Adenosine-Sensitive Syncope: Does it Really Exist?
Adenosine-sensitive syncope has recently been identified as a cause of syncope in some patients affected by unexplained syncope who have an abnormal response to adenosine triphosphate (ATP) test and a negative work-up after complete conventional investigations . Some authors [2–4] have hypothesized that adenosine could be an important modulator in triggering a vasovagal response in susceptible patients. Indeed, the injection of a bolus of adenosine during head-up tilt testing (HUT) has been seen to provoke a vasovagal response in susceptible patients with syncope with a positivity rate comparable to that of isoproterenol [2, 3]. The ATP test has been suggested as a useful tool to identify a subgroup of patients at high risk of severe cardioinhibitory responses of vagal origin . In a recent study , we evaluated the possible relationship between adenosine-sensitive syncope and tilt-induced vasovagal syncope. For this purpose, we performed both the ATP and HUT tests in a group of consecutive patients with syncope of uncertain origin, and compared the clinical characteristics of the patients who had a positive response to one or both tests.
KeywordsAdenosine Triphosphate Atrioventricular Block Vasovagal Syncope Syncopic Episode Sinus Arrest
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- 3.Mittal S, Stein K, Markowitz S, Lerman B (1997) Can adenosine replace isoproterenol during tilt testing? Circulation 96:1–221 (abstr)Google Scholar
- 5.Brignole M, Gaggioli G, Menozzi C, Del Rosso A, Costa S, Bartoletti A, Bottoni N, Lolli G (1999) The different clinical features of adenosine-sensitive syncope and tiltinduced vasovagal syncope (in press)Google Scholar
- 7.Petersen MEV, Williams TR, Sutton R (1995) A comparison of non-invasive continuous finger blood pressure measurements (Finapres) with intra-arterial pressure during prolonged head-up tilt. Eur Heart J 16:1647–1654Google Scholar
- 14.Sutton R (1996) Vasovagal syncope: clinical features, epidemiology, and natural history. In: Blanc JJ, Benditt D, Sutton R (eds) Neurally mediated syncope: pathophysiology, investigations, and treatment. Futura, Armonk, NY, pp 71–76Google Scholar