Optimization of Cryoablation Catheter-Tissue Contact Using the Contact Index
Kentaro Hayashi1, Takeshi Kitamura1, Chihiro Izumi2
1Department of Cardiology, Arrhythmia Center, Ageo Central General Hospital, Ageo City, Saitama, Japan.
Introduction:
Cryoablation is widely used for septal paroxysmal supraventricular tachycardia because of its lower risk of atrioventricular block; however, real-time quantitative assessment of catheter-tissue contact is limited.
Methods And Results:
We describe a modified configuration enabling visualization of the contact index (CI) during cryoablation with the Freezor Xtra catheter, supported by in vitro validation and two clinical cases. In vitro testing demonstrated progressive CI elevation with decreasing catheter-tissue distance. Successful lesions were achieved at CI values of approximately 20%-25%. CI increased despite minimal electrogram changes and correlated with tissue proximity.
Conclusion:
CI-guided cryoablation is feasible and may improve contact assessment during septal ablation.
