ABC | Volume 114, Nº3, March 2020

Original Article Silva et al. AF ablation with rivaroxaban Arq Bras Cardiol. 2020; 114(3):435-442 In our service, we started performing ablation under uninterrupted RIV use in mid-2016, after a long experience with uninterrupted warfarin (therapeutic INR ablation). This study aimed to evaluate the safety of performing AF ablation with RF under uninterrupted rivaroxaban use. Methods Study design This is a retrospective study in which a consecutive series of 130 patients was submitted to the first session of ablation with RF (January 2016 to October 2018) for AF treatment under uninterrupted rivaroxaban use (RIV group) and compared to a control group, consisting of 110 patients submitted to similar procedures (October 2010 to March 2017) under continuous warfarin use (WFR group) and who had INR between 2 and 3.5 on the eve of the procedure. Patients who had an INR outside the specified therapeutic range in the WFR group, and patients who used other anticoagulants or had ablation with OAC interruption were excluded from this study (Figure 1). The analyzed primary outcomes were: thromboembolic event rate (stroke/transient ischemic attack (TIA) and procedure-related major bleeding (up to 30 days). Based on the International Society on Thrombosis and Haemostasis (ISTH) criteria, major bleeding was considered: fatal bleeding; symptomatic bleeding that has affected critical areas or organs; which caused a decrease > 2 g/dL or required replacement of blood products. 7 Secondary outcomes were minor bleeding rates and parameters related to intraoperative anticoagulation, such as mean levels of activated clotting time (ACT) in the procedure and heparin doses required to maintain them at the established goal (between 300 and 400 seconds). All data were collected at hospital admission and stored in the service’s own database. All patients underwent preanesthetic consultation and signed a consent form for the procedure. Anticoagulation Protocols (Pre and Postoperative) In the RIV group, patients received single-dose rivaroxaban after dinner, 20 mg or 15 mg, according to creatinine clearance, greater than 50 mL/min/m 2 or less, respectively, for 3 or more weeks before the procedure. The last dose was given on the night before the procedure and the next dose on the same day of the procedure, at least 4 hours after sheath removal and medical evaluation. In the control group, patients received oral warfarin under fasting condition to maintain the INR between 2 and 3.5 for at least 3 weeks before the procedure. The INR was checked the day before the procedure. The first dose after ablation was given on the same day or on the following day, depending on the new INR measurement and medical evaluation. All patients were submitted to transesophageal echocardiography (TEE) the day before the procedure to exclude intracavitary thrombi. The immediate postoperative (PO) (first 12 hours) was performed in a cardiological intensive care unit. Procedure The procedures were performed under general anesthesia after 8 hours of fasting. Suspension of antiarrhythmic drugs was decided individually, based on the clinical picture. Routine electrocardiogram, noninvasive blood pressure and esophageal temperature were monitored. The procedures consisted of ipsilateral and antral circumferential isolation of the PVs guided by electroanatomic mapping (Ensite/NAVX System, versions 4.1 and 5.0 – St. Jude Medical/Abbott) and portable fluoroscopy in both groups. Additional ablation techniques, such as linear ablation and complex fractional atrial electrograms (CFAE), were performed in some cases according to the operator’s preference, usually in cases of persistent and long-standing persistent AF. Cavo‑tricuspid isthmus (CTI) ablation was Figure 1 – Study flowchart. OAC = oral anticoagulant; WFR: warfarin; DOAC: direct acting oral anticoagulants; RIV: rivaroxaban; INR: International Normalized Ratio. AF ablation Uninterrupted OACs 357 pts 329 pts WFR 177 pts Excluded INR < 2 ou > 3.5 = 67 pts Excluded Other DOACs Uso Interrupto = 22 pts Excluded 28 pts (2 nd procedure) WFR 110 pts RIV 130 pts DOAC 152 pts 436