Clinical comparative study regarding interrupted and uninterrupted dabigatran therapy during perioperative periods of cryoballoon ablation for paroxysmal atrial fibrillation

Exploring the Perioperative Use of DOACs, off the Beaten Track

A notable increase in direct oral anticoagulant (DOAC) use has been observed in the last decade. This trend has surpassed the prescription of vitamin K antagonists (VKAs) due to the absence of the need for regular laboratory monitoring and the more favorable characteristics in terms of efficacy and safety. However, it is very common that patients on DOACs need an interventional or surgical procedure, requiring a careful evaluation and a challenging approach. Therefore, perioperative anticoagulation management of patients on DOACs represents a growing concern for clinicians. Indeed, while several surgical interventions require temporary discontinuation of DOACs, other procedures that involve a lower risk of bleeding can be conducted, maintaining a minimal or uninterrupted DOAC strategy. Therefore, a comprehensive evaluation of patient characteristics, including age, susceptibility to stroke, previous bleeding complications, concurrent medications, renal and hepatic function, and other factors, in addition to surgical considerations, is mandatory to establish the optimal discontinuation and resumption timing of DOACs. A multidisciplinary approach is required for managing perioperative anticoagulation in order to establish how to face these circumstances. This narrative review aims to provide physicians with a practical guide for DOAC perioperative management, addressing the most controversial issues.

Safety and efficacy of direct oral anticoagulation in patients with and without radiofrequency ablation of non-valvular atrial fibrillation: a multicenter retrospective cohort study

BACKGROUND

Based on the few available studies on the prognostic benefit of using direct oral anticoagulants (DOACs) after atrial fibrillation (AF) ablation. Therefore, this study aimed to evaluate the prognostic differences between patients who underwent radiofrequency ablation (RFA) and those without RFA taking DOACs.

METHODS

This is a multicenter retrospective cohort study enrolling 6137 patients with non-valvular AF (NVAF) at 15 hospitals in China. Patient information was collected through a mean follow-up of 10 months and medical record queries. Clinical outcomes included major bleeding, total bleeding, thrombosis, all-cause death, and a composite endpoint of bleeding, thrombosis, and all-cause death.

RESULTS

After adjusting for confounders and propensity score matching (PSM), patients with RFA of NVAF had a significantly lower risk of major bleeding [OR 0.278 (95% CI, 0.150-0.515), P<0.001], thrombosis [OR 0.535 (95% CI, 0.316-0.908), P=0.020] and the composite endpoint [ OR 0.835 (95% CI, 0.710-0.982), P=0.029]. In the RFA PSM cohort, dabigatran was associated with reduced all-cause death in patients with RFA of NVAF [OR 0.420 (95% CI, 0.212-0.831), P=0.010]. In the no RFA PSM cohort, rivaroxaban was associated with a reduction in major bleeding [OR 0.521 (95% CI, 0.403-0.673), P<0.001], total bleeding [OR 0.114 (95% CI, 0.049-0.266), P<0.001], and the composite endpoint [OR 0.659 ( 95% CI, 0.535-0.811), P<0.001].

CONCLUSION

Among patients with NVAF treated with DOACs, RFA was a negative correlate of major bleeding, thrombosis, and composite endpoints but was not associated with total bleeding or all-cause mortality.

Effects of uninterrupted dabigatran on the intensity of anticoagulation during atrial fibrillation ablation

BACKGROUND

Uninterrupted dabigatran during atrial fibrillation (AF) ablation is now established as the standard therapy. However, there are few reports on the effects of uninterrupted dabigatran on the intensity of anticoagulation during AF ablation.

METHODS

We retrospectively analyzed 247 consecutive patients who underwent AF ablation in our hospital from January 2017 to December 2018. Patients who took warfarin or uninterrupted direct oral anticoagulants (DOACs) except for dabigatran were excluded. 89 patients underwent ablation with uninterrupted dabigatran (uninterrupted group, male 71, mean age 59.6 ± 14.0) and 124 with interrupted DOACs (interrupted group, male 105, mean age 56.9 ± 12.9) during AF ablation. The initial ACT level, proportion of ACT levels of more than 300 s, and total amount of heparin were compared. Furthermore, the incidence of procedure complications was also evaluated.

