Activated clotting time monitoring during atrial fibrillation catheter ablation: Does the anticoagulant matter?

Abstract BACKGROUND: Studies indicate that uninterrupted anticoagulation is superior to interrupted anticoagulation in the periprocedural period during catheter ablation of atrial fibrillation and has better thromboembolic and hemorrhagic outcomes. Conversely, the few studies addressing the safety and efficacy of interrupted direct oral anticoagulant regimens during catheter ablation of atrial fibrillation are limited by small samples, short follow-up periods, rare events, and variable outcomes. The purpose of this meta-analysis was to compare interrupted and uninterrupted direct oral anticoagulation during catheter ablation of atrial fibrillation.METHODS: A systematic search into PubMed, EMBASE, and the Cochrane databases were performed and five studies were selected that directly that directly compared interrupted versus uninterrupted anticoagulation before ablation and reported procedural outcomes and embolic and bleeding events. The primary outcome of the study was major adverse cerebrocardiovascular events which was a composite of stroke/ transient ischemic attacks and major bleedings, total bleeding which was a composite of major and minor bleedings and silent cerebral events.RESULTS The meta-analysis included 840 patients with uninterrupted anticoagulation and 938 patients with interrupted anticoagulation. Median follow-up was 30 days. Baseline parameters were similar between groups. Activated clotting time before first heparin bolus was significantly longer with uninterrupted anticoagulation (P=.006), whereas mean activated clotting time was similar between the 2 groups (P=.19). Total heparin dose needed was significantly higher with interrupted anticoagulation (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 cerebrocardiovascular event (P=.40) and total bleeding (P=.55) rates between groups. Silent cerebral events were significantly more frequent with interrupted anticoagulation (log odds ratio, ‒0.90; 95% CI, ‒1.59 to ‒0.22; P<.01; I2, 33%). Rates of major bleeding, minor bleeding, pericardial effusion, cardiac tamponade, and puncture complications were similar between groups.CONCLUSIONS Uninterrupted anticoagulation during atrial fibrillation ablation has similar bleeding event rates, procedural times, and mean activated clotting times as interrupted anticoagulation, with fewer silent cerebral events.

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P369Comparison of three methods of activated clotting time (ACT) measurement during catheter ablation for atrial fibrillation

EP Europace ◽

10.1093/europace/euy015.180 ◽

2018 ◽

Vol 20 (suppl_1) ◽

pp. i64-i65

Author(s):

V Bulkova ◽

M Fiala ◽

N Rotter ◽

A Mullerova ◽

L Rybka ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Clotting Time ◽

Activated Clotting Time

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Running after Activated Clotting Time Values in Patients Receiving Direct Oral Anticoagulants: A Potentially Dangerous Race. Results from a Prospective Study in Atrial Fibrillation Catheter Ablation Procedures

Journal of Clinical Medicine ◽

10.3390/jcm10184240 ◽

2021 ◽

Vol 10 (18) ◽

pp. 4240

Author(s):

Karim Benali ◽

Julien Verain ◽

Nefissa Hammache ◽

Charles Guenancia ◽

Darren Hooks ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Oral Anticoagulants ◽

Direct Oral Anticoagulants ◽

Clotting Time ◽

Af Ablation ◽

Activated Clotting Time ◽

Real Increase ◽

A Prospective Study ◽

The Relationship

Background: Activated Clotting Time (ACT) guided heparinization is the gold standard for titrating unfractionated heparin (UFH) administration during atrial fibrillation (AF) ablation procedures. The current ACT target (300 s) is based on studies in patients receiving a vitamin K antagonist (VKA). Several studies have shown that in patients receiving Direct Oral Anticoagulants (DOACs), the correlation between ACT values and UFH delivered dose is weak. Objective: To assess the relationship between ACT and real heparin anticoagulant effect measured by anti-Xa activity in patients receiving different anticoagulant treatments. Methods: Patients referred for AF catheter ablation in our centre were prospectively included depending on their anticoagulant type. Results: 113 patients were included, receiving rivaroxaban (n = 30), apixaban (n = 30), dabigatran (n = 30), and VKA (n = 23). To meet target ACT, a higher UFH dose was required in DOAC than VKA patients (14,077.8 IU vs. 9565.2 IU, p < 0.001), leading to a longer time to achieve target ACT (46.5 min vs. 27.3 min, p = 0.001). The correlation of ACT and anti-Xa activity was tighter in the VKA group (Spearman correlation ρ = 0.53), compared to the DOAC group (ρ = 0.19). Despite lower ACT values in the DOAC group, this group demonstrated a higher mean anti-Xa activity compared to the VKA group (1.56 ± 0.39 vs. 1.14 ± 0.36; p = 0.002). Conclusion: Use of a conventional ACT threshold at 300 s during AF ablation procedures leads to a significant increase in UFH administration in patients treated with DOACs. This increase corresponds more likely to an overdosing than a real increase in UFH requirement.

