By David Ramsey

Patients with atrial fibrillation (AF) who need anticoagulation before electrical cardioversion, may benefit from treatment with edoxoban - a non-vitamin K antagonist (VKA) oral anticoagulant (NOAC).

According to results of the ENSURE-AF trial, edoxoban is as effective and safe as the more standard therapy that uses VKAs, Andreas Goette, investigator of the study told delegates at ESC Congress 2016 in Rome, Italy. The study is published in The Lancet.

“While VKA anticoagulation works well, it has a major limitation in that it requires regular monitoring and dose adjustment to ensure that patients reach anticoagulation targets,” explained Prof Goette. This can sometimes delay cardioversion for several weeks.

“At a practical level, our study results show that newly diagnosed non-anticoagulated AF patients can start edoxaban as early as two hours prior to their cardioversion procedure if they have access to transoesophageal echocardiography (TEE) or 3 weeks prior without.”

The ENSURE-AF trial, >2000 patients strong, from 19 countries in Europe and the US, suggests that the new generation of direct oral anticoagulants (DOACs) could potentially replace the cumbersome warfarin approach. In the case of edoxaban, the trial offers hope that the entire process of anticoagulation with AF cardioversion may routinely become as simple as starting with one pill 2 hours before the procedure, delegates were told.

Edoxaban was previously shown to be safe and effective compared to standard VKA therapy (enoxaparin/warfarin) among patients with AF in the ENGAGE AF-TIMI 48 study, but the impact of electrical cardioversion was not systematically assessed in that study.

ENSURE-AF, the largest randomised clinical trial of anticoagulation for cardioversion in patients with AF, “provides the largest prospective trial data for a NOAC in this clinical setting,” noted Prof Goette

A total of 1,095 patients were randomised to receive edoxaban, while the remaining 1,104 received enoxaparin/warfarin (dosing varied depending on patient characteristics).

Of these 988 (90·2%) and 966 (87·5%) patients, respectively, were cardioverted either electrically or spontaneously, some with the use of transoesophageal echocardiography (TEE).

The primary efficacy objective of this study was to compare the incidences of the composite endpoint of stroke, systemic embolic event (SEE), myocardial infarction (MI) and cardiovascular (CV) death between the two groups at day 28 (ITT analysis).

This endpoint occurred at a comparable rate in both groups: 0·5% patients in the edoxaban arm vs. 1·0% in the enoxaparin/warfarin arm (OR=0·46; 95% CI, 0·12–1·43). The primary safety outcome was a composite endpoint of major and clinically relevant non-major (CRNM) bleeding events at 30 days. This also occurred at a comparable rate 1·5%and 1·0% respectively (OR=1·48; 95% CI, 0·64–3·55).

In short, “edoxaban had similar rates of major bleeding and thromboembolism compared to well-managed, optimized enoxaparin/warfarin therapy. The results were similar whether TEE-guidance was used or not, whether patients had received prior anticoagulation or not, and in patients with a broad range of associated comorbidities.”