Abstract 15223: Impact of Contact Force Sensing on Outcomes During Ablation of Persistent Atrial Fibrillation: The Multicenter, Randomized TOUCH AF Trial
Introduction: The impact of contact force sensing (CFS) on outcomes of ablation of persistent atrial fibrillation (AF) is unknown.
Hypothesis: The TOUCH AF trial (NCT01851525) compared a CFS-guided ablation strategy to a CFS-blinded strategy.
Methods: Patients (n=128) undergoing first-time ablation for drug-refractory persistent AF (episodes lasting >7 days) were randomized 1:1 to a CFS guided vs CFS blinded strategy at 5 sites in 2 countries. All procedures were performed using a mapping system and open irrigated catheter (SmartTouch) by experienced CFS operators. In the CFS guided procedure (n=64), operators visualized real-time force data; in the blinded procedure (n=64), force data was hidden from view. Wide antral pulmonary vein isolation (PVI) was performed with confirmed entrance/exit block plus a roof line with bidirectional block. Gaps after the first encircling/linear lesion set were determined and recorded. Repeat procedures using the identical randomized strategy were allowed after 3 months. Patients were followed at 3, 6, 9, and 12 months with visit, ECG, minimum 48 hours Holter, and external loop. The primary endpoint was cumulative radiofrequency (RF) time for all procedures. Any documented AF/AFL/AT >30 seconds after 3 months was a recurrence.
Results: Patients had persistent AF for 2.2±1.5 years (87% male, age 61±10 years, left atrial size 45±5 mm). Acute successful PVI and roof line were achieved in 96%. Mean force in the CFS guided and blinded arms were 15±6 g vs 15±3 g respectively. Total RF time did not differ between CFS guided and blinded (48±15 min vs 52±19 min respectively, p=0.17). Freedom from AF/AFL/AT at 12 months was 78% in both arms. Lesion gaps were associated with a significantly less force (15±10 vs 14±10 g, p=0.002) and less force time integral (FTI) (302±310 vs 261±242 gs, p<0.001) compared to non-gap lesions.
Conclusions: CFS guided ablation resulted in no difference in applied force, RF time, or 12 month outcome when used by CFS experienced operators. Lower force/FTI was associated with significantly more gaps and higher 12 month recurrence.
Author Disclosures: H. Lim: None. S. Conti: None. J. Champagne: None. L. Macle: Research Grant; Modest; St Jude Medical. Speakers Bureau; Modest; St Jude Medical. P. Novak: None. R. Weerasooriya: Speakers Bureau; Modest; Biotronik, Boehringer Ingelheim, Pfizer, Bayer. A. Verma: Consultant/Advisory Board; Modest; Bayer, Boehringer Ingelheim, Medtronic, Biosense Webster, St Jude Medical.
- © 2016 by American Heart Association, Inc.