[Usefulness of a protocol for carotid sinus massage in supine and erect postures in patients with syncope without other cardiovascular or neurological diseases]

Abstract

Background: Carotid sinus massage is a first level test when investigating the cause of syncope. It is normally performed in the supine and erect positions. However, there is no standard complete protocol. So we have devised a new protocol to evaluate the utility of carotid sinus massage in different postures and the influence of patients age on the response.

Methods: Two groups of subjects were selected: a group of 167 patients (mean age 50 ys +/- 18, 105 males, 62 females) with a history of syncope without cardiovascular and neurological disease and 20 asymptomatic control subjects (mean age 52 ys +/- 13, 11 males, 9 females). Carotid sinus massage was performed supine, just after passive tilt, after 5 minutes of tilt and just after passive return to supine. If a pause > 3" was detected, the protocol was repeated after atropine i.v. injection.

Definitions: Borderline vasodepressor: blood pressure reduction > 30 but < 50 mm Hg without symptoms; vasodepressor: blood pressure reduction > 50 mm Hg or > 30 mm Hg with symptoms like dizziness, vertigo or syncope; cardioinhibitory: pause > 3"; mixed: cardioinhibitory with blood pressure reduction > 30 mm Hg after atropine.

Results: Carotid sinus massage gave all informations in the supine position in 14 (12%) patients, after passive tilt in 67 (57%), after 5 minutes of tilt in 30 (26%), and after return to supine in 6 (5%). The responses were: 13 (8%) borderline vasodepressor, 32 (19%) vasodepressor, 2 (1%) cardioinhibitory, 70 (42%) mixed, 50 (30%) negative. Positive responses were more frequent in patients over 45 years (90% versus 43%). In the control group only 3 (15%) positive responses were elicited (2 borderline vasodepressor, and 1 vasodepressor, all in subjects over 45).

Conclusions: This protocol for carotid sinus massage evidenced positive responses in 70% of patients with syncope without cardiovascular and neurological disease; cardioinhibitory responses are rare (2%); positive responses are more frequent in patients over 45 years; the protocol specificity was 85%.