ABC | Volume 110, Nº2, February 2018

Original Article Uninterrupted Use of Oral Anticoagulants for the Ablation of Atrial Flutter: A Single Center Cohort of 154 Patients Tiago Luiz Luz Leiria, Alexandre Kreling Medeiros, Eduardo Dytz Almeida, Antonio Lessa Gaudie Ley, Catarine Benta Lopes dos Santos, Roberto Toffani Sant’Anna, Marcelo Lapa Kruse, Leonardo Martins Pires, Gustavo Glotz de Lima Instituto de Cardiologia / Fundação Universitária de Cardiologia – IC/FUC, Porto Alegre, RS – Brazil Mailing Address: Tiago Luiz Luz Leiria Av. Princesa Isabel, 370. Postal Code 90620-000, Santana, Porto Alegre, RS – Brazil E-mail: pesquisa.leiria@gmail.com , editoracao-pc@cardiologia.org.br Manuscript received April 25, 2017, revised manuscript July 17, 2017, accepted August 09, 2017 DOI: 10.5935/abc.20180001 Abstract Background: The uninterrupted use of oral anticoagulation (OAC) with vitamin K antagonists (VKAs) for electrophysiology procedures has been more and more recommended. The clinical practice in our service recommends the continuous use of these drugs for atrial flutter ablation. There is little evidence as to the uninterrupted use of non-vitamin K antagonist oral anticoagulants (NOACs) in this scenario. Objective: To compare the rates of complications related with the uninterrupted use of different types of oral anticoagulants in patients referred to atrial flutter (AFL) ablation. Methods: Historical, single-center cohort of ablation procedures by AFL conducted from November 2012 to April 2016. The primary outcome was the occurrence of hemorrhagic or embolic complication during the procedure. The secondary outcome was the occurrence of stroke or transient ischemic attack (TIA) in follow-up. The statistical significance level was 5%. Results: There were 288 ablations per AFL; 154 were carried out with the uninterrupted use of OAC (57.8% with VKA and 42.2% with NOAC). Mean age was 57 ± 13 years. The rate of hemorrhagic complication during the procedure was 3% in each group (p = NS). The rate of stroke/TIA was, respectively, of 56/1,000 people-year in the VKA group against zero/1,000 people-year in the NOAC group (p = 0.02). Conclusion: In our population there were no hemorrhagic complications regarding the procedure of OAC use uninterruptedly, including NOACs. There was higher occurrence of stroke/TIA in the follow-up of the group of patients undergoing VKAs; however, this difference may not only be a result of the type of OAC used. (Arq Bras Cardiol. 2018; 110(2):151-156) Keywords: Anticoagulants; Vitamin K; Catheter Ablation; Atrial Flutter; Thromboembolism. Introduction The guidelines of the oral anticoagulant therapy 1 recommend the suspension of these medications and the performance of heparin bridging, at the conduction of a wide range of invasive Cardiology procedures. Recently, the new classes of non‑vitamin K antagonist oral anticoagulants (NOACs: rivaroxaban, apixaban, dabigatran and edoxaban) has proven to be effective to prevent the thromboembolic events in patients with atrial fibrillation (AF) and atrial flutter (AFL). 2 The catheter ablation for AFL is a highly successful procedure in the reversion for the sinus rhythm. 3,4 These cases require at least four weeks of anticoagulation before the procedure, as well as in electrical cardioversions, for the prevention of strokes or thromboembolic phenomena that can occur after the reversion of AFL to the sinus rhythm. 5 Studies show that the use of NOACs seems to be safe in the prevention of these thromboembolic phenomena, for the reversion to the sinus rhythm. 6,7 After the ablation, the use of anticoagulant is recommended for all patients for at least one month after the reversion to the sinus rhythm. 5 The uninterrupted use of oral anticoagulant for AF procedures has proven to be safe 8,9 , and our institution adopts such a recommendation also for patients with AFL. Therefore, in this scenario, there are few studies carried out in Brazil. The main objective of this study was to demonstrate the safety of the uninterrupted use of anticoagulation during flutter ablation, comparing the patients using NOACs with the vitamin K antagonists (VKAs). More specifically, we assessed the rate of hemorrhagic complications, as well as the occurrence of thromboembolic events throughout follow-up. Methods Our study is a historical cohort that includes the procedures of ablation for AFL carried out in our Electrophysiology service (Instituto de Cardiologia Fundação Universitária de Cardiologia do Rio Grande do Sul). Of the 5,506 procedures conducted between November 2012 and April 2016, 288 (5.2%) 151