Prevention of venous thromboembolism in right heart-sided electrophysiological procedures: results of an European Heart Rhythm Association survey

Limited data are available regarding venous thromboembolism (VTE), specifically deep vein thrombosis (DVT) and pulmonary embolism (PE), following right-sided ablations and electrophysiological (EP) studies. Compared to left-sided procedures, no guidelines on antithrombotic management strategies for the prevention of DVT and PE are available. The main purpose of the present European Heart Rhythm Association (EHRA) survey is to report the current management of right-sided EP procedures, focusing on anticoagulation and prevention of VTE. An online survey was conducted using the EHRA infrastructure. A total of 244 participants answered a 19-items questionnaire on the periprocedural management of EP studies and right-sided catheter ablations. The right femoral vein is the most common access for EP studies and right-sided procedures. An ultrasound-guided approach is employed by more than 2/3 of respondents. Intravenous heparin is not commonly given by the majority of participants. About 1/3 of participants (34%) routinely prescribe VTE prophylaxis during (mostly aspirin and low molecular weight heparin) and 1/4 of respondents (25%) commonly prescribe VTE prophylaxis after discharge (mostly aspirin). Of note, respectively 13% and 9% of participants observed at least one DVT and one PE related to right-sided ablation or EP study within the last year in their center. The present survey shows that only a minority of operators routinely gives intraprocedural intravenous heparin and prescribes VTE prophylaxis after right-sided EP procedures. Compared to left-sided procedures like atrial fibrillation (AF) ablation, there are no consistent systematic antithrombotic management strategies.

Uninterrupted Direct Oral Anticoagulants Without a Change in Regimen for Catheter Ablation for Atrial Fibrillation Is an Acceptable Protocol

Background: In patients undergoing catheter ablation (CA) for atrial fibrillation (AF), the use of uninterrupted direct oral anticoagulants (DOACs) is the current protocol. This study evaluated bleeding complications following the uninterrupted use of 4 DOACs in patients undergoing CA for AF without any change in the dosing regimen. Moreover, we assessed differences between once- and twice-daily DOAC dosing in patients undergoing CA for AF who continued on DOACs without any change in the dosing regimen.

Methods and Results: This study was a retrospective single-center cohort study of consecutive patients. All patients continued DOACs without interruption or changes to the dosing schedule, even in the case of morning procedures. The primary endpoint was the incidence of major bleeding events within the first 30 days after CA. In all, 710 consecutive patients were included in the study. Bleeding complications were less frequent in the uninterrupted twice- than once-daily DOACs group. However, the incidence of cardiac tamponade across all DOACs was low (0.98%; 7/710), suggesting that uninterrupted DOACs without changes to the dosing regimen may be an acceptable strategy. The rate of total bleeding events, including minor bleeding (12/710; 1.6%), was also satisfactory.

Conclusions: Uninterrupted DOACs without any change in dosing regimen for patients undergoing CA for AF is acceptable. Bleeding complications may be less frequent in patients receiving DOACs twice rather than once daily.

Uninterrupted use of direct oral anticoagulants versus vitamin K antagonists for catheter ablation of atrial fibrillation with PVAC gold: incidence of silent cerebral microembolic events

BACKGROUND

Silent cerebral microembolic events (SCE) after duty-cycled ablation of atrial fibrillation using PVAC have been detected by cerebral magnet resonance imaging (MRI) in a substantial number of patients. The purpose of this study was to investigate if uninterrupted oral anticoagulation with non-vitamin K antagonists (NOACs) compared with vitamin K antagonists (VKA) affects the incidence of SCE after pulmonary vein isolation (PVI) using PVAC Gold.

METHODS

Eighty-four consecutive patients (62 ± 15 years, 58% male) undergoing a first PVI were prospectively enrolled. Of these, 42 were on VKA and 42 on uninterrupted NOAC treatment. An activated clotting time (ACT) ≥ 350 s was targeted for ablation.