RESULTS

The initial ACT levels were significantly higher in the uninterrupted group, and the total number of ACTs of more than 300 s was significantly higher in the uninterrupted group (uninterrupted vs. interrupted; initial ACT level, 315.6 ± 59.8 vs. 264.5 ± 48.6, p < .001; total number of ACTs ≧300, n [%], 304/ 484 [62.8 %] vs. 372/745 [49.9%], p < .001). The total amount of heparin during procedure was significantly lower in the uninterrupted group (uninterrupted group vs. interrupted group; 12966 ± 4773 vs. 16371 ± 5212, p < .001). There was no significant difference in the incidence of complications between the two groups.

CONCLUSIONS

In the catheter ablation of AF, uninterrupted dabigatran would be useful to obtain a stable anticoagulation status during the entire procedure.

Perioperative management of antithrombotic therapy: a case-based narrative review

The periprocedural management of patients who are receiving vitamin K antagonists, direct oral anticoagulants and antiplatelet therapy is a common and challenging clinical scenario as the decision to interrupt or continue these medications is anchored on patient and procedure-related risks for bleeding and thrombosis. Adding to the complexity of clinical management is the fact that anticoagulants have varied pharmacokinetic and pharmacodynamic properties and indications for clinical use. In many minimal-bleed-risk procedures, anticoagulants can be safely continued, without interruption, whereas in cases where anticoagulants cannot be safely continued, the timing of interruption and resumption, as well as the need for heparin bridging requires consideration. Perioperative antithrombotic management scenarios occur most often in patients with atrial fibrillation, mechanical heart valves, coronary stents, and cerebrovascular disease as such patients are likely to be prescribed anticoagulant and/or antiplatelet therapy. The objective of this case-based narrative review is to provide a practical evidence-based approach to the perioperative management of patients on anticoagulation and antiplatelet therapy. Four clinical scenarios will be provided: (1) managing patients in whom anticoagulants can be continued; (2) perioperative management of direct oral anticoagulants; (3) management of patients on dual antiplatelet therapy; and (4) anticoagulant management for emergency or urgent surgery.

Interrupted versus uninterrupted anticoagulation therapy for catheter ablation in adults with arrhythmias

BACKGROUND

The management of anticoagulation therapy around the time of catheter ablation (CA) procedure for adults with arrhythmia is critical and yet is variable in clinical practice. The ideal approach for safe and effective perioperative management should balance the risk of bleeding during uninterrupted anticoagulation while minimising the risk of thromboembolic events with interrupted therapy.

OBJECTIVES

To compare the efficacy and harms of interrupted versus uninterrupted anticoagulation therapy for catheter ablation (CA) in adults with arrhythmias.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and SCI-Expanded on the Web of Science for randomised controlled trials on 5 January 2021. We also searched three registers on 29 May 2021 to identify ongoing or unpublished trials. We performed backward and forward searches on reference lists of included trials and other systematic reviews and contacted experts in the field. We applied no restrictions on language or publication status.

SELECTION CRITERIA

We included randomised controlled trials comparing uninterrupted anticoagulation with any modality of interruption with or without heparin bridging for CA in adults aged 18 years or older with arrhythmia.

