[Diagnostic value of the tilt test in the evaluation of syncope of unknown origin. Preliminary results].
OBJECTIVE
In order to identify neurally mediated syncope, head-up tilt testing was performed in patients with recurrent unexplained syncope.


METHODS
The tests were performed in 125 patients in the fasting state, between 8:30 and 11:30 a.m. The blood pressure and heart rate were continuously monitored during 20 minutes in the resting state, and then, positioned at 60 degrees angle, for up to 40 minutes. A group of 20 patients with first negative test was submitted to intravenous isoproterenol in bolus of 2 micrograms every 2 minutes until symptoms occur or at a total dose of 8 micrograms. The test was considered positive when systolic blood pressure decreased at least 30 mmHg and the patient experimented syncope or pre-syncope.


RESULTS
In 52 patients the test was positive (41.6%), 63.5% of which had hypotension exclusively; 7.7% asystole; and 28.8% had hypotension and bradycardia. Nine of the 20 patients submitted to isoproterenol test were positive (45%). All patients recovered spontaneously after returning to supine position.


CONCLUSIONS
Head-up tilt testing is a safe and effective method for the identification of neurally mediated syncope.
Hachul
D
D
Instituto do Coração do Hospital das Clínicas-FMUSP, São Paulo.
Sosa
E A
EA
Consolim
F
F
Magalhães
L
L
Scanavacca
M
M
Martinelli
M
M
Bellotti
G
G
Pileggi
F
F
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D006801:Humans; D007024:Hypotension, Orthostatic / Q000150:complications* / Q000175:diagnosis; D007545:Isoproterenol; D008297:Male; D008875:Middle Aged; D011187:Posture / Q000502:physiology; D011237:Predictive Value of Tests; D013575:Syncope / Q000209:etiology*
D007545:Isoproterenol
Valor diagnóstico do teste de inclinação na avalicção da síncope de origem indeterminada. Resultados preliminares.