RESULTS

Cerebral MRI the day after PVI revealed acute diffusion-weighted positive lesions in 11/42 (26%) VKA compared with 14/42 (33%) in NOAC patients (p = 0.634). No differences were found for lesion size, number of lesions/patient, and number of lesions indicating cerebral infarction (2.4% for VKA and 4.8% for NOAC patients). Seventy-five percent of NOAC patients with sporadic ACT levels < 300 s during PVI developed SCE compared with 22% of corresponding VKA patients (p = 0.030). VKA and NOAC subgroups with ACT ≥ 350 s had no reduced incidence of SCE compared with ACT 300-350 s.

CONCLUSIONS

A significant, but comparable, number of patients under uninterrupted anticoagulation with VKA or NOACs still experience SCE after PVAC Gold PVI. NOAC patients with sporadic subtherapeutic ACT levels during PVI are at the highest risk for SCE while permanent ACT levels ≥ 350 s did not further reduce the incidence of SCE in both groups.

Comparison of peri-procedural anticoagulation with rivaroxaban and apixaban during radiofrequency ablation of atrial fibrillation

Introduction

Prospective studies on rivaroxaban and apixaban have shown the safety and efficacy of direct anticoagulation agents (DOAC)s used peri-procedurally during radiofrequency ablation (RFA) of atrial fibrillation (AF). Studies comparing the two agents have not been performed.

Methods

Consecutive patients from a prospective registry who underwent RFA of AF between April 2012 and March 2015 and were on apixaban or rivaroxaban were studied. Clinical variables and outcomes were noted.

Results

There were a total of 358 patients (n = 56 on apixaban and n = 302 on rivaroxaban). There were no differences in baseline characteristics between both groups. The last dose of rivaroxaban was administered the night before the procedure in 96% of patients. In patients on apixaban, 48% of patients whose procedure was in the afternoon took the medication on the morning of the procedure. TIA/CVA occurred in 2 patients (0.6%) in rivaroxaban group with none in apixaban group (p = 0.4). There was no difference in the rate of pericardial effusion between apixaban and rivaroxaban groups [1.7% vs 0.6% (p = 0.4)]. Five percent of patients in both groups had groin complications (p = 0.9). In apixaban group, all groin complications were small hematomas except one patient who had a pseudoaneurysm (1.6%). One pseudo-aneurysm, 1 fistula and 3 large hematomas were noted in patients on rivaroxaban (1.7%) with the rest being small hematomas. DOACs were restarted post procedure typically 4 h post hemostasis.

Conclusions

Peri-procedural uninterrupted use of apixaban and rivaroxaban during AF RFA is safe and there are no major differences between both groups.

Cerebral thromboembolic risk in atrial fibrillation ablation: a direct comparison of vitamin K antagonists versus non-vitamin K-dependent oral anticoagulants

PURPOSE

Cerebral thromboembolic events are well-known complications of pulmonary vein isolation (PVI) and can manifest as stroke or silent cerebral embolic lesions. The aim of this study was to compare the incidence of cerebral embolic lesions (including silent cerebral embolism and stroke) after AF ablation in patients on vitamin K antagonists versus patients on non-vitamin K-dependent oral anticoagulants, and to identify corresponding clinical and procedural risk factors.

METHODS

A total of 421 patients undergoing PVI were prospectively included into the study. Of these, 43.7% were on VKA and 56.3% on NOAC treatment (dabigatran, rivaroxaban, apixaban, and edoxaban). In the NOAC group, 38% of patients had an interruption of anticoagulation for 24-36 h. All patients underwent pre- and postprocedural cerebral magnetic resonance imaging.

RESULTS

Periprocedural cerebral lesions occurred in 13.1% overall. Of these, three (0.7%) resulted in symptomatic cerebrovascular accidents and 52 (12.4%) in silent cerebral embolic lesions. Incidence of cerebral lesions was significantly higher in patients on NOAC compared with VKA (16% vs. 9.2%, respectively, p = 0.04), and in patients who had intraprocedural cardioversions compared with no cardivoersions (19.5% vs. 10.4%, respectively, p = 0.03). In multivariate analysis, both parameters were found to be independent risk factors for cerebral embolism. No significant difference between interrupted and uninterrupted NOAC administration could be detected.

CONCLUSIONS

In patients undergoing AF ablation, we identified the use of NOAC and intraprocedural cardioversion as independent risk factors for the occurrence of periprocedural cerebral embolic lesions.

