Catheter Ablation for Atrial Fibrillation on Uninterrupted Warfarin: Can It Be Done Without Echo Guidance?

INTRODUCTION: Catheter ablation for atrial fibrillation is an effective treatment for symptomatic patients who have failed drug therapy. Recent studies using intracardiac echocardiography have demonstrated that ablation can be performed safely on uninterrupted warfarin and may be superior to bridging low molecular weight heparin (LMWH). We sought to assess the safety of an uninterrupted warfarin protocol using a simplified ablation protocol in a prospective controlled study. METHODS: Two anticoagulation regimes for patients undergoing catheter ablation for atrial fibrillation were evaluated--a bridging LMWH group and an uninterrupted warfarin group. Bleeding complications were compared between the 2 groups. RESULTS: In total 198 patients were evaluated (109 bridging LMWH, 89 uninterrupted warfarin). The preprocedure INR in the LMWH group (mean age 60. 6 years, 72% male) was 1. 2 ± 0. 3 compared to 2. 3 ± 0. 5 in the uninterrupted warfarin group (mean age 60. 9 years, 69% male). The primary outcome (a composite of major and minor bleeding complications) was observed in 78% in the LMWH group compared to 56% in the warfarin group (P = 0. 001), mainly due to increased pain at the venous access site (41% vs 16%, P = 0. 001). Two patients undergoing ablation on warfarin required pericardiocentesis for cardiac tamponade. Drug costs were lower in the warfarin group (64. 77 ± 31. 86 vs 20. 76 ± 15. 60, P = 0. 005), but the overall cost of treatment per patient (including bed occupancy costs) was similar in the LMWH group compared to the warfarin group (883. 96 ± 278. 78 vs 816. 59 ± 182. 72, P = 0. 06). CONCLUSION: Catheter ablation for atrial fibrillation can be performed safely on uninterrupted warfarin without intracardiac echocardiography, with a reduced risk of bleeding complications.