Feasibility and safety of uninterrupted dabigatran therapy in patients undergoing ablation for atrial fibrillation

Effect of uninterrupted dabigatran or rivaroxaban on achieving ideal activated clotting time to heparin response during catheter ablation in patients with atrial fibrillation

BACKGROUND

Uninterrupted use of oral anticoagulants before atrial fibrillation (AF) ablation can reduce the incidence of perioperative thromboembolic events. However, the effect of new oral anticoagulants on activated clotting time (ACT) in response to heparin during AF ablation in Chinese populations remains unknown. The aim of the present retrospective study was to investigate the value of ACTs in response to intraoperative heparin administration in patients using dabigatran or rivaroxaban.

METHODS

From January 2018 to December 2021, a total of 173 patients undergoing AF ablation were included in the study, in which 101 patients were treated with dabigatran, 72 patients were treated with rivaroxaban. The intraoperative ACT values were examined in both groups. The incidence of periprocedural complications was evaluated.

RESULTS

Initial heparin dosage (88 ± 19 U/kg vs. 78 ± 27 U/kg, P < 0.05), total heparin dosage (137 ± 41 U/kg vs. 106 ± 52 U/kg, P < 0.05) during the ablation procedure were higher in the dabigatran group than those in the rivaroxaban group. Mean ACT (280 ± 36 s vs. 265 ± 30 s, P < 0.05), and the percentage of ACTs within the therapeutic range (250-350 s) (74% ± 26% vs. 60% ± 29%, P < 0.05) were significantly lower in the dabigatran group than those in the rivaroxaban group, particularly in male patients. Furthermore, the average time of achieving the target ACT (250-350 s) was also found longer in the dabigatran group (P < 0.05) as compared with the rivaroxaban group. No significant difference was found in the incidence of periprocedural complications between the two groups.

CONCLUSIONS

The anticoagulant effect of uninterrupted rivaroxaban therapy appears to be more stable and efficient than dabigatran administration during catheter ablation in patients with AF.

Changes in plasma concentrations of edoxaban and coagulation biomarkers according to thromboembolic risk and atrial fibrillation type in patients undergoing catheter ablation: Subanalysis of KYU-RABLE

BACKGROUND

Catheter ablation (CA) for atrial fibrillation (AF) can be associated with a risk of thromboembolism and bleeding. We recently demonstrated that uninterrupted edoxaban with one dose delayed on the CA procedural day is associated with a low risk of periprocedural complications. Previous reports have indicated that some specific subgroups of patients undergoing CA have an increased risk of bleeding and thromboembolic complications. This subanalysis of the KYU-RABLE study assessed the changes in plasma concentrations of edoxaban and coagulation biomarkers during the periprocedural period of CA in subgroups stratified by the risk of thromboembolism assessed by CHADS2 score (<2 or ≥2) and AF type (paroxysmal AF [PAF] or non-PAF).

METHODS

We evaluated changes in plasma concentrations of edoxaban and coagulation biomarkers (D-dimer and prothrombin fragment F1+2), by subgroup, during the periprocedural period of CA. Measurements were made prior to CA (procedure day).

RESULTS

This subanalysis evaluated data from 343 patients with CHADS2 score <2 and 134 patients with CHADS2 score ≥2, and from 280 patients with PAF and 197 patients with non-PAF. Plasma edoxaban concentration decreased with time on the day of CA, while plasma concentrations of coagulation biomarkers remained unchanged. No significant differences were observed according to CHADS2 score or type of AF.

CONCLUSIONS

The changes in plasma concentrations of edoxaban and coagulation biomarkers in each subgroup were similar to those of the whole analysis, regardless of the thromboembolic risk (CHADS2 <2 or ≥2) or AF type (PAF or non-PAF).

Safety and efficacy of uninterrupted treatment with edoxaban or warfarin during the peri-procedural period of catheter ablation for atrial fibrillation

BACKGROUND

The real-world safety and efficacy of uninterrupted anticoagulation treatment with edoxaban (EDX) or warfarin (WFR) during the peri-procedural period of catheter ablation (CA) for atrial fibrillation (AF) are yet to be investigated.

METHODS

We conducted a two-center experience, observational study to retrospectively investigate consecutive patients who underwent CA for AF and received EDX or WFR. We examined the incidence of thromboembolic and bleeding complications during the peri-procedural period.