Atrial Fibrillation Ablation: Indications and Techniques

PURPOSE OF REVIEW

Atrial fibrillation (AF) predisposes to embolic strokes and reduced quality of life. Ablation (catheter-based or surgically performed) can be employed to promote the maintenance of sinus rhythm in a carefully selected subset of patients with AF. The goal of this review is to discuss the indications and techniques for AF ablation, as well as post-procedural outcomes.

RECENT FINDINGS

Atrial fibrillation ablation improves quality of life in patients with atrial fibrillation although no clear reduction in stroke or overall mortality has been shown. Familiarity with the indications for AF ablation is important for all cardiologists, as is having a sound understanding of the efficacy of the procedure and potential complications. Furthermore, acquiring a grasp of the different modalities of AF ablation (including percutaneous endocardial techniques and surgical ablation approaches) will help to facilitate effective and appropriate referrals.

Outcomes of Micra leadless pacemaker implantation with uninterrupted anticoagulation

BACKGROUND

Implantation of the MICRA Leadless pacemaker requires the use of a 27 French introducer, blunt delivery system and device fixation to the myocardium via nitinol tines. While prior studies have proven its safety, it is unclear whether performing this procedure with uninterrupted anticoagulation exposes patients to increased risks. We sought to investigate the feasibility and safety of continuing therapeutic anticoagulation during the periprocedural period.

METHODS

We evaluated all patients undergoing MICRA placement at our institution between April 2014 and August 2018 with complete follow-up data (n = 170). Patients were stratified into two groups: those on active anticoagulation (OAC, n = 26), defined as having an International normalized ratio >2.0 or having continued a direct oral anticoagulant, and those not anticoagulated (Off-OAC, n = 144). We evaluated for a composite outcome of all major complications, including access site complications and pericardial effusion.

RESULTS

OAC and Off-OAC groups had similar mean age (74 ± 13 vs 75 ± 13 years; P = .914). The OAC group had a nonsignificantly lower prevalence of end-stage renal disease (8% vs 17%; P = .375) and aspirin use (27% vs 47%; P = .131). Those in the OAC group were more likely to be on warfarin than those in the Off-OAC group (81% vs 30%; P < .001). The rate of the composite endpoint was similar between the OAC and Off-OAC groups (3.8 % vs 1.4%, respectively; P = .761). Length of stay was similar between groups (1.3 ± 2.6 vs 2.3 ± 3.4 days; P = 0.108).

CONCLUSION

Continuation of therapeutic anticoagulation during MICRA implantation appears to be feasible, safe and associated with shorter hospitalization among appropriately selected individuals.

Report of periprocedural oral anticoagulants in catheter ablation for atrial fibrillation: The Japanese Catheter Ablation Registry of Atrial Fibrillation (J-CARAF)

BACKGROUND

To obtain a perspective of the current status of catheter ablation for the cure of atrial fibrillation, the Japanese Heart Rhythm Society conducted a nationwide survey: the Japanese Catheter Ablation Registry of Atrial Fibrillation. In this report, we aimed to evaluate the periprocedural use of direct oral anticoagulants with respect to thromboembolic or bleeding complications.

METHODS

Using an online questionnaire, the Japanese Heart Rhythm Society requested electrophysiology centers in Japan to register the relevant data of patients who underwent atrial fibrillation ablation over selected five-months from 2011 to 2014. We compared the clinical profiles and the ablation data, including the incidence of pericardial effusion, major bleeding, and ischemic stroke among patients with periprocedural use of warfarin or a direct oral anticoagulant.