DATA COLLECTION AND ANALYSIS

Two review authors conducted independent screening, data extraction, and assessment of risk of bias. A third review author resolved disagreements. We extracted data on study population, interruption strategy, ablation procedure, thromboembolic events (stroke or systemic embolism), major and minor bleeding, asymptomatic thromboembolic events, cardiovascular and all-cause mortality, quality of life (QoL), length of hospital stay, cost, and source of funding. We used GRADE to assess the certainty of the evidence.  MAIN RESULTS: We identified 12 studies (4714 participants) that compared uninterrupted periprocedural anticoagulation with interrupted anticoagulation. Studies performed an interruption strategy by either a complete interruption (one study) or by a minimal interruption (11 studies), of which a single-dose skipped strategy was used (nine studies) or two-dose skipped strategy (two studies), with or without heparin bridging. Studies included participants with a mean age of 65 years or greater, with only two studies conducted in relatively younger individuals (mean age less than 60 years). Paroxysmal atrial fibrillation (AF) was the primary type of AF in all studies, and seven studies included other types of AF (persistent and long-standing persistent). Most participants had CHADS2 or CHADS2-VASc demonstrating a low-moderate risk of stroke, with almost all participants having normal or mildly reduced renal function. Ablation source using radiofrequency energy was the most common (seven studies). Ten studies (2835 participants) were conducted in East Asian countries (Japan, China, and South Korea), while the remaining two studies were conducted in the USA. Eight studies were conducted in a single centre. Postablation follow-up was variable among studies at less than 30 days (three studies), 30 days (six studies), and more than 30 days postablation (three studies). Overall, the meta-analysis showed high uncertainty of the effect between the interrupted strategy compared to uninterrupted strategy on the primary outcomes of thromboembolic events (risk ratio (RR) 1.76, 95% confidence interval (CI) 0.33 to 9.46; I2 = 59%; 6 studies, 3468 participants; very low-certainty evidence). However, subgroup analysis showed that uninterrupted vitamin A antagonist (VKA) is associated with a lower risk of thromboembolic events without increasing the risk of bleeding. There is also uncertainty on the outcome of major bleeding events (RR 1.10, 95% CI 0.59 to 2.05; I2 = 6%; 10 studies, 4584 participants; low-certainty evidence). The uncertainty was also evident for the secondary outcomes of minor bleeding (RR 1.01, 95% CI 0.46 to 2.22; I2 = 87%; 9 studies, 3843 participants; very low-certainty evidence), all-cause mortality (RR 0.34, 95% CI 0.01 to 8.21; 442 participants; low-certainty evidence) and asymptomatic thromboembolic events (RR 1.45, 95% CI 0.85 to 2.47; I2 = 56%; 6 studies, 1268 participants; very low-certainty evidence). There was a lower risk of the composite endpoint of thromboembolic events (stroke, systemic embolism, major bleeding, and all-cause mortality) in the interrupted compared to uninterrupted arm (RR 0.23, 95% CI 0.07 to 0.81; 1 study, 442 participants; low-certainty evidence). In general, the low event rates, different comparator anticoagulants, and use of different ablation procedures may be the cause of imprecision and heterogeneity observed.

AUTHORS' CONCLUSIONS

This meta-analysis showed that the evidence is uncertain to inform the decision to either interrupt or continue anticoagulation therapy around CA procedure in adults with arrhythmia on outcomes of thromboembolic events, major and minor bleeding, all-cause mortality, asymptomatic thromboembolic events, and a composite endpoint of thromboembolic events (stroke, systemic embolism, major bleeding, and all-cause mortality).  Most studies in the review adopted a minimal interruption strategy which has the advantage of reducing the risk of bleeding while maintaining a lower level of anticoagulation to prevent periprocedural thromboembolism, hence low event rates on the primary outcomes of thromboembolism and bleeding. The one study that adopted a complete interruption of VKA showed that uninterrupted VKA reduces the risk of thromboembolism without increasing the risk of bleeding. Hence, future trials with larger samples, tailored to a more generalisable population and using homogeneous periprocedural anticoagulant therapy and ablation source are required to address the safety and efficacy of the optimal management of anticoagulant therapy prior to ablation.

Meta-analysis of controlled studies on minimally interrupted vs. continuous use of non-vitamin K antagonist oral anticoagulants in catheter ablation for atrial fibrillation

Aims

At present, there are no guideline recommendations for minimally interrupted use of non-vitamin K antagonist oral anticoagulants (mi-NOAC) during catheter ablation (CA) for atrial fibrillation (AF). Current evidence is predominantly based on observational studies, with continuous use of vitamin K antagonist in the control arm. This quantitative summary reflects the first high-level evidence on contemporary regimens, with continuous NOAC use (c-NOAC) as the current gold standard.

