Impact of catheter contact angle on lesion formation and durability of
pulmonary vein isolation
Introduction Little is known on the effect of catheter contact angle on
lesion formation and durability of pulmonary vein isolation (PVI).
Methods Both in vitro experiment and retrospective observational study
were conducted. For in vitro experiment, radiofrequency lesions were
created on explanted swine hearts in three different catheter contact
angles (0°, 45°, and 90°). In the retrospective observational study, we
assessed patients who had undergone repeat catheter ablation due to
atrial fibrillation recurrence after initial PVI. When pulmonary vein
(PV) reconnection was observed, we analyzed the previous ablation points
within and without the gap area. The gap areas were defined where
ablation had changed the PV activation sequence or eliminated the PV
potential in the repeat session. Results In the in vitro experiment,
lesion width was the smallest (5.3 ± 0.4 mm) in perpendicular contact
compared to 0° (vs 5.8 ± 0.5 mm, p=0.040) and 45° (vs 6.4 ± 0.4 mm,
p<0.001). In the retrospective observational study, we
assessed 666 tags of 16 patients with PV reconnections, and 60 tags were
in the gap area. Tags in the gap area had longer interlesion distance
(odds ratio [OR] 1.49, p < 0.001), greater contact force
variability (OR 1.03, p = 0.008), and higher rate of perpendicular
contact (OR 3.26, p < 0.001) on multivariate analysis.
Conclusion Perpendicular contact was associated with a smaller lesion
and higher rate of PV reconnection.