The use of anticoagulation during the periprocedure period of atrial fibrillation ablation

Randomized Comparison of Continuous Versus Intermittent Heparin Infusion During Catheter Ablation of Atrial Fibrillation

OBJECTIVES

This study tested the hypothesis that continuous heparin infusions would be favorable for maintaining heparin concentrations during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF).

BACKGROUND

Heparin infusions are essential for RFCA of AF. There is a paucity of data on the details for the optimal heparin infusion during RFCA of AF.

METHODS

A total of 333 patients undergoing AF ablation were consecutively enrolled and randomized to intermittent or continuous heparin infusion. A heparin bolus of 100 U/kg was injected just prior to transseptal puncture. The heparin concentration necessary to maintain an optimal activated clotting time (ACT) (300 to 400 s) was determined and checked every 30 min during the procedure. The primary endpoint of the study was the frequency of the maintenance of an optimal intraprocedural ACT.

RESULTS

The frequency of an optimal ACT in the continuous group was significantly higher than that in the intermittent group (64.0% vs. 57.6%, respectively, p < 0.01), whereas the total heparin level was significantly lower in the continuous group (13,162 ± 4,634 U vs. 15,837 ± 5,243 U, respectively, p < 0.01). The standard deviation of the ACT was significantly smaller in the continuous group than in the intermittent group (49 ± 30 vs. 33 ± 18, respectively, p < 0.01). Ninety-six patients had new oral anticoagulants (NOACs) before the procedure, and an optimal ACT at the first ACT check was less frequent than in patients taking warfarin (12.5% vs. 59.1%, respectively, p < 0.01). There were no significant differences in periprocedural bleeding or thromboembolic complications between the groups.

CONCLUSIONS

During AF ablation, a continuous heparin infusion was superior to an intermittent heparin infusion for maintaining an optimal ACT range. (Randomized Comparison of Continuous and Intermittent Heparin Infusion During Catheter Ablation of Atrial Fibrillation [COHERE]; NCT01935557).

Safety and efficacy of dabigatran compared with warfarin for patients undergoing radiofrequency catheter ablation of atrial fibrillation: a meta-analysis

BACKGROUND

The safety and efficacy of dabigatran in the periprocedural period for patients undergoing atrial fibrillation ablation is not well established. We conducted a meta-analysis of the periprocedural use of dabigatran vs warfarin (with or without heparin bridging).

METHODS

A literature search was performed using multiple databases. Outcomes were (1) major bleeding; (2) minor bleeding; and (3) thromboembolic events. Odds ratios (ORs) were reported for dichotomous variables.

RESULTS

Eleven controlled studies (9 cohorts, 1 randomized controlled trial and 1 case-control study; 3841 patients) were identified. Dabigatran was used in 1463 patients, uninterrupted in 223 and held up to 36 hours in the remainder. No significant differences were noted in major bleeding rates between dabigatran and warfarin groups (1.9% vs. 1.6%; OR, 1.04 [95% confidence interval (CI), 0.51-2.13]; P = 0.92). Cardiac tamponade was observed in 1.4% in dabigatran vs 1.1% in warfarin groups (OR, 1.1; 95% CI, 0.55-2.11; P = 0.82). Similar rates for dabigatran vs. warfarin were reported for minor bleeding (3.8% vs. 4.5%; OR, 0.85; 95% CI, 0.58-1.25; P = 0.40), hematoma (2% vs. 2.7%; OR, 0.67; 95% CI, 0.41-1.08; P = 0.1), and thromboembolic events (0.6% vs. 0.1%; OR, 2.51; 95% CI, 0.78-8.11; P = 0.12).

CONCLUSIONS

This meta-analysis suggests that dabigatran and warfarin have similar safety and efficacy overall for periprocedural anticoagulation in patients undergoing radiofrequency atrial fibrillation ablation. Signals were seen favouring dabigatran (for hematomas) and warfarin (for thromboembolic events), but neither was statistically significant because of low event rates. More high-quality data are required to definitively compare the 2 strategies.

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.