Methods and results

Meta-analysis (Pubmed, Embase, and Web of Science) on prospective, controlled studies comparing contemporary mi-NOAC (without bridging) with c-NOAC. Net adverse clinical events (major bleeding, thrombo-embolic events) were the primary outcome. In addition, we analysed total bleeding, minor bleeding, and silent cerebral embolism.

Eight studies (six randomized, two observational) with 2168 patients were summarized. The primary endpoint occurred in 1.0% (18/1835): 1.1% (11/1005) vs. 0.8% (7/830) for the mi-NOAC and c-NOAC groups, respectively; odds ratio (OR) 1.20 [95% confidence interval (CI) 0.49–2.92, P = 0.64]. The OR for total bleeding on mi-NOAC was 1.26 (95% CI 0.97–1.63, P = 0.07). ORs for minor bleeding and silent cerebral embolism were 1.17 (95% CI 0.80–1.70, P = 0.34) and 2.62 (95% CI 0.54–12.61, P = 0.12), respectively.

Conclusion

This synopsis provides a quantitative synthesis of high-level evidence on a contemporary strategy of mi-NOAC in CA for AF, and overall clinical outcomes were not different from continuous NOAC use. Despite preprocedural interruption, there was no sign of lower bleeding rates. Additional higher volume datasets are warranted for more precise treatment effect estimations of this everyday alternative anticoagulation strategy in AF ablation.

Clinical Efficacy and Safety Comparison of Rivaroxaban and Dabigatran for Nonvalvular Atrial Fibrillation Patients Undergoing Percutaneous Left Atrial Appendage Closure Operation

Objective: Due to the clinical complexity of warfarin, novel oral anticoagulation (NOAC) has been a feasible and safe alternative anticoagulant approach during left atrial appendage closure (LAAC). This study was designed to compare the efficacy and safety of rivaroxaban and dabigatran for nonvalvular atrial fibrillation patients undergoing percutaneous LAAC.

Methods: One single and prospective cohort study was performed among patients who received anticoagulation with dabigatran or rivaroxaban. All patients were medicated with a 3-month course of NOAC to facilitate device endothelialization, followed by dual antiplatelet therapy until 6 months, then lifelong aspirin after discharge. Repeated transesophageal echocardiography was scheduled to evaluate thrombosis formation on occluders and thrombus dissolution ability.

Results: A total of 262 consecutive patients were initially enrolled. A final number of 250 patients were analyzed; two patients were excluded due to procedure failure and 10 patients had a loss of follow-up; 97 were from the dabigatran group and 153 from the rivaroxaban group. Three patients (1.9%) in the rivaroxaban group and eight (8.2%) in the dabigatran group were experiencing device-related thrombosis (DRT) events during follow-ups. Cumulative Kaplan–Meier estimates showed that the incidence of DRT was lower under rivaroxaban medication during the 6-month follow-ups (p = 0.038*, OR = 3.843, 95%CI: 0.991–14.836). The transesophageal echocardiography (TEE) results showed that the average length and width of DRT in the rivaroxaban group was significantly lower compared with that in the dabigatran group (2.16 vs. 1.60 mm, p = 0.017*, and 1.71 vs. 1.30 mm, p = 0.003*, respectively). The thrombosis dissolved after the switch from dabigatran or rivaroxaban to warfarin within the target range, represented by the average length and width of thrombus with the cooperation of secondary TEE for the dabigatran and rivaroxaban groups (0.64 vs. 0.40 mm, p = 0.206, and 0.43 vs. 0.27 mm, p = 0.082, respectively). No significant difference was found between the two groups with respect to the levels of coagulation parameters, cardiac function, and bleeding events.

Conclusion: Compared to dabigatran, post-procedural rivaroxaban anticoagulation might be advantageous in preventing DRT complications expected after LAAC, without increasing the risk of hemorrhage.

Uninterrupted versus interrupted direct oral anticoagulation for catheter ablation of atrial fibrillation: A systematic review and meta-analysis

INTRODUCTION

To evaluate the safety of uninterrupted versus interrupted direct oral anticoagulation (DOAC) for patients undergoing catheter ablation (CA) of atrial fibrillation (AF).

