Figure 1 The study selection process according to the PRISMA.
Abbreviations: CNKI, China National Knowledge Infrastructure; DC,
deceleration capacity; AF, atrial fibrillation.
Data extraction and quality assessment
Two authors (PKZT, LZH) respectively extracted the following
information: (1) participant demographics, including age, gender, and
sample size; (2) cardiac investigations, including left atrial diameter
(LAD) and left ventricular ejection fraction (LVEF); (3) AF types; (4)
comorbidities; (5) follow-up duration; (6) details about CA; (7) AF
recurrence rates; (8) the pre- and post-ablation data on DC; (9) the
ratios based on DC for predicting AF recurrence, including the odds
ratio (OR), relative risk (RR), or hazard ratio (HR); and (10) main
findings related to DC. Regarding to AF recurrence, atrial
tachyarrhythmia (AT) lasting for 30 s during the first 3 months of
follow-up was defined as early recurrence, while AT occurring after a
blanking period of 3 months was regarded as late recurrence.
The Newcastle-Ottawa Scale (NOS), a specialized tool for assessing the
risk of bias in observational studies, was utilized to evaluate the
quality of the included studies by two investigators (PKZT, CAY)
independently of each other.20 Discrepancies between
two reviewers were addressed through consultation with the senior author
(ZLH) until a consensus reached.
Statistical analysis
Continuous variables were expressed as mean values, together with
standard deviations (SDs) if applicable, and categorical parameters were
presented as percentages. According to the follow-up durations of the
included articles, comparisons of DC were performed with the following
specified time ranges: prior to ablation, within 3 days post-ablation,
and after 3 months post-ablation. Weighted means and SDs of DC in
patients with and without AF recurrence were calculated and unpaired
Student t test was performed in each period, respectively.
Weighted mean differences (WMDs) of DC between recurrence and
non-recurrence groups, with 95% confidence interval (CI), were
calculated when a fixed- or random-effect model was used in the
meta-analysis. A fixed-effect model would be adopted to pool WMDs unless
heterogeneity estimated with the I 2 index and Q
statistic was significant; otherwise, a random-effect model would be
utilized (I 2 > 50% or P< .05). ORs based on DC post-ablation for predicting the risk
of AF recurrence were transformed logarithmically and the corresponding
standard error (SE) was calculated from 95% CI. If HRs or RRs were
available only, they would be considered as the best estimate of ORs.
Since significant heterogeneity was observed, a random-effect model was
adopted to calculate pooled OR. The stability of the outcomes was
assessed with sensitivity analyses performed by omitting one study at a
time. Regarding to publication bias, funnel plots were presented, but
tests for funnel plot asymmetry were not suggested due to a relatively
small number of the studies included in the meta-analysis (fewer than 10
studies).21 P < .05 was regarded as
statistical significance. The R
statistical software (version 4.0, R Foundation for Statistical
Computing, Vienna, Austria) was used to perform all the statistical
analyses.
Results