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The impact of oral direct thrombin inhibitors on activated clotting time during catheter ablation in patients with atrial fibrillation

EP Europace ◽

10.1093/europace/euab116.159 ◽

2021 ◽

Vol 23 (Supplement_3) ◽

Author(s):

T Mine ◽

R Kitagaki ◽

E Fukuhara ◽

M Ishihara

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Thrombin Inhibitors ◽

Bleeding Complications ◽

Direct Thrombin Inhibitors ◽

Clotting Time ◽

Heparin Dose ◽

Activated Clotting Time ◽

Heparin Administration ◽

The Impact

Abstract Funding Acknowledgements Type of funding sources: None. Background Direct thrombin inhibitors (DTIs) unlike factor Xa-inhibitors (Xa-inhibitors) is associated with fewer bleeding complications than warfarin in patients who had catheter ablation (CA) for atrial fibrillation (AF). However, the mechanisms remains unclear, and activated clotting time (ACT) is used to control heparin-dose for thromboembolic prevention during CA. Methods: We retrospectively studied 543 patients taking direct oral anticoagulant (DOAC) who underwent CA for AF (375 males, age 67 ± 10, 251 non-paroxysmal AF, 142 DTIs). Patients with off-label usage of DOAC were excluded. ACT was measured before (Pre-ACT) and after (post-ACT) initial heparin administration (3000U + 100U/kg), and total heparin-dose was evaluated. Results: Pre-ACT and post-ACT were extended in patients with DTIs (150 ± 21 vs 123 ± 15; P < 0.0001 and 322 ± 39 vs 309 ± 42 sec; P = 0.0013). Patients with Xa-inhibitors required higher total heparin-dose (199 ± 43 vs 175 ± 34 U/kg; P < 0.0001). During and after CA, none had thromboembolic events and 14 patients (3 DTIs, 11 Xa-inhibitor) showed bleeding events (Figure). Conclusions: ACT is extended in patients taking DTIs. Xa-inhibitors might have anticoagulant effects which are not reflected in ACT. Abstract Figure.

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Management of Intraprocedural Anticoagulation in Patients on Non-Vitamin K Antagonist Oral Anticoagulants Undergoing Catheter Ablation for Atrial Fibrillation

Circulation ◽

10.1161/circulationaha.117.033326 ◽

2018 ◽

Vol 138 (6) ◽

pp. 627-633 ◽

Cited By ~ 7

Author(s):

Anne-Céline Martin ◽

Anne Godier ◽

Kumar Narayanan ◽

David M. Smadja ◽

Eloi Marijon

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Unfractionated Heparin ◽

Vitamin K ◽

Vitamin K Antagonists ◽

Oral Anticoagulants ◽

Vitamin K Antagonist ◽

Clotting Time ◽

Anticoagulation Management ◽

Activated Clotting Time

Catheter ablation has gained a prominent role in the management of atrial fibrillation (AF), with recent data providing positive evidence on hard outcomes, including hospitalization and mortality. Ablation, however, exposes the patient to a rather unique situation, combining risks for both major bleeding and thromboembolic events. In this setting, the critical importance of rigorous anticoagulation during the procedure has been underlined, and the latest international guidelines now recommend performing AF catheter ablation with uninterrupted non-vitamin K antagonist oral anticoagulants (NOACs) and concomitant administration of unfractionated heparin adjusted to achieve and maintain a target activated clotting time of ≥300 seconds. Whereas observational studies and randomized controlled trials support the safety and efficacy of uninterrupted NOAC strategy for AF catheter ablation, recent experiences have questioned this point, showing a greater unfractionated heparin requirement in NOAC-treated patients compared with vitamin K antagonists–treated patients to achieve the target activated clotting time. Important gaps in evidence regarding optimal intraprocedural anticoagulation management need to be acknowledged. A thorough appreciation of the physiology of anticoagulation during AF catheter ablation and the relevant differences between vitamin K antagonists and NOACs is required, while also understanding the limitations of activated clotting time measurement with regard to accurate intraprocedural anticogulation monitoring. This review aims to provide a critical look at this relatively ignored aspect of AF catheter ablation, especially pitfalls in NOAC monitoring, and to identify gaps in knowledge that need to be addressed in the near future.

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Activated Clotting Time Monitoring during Atrial Fibrillation Catheter Ablation: Does the Anticoagulant Matter?

Journal of Clinical Medicine ◽

10.3390/jcm9020350 ◽

2020 ◽

Vol 9 (2) ◽

pp. 350 ◽

Cited By ~ 5

Author(s):

Anne-Céline Martin ◽

Maeva Kyheng ◽

Vincent Foissaud ◽

Alain Duhamel ◽

Eloi Marijon ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Oral Anticoagulants ◽

Direct Oral Anticoagulants ◽

Vitamin K Antagonist ◽

Strongly Correlated ◽

Clotting Time ◽

Response Curves ◽

Activated Clotting Time

Atrial fibrillation (AF) catheter ablation is performed in patients receiving direct oral anticoagulants (DOACs) with intra-procedural unfractionated heparin (UFH) administration to achieve activated clotting time (ACT) at 300 s, as for vitamin K antagonist (VKA). We determined whether ACT monitoring might be transposed from VKA to DOAC-treated patients. Blood was taken from 124 patients receiving uninterrupted dabigatran, rivaroxaban, apixaban, or VKA or being untreated. DOAC concentration or INR (VKA) were measured. ACT was determined at baseline, and after spiking with UFH doses equivalent to 1000, 2500, 5000 and 10000 IU in vivo. At baseline, anticoagulants prolonged ACT differently, ACT was longer with dabigatran and shorter with apixaban despite similar concentrations. ACT strongly correlated with INR and dabigatran concentration, but not with apixaban or rivaroxaban concentrations. Moreover, UFH effects on ACT prolongation depended on the anticoagulant: dose-response curves in samples with VKA and dabigatran were parallel whereas ACT prolongation in response to UFH was significantly smaller with rivaroxaban and especially apixaban. Therefore, UFH to achieve ACT at 300 s might be transposed from VKA to uninterrupted dabigatran-treated patients but not to patients receiving FXa-inhibitors, especially apixaban. Targeting 300 s might expose to UFH overdosing and bleeding, questioning the current anticoagulation strategy.

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