METHODS

We conducted a systematic search of MEDLINE and EMBASE for randomized controlled trials (RCT) and observational studies comparing uninterrupted versus interrupted DOAC for patients undergoing CA of AF. Primary outcome was major bleeding. Secondary outcomes included minor bleeding, stroke or transient ischemic attack (TIA) or thromboembolism (TE), silent cerebral ischemic events, and cardiac tamponade. Meta-analysis was stratified by study design. Risk ratios (RR) with 95% confidence intervals were calculated using random effects model and Mantel-Haenszel method was used to pool RR.

RESULTS

A total of 13 studies (7 randomized, 6 observational) comprising 3595 patients were included. The RCT restricted analysis did not show any difference in terms of major bleeding (risk ratio [RR] = 0.79; [0.35-1.79]), minor bleeding (RR = 0.99 [0.68-1.43]), stroke or TIA or TE (RR = 0.80 [0.19-3.32]), silent cerebral ischemic events (RR = 0.64 [0.32-1.28]), and cardiac tamponade (RR = 0.61 [0.20-1.92]). Observational study restricted analysis showed a protective effect of uninterrupted DOAC on silent cerebral ischemic events (RR = 0.45 [0.31-0.67]) and no difference in other outcomes.

CONCLUSIONS

There is no difference in bleeding and thromboembolic outcomes with uninterrupted versus interrupted DOAC for CA of AF and observational data suggests that uninterrupted DOACs are protective against silent cerebral ischemic lesions.

Outcomes of uninterrupted vs interrupted Periprocedural direct oral Anticoagulants in atrial Fibrillation ablation: A meta-analysis

BACKGROUND

Studies indicate that uninterrupted anticoagulation (UA) is superior to interrupted anticoagulation (IA) in the periprocedural period during catheter ablation of atrial fibrillation. Still IA is followed in many centers considering the bleeding risk. This meta-analysis compares interrupted and uninterrupted direct oral anticoagulation during catheter ablation of atrial fibrillation.

METHODS

A systematic search into PubMed, EMBASE, and the Cochrane databases was performed and five studies were selected that directly compared IA vs UA before ablation and reported procedural outcomes, embolic, and bleeding events. The primary outcome of the study was major adverse cerebro-cardiovascular events.

RESULTS

The meta-analysis included 840 patients with UA and 938 patients with IA. Median follow-up was 30 days. Activated clotting time (ACT) before first heparin bolus was significantly longer with UA (P = .006), whereas mean ACT was similar between the two groups (P = .19). Total heparin dose needed was significantly higher with IA (mean, ‒1.61; 95% CI, ‒2.67 to ‒0.55; P = .003). Mean procedure time did not vary between groups (P = .81). Overall complication rates were low, with similar major adverse cerebro-cardiovascular event (P = .40) and total bleeding (P = .55) rates between groups. Silent cerebral events (SCEs) were significantly more frequent with IA (log odds ratio, ‒0.90; 95% CI, ‒1.59 to ‒0.22; P < .01; I 2, 33%). Rates of major bleeding, minor bleeding, pericardial effusion, cardiac tamponade, and puncture complications were similar between groups.

CONCLUSIONS

UA during atrial fibrillation ablation has similar bleeding event rates, procedural times, and mean ACTs as IA, with fewer SCEs.

Optimal interruption time of dabigatran oral administration to ablation (O-A time) in patients with atrial fibrillation: Integrated analysis of 2 randomized controlled clinical trials

BACKGROUND

RE-CIRCUIT (NCT02348723) and ABRIDGE-J (UMIN000013129) are recently published randomized clinical trials showing that anticoagulation therapy with dabigatran during the periprocedural period of catheter ablation (CA) for atrial fibrillation (AF) was associated with fewer complications. However, the dabigatran administration protocols were different (uninterrupted in RE-CIRCUIT and minimally interrupted in ABRIDGE-J). The aim of this present study was to clarify the optimal interruption time of dabigatran Oral administration to Ablation (O-A time).

