[Tilt test in the etiological diagnosis of syncope unexplained by electrophysiological study].

In order to determine the role of tilt testing in the aetiological diagnosis of syncope unexplained by electrophysiological investigation, the authors retrospectively studied the results of this test in 275 patients with a mean age of 64 +/- 16 years. These 275 patients were divided into two groups: group I: 43 patients with a mean age of 50 +/- 19 years presenting with vagal syncopes, group II: 232 patients with unexplained syncope, probably vagal: group IIa (120 patients, mean age: 67 +/- 15 years), sudden syncope: group IIb (112 patients, mean age: 67 +/- 13 years). The electrophysiological investigation was inconclusive in every case. In group II, 50% of tilt tests were positive (19% under basal conditions, 31% after isoproterenol), with 61% of positive tests in group IIa, including 31% on the basal test, and 38% of positive tests in group IIb, including 11% on the basal test. In group I, 84% of tests were positive (33% on the basal test, 51% after isoproterenol), indicating a sensitivity of the test of 84%. In 96 patients with a doubtful electrophysiological investigation, the tilt test was positive in 70% of cases, allowing specific treatment or a pacemaker to be avoided in the majority of cases. 84% of vasovagal syncopes were therefore confirmed by tilt testing; 50% of syncopes unexplained by electrophysiological investigation were demonstrated to be of vasovagal origin. The author emphasize the value of tilt testing in certain discordant situations in which the clinical context is disturbing and/or electrophysiological investigation is not completely reassuring.