THE HEART-RATE RESPONSE TO CAROTID-ARTERY MASSAGE IN A SAMPLE OF HEALTHY ELDERLY PEOPLE

Carotid artery massage was carried out in a cross-section of 95 health y elderly subjects (51 men and 44 women, mean age of 74 years) to asse ss the heart rate response and associated symptoms, These subjects wer e drawn from a larger group of randomly selected healthy elderly peopl e living in Southampton. They had no history of myocardial infarction or stroke and were not taking any drugs that might enhance the carotid sinus reflex. A continuous distribution of response io carotid artery massage was seen with a median percent change in RR interval of 11.6% (IQR 22.9%); 66% had a percent change in RR interval of < 20%, 90% ha d a change of < 50%, and 9.5% a change of > 100%. Carotid sinus hypers ensitivity persensitivity (sinus arrest > 3 s) was found in 4 previous ly asymptomatic subjects; a prevalence of 4.2% (95% Cl 1.2%-10.4%), an d this was associated with dizziness in 2 of these 4 subjects. Dizzine ss also accurred in one other subject who had a change in RR interval of 178%. The definition of an abnormal carotid sinus reflex is arbitra ry given the continuous RR interval response to carotid artery massage . In diagnosing carotid sinus syndrome, the RR interval response to ca rotid artery massage alone is not sufficient, as this maneuver must al so reproduce the patient's presenting symptoms.