METHODS

We conducted an integrated analysis of the 2 prospective trials. The endpoint of the study was the incidence of major bleeding events during and up to 8 weeks after CA across participants with different O-A times.

RESULTS

The 535 patients in the dabigatran groups of the 2 trials were divided into 3 groups based on their O-A times (<8 h, n = 258; 8-24 h, n = 191; >24 h, n = 86). Major bleeding events occurred in 5 patients (1.9%) in the <8 h group, and 3 (3.5%) in the >24 h group; however, no major bleeding events occurred in the 8-24 h group (3 group-comparison, p = 0.026). No thromboembolic complication was observed in any of the 3 O-A time groups.

CONCLUSION

In patients undergoing CA for AF using dabigatran as a periprocedural anticoagulant, an O-A time of 8-24 h was associated with no bleeding complications. These data suggest that an O-A time of 8-24 h may be an appropriate option, especially in a low thromboembolic-risk patient.

Long-term efficacy and safety of anticoagulation after atrial fibrillation ablation: data from the JACRE registry

BACKGROUND

Catheter ablation (CA) is an important strategy for managing atrial fibrillation (AF). However, long-term anticoagulation strategies and clinical outcomes following CA, including thromboembolism and bleeding, have not yet been elucidated.

METHODS

We established a prospective registry, called the JACRE registry, for patients on rivaroxaban or warfarin administration who received CA for AF. The outcomes up to 30 days following the procedure were reported previously. The present study involved longer follow-up of patients enrolled in this registry to evaluate long-term anticoagulation strategies and clinical outcomes.

RESULTS

Data of 975 patients (rivaroxaban, n = 823; warfarin, n = 152) were collected from 27 institutes. Patient population had mean age 63.7 ± 10.3 years, 710 (72.8%) males, mean CHA₂DS₂-VASc score 1.9 ± 1.5, and mean follow-up period 28.7 ± 12.7 months after the index procedure. Anticoagulants were continued in 496 (50.9%) patients during the follow-up. Thromboembolism occurred in 3 patients, hemorrhagic stroke in 5, and major bleeding events in 9 (annualized event rate, 0.13%, 0.22%, and 0.40% per patient-year, respectively). There were no differences in the composite event rate of thromboembolism and International Society on Thrombosis and Haemostasis major bleeding between rivaroxaban and warfarin cohorts (0.53% and 0.55% per patient-year, respectively).

CONCLUSIONS

Long-term incidence of thromboembolism was extremely low in patients with AF treated with CA, while that of major bleeding was not especially low. Clinical Trials Registry: UMIN000032829 / UMIN000032830.

Peri-procedural novel oral anticoagulants dosing strategy during atrial fibrillation ablation: A meta-analysis

BACKGROUND

This study aimed at determining whether uninterrupted novel oral anticoagulant (UI-NOAC) would have similar rates of bleeding and thromboembolic events as minimally interrupted NOAC (MI-NOAC) at the time of ablation for atrial fibrillation (AF) as relevant studies are scarce.

METHODS

We searched through the PubMed, EMBASE, and Cochrane Library databases for prospective observational studies (POSs) or randomised controlled trials (RCTs) comparing UI-NOAC versus MI-NOAC from their establishment to January 2020. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to compare the pooled treatment effect.

RESULTS

Nine studies (three POSs and six RCTs) with 2578 patients were included in the final analysis (55% patients received MI-NOAC). No significant difference was found regarding the risk of major bleeding (OR 0.92, 95% CI 0.43-2.00, P = .84, I²   = 0%). Both groups were comparable in all subgroups ([Asians: OR 1.00, 95% CI 0.43-2.36, P = .99, I²   = 0%], [non-Asians: OR 0.64, 95% CI 0.11-3.88, P = .63, I²   = 0%], [RCTs: OR 0.85, 95% CI 0.37-1.97, P = .71, I²   = 0%], and [POSs: OR 0.52, 95% CI 0.19-12.01, P = .69, I²   = 0%]). The risk of minor bleeding (P = .88) or stroke (P = .69) was comparable between the groups. UI-NOAC resulted in a significant reduction in silent stroke (SS) (OR 0.44, 95% CI 0.23-0.83, P = .01, I²   = 72%). No significant difference was found in SS between once-daily and twice-daily NOACs (OR 0.91, 95% CI 0.63-1.33, P = .64, I²   = 0%) in the MI-NOAC group.

