5708
document
Comparison of provocative tests for unexplained syncope : isoprenaline and glyceryl trinitrate for diagnosing vasovagal syncope . AIMS To compare the sensitivity , specificity and adverse event profile of glyceryl trinitrate head-up tilt with isoprenaline head-up tilt in the diagnosis of vasovagal syncope in patients with unexplained syncope and healthy controls . METHODS AND RESULTS Forty-eight patients with unexplained syncope and negative passive head-up tilt at 70 degrees for 40 min , and 14 healthy controls underwent glyceryl trinitrate head-up tilt and isoprenaline head-up tilt ( maximum dose 5 microg x min ( -1 ) ) one week apart in random order . Outcome measures were production of symptoms ( syncope , pre-syncope ) with development of hypotension . In those with negative passive head-up tilt , the sensitivity of glyceryl trinitrate for diagnosing vasovagal syncope was 48 % and the specificity was 71 % . Glyceryl trinitrate was well tolerated . Isoprenaline sensitivity was 21 % with specificity 64 % . Side-effects prevented completion of the test in 68 % . Commonest adverse events were the development of hypertension or tachycardia and intolerable flushing or nausea . CONCLUSIONS Glyceryl trinitrate head-up tilt is as effective as isoprenaline head-up tilt as a provocative agent for vasovagal syncope and has a lower incidence of adverse events .
5709
Intervention_Pharmacological
isoprenaline
5710
Intervention_Pharmacological
glyceryl trinitrate
5711
Intervention_Pharmacological
glyceryl trinitrate
5712
Intervention_Pharmacological
isoprenaline
5713
Intervention_Pharmacological
glyceryl trinitrate head-up tilt
5714
Intervention_Pharmacological
isoprenaline head-up tilt
5715
Intervention_Pharmacological
glyceryl trinitrate
5716
Intervention_Pharmacological
Isoprenaline
5717
Intervention_Pharmacological
Glyceryl trinitrate head-up tilt
5718
Intervention_Pharmacological
isoprenaline head-up tilt
5719
Outcome_Physical
vasovagal syncope .
5720
Outcome_Physical
production of symptoms ( syncope , pre-syncope ) with development of hypotension .
5721
Outcome_Physical
sensitivity of glyceryl trinitrate
5722
Outcome_Physical
vasovagal syncope
5723
Outcome_Other
tolerated
5724
Outcome_Other
Isoprenaline sensitivity
5725
Outcome_Adverse-effects
Side-effects
5726
Outcome_Physical
development of hypertension
5727
Outcome_Adverse-effects
or
5728
Outcome_Physical
tachycardia
5729
Outcome_Adverse-effects
and
5730
Outcome_Physical
intolerable flushing
5731
Outcome_Adverse-effects
or
5732
Outcome_Physical
nausea
5733
Outcome_Adverse-effects
.
5734
Outcome_Other
effective
5735
Outcome_Physical
vasovagal syncope and has a lower incidence of adverse events .