Mechanism of Early Recurrence
Previous studies with patients in
the non-CF era have reported an approximately 50% prevalence of ER
after ablation and a higher incidence of LR, ranging between 41.1% and
90%, in cases with ER during the 3-month blanking
period.3,
9, 10 The
present study showed that 55.7% patients in the Non-CF group had ER
during the 3-month blanking period and 59.3% of them had LR. These
results were consistent with those of previous studies. On the other
hand, in CF ablation cases, only 35.2% cases experienced ER, and 52.4%
of those with ER also had LR.
These results were also consistent with those of a previous
study.11
The mechanisms of ERs are considered to be post-ablation transient
factors, such as inflammatory changes, in addition to reconnection of PV
or residual extra-PV
triggers.1 A previous
histopathological study had demonstrated that RF energy delivery causes
inflammatory responses after the ablation
procedure.12Furthermore, a greater inflammatory response after an RF ablation
procedure has been associated with ER, and a longer RF ablation time and
total procedure time are significant predictors for post-ablation
inflammation and myocardial
injury.13 In the
present study, the degree of elevation in WBC and CRP levels after
ablation was significantly smaller in patients who underwent CF-guided
ablation (Table 2). The RF delivery time was shorter, and the amount of
RF energy delivered was smaller in patients who underwent CF-guided
ablation (Table 2). Appropriate force of tissue–catheter contact, and
stability of RF delivery provided by CF technology may result in more
successful PVI, without excessive RF delivery, and will reduce the
inflammatory response. A lower inflammatory response may partly explain
the lower incidence of ER in the CF-group.