CONCLUSIONS

UI-NOAC, as a peri-procedural anticoagulation strategy for catheter ablation in AF, had similar safety compared with MI-NOAC, but was advantageous in terms of SS.

Comparison of effectiveness and safety between uninterrupted direct oral anticoagulants with and without switching to dabigatran in atrial fibrillation ablation

Introduction

Recent studies have demonstrated the feasibility of uninterrupted direct oral anticoagulants (DOACs) with a temporary switch to dabigatran (“dabigatran bridge”) for atrial fibrillation (AF) ablation. We compared the effectiveness and safety between uninterrupted DOACs with and without the “dabigatran bridge” in patients taking factor Xa inhibitors.

Methods

AF patients on factor Xa inhibitors (rivaroxaban/apixaban/edoxaban) undergoing catheter ablation were eligible (n = 348). Brain MRI was performed within 2 days after the procedure to detect silent cerebral events (SCEs). Rivaroxaban/apixaban/edoxaban were uninterruptedly used in 153 patients (Group 1); these DOACs were switched to dabigatran on the day of AF ablation in 195 patients (Group 2). After propensity score matching, the unfractionated heparin (UFH) amount and the activated clotting time (ACT) kinetics during the procedure, the SCE incidence, and the follow‐up complications (30 days, thromboembolism and major/minor bleeding) in the two groups were compared.

Results

Group 2 had higher initial ACT value and shorter time to optimal ACT (>300 seconds) than Group 1 (184 ± 36 s vs 145 ± 22 s, and 34 ± 29 s vs 43 ± 34 s, P < .05, respectively). Group 2 tended to require less amount of UFH to achieve optimal ACT than Group 1, but the total amount of UFH for the procedure was comparable. Group 2 had lower SCE incidence than Group 1 (16.2% vs 26.4%, P < .05). The prevalence of follow‐up complications was unchanged between the two groups.

Conclusions

Switching to dabigatran on the day of AF ablation decreases preclinical thromboembolic events with similar bleeding risk to uninterrupted factor Xa inhibitors.

Interrupted or Uninterrupted Oral Anticoagulants in Patients Undergoing Atrial Fibrillation Ablation

BACKGROUND AND PURPOSE

The safety and efficacy of uninterrupted, minimally interrupted (one dose skipped) or completely interrupted (24 h skipped) oral anticoagulant therapy in patients with atrial fibrillation (AF) ablation are poorly defined. We conducted a network meta-analysis to explore the effect of interrupted or uninterrupted oral anticoagulants in patients with AF undergoing ablation.

METHODS

The Cochrane Library, PubMed and Embase databases were systematically searched for studies comparing uninterrupted, minimally interrupted or completely interrupted non-vitamin K antagonist oral anticoagulants (NOACs) with continuous or interrupted warfarin in patients undergoing AF ablation.

RESULTS

Twelve randomized clinical trials (RCTs) with a total of 5597 patients with AF undergoing catheter ablation were included. For thromboembolism, minimally interrupted NOACs (OR 0.03, 95% CI 0.01-0.35), uninterrupted NOACs (OR 0.04, 95% CI 0.01-0.23) and continuous VKAs (OR 0.05, 95% CI 0.01-0.21) were better than interrupted warfarin. The risk of total bleeding appeared higher in the completely interrupted NOAC group compared with the minimally interrupted NOACs (OR 2.74, 95% CI 1.18-6.37), uninterrupted NOACs (OR 2.15, 95% CI 1.05-4.38) and uninterrupted warfarin (OR 2.04, 95% CI 1.02-4.08). To reduce the risk of total bleeding, minimally interrupted NOACs (OR 0.15, 95% CI 0.08-0.27), uninterrupted NOACs (OR 0.19, 95% CI 0.14-0.42) and uninterrupted warfarin (OR 0.24, 95% CI 0.15-0.39) were better than interrupted warfarin. In the event of major bleeding, there was no significant difference in the interrupted NOAC, uninterrupted NOAC, interrupted VKA and uninterrupted VKA groups.

