Carotid sinus syncope

In this condition there is exaggerated vagal discharge following carotid sinus stimulation when doing simple tasks like shaving or buttoning a tight shirt collar or even head rotation. There is reflex vasodilation and decrease in the pulse. These may combine to reduce blood pressure and cerebral perfusion in some elderly patients, causing loss of consciousness.

Carotid sinus hypersensitivity is diagnosed by applying gentle pressure over the carotid pulsation just below the angle of the jaw, where the carotid bifurcation is located. Pressure should be applied for 5 to 10 seconds. It should be done in both supine and upright position.

A normal response to carotid sinus massage is a transient decrease in the sinus rate, slowing of atrioventricular (AV) conduction, or both. Carotid sinus hypersensitivity is defined as a sinus pause longer than 3 seconds in duration and a fall in systolic blood pressure of 50 mmHg or more.

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