RESULTS

The EDX and WFR groups included 153 and 103 patients, respectively (total: 256 patients). Demise or thromboembolic events did not occur in either of the groups. The incidence of major bleeding in the EDX and WFR groups was 0.7% and 2.9%, respectively. The total incidence of major/minor bleeding in the EDX and WFR groups was 7.8% and 8.7%, respectively. Of note, the incidence of bleeding complications in the uninterrupted WFR strategy group was markedly high in patients with an estimated glomerular filtration rate (eGFR) <30 (75%) or a HAS-BLED score ≥3 (60%). Patients with eGFR ≥30 and a HAS-BLED score ≤2 had a lower incidence of bleeding (<10%), regardless of the administered anticoagulation drug (EDX or WFR).

CONCLUSIONS

This study confirmed the safety and efficacy of uninterrupted anticoagulation therapy using EDX or WFR in real-world patients undergoing CA for AF. Patients with severely impaired renal function and/or a higher bleeding risk during uninterrupted therapy with WFR were at a prominent risk of bleeding. Therefore, particular attention should be paid in the treatment of these patients.

Perioperative Safety and Efficacy of Different Anticoagulation Strategies With Direct Oral Anticoagulants in Pulmonary Vein Isolation: A Meta-Analysis

OBJECTIVES

The purpose of this study was to evaluate the safety and efficacy of uninterrupted and interrupted direct oral anticoagulant (DOAC) administration in patients undergoing pulmonary vein isolation (PVI).

BACKGROUND

The optimal periprocedural management of DOACs in patients undergoing PVI is not well defined, and different strategies are used.

METHODS

A systematic search of PubMed/MEDLINE, Ovid/MEDLINE, and EMBASE was performed. Three strategies for periprocedural DOAC administration were considered: uninterrupted, mildly interrupted (<12 h), and interrupted (≥12 h). Primary endpoints were major bleeding (MB) and thromboembolic (TE) complications; pooled weighted mean incidence (WMI) was calculated using a random-effects model. A secondary endpoint was the WMI of overall bleeding (OB).

RESULTS

The analysis included 43 studies for a total of 8,362 patients. DOACs showed similar safety and efficacy in the 3 subgroups. The WMI of MB was 1.02%, 1.49%, and 1.17% for the uninterrupted, mildly interrupted, and interrupted strategy, respectively; the WMI of TE complications was 0.16%, 0.46%, and 0.49% for the uninterrupted, mildly interrupted, and interrupted strategy, respectively, with no heterogeneity. OB appeared to be higher in uninterrupted (6.33%) and mildly interrupted (8.62%) groups compared with the interrupted (3.53%), with substantial heterogeneity among studies. No interaction was found between the incidence of MB and TE complications and different DOACs.

CONCLUSIONS

In patients undergoing PVI, these 3 anticoagulation strategies may have similar safety and efficacy in terms of MB and TE complications. OB appears to be higher in uninterrupted and mildly interrupted strategies compared with the interrupted strategy. No substantial differences were observed among DOACs regarding the incidence of MB and TE complications.

Safety and efficacy of nonvitamin K antagonist oral anticoagulants during catheter ablation of atrial fibrillation: A systematic review and meta-analysis

AIMS

Catheter ablation for atrial fibrillation (AF) is associated with a transitory increase in the risk of both thromboembolic and bleeding events. Evidence on the use of nonvitamin K antagonist oral anticoagulants (NOACs) in patients undergoing AF ablation mostly comes from small observational studies, underpowered to detect differences in clinical outcomes between NOACs and vitamin K antagonists (VKAs) treated patients. This updated meta-analysis aimed to determine the safety and efficacy of periprocedural anticoagulation with NOACs compared with VKAs in AF patients undergoing catheter ablation.

METHODS

We searched MEDLINE, Cochrane library, and web sources for randomized and observational studies comparing periprocedural treatment with NOACs and VKAs in patients undergoing AF ablation. The primary safety endpoint was major bleeding events, and the primary efficacy endpoint was thromboembolic events (a composite of systemic thromboembolism, transient ischemic attack, and stroke).

