ABC | Volume 114, Nº3, March 2020

Short Editorial Cardoso & D’Avila Uninterrupted DOACs in AF Ablation Arq Bras Cardiol. 2020; 114(3):443-445 of 240 patients. This, however, should not be viewed as a limitation to the study, but rather as a testament to the safety of the procedure with both VKAs and DOACs. Similarly, two large randomized trials, VENTURE-AF (rivaroxaban) and RE-CIRCUIT (dabigatran), including 248 and 704 patients, respectively, acknowledged being underpowered for their primary endpoint of major bleeding. 4,5 Previously, apprehension regarding the lack of reversibility of DOACs limited widespread acceptance of this strategy. This concern has largely abated with the development of idarucizumab and andexanet alpha, reversal agents for dabigatran and factor Xa inhibitors, respectively. More importantly, perhaps, is that the overall strategy of uninterrupted DOACs has proven to be very safe with a low incidence of major bleeding events. In RE-CIRCUIT idarucizumab, although it was available, was not required in any of the 317 patients who underwent catheter ablation while on uninterrupted dabigatran, which included a dose administered on the morning of ablation. 5 In a pooled analysis of 14 patients with cardiac tamponade from 3 randomized trials of uninterrupted DOACs vs. VKAs, all underwent pericardiocentesis; 12 received protamine; and 2 (in the VKA group) received prothrombin complex concentrate. None received a direct DOAC reversal agent. 6 Bleeding events can also be prevented by meticulous attention to hemostasis. The use of a figure-of-eight suture for venous closure in patients who are fully anticoagulated at the end of the procedure also has the potential to decrease hematoma formation and shorten bedrest duration after catheter ablation. 7 This hemostatic suture may obviate the need for protamine reversal, extending therapeutic anticoagulation during the hours following the procedure. Whether this technique further reduces the (already low) thromboembolic risk with an acceptable incidence of bleeding events warrants further investigation. Finally, it is important to highlight the distinction between a truly uninterrupted strategy, where the DOAC is given pre- procedurally at the usual time and dose and an alternative minimally interrupted strategy, where 1 or 2 doses of the DOAC are held prior to catheter ablation. In both strategies, the DOAC is typically resumed at a minimum of 4 hours after femoral venous sheath removal. This is a particular dilemma with twice-daily agents, where a decision has to be made about the morning DOAC dose on the day of ablation; it is less of a concern with once-daily options, such as rivaroxaban, where the drug can be administered uninterruptedly in the evening prior to catheter ablation, without requiring a morning dose. In the ABRIDGE-J trial, 504 patients scheduled for AF catheter ablation were randomized to minimally interrupted dabigatran (holding 1 to 2 pre-procedure doses) or uninterrupted VKAs. There were no thromboembolic events in the 220 patients who underwent ablation in the dabigatran group. Minimally interrupted dabigatran was associated with a lower incidence of major bleeding (1.4%) as compared to uninterrupted VKAs (5%). 8 It should be emphasized, however, that while there is robust and consistent data supporting a strategy of uninterrupted DOACs for anticoagulation in patients undergoing AF catheter ablation, the use of a minimally interrupted strategy has neither been extensively studied nor directly compared to uninterrupted DOAC use in large randomized studies. In conclusion, studies have demonstrated that uninterrupted anticoagulation with DOACs for patients undergoing AF catheter ablation is effective in the prevention of periprocedural thromboembolic events (< 1%). This strategy also has a low risk of major bleeding events, comparable to or lower than bleeding events with uninterrupted VKAs. Prospective studies in the field will hopefully investigate mechanical approaches to minimize bleeding events and evaluate the efficacy and safety of a minimally interrupted DOAC strategy. Until then, the use of uninterrupted DOACs should be strongly favored as the preferred anticoagulation option for patients undergoing AF catheter ablation. The authors should be congratulated for their initiative and well-conducted study. 1. Di Biase L, Burkhardt JD, Santangeli P, Mohanty P, Sanchez JE, Horton R, et al. Periprocedural stroke and bleeding complications in patients undergoing catheter ablation of atrial fibrillation with different anticoagulation management: results from the Role of Coumadin in Preventing Thromboembolism in Atrial Fibrillation (AF) Patients Undergoing Catheter Ablation (COMPARE)randomizedtrial.Circulation.2014;129(25):2638-44. 2. Silva MA, Futuro GMC, Merçon ES, Vasconcelos D, Agrizzi RS, Elias Neto J, et al. Safety of Catheter Ablation of Atrial Fibrillation Under Uninterrupted Rivaroxaban Use. Arq Bras Cardiol. 2020; 114(3): 435-442. 3. Cardoso R, Knijnik L, Bhonsale A, Miller J, Nasi G, RiveraM, et al. An updated meta-analysis of novel oral anticoagulants versus vitamin K antagonists for uninterrupted anticoagulation in atrial fibrillation catheter ablation. Heart Rhythm. 2018;15(1):107-15. 4. Cappato R, Marchlinski FE, Hohnloser SH, Naccarelli GV, Xiang J,Wilber DJ, et al., and Investigators V-A. Uninterrupted rivaroxaban vs. uninterrupted vitamin K antagonists for catheter ablation in non-valvular atrial fibrillation. Eur Heart J. 2015;36(:1805-11. 5. Calkins H, Willems S, Gerstenfeld EP, Verma A, Schilling R, Hohnloser SH, et al., and Investigators R-C. Uninterrupted Dabigatran versus Warfarin for Ablation in Atrial Fibrillation. N Engl J Med. 2017;376(17):1627-36. 6. Cardoso R, Willems S, Gerstenfeld EP, Verma A, Schilling R, Hohnloser SH,et al. Uninterrupted anticoagulation with non-vitamin K antagonist oral anticoagulants in atrial fibrillation catheter ablation: Lessons learned from randomized trials. Clin Cardiol. 2019;42(1):198-205. 7. Lakshmanadoss U, WongWS, Kutinsky I, KhalidMR, Williamson B , Haines DE. Figure-of-eight suture for venous hemostasis in fully anticoagulated patients after atrial fibrillation catheter ablation. Indian Pacing Electrophysiol J. 2017;17(5):134-9. 8. Nogami A, Harada T, Sekiguchi Y, Otani R, Yoshida Y, Yoshida K, et al. , and Investigators A-J. Safety and Efficacy of Minimally Interrupted Dabigatran vs Uninterrupted Warfarin Therapy in Adults Undergoing Atrial Fibrillation Catheter Ablation: A Randomized Clinical Trial. JAMA Netw Open. 2019;2(4):e191994 References 444