3.1 Eligible studies and characteristics of studies
A total of 120 articles were identified, and 80 remained after title
abstract screen and duplicate deletion. Altogether 71 articles were
excluded for the following reasons: 33 articles were case reports,
reviews or case series; 20 studies included no VSD patients; 12 studies
performed no TVD procedure; 3 studies provided inadequate raw data for
analysis; and 2 studies included insufficient patient population (Figure
1).
Only 9 studies were included after selection (Table 1), including 7
retrospective cohort studies, 1 respective cohort study and 1
prospective observational study. Quality assessment of included studies
was summarized in Table 2. In the study led by
Sasson11, patients were divided into three groups,
group 1 included patients with no indication for TVD, group 2 for
patients with indications for TVD and underwent TVD and group 3 for
patients with indications for TVD but underwent non-TVD procedures. Our
analysis took only group 2 and group 3 into consideration.