RESULTS

A total of 204 institutions reported data on 6200 atrial fibrillation ablation sessions. We analyzed data obtained from 4698 subjects (Age 63.2±10.6 yr; 73.9% male, 26.1% female) who were administered warfarin or a direct oral anticoagulant, at least up to the day before atrial fibrillation ablation. Warfarin was administered to 54.7% of patients. Dabigatran, rivaroxaban, and apixaban were used in 21.9%, 12.9%, and 10.6% of patients, respectively. Clinical profiles of apixaban-treated patients were similar to those of warfarin-treated patients; they were different from the clinical profiles of patients treated with dabigatran or rivaroxaban. There were 104 complications in 103 subjects (2.2%). Complications were more frequent in older patients (65.3±8.6 yr vs. 63.1±10.7 yr; P=0.012), patients on chronic hemodialysis (4.9% vs. 1.1%; P=0.001), or those treated with warfarin (66.0% vs. 54.4%; P=0.019). Multiple logistic regression analysis revealed that age (OR, 1.02; 95% CI: 1.00-1.04; P=0.035), chronic hemodialysis (OR, 4.40; CI: 1.68-11.50; P=0.003), and assistance by 3-D mapping system (OR, 0.30; CI: 0.16-0.57; P<0.001) were significantly related to the incidence of complications, while periprocedural direct oral anticoagulant was not a predictive factor for complication.

CONCLUSIONS

Compared with uninterrupted warfarin, the choice of a direct oral anticoagulant as a periprocedural oral anticoagulant did not significantly change the incidence of serious complications.

Incidence and predictors of pericardial effusion as an early complication of catheter ablation for atrial fibrillation: The Japanese Catheter Ablation Registry of Atrial Fibrillation (J-CARAF)

BACKGROUND

Pericardial effusion (PE) is one of the most frequent complications from catheter ablation of atrial fibrillation (AF). We assessed the prevalence and predictive factors of PE that require invasive treatment as an early complication of AF ablation.

METHODS

The Japanese Heart Rhythm Society requested electrophysiology centers to register the relevant data of patients who underwent AF ablation during 6 months from 2011 to 2015. We compared the clinical profiles and the procedures of AF ablation between patients who had ablation-related PE and those who did not.

RESULTS

Two-hundred-and-eight institutions reported the data of 8319 AF ablation sessions (age 63.4±10.7 years). A total of 414 complications occurred in 401 patients (4.8%). The incidence of invasively treated critical PE was 1.0% (n=85) of total procedures, while conservatively treated noncritical PE appeared in 95 subjects. When clinical and procedural variables were compared between patients who suffered critical PE and 8140 PE-free patients, deep sedation (p=0.030), impaired left ventricular function (p=0.031), and periprocedural warfarin (p=0.023) significantly increased the incidence of critical PE in univariate analysis. Use of 3-D imaging system (p<0.001) and a periprocedural direct oral anticoagulant (DOAC, p=0.002) were related with lower incidence of critical PE. Among these factors, multivariate logistic regression analysis showed that 3-D imaging system (odds ratio 0.23 [95% CI: 0.14-0.39], p<0.001) and a periprocedural DOAC (odds ratio 0.49 [95% CI: 0.27-0.90], p=0.020) are independent predictors of the lower incidence of PE.

CONCLUSIONS

Critical PE occurred in 1% of AF ablation procedures in Japan. Our results suggest that 3-D imaging system use independently reduces the frequency of PE. DOACs in the setting of catheter ablation of AF seemed to be non-inferior to warfarin in terms of safety and effectiveness.

The State of the Art: Atrial Fibrillation Epidemiology, Prevention, and Treatment

As the most common sustained arrhythmia in adults, atrial fibrillation (AF) is an established and growing epidemic. To provide optimal patient care, it is important for clinicians to be aware of AF's epidemiological trends, methods of risk reduction, and the various available treatment modalities. Our understanding of AF's pathophysiology has advanced, and with this new understanding has come advancements in prevention strategies as well as pharmacological and nonpharmacological treatment options. Following PubMed and MEDLINE searches for AF risk factors, epidemiology, and therapies, we reviewed relevant articles (and bibliographies of those articles) published from 2000 to 2016. This "state-of-the-art" review provides a comprehensive update on the understanding of AF in the world today, contemporary therapeutic options, and directions of ongoing and future study.

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.

Uninterrupted rivaroxaban vs. uninterrupted vitamin K antagonists for catheter ablation in non-valvular atrial fibrillation

Aims

VENTURE-AF is the first prospective randomized trial of uninterrupted rivaroxaban and vitamin K antagonists (VKAs) in patients with non-valvular atrial fibrillation (NVAF) undergoing catheter ablation (CA).

