Utility of a single-stage isoproterenol tilt table test in adults: a randomized comparison with passive head-up tilt.
OBJECTIVE
This study was conducted to develop a time-efficient tilt table test.


BACKGROUND
Current protocols of tilt table testing are quite time-consuming. This study was designed to assess the diagnostic value, tolerance and procedural time of a single-stage isoproterenol tilt table protocol.


METHODS
A single-stage isoproterenol tilt table test was compared with the passive tilt table test. The study was prospectively designed in a randomized and crossover fashion.


RESULTS
The study population consisted of 111 patients with a history of syncope (mean age 55 +/- 20 years). Of the total, 62 patients (56%; 95% confidence interval, 46% to 65%) had a positive vasovagal response during isoproterenol tilt table testing and 35 (32%; 23% to 41%) during passive tilt table testing (p = 0.002). The mean procedural times of the study population were 11.7 +/- 3.6 min and 36.9 +/- 13.3 min for isoproterenol and passive tilt table testing, respectively (p < 0.001). All patients tolerated single-stage isoproterenol testing. In the 23 control subjects (mean age 34 +/- 11 years), the apparent specificities were 91% (72% to 99%) and 83% (61% to 99%) for passive and single-stage tilt table testing, respectively.


CONCLUSIONS
The single-stage isoproterenol tilt table test was more effective in inducing a positive vasovagal response in an adult population than the standard passive tilt table test, and it significantly reduced the procedural time. The increase in positive yield was associated with a moderate decrease in apparent specificity. These observations support the conclusion that single-stage tilt table testing could be a reasonable diagnostic option in patients undergoing syncope evaluation.
Shen
W K
WK
Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA.
Jahangir
A
A
Beinborn
D
D
Lohse
C M
CM
Hodge
D O
DO
Rea
R F
RF
Hammill
S C
SC
D000328:Adult; D000368:Aged; D018592:Cross-Over Studies; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007545:Isoproterenol; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013566:Sympathomimetics; D019462:Syncope, Vasovagal / Q000175:diagnosis*; D018667:Tilt-Table Test
D013566:Sympathomimetics; D007545:Isoproterenol