INTRODUCTION: Oral anticoagulation (OAC) is indicated for patients with atrial fibrillation (AF) and atrial flutter (AFL) with a CHA2DS2-VASc score ≥ 2 for men and ≥3 for women. This is regardless of successful catheter ablation for their arrhythmia. Studies have mainly focused on AF, and little is known regarding use of OAC in AFL patients following catheter ablation.

PURPOSE: To describe discontinuation of OAC in a national cohort of patients who have undergone first-time cavo-tricuspid isthmus ablation (CTIA) for AFL.

METHODS: We identified patients undergoing first-time CTIA during the period 2010-2016 using the Danish National Ablation Registry. Information on comorbidities and OAC use were gathered using the Danish National Patient Registry and the Danish National Prescription Registry. Patients were followed until March 1st, 2018.

RESULTS: We identified 2409 consecutive patients. Median age was 66 (IQR 58-72) years, and 1952 (81%) were men. During mean follow-up of 4 ± 1.7 years, 723 (30%) patients discontinued OAC. Patients discontinuing OAC were younger, had less comorbidity, and a lower CHA2DS2-VASc score. During follow-up, 252 (10%) patients died, and 112 (5%) patients had a stroke. Incidence of both these events increased with increasing age and CHA2DS2-VASc score. In adjusted analysis, we observed higher mortality (p < 0.0001) in patients discontinuing OAC, while stroke rate was not significantly higher (p = 0.21).

CONCLUSION: In this national cohort of patients who have undergone first-time CTIA, patients discontinuing OAC treatment were younger and had less comorbidities. Patients remain at elevated risk of death and stroke/TIA, increasing with their age and CHA2DS2-VASc score.