RESULTS

A total of 29 studies with 12 644 patients were included in the meta-analysis. Overall, patients on NOACs had a significantly lower risk of major bleeding compared to VKAs either in observational studies (Peto OR 0.68; 95% CI: 0.48-0.95; P = 0.022; I²  = 20%) or in RCTs (Peto OR 0.30; 95% CI: 0.14-0.62; P = 0.001; I²  = 28%). Uninterrupted NOACs reduced the risk of major bleeding when compared to uninterrupted VKAs (Peto OR 0.66; 95% CI: 0.45-0.96; P = 0.028; I²  = 1%), similarly, interrupted NOACs lowered the risk of major bleeding compared to interrupted VKAs (Peto OR 0.29; 95% CI: 0.13-0.66; P = 0.003; I²  = 0%; P_interaction  = 0.076). The rate of thromboembolic complications was very low and did not significantly differ between the study groups either in observational studies (Peto OR 0.91; 95% CI: 0.49-1.67; P = 0.755; I²  = 0%) or in RCTs (Peto OR 0.14; 95% CI: 0.01-1.30; P = 0.083; I²  = 0%).

CONCLUSIONS

Use of NOACs compared to VKAs significantly reduced the risk of bleeding in patients with AF ablation. Similarly, the risk of bleeding was lower with uninterrupted NOACs than with uninterrupted VKAs, and with interrupted NOACs than with interrupted VKAs. The rate of thromboembolic complications was extremely low in both study groups without any differences.

Choosing a particular oral anticoagulant and dose for stroke prevention in individual patients with non-valvular atrial fibrillation: part 1

Patients with atrial fibrillation (AF) have a high risk of stroke and mortality, which can be considerably reduced by oral anticoagulants (OAC). Recently, four non-vitamin-K oral anticoagulants (NOACs) were compared with warfarin in large randomized trials for the prevention of stroke and systemic embolism. Today's clinician is faced with the difficult task of selecting a suitable OAC for a patient with a particular clinical profile or a particular pattern of risk factors and concomitant diseases. We reviewed analyses of subgroups of patients from trials of vitamin K antagonists vs. NOACs for stroke prevention in AF with the aim to identify patient groups who might benefit from a particular OAC more than from another. In the first of a two-part review, we discuss the choice of NOAC for stroke prevention in the following subgroups of patients with AF: (i) stable coronary artery disease or peripheral artery disease, including percutaneous coronary intervention with stenting and triple therapy; (ii) cardioversion, ablation and anti-arrhythmic drug therapy; (iii) mechanical valves and rheumatic valve disease, (iv) patients with time in therapeutic range of >70% on warfarin; (v) patients with a single stroke risk factor (CHA2DS2VASc score of 1 in males, 2 in females); and (vi) patients with a single first episode of paroxysmal AF. Although there are no major differences in terms of efficacy and safety between the NOACs for some clinical scenarios, in others we are able to suggest that particular drugs and/or doses be prioritized for anticoagulation.

Uninterrupted Direct Oral Anticoagulant and Warfarin Administration in Elderly Patients Undergoing Catheter Ablation for Atrial Fibrillation: A Comparison With Younger Patients

OBJECTIVES

The goal of this study was to evaluate the efficacy and safety of uninterrupted direct oral anticoagulant (DOAC) use and uninterrupted warfarin administration in elderly patients undergoing catheter ablation for atrial fibrillation (AF).

BACKGROUND

There is limited knowledge regarding the uninterrupted use of oral anticoagulant agents in elderly patients undergoing catheter ablation for AF.

METHODS

This retrospective study included 2,164 patients (n = 325 ≥75 years of age and n = 1,839 <75 years of age) who underwent catheter ablation for AF. All the patients received uninterrupted oral anticoagulant agents during the procedure. We investigated the occurrences of periprocedural events and compared these between the DOAC and warfarin groups of the elderly and younger groups.

RESULTS

Major bleeding events (3.1% vs. 1.3%; p = 0.023) and minor bleeding events (9.2% vs. 5.0%; p = 0.002), except for thromboembolic events (0% vs. 0.8%; p = 0.248), were significantly higher in the elderly group than in the younger group. No significant differences in thromboembolic and bleeding events were found between the DOAC and warfarin groups of both the elderly and younger groups. Adverse complications did not differ between the groups after adjustment using propensity score matching analysis. Multivariate analysis revealed that lower body weight (odds ratio: 0.96; p = 0.010) and antiplatelet drug use (odds ratio: 2.21; p = 0.039) were independent predictors of adverse events in the elderly group.

