Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-PO02 - Poster Session II (ID 47) Poster

D-PO02-181 - High Power-short Duration Radiofrequency Ablation Strategy For Cavo-tricuspid Isthmus Ablation Is Efficacious And Reduces Ablation Time (ID 1048)


Background: Cavo-tricuspid isthmus (CTI) ablation is one of the most common electro-physiologic procedure performed today. High power-short duration radiofrequency ablation lesions (RFALs) have the potential advantage of reducing procedure time. However, the feasibility, efficacy and safety of this approach has not been fully studied.
Objective: To evaluate ablation parameters from high power-short duration RFALs and compare them with conventional low power longer RFALs in patients who underwent successful CTI ablation.
Methods: RF ablation data from 12 patients undergoing PVI and CTI ablation procedure in sinus rhythm with point by point RF lesions (30-50 watts) utilizing a Thermocool Smarttouch® surround flow Biosense Webster™ ablation catheter and CARTO-3™ mapping was retrospectively analyzed. Operators were blinded to Visitag Surpoint® (VS) and Force time integral (FTI) data. CTI thickness was obtained using intra-cardiac echocardiogram images on Cartosound™ prior to the ablation procedure. All patients exhibited sustained bidirectional block of >30 minutes.
Results: One hundred and ninety seven RFALs (50 Watts; n=112 in 6 patients vs 35.8±4.4 Watts; n=85 in 6 patients; p<0.001) were analyzed from patients who exhibited sustained bidirectional block. The mean duration of individual RFAL using high power (50 Watts) was significantly shorter when compared to low power (9.2±0.9 vs 26.3±11.1 secs; p<0.001) thus reducing total CTI ablation time (168±44 vs 374±137 secs; p=0.006) and ablation time needed for every millimeter of CTI length (5.1±2.1 vs 10.4±4.2 secs/mm; p=0.02). Impedance drop (ohms), contact force (gms) and underlying CTI thickness (mm) between the 2 groups were similar (p<0.5). Reduction of bipolar electrogram (volts) was significant in both groups (P<0.001), however, high power group exhibited more robust reduction (54% vs 45%; p=0.01) despite shorter lesions. The high power group also exhibited lower FTI (154±62 vs 383±208; p<0.001) and VS (431±43 vs 487±95; p<0.001) values likely related to shorter ablation lesions. No complications were observed in any patient.
Conclusion: High power RF ablation lesions are feasible, efficacious and safe in CTI ablation procedures and hold the promise of shortening the procedure time.