During exercise testing, repeated palpation of the carotid pulse is likely to result in:

During exercise testing, repeated palpation of the carotid pulse is likely to result in:

• A. Increasing the heart rate
• B. Decreasing the heart rate
• C. An irregular heart rhythm
• D. Increasing systolic blood pressure

Answer: (B)

Stimulation of the carotid sinus triggers a reflex that tightens parasympathetic control and dampens sympathetic output, slowing the heart. When the carotid sinus is palpated, baroreceptors sense this pressure and send signals to the brainstem, which increases vagal activity to the heart and reduces its rate. In the setting of exercise testing, where the heart normally speeds up to meet metabolic demand, this reflex can blunt that response and cause the heart rate to decrease or fail to rise as expected. The primary outcome is a slowing of the heart rate, not an increase or an irregular rhythm, and while blood pressure can be affected, the most direct and consistent effect is bradycardia from the vagal reflex.

Stimulation of the carotid sinus triggers a reflex that tightens parasympathetic control and dampens sympathetic output, slowing the heart. When the carotid sinus is palpated, baroreceptors sense this pressure and send signals to the brainstem, which increases vagal activity to the heart and reduces its rate. In the setting of exercise testing, where the heart normally speeds up to meet metabolic demand, this reflex can blunt that response and cause the heart rate to decrease or fail to rise as expected. The primary outcome is a slowing of the heart rate, not an increase or an irregular rhythm, and while blood pressure can be affected, the most direct and consistent effect is bradycardia from the vagal reflex.