Limitations
The current study had several limitations, the first of which is that it
is not free from the intrinsic limitations of a retrospective analysis.
There were significant differences in the baseline characteristics
between the AF nonrecurrence and AF recurrence groups, although the
results were adjusted for such covariates. A causal relationship between
the lower incidence of the primary endpoint and sinus rhythm maintenance
by catheter ablation is therefore not clear. Second, although the AF
recurrence rate of this study was comparable to that of previous
reports,21, 22 we cannot deny that asymptomatic AF
recurrence might have been overlooked.