Relationship Between Carotids Sinus Massage, Test With Adenosine and Head-Up Tilt Test in Patients With Syncope

Abstract

The aim of study was comparison of results of carotids sinus massage (CSM) and adenosine test (AT) in patients with syncope diagnosed by head-up tilt test (HUTT). We observed 169 pts (81 men, 88 women) aged 18-58 yrs (x38,2 yrs) with syncope referred to HUTT. All pts underwent standard HUTT (HUTT-s) acc. To Westminster protocol. Additional tilt with isoproterenol infusion (HUTT-I) was preformed in pts with negative HUTT-s. HUTT was assessed as positive if reproduced symptoms referred by patients. Carotid sinus massage and rapid IV injection of 12 mg of adenosine were done in all pts. RR pauses > 6s induced by adenosine injection or RR pause > 3 s and/or blood pressure fall induced by CSM were assumed as positive tests results. 16 pts (9,5%) had positive AT and 18 pts (10,6%) had positive CSM. Positive AT was observed in 10% pts with negative HUTT-s; in no pts with positive HUTT-s, in 23,1 % of pts with negative HUTT-I and in 8% of positive HUTT-I Positive CSM was observed in 20% pts with negative HUTT-s; in 13,3% pts with positive HUTT-s, in no pts with negative HUTT-I and in 8% of positive HUTT-I Carotid sinus hypersensitivity was no more frequently observed in patients with positive HUTT-I than in positive HUTT-s. Positive AT results were more frequent in pts with negative results of HUTT (both HUTT-s and HUTT-I) Carotid sinus hypersensitivity as a kind of neurocardiogenic syncope seems to have different mechanism than vaso-vagal syncope. HUTT-I rather do not induce syncope by carotid hypersensitivity mechanism. Adenosine may by useful in the diagnosis of syncope in patients with negative results of head-up tilt test.