This retrospective cohort study enrolled 57 drug-refractory AF patients who underwent initial PVI for AF using an open-irrigated CF catheter (SmartTouch Thermocool, Biosense Webster, Diamond Bar, CA, USA). Thirty patients were assigned to a lower CF (LCF) group (average CF ≤ 10 g) and 27 patients to a higher CF (HCF) group (average CF > 10 g). The relationship between CF and clinical outcome was analyzed.
Patients were followed-up for 317 ± 57 days after PVI. The CF was 8.1 ± 1.3 g in the LCF group and 12.4 ± 1.5 g in the HCF group. Higher average CF was associated with shorter ablation time (28 ± 6 min vs. 36 ± 9 min, p = 0.0002) and lower radiofrequency energy delivery (79 ± 18 vs. 99 ± 26, p = 0.0016) for PVI. The rate of acute PV reconnection (APVR) was similar in both groups (LCF group 60% vs. HCF group 44%, p = 0.36). Four patients (13%) in the LCF group and nine patients (33%) in the HCF group experienced AF-recurrence. Average CF did not impact on AF-recurrence during midterm clinical outcome (p = 0.09 by log-rank test). In the non-recurrence group (n = 44), average CF was higher at left posterosuperior PV and right anteroinferior PV than that in the recurrence group (n = 13) (p = 0.012 and p = 0.004, respectively).
Higher average CF decreased ablation time and radiofrequency energy delivery for PVI, but did not decrease APVR rate or improve midterm clinical outcome.