Diagnosis of carotid sinus hypersensitivity in older adults: carotid sinus massage in the upright position is essential

Objective-To assess the diagnostic value of supine and upright carotid sinu s massage in elderly patients. Design-Prospective controlled cohort study. Setting-Three inner city accident and emergency departments and a dedicated syncope facility. Patients-1375 consecutive patients aged >55 years presenting with unexplain ed syncope and drop attacks; 25 healthy controls. Interventions-Bilateral supine carotid sinus massage, repeated in the 70 de grees head up tilt position if the initial supine test was not diagnostic o f cardioinhibitory and mixed carotid sinus hypersensitivity. Main outcome measures-Diagnosis of cardioinhibitory or mixed carotid sinus hypersensitivity; clinical characteristics of supine v upright positive gro ups. Results-226 patients were excluded for contraindications to carotid sinus m assage. Of 1149 patients undergoing massage, 223 (19%) had cardioinhibitory or mixed carotid sinus hypersensitivity; 70 (31%) of these had a positive response to massage with head up tilt following negative supine massage (95 % confidence interval, 25.3% to 37.5%). None of the healthy controls showed carotid sinus hypersensitivity on erect or supine massage. The initially p ositive supine test had 74% specificity and 100% sensitivity; these were bo th 100% for the upright positive test. The clinical characteristics of the supine v upright positive subgroups were similar. Conclusions-The diagnosis of carotid sinus hypersensitivity amenable to tre atment by pacing may be missed in one third of cases if only supine massage is performed. Massage should be done routinely in the head up tilt positio n if the initial supine test is negative.