Vasovagal syncope (VVS) is a transient loss of consciousness that currently imposes
a high burden on health care systems with limited evidence of the comparative efficacy
of available pharmacologic interventions. This study aims to compare all pharmacologic
therapies suggested in randomized controlled trials (RCTs) through systematic review
and network meta-analysis. A systematic search in PubMed, Embase, Web of Science,
and Cochrane Library was conducted to identify RCTs evaluating pharmacologic therapies
for patients with VVS. The primary outcome was spontaneous VVS recurrence. The secondary
outcome was a positive head-up tilt test (HUTT) after receiving intervention, regarded
as a lower level of evidence. Pooled risk ratio (RR) with 95% confidence interval
(CI) was calculated using random-effect network meta-analysis. Pairwise meta-analysis
for comparison with placebo was also performed when applicable. The surface under
the cumulative ranking curve analysis was conducted to rank the treatments for each
outcome. Twenty-eight studies with 1744 patients allocated to different medications
or placebo were included. Network meta-analysis of the reduction in the primary outcome
showed efficacy for midodrine (RR 0.55; 95% CI 0.35–0.85) and fluoxetine (especially
in patients with concomitant anxiety) (RR 0.36; 95% CI 0.16–0.84). In addition, midodrine
and atomoxetine were superior to other treatment options, considering positive HUTT
(RR 0.37; 95% CI 0.23–0.59; and RR 0.49; 95% CI 0.28–0.86, respectively). Overall,
midodrine was the only agent shown to reduce spontaneous syncopal events. Fluoxetine
also seems to be beneficial but should be studied further in RCTs. Our network meta-analysis
did not find evidence of the efficacy of any other medication.
Graphical abstract
Graphical Abstract
Keywords
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Article info
Publication history
Published online: December 09, 2022
Footnotes
Funding Sources: The authors have no funding sources to disclose.
Disclosures: The authors have no conflicts of interest to disclose.
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