Abstract Funding Acknowledgements Type of funding sources: None. Background In atrial fibrillation (AF) patients, pulmonary vein isolation by means of catheter ablation (CA) is the most effective therapeutic option in order to maintain sinus rhythm. To improve successful PV isolation and effective lesion creation, contact force (CF)-sensing catheters were developed and have become routinely available. Previous studies did not always show superior clinical efficacy in comparison with non-CF CA. Moreover, data about long term clinical outcome are still lacking, especially by patients with persistent atrial fibrillation. Purpose The aim of the present study was to compare the outcome of CF-controlled ablation versus non-CF guided radiofrequency (RF) ablation of AF with regard to ablation characteristics and AF recurrence. Methods Consecutive patients, who underwent a mean 1.7±0.9 point-by-point RF CA for AF at our hospital between January of 2014 and October of 2017, were enrolled in the study. 354 patients were ablated without CF. After routine availability of CF catheters in October of 2016, 165 consecutive patients were ablated using CF. In case of crossover between the groups, follow up was censored. The primary endpoint was any recurrence documented as symptomatic or asymptomatic atrial tachycardia or atrial fibrillation >30 s after the 3-month blanking period. Secondary endpoints were procedural characteristics and periprocedural complications. Results 62% of the enrolled patients had persistent AF. There were no significant differences in baseline characteristics (male gender 63% vs 62%, P=0.846; persistent AF 61% vs. 65%, P=0.496; BMI 29.0±5.2 vs 29.3±5.2 kg/m2, P=0.582; hypertension 76% vs 80%, P=0.369; coronary artery disease 14% vs 20%, P=0.076; left atrial diameter 43.3±7.0 vs 43.8±7.3 mm, P=0.386; diabetes 13% vs 10%, P=0.312; sleep apnoea 7% vs 10%, P=0.167) between the groups, except for older age in the CF group (62.8±10.0 vs 65.0±10.4 years, P=0.021). In the first 12 months arrythmia-free survival was significantly higher in the CF group (Figure 1, Log-Rank (Mantel-Cox) P=0.049). Over 2.8 ± 1.8 years of follow-up, 47% of the patients in the CF group remained free of AF recurrence compared to 36% in the non-CF group (Log-Rank (Mantel-Cox) P=0.236). In multivariable Cox regression analysis using backward elimination, non-CF ablation was an independent risk factor for AF recurrence (HR=1.31; P=0.027) besides age (HR=1.023; P=0.001), persistent AF (HR=1.481; P=0.001), and left atrial diameter (HR=1.023; P=0.004). All other clinical factors were non-significant (Figure 2). Total fluoroscopy time (27.6±16.0 vs. 14.4±7.9 min) and total procedure time (133.4±38.8 vs. 110.1±28.0 min) were significantly lower for CF guided CA (P<0.001). Complication rates did not differ between groups (P=0.123). Conclusions In our long-term single center study the AF recurrence rate was lower after CF PVI as compared to non-CF PVI.