CONCLUSIONS

The periprocedural bleeding risk during the use of uninterrupted oral anticoagulants was higher in the elderly group than in the younger group. This area needs more attention for these patients in whom caution is required.

Periprocedural Management of Direct Oral Anticoagulants Surrounding Cardioversion and Invasive Electrophysiological Procedures

Supplemental Digital Content is available in the text.

As direct oral anticoagulants (DOACs) have demonstrated favorable efficacy and safety outcomes compared with vitamin K antagonists for the treatment and prevention of venous thromboembolism and the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation, their role in the management of anticoagulation during electrophysiological procedures continues to evolve. At present, guidelines are limited regarding specific recommendations for the use of DOACs in these clinical settings. Here, we review available data regarding the risks and benefits associated with various periprocedural anticoagulation management approaches when patients receiving DOACs undergo electrophysiologic procedures including cardioversion, ablation, and device implantation. This discussion is intended to provide clinicians with an overview of available evidence and best practices to minimize the risk of both thromboembolic and bleeding events in the periprocedural setting.

[S1 guideline - Austrian consensus for anticoagulation in the context of atrial fibrillation ablation]

In summary, uninterrupted oral antikoagulation can be recommended, with different recommendation classes and levels of evidence, for both, VKA and NOAC therapy, in the framework of PVI. Even with low CHA₂DS₂ VASc scores, OAK is indicated 3-4 weeks before and 8 weeks after the procedure. Periinterventional bridging with heparins should be avoided due to increased bleeding events.The present Consensus provides recommendations on the current state of knowledge and has been prepared exclusively by members of the Rhythmology Working Group of the Austrian Cardiological Society who have great practical experience in catheter ablation and peri-interventional OAK in patients with atrial fibrillation. Publication of new randomized and controlled studies on the subject are expected in the coming months, so that there will certainly be changes in the recommendations. The Rhythmology Working Group of the Austrian Cardiological Society will strive to keep this S1 guideline regularly up to date. We hope that this consensus is used to increase the safety for patients undergoing PVI and to provide physicians with a homogeneous approach in Austria.

Comparison of uninterrupted anticoagulation with dabigatran etexilate or warfarin in the periprocedural period for atrial fibrillation catheter ablation: Results of the Japanese subgroup of the RE-CIRCUIT trial

Background

There are limited data on uninterrupted anticoagulation with direct oral anticoagulants during catheter ablation for atrial fibrillation (AF), particularly in Japan. We planned a subgroup analysis of the RE-CIRCUIT study, comparing the use of uninterrupted dabigatran therapy with warfarin therapy during catheter ablation among the Japanese subgroup and with that in the total population.

Methods

The RE-CIRCUIT study utilized a prospective, randomized, open-label, blinded endpoint design, and the primary endpoint was the incidence of major bleeding events (MBEs). Patients were randomized to uninterrupted dabigatran 150 mg twice daily or warfarin. In this study, we analyzed the results in Japanese patients.

Results

Of 704 enrolled patients in the study, 112 Japanese patients were randomized to dabigatran (n = 65) or warfarin (n = 47). MBEs were experienced by two patients: one in the dabigatran group (1.6%, cardiac tamponade) and one in the warfarin group (2.2%, groin hematoma) (risk difference vs warfarin -0.6%; 95% CI -5.8, 4.7). Within the Japanese subgroup, there were no thromboembolic events in both groups.

Conclusion

While not designed to show statistical difference between two treatment groups, our results from the Japanese subgroup supported those from the overall population. Furthermore, this study provided clinical information regarding MBE, especially cardiac tamponade, in Japanese patients.

How safe are NOACs compared with phenprocoumon after pulmonary vein isolation with the cryoballoon technique using purse-string suture closure?

INTRODUCTION

The aim of this observational study was to compare the postprocedural incidence of bleeding and thromboembolic complications associated with novel oral anticoagulants (NOACs) with that of interrupted and continuous phenprocoumon after pulmonary vein isolation (PVI) using a purse-string suture (PSS) closure of the puncture site.