Methods and results

Trial size was administratively set at 250, the protocol-specified target. Events were independently and blindly adjudicated. We randomly assigned 248 NVAF patients to uninterrupted rivaroxaban (20 mg once-daily) or to an uninterrupted VKA prior to CA and for 4 weeks afterwards. The primary endpoint was major bleeding events after CA. Secondary endpoints included thromboembolic events (composite of stroke, systemic embolism, myocardial infarction, and vascular death) and other bleeding or procedure-attributable events. Patients were 59.5 ± 10 years of age, 71% male, 74% paroxysmal AF, and had a CHA2DS2-VASc score of 1.6. The average total heparin dose used to manage activated clotting time (ACT) was slightly higher (13 871 vs. 10 964 units; P < 0.001) and the mean ACT level attained slightly lower (302 vs. 332 s; P < 0.001) in rivaroxaban and VKA arms, respectively. The incidence of major bleeding was low (0.4%; 1 major bleeding event). Similarly, thromboembolic events were low (0.8%; 1 ischemic stroke and 1 vascular death). All events occurred in the VKA arm and all after CA. The number of any adjudicated events (26 vs. 25), any bleeding events (21 vs. 18), and any other procedure-attributable events (5 vs. 5) were similar.

Conclusion

In patients undergoing CA for AF, the use of uninterrupted oral rivaroxaban was feasible and event rates were similar to those for uninterrupted VKA therapy.

Name of the Trial Registry

Clinicaltrials.gov trial registration number is NCT01729871.

Periprocedural Management of New Oral Anticoagulants in Atrial Fibrillation Ablation

BACKGROUND

Patients who undergo catheter ablation for atrial fibrillation (AF) are at increased risk of developing thromboembolic and bleeding complications periprocedurally. Many patients are now on newer oral anticoagulants (NOACs), but data regarding their safety and efficacy during AF ablation are limited.

METHODS AND RESULTS

This article reviews the literature in PubMed from 1998 to 2014 and includes clinical trials and meta-analysis that analyzed the safety and efficacy of NOACs during AF catheter ablation. Dabigatran seems to be as effective and safe as warfarin, although most data are from single-center studies, with small samples and very low overall bleeding and thromboembolic complications. Periprocedural anticoagulation protocols also vary greatly between studies. Some recent meta-analysis has shown that warfarin could still be a safer and more effective alternative. There are fewer studies with rivaroxaban in AF ablation, and there have been no meta-analysis yet comparing rivaroxaban to warfarin or dabigatran. There seems to be no significant differences in safety or efficacy of rivaroxaban compared to warfarin. Interestingly, there are no available data for apixaban in AF ablation yet.

DISCUSSION

There are no consensus guidelines regarding the use of NOACs during AF ablation. Dabigatran and rivaroxaban seem as safe and effective as warfarin, although larger studies with standardized protocols are needed, as available studies may be underpowered to detect small differences in bleeding and thromboembolic rates.

Influence of the concomitant use of heparin on the effects of warfarin during catheter ablation for atrial fibrillation

Warfarin is widely used to perform catheter ablation for atrial fibrillation (AF). Heparin is usually administered during this procedure to prevent thromboembolic events, while protamine is used to reduce the incidence of bleeding complications. The purpose of this study was to investigate the influence of heparin and protamine administration on the effects of warfarin and its safety. The subjects included 226 AF patients (206 males, 54.9 ± 9.1 years, paroxysmal/persistent AF: 118/108) undergoing AF ablation with the discontinuation of warfarin administration over 2 days. Heparin was administered to achieve an activated clotting time (ACT) above 300 s during the procedure. Several parameters of the coagulation status, including the prothrombin time international normalized ratio (PT-INR) and ACT values, measured immediately before and after protamine infusion were compared. The mean value of PT-INR prior to ablation was 1.9 ± 0.6. At the end of the procedure, the mean ACT and PT-INR values were 348.0 ± 52.9 and 2.9 ± 0.7, respectively. Following the infusion of 30 mg of protamine, both the ACT and PT-INR values significantly decreased, to 159.6 ± 31.0 (p < 0.0001) and 1.6 ± 0.3 (p < 0.0001), respectively. No cases of symptomatic cerebral infarction were observed, although femoral hematomas developed in 17 (7.5 %) of the patients without further consequence. The concomitant use of heparin augments the effect of warfarin. Meanwhile, protamine administration immediately reverses both the ACT and PT-INR, indicating the applicability of protamine for AF ablation in patients under the mixed administration of heparin and warfarin.

