ABC | Volume 114, Nº3, March 2020

Original Article Silva et al. AF ablation with rivaroxaban Arq Bras Cardiol. 2020; 114(3):435-442 Figure 2 – Radio Frequency Applications. Images generated by left atrial geometric reconstruction using an electroanatomical mapping system (Ensite/NAVX – St. Jude Medical/Abbott). A – Previous view. Dots in red show the radiofrequency applications. B – Posterior view. Blue dots show locations of radiofrequency applications where esophageal temperature increases. the RIV and WFR groups (350.1 ± 3 vs 348.9 ± 4; p = 0.79). However, a higher dose of heparin was used in the RIV group (9,414 ± 199 vs . 6,019 ± 185 IU; p < 0.0001) to maintain these optimal levels of ACT (Figure 4). Discussion AF ablation under uninterrupted warfarin use (therapeutic INR) has long been the most recommended periprocedural anticoagulation strategy for the prevention of TE events, especially stroke. 12 Most observational studies have reported low rates of stroke and hemorrhagic complications with this strategy. However, in practice, as well as in the clinical use of warfarin, it is difficult to keep INR within the therapeutic range stable in the periprocedural period, causing patients to have thromboembolic risks 13 or have their procedures suspended. The favorable clinical outcomes of DOACs 5 have encouraged their use in the scenario of AF ablation worldwide, even before the publication of further scientific evidence. Unlike clinical use, the anticoagulant effect of these drugs had not yet been tested in a distinct thrombogenic situation related to the presence of sheaths and catheters in the LA and endocardial lesions caused by RF. The initial results of dabigatran as an anticoagulant drug during AF ablation were unfavorable, with higher rates of hemorrhagic and embolic complications. 14 However, it was suspected that discontinuation of the drug for 24 to 48 hours before the procedure (discontinued use) may have influenced Table 1 – Characteristics of the groups Rivaroxaban Warfarin p N 130 110 - Age (years) 57.8 ± 1 60.6 ± 1 0.055 Male 96 (73.8%) 86 (78%) 0.45 BMI 28.3 ± 0.3 28.6 ± 0.4 0.51 Heart disease 28 (21%) 21 (19%) 0.74 CHA 2 DS 2 -VASC 1.32 ± 0.1 1.23 ± 0.1 0.38 Paroxysmal AF 82 (63%) 65 (59%) 0.59 LVEF (%) 62.26 ± 0.6 65.5 ± 0.6 0.16 LADD (mm) 42 ± 0.6 41.7 ± 0.7 0.81 Isolated PVs (%) 100 100 1 Linear Ablation 14 (10.8%) 26 (23%) 0.009 CFAE 4 (3%) 21 (19%) < 0.0001 CT isthmus 35 (26.9%) 37 (33.6%) 0.26 BMI: body mass index; LVEF: left ventricular ejection fraction; LADD: left atrial diastolic diameter; PVs: pulmonary veins; CFAE: complex fractional atrial electrograms; CT: Cavo-tricuspid. 438