Randomized Trial Comparing Pulmonary Vein Isolation Using the SmartTouch Catheter with or Without Real-time Contact Force Data

Background: Contact force (CF) information may improve the safety and efficacy of ablation for paroxysmal atrial fibrillation (PAF).

Objective: The purpose of this study was to assess the impact of CF data on ablation for PAF.

Methods: Patients undergoing first-time PAF ablation were randomized at 7 UK centers to ablation with (CF-on) or without (CF-off) CF data available to the operator, using the same ablation catheter and mapping system. An ablation CF of 5-40g was targeted. Pulmonary vein (PV) reconnection was assessed with adenosine at 60 minutes. Follow-up for arrhythmia recurrence was for 1 year with 7-day Holter recordings at 6 and 12 months.

Results: One hundred seventeen patients were studied (59 CF-on, 58 CF-off). In the CF-on group, a reduction in acute PV reconnection rates (22% vs 32%, P = .03) but no significant difference in 1-year success rates off antiarrhythmic drugs (49% vs 52%, P = .9) was observed. There was no difference in major complication rates: 2 of 59 (3%) CF-on, 3 of 58 (5%) CF-off (P = .7). Procedural and fluoroscopy times were not significantly different (P>.5). Overall mean CFs per ablation were not different between groups (13.4 [9.1-19.6]g CF-on, 13.4 [7.4-22.4]g CF-off, P = .5), but a greater proportion of readings in the CF-on group were in the target range (80% vs 68%, P<.001).

Conclusion: This randomized multicenter study demonstrated that CF data availability was associated with reduced acute PV reconnection but not improved 1-year success rates, procedural and fluoroscopy times, or complication rates. There was a reduction in extremes of CF, above and below the study target range, suggesting greater CF control during ablation.