Carotid Sinus Syndrome

Background

Carotid Sinus Syndrome is diagnosed with Carotid Sinus Massage.
This procedure should be avoided in patients with carotid bruits or a history of cerebrovascular events or transient ischemic attacks
This reflex response has two components:
- A cardioinhibitory component, due to enhanced parasympathetic tone, manifested by slowing of the sinus rate or prolongation of the PR interval and advanced atrioventricular block, alone or in combination with
- A vasodepressor component, due to decreased sympathetic activity, resulting in loss of vascular tone and hypotension, independent of changes in heart rate.
Carotid sinus hypersensitivity is diagnosed when a ≥ 50 mm Hg reduction in systolic blood pressure or a ventricular pause of ≥ 3 s occurs when a 5-10 s carotid sinus massage is done.
The prevalence increases with age and with comorbidities (cardiovascular, cerebrovascular,and neurodegenerative) and may be present in up to 45% of elderly patients with syncope, falls, and dizziness.

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