Safety of Continuous Periprocedural Rivaroxaban for Patients Undergoing Left Atrial Catheter Ablation Procedures

Background—

This study aimed to evaluate the safety of continuous periprocedural rivaroxaban administration during left atrial radiofrequency ablation (RFA) in comparison with uninterrupted oral vitamin K antagonist administration. Data about the use of rivaroxaban in the setting of left atrial RFA procedures are lacking.

Methods and Results—

The study cohort included 544 patients (mean age, 63±10 years) who underwent left atrial RFA procedures between February 2012 and May 2013. All patients (n=272) receiving uninterrupted periprocedural rivaroxaban 15 or 20 mg/d before the procedure (rivaroxaban) were matched by age, sex, and type of rhythm disorder with an equal number of patients managed with uninterrupted vitamin K antagonist phenprocoumon (international normalized ratio, 2–3). During RFA, heparin was given intravenously to maintain an activated clotting time at 270 to 300 s. The safety end point was a composite of bleeding, thromboembolic events, and death. There were no thromboembolic complications and no deaths in either group. The prevalence of major bleeding complications was similar in both groups (1 tamponade in RivG and 1 groin hematoma requiring transfusion in phenprocoumon). Minor bleeding complications occurred equally in both groups (20 of 272; 7% in the rivaroxaban versus 33 of 272, 12% in the phenprocoumon; P =0.08). In multivariable analyses, female sex was associated with a greater risk of complications (odds ratio, 1.96; 95% confidence interval, 1.10–3.49).

Conclusions—

In patients undergoing left atrial RFA, continuous periprocedural rivaroxaban use seems to be as safe as uninterrupted periprocedural phenprocoumon administration.

Nationwide survey of catheter ablation for atrial fibrillation: The Japanese catheter ablation registry of atrial fibrillation (J-CARAF)-A report on periprocedural oral anticoagulants

BACKGROUND

Catheter ablation has become an established therapy for the treatment of atrial fibrillation (AF). To obtain a perspective on the current status of this therapy in Japan, the Japanese Heart Rhythm Society (JHRS) conducted a nationwide survey, the Japanese Catheter Ablation Registry of Atrial Fibrillation (J-CARAF). In this study, we focused on whether periprocedural use of novel oral anticoagulants (NOACs) was related with excessive thromboembolic or bleeding complications.

METHODS

Using an online questionnaire, JHRS requested electrophysiology centers in Japan to register the data of patients who underwent AF ablations in September 2011, March 2012, and September 2012. We compared the clinical profiles and ablation data, including the incidence of complications among patients in whom warfarin, a NOAC or neither was used as a periprocedural anticoagulant.

RESULTS

A total of 179 centers submitted data relating to 3373 patients (62.2±10.6 years). Paroxysmal atrial fibrillation (PAF) was observed in 64.4% of patients. Warfarin, as a periprocedural oral anticoagulant, was used by 53.6% (1808/3373) of patients. A NOAC was given to 541 subjects (dabigatran: 504 [16.1%], rivaroxaban: 37 [1.1%]). In the remaining 1024 patients (30.4%), no periprocedural oral anticoagulants (OACs) were used. The proportion of PAF in warfarin-treated patients (61.1%) was significantly lower than that in NOAC-treated patients (70.1%, p<0.01) or in patients not treated with an OAC (67.4%, p<0.01). Patients treated with uninterrupted warfarin therapy were associated with significantly higher CHA2DS2-VASc scores. A total of 158 complications occurred in 151 subjects (4.5%). The incidence of complications in NOAC-treated patients (14/541 [2.6%]) was lower than that in patients receiving uninterrupted warfarin therapy (4.8%, p<0.05). The incidence of pericardial effusion in NOAC-treated patients (0.7%) was lower than in warfarin-treated patients (2.6%, p<0.05). The difference in the periprocedural anticoagulant strategy was not related to the frequency of other bleeding events. Cerebral infarction occurred in one patient from each patient group.

