D. An increase in heart rate with stress

Answer: (C)

Neuro-cardiogenic syncope, also known as vasovagal syncope, refers to a sudden drop in heart rate and blood pressure, leading to fainting or syncope. This condition is caused by an abnormal reflex that combines both the nervous system and cardiovascular responses. Specifically, it involves a paradoxical parasympathetic response, where the activation of the vagus nerve causes an excessive decrease in heart rate and dilation of blood vessels, leading to reduced blood flow to the brain. This results in the individual losing consciousness.

The reflex can be triggered by various factors, such as stress, pain, or prolonged standing. Understanding the underlying mechanism helps differentiate this condition from others that may involve changes in heart rate or blood pressure but do not encompass the complex interplay of neural and cardiovascular factors seen in neuro-cardiogenic syncope.