METHODS AND RESULTS

Consecutive patients who had undergone PVI via cryoballoon ablation were divided into the following groups: (1) interrupted phenprocoumon with heparin bridging (n=101), (2) continuous phenprocoumon targeting an internationally normalized ratio>2 (n=70), and (3) NOACs without bridging that were restarted 2-4h after the procedure (n=185). Protamine was not administered after venous closure with PSS at the end of the procedure. The total complication rate was significantly lower in group 3 than in groups 1 and 2 (1.62% vs. 6.93% vs. 7.14%, p=0.04). The hospital costs were lower and the hospital stay length was significantly shorter (4484±3742 vs. 6082±4044 Euro vs. 4908±2925, p=0.03; 1.94±1.67 vs. 2.70±1.80 vs. 2.19±1.30days, p<0.01). No thromboembolic event occurred. Vascular complications were the most common complications noted (80%). The occurrence of any complication led to a significantly longer hospital stay (5 vs. 2days, p<0.01) and higher costs (10,052±6241 Euro vs. 4747±3447, p<0.01). The vascular complication rate after PSS was independent of intraprocedural heparin dosage and activated clotting time.

CONCLUSIONS

NOACs have a lower complication rate and appear to be safer in this setting than phenprocoumon. The hospital costs and hospital stay length after PVI was significantly reduced in patients treated with NOACs compared with phenprocoumon.

Renal function and risk of stroke and bleeding in patients undergoing catheter ablation for atrial fibrillation: Comparison between uninterrupted direct oral anticoagulants and warfarin administration

BACKGROUND

The effect of uninterrupted oral anticoagulant use in patients with chronic kidney disease (CKD) during catheter ablation for atrial fibrillation (AF) is not fully understood.

OBJECTIVE

The present study aimed to evaluate the safety and efficacy of periprocedural uninterrupted direct oral anticoagulant (DOAC) use compared with those of uninterrupted warfarin use in patients undergoing catheter ablation for AF stratified by various renal function groups.

METHODS

A total of 2091 patients were retrospectively included in this study. The study population was divided into 4 groups: creatinine clearance level ≥80 mL/min (n = 1086), 50-79 mL/min (n = 774), 15-49 mL/min (n = 209), and <15 mL/min (n = 22). We investigated periprocedural complications and compared them between uninterrupted DOAC and warfarin groups.

RESULTS

There was no significant difference in thromboembolic events among the 4 groups (0.6%, 0.6%, 1.0%, and 0%, respectively; P = .792). However, major bleeding events (0.9%, 1.4%, 4.8%, and 4.5%; P < .001) and minor bleeding events (4.1%, 6.1%, 11.5%, and 13.6%; P < .001) primarily occurred in patients with CKD. The rate of periprocedural complications in the DOAC group was similar to that in the warfarin group for each renal function category. Adverse events did not differ after adjustment using propensity score-matched analysis. Multivariate analysis showed that lower body weight, antiplatelet drug use, initial ablation session, and CKD were independent predictors of adverse events.

CONCLUSION

The periprocedural bleeding risk was increased in patients with CKD. Uninterrupted DOAC and warfarin administration during catheter ablation for AF in patients with CKD is feasible and effective.

Perioperative management of patients on direct oral anticoagulants

Direct oral anticoagulants (DOACs) have been licensed worldwide for several years for various indications. Each year, 10-15% of patients on oral anticoagulants will undergo an invasive procedure and expert groups have issued several guidelines on perioperative management in such situations. The perioperative guidelines have undergone numerous updates as clinical experience of emergency management has increased and perioperative studies including measurement of residual anticoagulant levels have been published. The high inter-patient variability of DOAC plasma levels has challenged the traditional recommendation that perioperative DOAC interruption should be based only on the elimination half-life of DOACs, especially before invasive procedures carrying a high risk of bleeding. Furthermore, recent publications have highlighted the potential danger of heparin bridging use when DOACs are stopped before an invasive procedure. As antidotes are progressively becoming available to manage severe bleeding or urgent procedures in patients on DOACs, accurate laboratory tests have become the standard to guide their administration and their actions need to be well understood by clinicians. This review aims to provide a systematic approach to managing patients on DOACs, based on recent updates of various perioperative guidance, and highlighting the advantages and limits of recommendations based on pharmacokinetic properties and laboratory tests.