CONCLUSIONS

Our results suggest that NOACs are safe for use as substitutes for warfarin without causing excessive increases in the rates of thromboembolic or bleeding complications.

Dabigatran versus warfarin anticoagulation before and after catheter ablation for the treatment of atrial fibrillation

BACKGROUND

Systemic thromboembolism and bleeding remain the two most common and serious complications of catheter ablation of atrial fibrillation. A variety of periprocedure anticoagulation strategies have been proposed to mitigate these risks. Although operators are now routinely administering dabigatran for anticoagulation in this setting, its relative safety and effectiveness compared to warfarin are unknown.

METHODS AND RESULTS

A total of 202 patients received dabigatran as part of their periprocedural anticoagulation regimen at the time of initial or redo catheter ablation for symptomatic atrial fibrillation. A comparison group of 202 patients treated with warfarin was randomly selected from patients undergoing atrial fibrillation (AF) ablation during the same time period. AF types were paroxysmal in 223 patients, persistent in 158 patients, and longstanding persistent in 13 patients. Mean age was 60.0 ± 10.5 years, 55 % had a history of hypertension, and mean CHADS-VASc score was 1.7 ± 1.3. "Continuous" warfarin or dabigatran was administered in 80 and 32 % of patients, respectively. Time to first dose of dabigatran post-procedure was 12.2 ± 10.3 h. Two dabigatran and no warfarin-treated patients had systemic thromboembolism (p = NS); five dabigatran and three warfarin-treated patients had bleeding complications (p = NS, combined endpoint p = 0.116). One dabigatran patient had severe pericardial bleeding (3 L blood loss).

CONCLUSIONS

In a retrospective pilot trial comparing the risks of systemic thromboembolism or bleeding complications in patients treated with warfarin or dabigatran anticoagulation, the outcomes were similar. A prospective trial is warranted.

Continuous warfarin versus periprocedural dabigatran to reduce stroke and systemic embolism in patients undergoing catheter ablation for atrial fibrillation or left atrial flutter

PURPOSE

Left atrial catheter ablation for patients with atrial fibrillation (AF) requires periprocedural anticoagulation to minimize thromboembolic complications. High rates of major bleeding complications using dabigatran etexilate for periprocedural anticoagulation have been reported, raising concerns regarding its safety during left atrial catheter ablation. We sought to evaluate the safety and efficacy of a dabigatran use strategy versus warfarin, at a single high-volume AF ablation center.

METHODS

We performed a retrospective analysis on consecutive patients undergoing left atrial ablation at Vanderbilt Medical Center from January 2011 through August 2012 with a minimum follow-up of 3 months. Patient cohorts were divided into two groups, those utilizing dabigatran etexilate pre- and post-ablation and those undergoing ablation on dose-adjusted warfarin, with or without low-molecular-weight heparin bridging. Dabigatran was held 24-30 h pre-procedure and restarted 4-6 h after hemostasis was achieved. We evaluated all thromboembolic and bleeding complications at 3 months post-ablation.

RESULTS

A total of 254 patients underwent left atrial catheter ablation for atrial fibrillation or left atrial flutter. Periprocedural anticoagulation utilized dabigatran in 122 patients and warfarin in 135 patients. Three late thromboembolic complications occurred in the dabigatran group (2.5 %), compared with one (0.7 %) in the warfarin group (p = 0.28). The dabigatran group had similar minor bleeding (2.5 vs. 7.4 %, p = 0.07), major bleeding (1.6 vs. 0.7 %, p = 0.51), and composite of bleeding and thromboembolic complications (6.6 vs. 8.9 %, p = 0.49) when compared to warfarin. There were no acute thromboembolic complications in either group (<24 h post-ablation).

CONCLUSIONS

In patients undergoing left atrial catheter ablation for AF or left atrial flutter, use of periprocedural dabigatran etexilate provides a safe and effective anticoagulation strategy compared to warfarin. A prospective randomized study is warranted.

Clinical considerations of anticoagulation therapy for patients with atrial fibrillation

Atrial fibrillation (AF) increases the risk of stroke. New anticoagulation agents have recently provided alternative and promising approaches. This paper reviews the current state of anticoagulation therapy in AF patients, focusing on various clinical scenarios and on comparisons, where possible, between western and eastern populations.