Choice of Steerable Sheath Impacts Contact Force Stability During
Pulmonary Vein Isolation
Purpose: A stable contact force (CF) is correlated with more effective
radiofrequency ablation (RFA) lesions and long-term procedural outcomes.
Efforts to improve catheter stability include jet ventilation, pacing,
steerable sheaths, and CF sensing ablation catheters. This study
compares CF stability and effective RF lesions between two commercially
available steerable sheaths. Methods: Thirty patients underwent first
time RFA at a single center using the Agilis NxT or SureFlex Steerable
Sheath. High power short duration RFA was utilized targeting a 10Ω drop.
Sheath performance was assessed for the entire procedure and around each
pulmonary vein (PV) in terms of mean CF, CF variability, RF time per
lesion, and inefficient contact lesions (defined as lesions with CF
< 5g for at least 10% of the RF delivery time). Results:
Operator-targeted mean CF was achieved using both sheaths; however,
overall CF variability was 12.8% lower using the SureFlex sheath (p =
0.08). CF variability was generally 16% greater in the right PVs than
the left PVs (p = 0.001), but trended lower with the SureFlex sheath.
There were 8% more inefficient contact lesions using Agilis as compared
to SureFlex (p = 0.035), especially in the right inferior PV (p =
0.009). RF time per lesion was on average 12% (1.4s) shorter using
SureFlex than Agilis (p < 0.05). Conclusion: Choice of
steerable sheath may affect catheter stability and potential lesion
quality, especially in the right PVs.