3. Results
3.1 Search resultsOur search strategy yielded 815 potentially relevant articles (465
articles from EMBASE and 350 articles from MEDLINE). After the exclusion
of duplicated articles, 732 articles underwent title and abstract
review. At this stage, 633 articles were excluded as they
were not cohort, case-control, or
randomized controlled trials, were not conducted in BrS patients or the
titles and abstracts were not relevant. This left 99 articles for
full-length review. Another 81 studies were excluded as they did not
report data regarding SCB use, outcome of interest, or did not provide
sufficient data to calculate OR. Therefore, a total of 18 studies were
included in this meta-analysis (3, 14-30). Figure 1 outlines the search
and literature review process.
3.2 Description of included studies
Eighteen studies from 2006 to 2018 were included in this meta-analysis
involving 4,099 Brugada syndrome patients. Seventeen of 18 studies
involving 3,596 Brugada syndrome patients reported the incidences of MAE
in spontaneous Type-1 and drug challenge induced Type-1 Brugada pattern
(3, 14-26, 28-30). Three of eighteen studies involving 776 Brugada
syndrome patients reported MAE during drug challenge testing (16, 27,
30). Six of eighteen studies involving 541 Brugada syndrome patients
reported symptomatic versus asymptomatic patients who had undergone drug
challenge testing (3, 14, 21, 23, 24, 30). Mean follow-up was 4.5 years
and 57.6% of Brugada syndrome patients were diagnosed by drug challenge
induced Type-1 Brugada pattern. A summary of study characteristics is
shown in Table 1.
3.3 Quality assessment of included studiesThe NOS of included studies are described in Supplement Table. The NOS
uses a star system (0 to 9) to evaluate included studies on 3 domains:
selection, comparability, and outcomes. Higher scores represent a higher
study quality.