Introduction
Pulmonary vein isolation (PVI) has evolved into a widely accepted and
effective strategy for the treatment of atrial fibrillation (AF), which
is recommended by the latest guidelines.1 However, we
occasionally experience recurrences of atrial tachyarrhythmias after a
successful PVI. Early recurrences of atrial tachyarrhythmias (ERATs)
during a 90-day blanking period occur in up to 50% of patients after a
PVI.2,3 The pathophysiological mechanisms of ERATs are
attributed to acute inflammatory changes due to energy deliveries,
delayed effects of ablation due to lesion consolidation, and
reconnections of isolated PVs.3-5 ERATs reduce the
patients’ quality of life owing to various symptoms. In addition, ERATs
predict late recurrences after PVI.2,3,6 Therefore, it
is important to reduce the incidence of ERATs, even for short periods of
time.
Ablation index (AI) is a novel marker of the lesion quality during
radiofrequency catheter ablation (CA) and incorporates power in addition
to contact force (CF) and time in a weighted
formula.7-9 An AI-guided AF ablation improves the
incidence of late atrial tachyarrhythmia recurrences as compared to the
conventional contact force (CF) guided ablation.8,10However, little is known whether or not an AI-guided PVI can reduce
ERATs.
We hypothesized that an AI-guided PVI, which is a novel technology of
radiofrequency CA, could reduce the frequency of ERATs. Hence, this
study aimed to clarify the effect of AI-guided PVI on ERATs as compared
to the conventional CF-guided PVI.