P. Ambrosi et al., VALUE AND LIMITATIONS OF THE TILT TEST IN THE DIAGNOSIS OF UNEXPLAINED SYNCOPE, Archives des maladies du coeur et des vaisseaux, 85(3), 1992, pp. 345-350
This study was undertaken to assess the usefulness of the head-up tilt
test in the diagnosis of vasovagal syncope and to evaluate the indica
tions of this investigation. The test consists in a 30 minute period i
n the horizontal decubitus position followed by a 60-degrees head-up t
ilt position for 30 minutes. In the 26 subjects in whom the diagnosis
of repeated vasovagal syncope had been made on the basis of typical pr
odromic symptoms after exclusion of all other causes, the test induced
a vasodepressive or vagal reaction in 10 cases (38 %) 20 +/- 4 minute
s after tilting. In 8 patients in whom the test was performed within 4
8 hours of their syncopal episode, a similar malaise was induced in 7
cases. Twenty patients with repeated malaise without loss of conscious
ness had no symptoms during the test which was also negative in 10 nor
mal control subjects. In a group of 27 subjects with unexplained synco
pe after clinical and paraclinical investigations, the test was accomp
anied by a malaise on five occasions (19 %). Using this protocol, the
tilt test had good specificity but moderate sensitivity in the diagnos
is of vasovagal syncope. Its sensitivity increased when performed with
in 48 hours of syncope. It is of no value in the diagnosis of recurren
t malaise without loss of consciousness.