Uninterrupted Dabigatran versus Warfarin for Ablation in Atrial Fibrillation

BACKGROUND

Catheter ablation of atrial fibrillation is typically performed with uninterrupted anticoagulation with warfarin or interrupted non-vitamin K antagonist oral anticoagulant therapy. Uninterrupted anticoagulation with a non-vitamin K antagonist oral anticoagulant, such as dabigatran, may be safer; however, controlled data are lacking. We investigated the safety of uninterrupted dabigatran versus warfarin in patients undergoing ablation of atrial fibrillation.

METHODS

In this randomized, open-label, multicenter, controlled trial with blinded adjudicated end-point assessments, we randomly assigned patients scheduled for catheter ablation of paroxysmal or persistent atrial fibrillation to receive either dabigatran (150 mg twice daily) or warfarin (target international normalized ratio, 2.0 to 3.0). Ablation was performed after 4 to 8 weeks of uninterrupted anticoagulation, which was continued during and for 8 weeks after ablation. The primary end point was the incidence of major bleeding events during and up to 8 weeks after ablation; secondary end points included thromboembolic and other bleeding events.

RESULTS

The trial enrolled 704 patients across 104 sites; 635 patients underwent ablation. Baseline characteristics were balanced between treatment groups. The incidence of major bleeding events during and up to 8 weeks after ablation was lower with dabigatran than with warfarin (5 patients [1.6%] vs. 22 patients [6.9%]; absolute risk difference, -5.3 percentage points; 95% confidence interval, -8.4 to -2.2; P<0.001). Dabigatran was associated with fewer periprocedural pericardial tamponades and groin hematomas than warfarin. The two treatment groups had a similar incidence of minor bleeding events. One thromboembolic event occurred in the warfarin group.

CONCLUSIONS

In patients undergoing ablation for atrial fibrillation, anticoagulation with uninterrupted dabigatran was associated with fewer bleeding complications than uninterrupted warfarin. (Funded by Boehringer Ingelheim; RE-CIRCUIT ClinicalTrials.gov number, NCT02348723 .).

Influence of periprocedural anticoagulation strategies on complication rate and hospital stay in patients undergoing catheter ablation for persistent atrial fibrillation

BACKGROUND

The use of non-vitamin K antagonists (NOACs), uninterrupted (uVKA) and interrupted vitamin K antagonists (iVKA) are common periprocedural oral anticoagulation (OAC) strategies for atrial fibrillation (AF) ablation. Comparative data on complication rates resulting from OAC strategies for solely persistent AF (persAF) undergoing ablation are sparse. Thus, we sought to determine the impact of these OAC strategies on complication rates among patients with persAF undergoing catheter ablation.

METHODS

Consecutive patients undergoing persAF ablation were included. Depending on preprocedural OAC, three groups were defined: (1) NOACs (paused 48 h preablation), (2) uVKA, and (3) iVKA with heparin bridging. A combined complication endpoint (CCE) composed of bleeding and thromboembolic events was analyzed.

RESULTS

Between 2011 and 2014, 1440 persAF ablation procedures were performed in 1092 patients. NOACs were given in 441 procedures (31 %; rivaroxaban 57 %, dabigatran 33 %, and apixaban 10 %), uVKA in 488 (34 %), and iVKA in 511 (35 %). Adjusted CCE rates were 5.5 % [95 % confidence interval (CI) (3.1-7.8)] in group 1 (NOACs), 7.5 % [95 % CI (5.0-10.1)] in group 2 (uVKA), and 9.9 % [95 % CI (6.6-13.2)] in group 3. Compared to group 1, the combined complication risk was almost twice as high in group 3 [odd's ratio (OR) 1.9, 95 % CI (1.0-3.7), p = 0.049)]. The major complication rate was low (0.9 %). Bleeding complications, driven by minor groin complications, are more frequent than thromboembolic events (n = 112 vs. 1, p < 0.0001).

CONCLUSIONS

Patients undergoing persAF ablation with iVKA anticoagulation have an increased risk of complications compared to NOACs. Major complications, such as thromboembolic events, are generally rare and are exceeded by minor bleedings.

