Main study findings
- Use of LSI targets does not fully compensate for use of lower powers:
lower RF powers produce smaller impedance drops regardless of the
target LSI value. For any target LSI, lower powers might produce
smaller lesions than higher powers.
- Contact force values and catheter stability are more important
determinants of impedance drop when using lower powers. Switching to
higher power could be beneficial in case of low contact force or
catheter instability.
- For any combination of power and contact force, LSI targets can be
identified, corresponding to achievement of maximum impedance drop. In
its current formula, LSI might be more an indicator of lesion
completeness than of lesion size.
- The correlation of LSI with maximum impedance drop depends on contact
force variability used during ablation. The addition of an indicator
of catheter stability in the LSI formula could improve its predictive
value for lesion size.