RESULTS
Patients’ clinical and
echocardiographic
characteristics
Patients’ clinical and echocardiographic characteristics are shown per
group in Table 1. The mean duration of AF was 6 months, and mean LAD was
41 mm in both groups. Only the type of AADs used was found to differ
significantly between the 2 groups, with Class III or IV AADs given more
frequently to patients in the CBA group than to patients in the HBA
group.
Patients’ electrophysiologic
characteristics and details of the ablation
procedures
Patients’ electrophysiologic characteristics and the procedure-related
details are shown per group in Table 2. Complete PVI was achieved in all
cases. AF termination occurred significantly less frequently during HBA
than during CBA (19 [24%] vs. 31 [39%], P = 0.04). The
energy application times were equivalent for the superior PVs, but for
the inferior PVs, the energy application time was shorter in the HBA
group than in the CBA group (LIPV: 145 ± 17 vs. 162 ± 28 seconds,P < 0.001; RIPV: 145 ± 17 vs. 162 ± 28 seconds,P <0.001). Touch-up RF applications were required to
complete the PVI in 15 (19%) patients in the HBA group and 12 patients
(15%) in the CBA group (P = 0.52), and a significant
between-group difference was found in some sites requiring touch-up,
with energy applications needed at the LSPV in 12 (15%) patients in the
HBA group and at the RIPV in 5 (6%) patients in the CBA group. CTI
ablation was performed significantly more often after CBA than after HBA
(32 [41%] vs. 9 [11%], P < 0.001). No patient
received additional LA substrate ablation targeting fractionated
electrograms or low-voltage areas. There was no significant
between-group difference in the procedure time.
ISAs
Representative voltage maps displaying ISAs achieved by HBA and by CBA
are shown in Figure 3. As shown in Table 2, the total IASA + pLAWSA did
not differ significantly between the HBA group and CBA group (42.2 ± 9.5
cm2 vs. 42.5 ± 11.5 cm2, P =
0.83). However, the total IASA after HBA was significantly larger than
that after CBA (26.3 ± 11.0 cm2 vs. 21.4 ± 7.0
cm2, P < 0.001). Thus, the ISA after
HBA was greater than that after CBA (61 ± 16% vs. 51 ± 12%, P< 0.001). Distribution of the ISAs resulting from each of the
balloon systems is shown in Figure 4.
Complications
Periprocedural complications are shown per group in Table 3. The number
of patients who suffered a complication did not differ significantly
between the HBA group and CBA group (3 [4%] vs. 1 [1%],P = 0.62). Pericardial tamponade, pericarditis, and aspiration
pneumonia occurred in 1 patient each in the HBA group, but all 3
patients recovered within 2 weeks after the procedure. Phrenic nerve
paralysis occurred in 1 patient in the CBA group, and this resolved
within 2 months after the procedure. There was no periprocedural death
in either group.
Post-ablation antiarrhythmic
therapies and outcomes, per study
group
Post-ablation antiarrhythmic therapies and outcomes are shown in Table
4. Twenty-four (30%) HBA and 34 (43%) CBA patients were given 1 or
more AADs after the procedure (P = 0.10). There was no
between-group difference in the number of patients given a class I drug
(2 [3%] vs. 7 [9%], respectively; P = 0.17), class III
(amiodarone) drug (4 [5%] vs. 1 [1%], respectively; P =
0.17), or class IV (bepridil) drug (20 [25%] vs. 29 [37%],
respectively; P = 0.12). beta-blockers were given to more
patients in the CBA group than in the HBA group (23 [29%] vs. 6
[8%], respectively; P < 0.001).
During the median follow-up period of 18 (13, 26) months, 8 patients
(10%) in the HBA group and 12 patients (15%) in the CBA group
experienced AF recurrence (P = 0.34). Atrial tachycardia (AT) was
observed in 1 patient (1%) in the HBA group and 2 patients (3%) in the
CBA group. Kaplan-Meier curves for freedom from AF/AT recurrence are
shown in Figure 5. Freedom from AF/AT recurrence was similar between
patients who underwent HBA and those who underwent CBA (P =
0.69). AF/AT recurrence did not differ statistically between the HBA
group and CBA group during the during the first 18 months after the
procedure (11% vs. 18%, respectively, at 18 months; P = 0.26).
None of the clinical or procedure-related variables were found to
predict AF recurrence.