Are Some Anticoagulants More Equal Than Others? - Evaluating the Role of Novel Oral Anticoagulants in AF Ablation

Left atrial ablation strategies are being increasingly performed as a Class 1 therapeutic indication for drug refractory paroxysmal atrial fibrillation (AF). Traditionally AF ablation has been performed with patients on uninterrupted warfarin therapy, however over the last few years, novel oral anticoagulants (NOACs) have emerged as attractive alternatives to warfarin in order to reduce stroke risk due to AF. NOACs are therefore increasingly being used instead of warfarin in the management of AF. There is also mounting evidence mainly in the form of small randomised studies and meta-analysis that have demonstrated that the use of NOACs for AF ablation is efficacious, safe and convenient. However the peri-procedural dosing protocols used in various studies especially in terms of whether NOAC use is interrupted or uninterrupted during AF ablation, have significant inter-operator and inter-institution variability. Currently there is also a lack of randomised controlled trials to validate the data obtained from meta-analyses. There is also evidence that use of NOACs may increase the requirement of unfractionated heparin during the procedure. This review article shall examine the currently available evidence-base, appraise the gaps in the current evidence and also underscore the need for larger randomised clinical trials in this rapidly developing field.

Network meta-analysis of efficacy and safety of competitive oral anticoagulants in patients undergoing radiofrequency catheter ablation of atrial fibrillation

PURPOSE

The aim of this network meta-analysis was to evaluate the comparative efficacy and safety of dabigatran, rivaroxaban, apixaban, interrupted vitamin K antagonist (I-VKA), and continuous VKA (C-VKA) in patients undergoing radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF).

METHODS

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials were searched to identify clinical trials comparing dabigatran, rivaroxaban, or apixaban with I-VKA or C-VKA, or against each other, in AF patients undergoing RFCA. A network meta-analysis was conducted to directly and indirectly compare the efficacy and safety of competitive anticoagulation regimens with a Bayesian random-effects model.

RESULTS

A total of 39 studies enrolling 27,766 patients were included. C-VKA demonstrated significant superiority over I-VKA in reducing thromboembolic events (risk difference [RD] -0.0068, 95 % confidence interval [CI] -0.0106 to -0.0032) and major bleeding complications (RD -0.0044, 95 % CI -0.0098 to -0.0006). Rivaroxaban compared with I-VKA was associated with a lower risk of thromboembolism (RD -0.0073, 95 % CI -0.0134 to -0.0012), being at the best ranking position among all of the compared anticoagulation regimens in terms of both the efficacy and safety. None of the remaining comparisons reached statistically significant difference in the rate of thromboembolism or major bleeding.

CONCLUSIONS

The present study suggests that C-VKA is superior to I-VKA for AF patients undergoing RFCA. Rivaroxaban is the highest probability to be the optimal alternative to C-VKA among the three non-VKA oral anticoagulants in AF ablation.

Meta-Analysis of Efficacy and Safety of New Oral Anticoagulants Compared With Uninterrupted Vitamin K Antagonists in Patients Undergoing Catheter Ablation for Atrial Fibrillation

Anticoagulation in catheter ablation (CA) of atrial fibrillation (AF) is of paramount importance for prevention of thromboembolic events, and recent studies favor uninterrupted vitamin K antagonists (VKAs). We aimed to compare the efficacy and safety of new oral anticoagulants (NOACs) to uninterrupted VKAs for anticoagulation in CA by performing a meta-analysis. PubMed, EMBASE, the Cochrane Library, and Clinicaltrials.gov databases were searched for studies comparing NOACs with uninterrupted VKAs in patients who underwent CA for AF from January 1, 2000, to August 31, 2015. Odds ratio (OR) and Peto's OR (POR) were used to report for event rates >1% and <1%, respectively. A total of 11,686 patients with AF who underwent CA in 25 studies were included in this analysis. There was no significant difference between NOACs and uninterrupted VKAs in occurrence of stroke or transient ischemic attacks (POR 1.35, 95% CI 0.62 to 2.94) and major bleeding (POR 0.87, 95% CI 0.58 to 1.31), which were consistent in subgroup analysis of interrupted and uninterrupted NOACs. A lower risk of minor bleeding was observed with NOACs (OR 0.80, 95% CI 0.65 to 1.00), and no major differences were observed for the risk of thromboembolic events, cardiac tamponade or pericardial effusion requiring drainage, and groin hematoma. NOACs, whether interrupted preprocedure or not, were associated with equal rates of stroke or TIA and major bleeding complications and less risk of minor bleeding compared with uninterrupted VKAs in CA for AF.