CONCLUSIONS

These three NOAC strategies may have similar safety and efficacy in terms of thromboembolism and major bleeding complications. The total bleeding risk of completely interrupted oral anticoagulants is higher than that of uninterrupted and minimally interrupted NOACs. For thromboembolism, minimally interrupted NOACs, uninterrupted NOACs and continuous VKAs were better than interrupted warfarin.

Meta-analysis of the safety and efficacy of using minimally interrupted novel oral anticoagulants in patients undergoing catheter ablation for atrial fibrillation

PURPOSE

The ideal periprocedural anticoagulation strategy for patients being treated with a novel oral anticoagulant (NOAC) during catheter ablation (CA) for atrial fibrillation (AF) is unclear. We evaluated the safety and efficacy of using a minimally interrupted NOAC strategy versus an uninterrupted NOAC or vitamin K antagonist (VKA) strategy during AF ablation.

METHODS

The Cochrane Library, PubMed, and EMBASE databases were searched for randomized controlled or prospective observational studies that compared a minimally interrupted NOAC strategy with an uninterrupted NOAC or VKA strategy from the time of database establishment up to December 2019. The primary endpoints were major bleeding, minor bleeding, and symptomatic thromboembolism. The secondary endpoint was silent cerebral infarction (SCI) as detected by post-ablation brain magnetic resonance imaging (MRI). A measurement of treatment effect for the endpoint was reported as pooled odds ratio (OR) with 95% confidence interval (CI).

RESULTS

A total of 18 studies (6 randomized, 11 observational, and 1 randomized registry) with 6203 patients were included in the final analysis (47% of the patients received minimally interrupted NOAC). There was no significant difference between treatment groups regarding the risk for major bleeding (OR 1.04, 95% CI 0.69-1.57, P = 0.86, I² = 27%). Different stratification methods did not yield significant difference regarding the risk for major bleeding. There was no difference between groups regarding the risk for minor bleeding (P = 1.00) or symptomatic thromboembolism (P = 0.26). Brain MRI results showed that both uninterrupted NOAC (OR 0.44, 95% CI 0.23-0.83, P = 0.01, I² = 72%) and uninterrupted VKA (OR 0.48, 95% CI 0.24-0.97, P = 0.04, I² = 36%) produced a significant reduction in the rate of SCI when compared with minimally interrupted NOAC.

CONCLUSIONS

A periprocedural anticoagulation strategy of minimally interrupted NOAC is not superior to uninterrupted NOAC or VKA when used during AF ablation. There is evidence favoring the use of uninterrupted NOAC or VKA in terms of the risk for SCI.

Blood Coagulation Status during Cryofreezing Ablation and Effects of the Direct Anticoagulants Dabigatran and Edoxaban

Cryoballoon ablation is an established catheter-based approach to treat atrial fibrillation (AF). However, thromboembolic events cannot be avoided during cryoablation. There is little data regarding the blood coagulation status during freezing.The thrombin antithrombin complex (TAT) and prothrombin fragment 1+2 (F 1+2) of patient blood were measured during cryoballoon application when the cryoballoon temperature reached the nadir in 63 AF patients. TAT was also measured from porcine blood during cryoballoon freezing in 5 pigs.The TAT and F 1+2 increased from 6.60 ± 5.65 to 9.16 ± 7.28 ng/mL (P = 0.004) and from 279.6 ± 146.4 to 323.6 ± 169.1 pmol/L (P = 0.003) between the control and during freezing, respectively. The TAT increased from 0.46 to 0.87 ng/mL during freezing compared to that of pre-freezing (P < 0.05), and it returned to 0.39 ng/mL in 30 minutes after an intravenous edoxaban administration (N.S.).Dabigatran failed to exert sufficient anticoagulant effects during cryofreezing. In contrast, intravenous edoxaban seemed to provoke anticoagulation effects under extreme low temperature circumstances.