Yonsei Med J.  2014 Sep;55(5):1238-1245. 10.3349/ymj.2014.55.5.1238.

Safety and Efficacy of Switching Anticoagulation to Aspirin Three Months after Successful Radiofrequency Catheter Ablation of Atrial Fibrillation

• Uhm JS
• Won H
• Joung B
• Nam GB
• Choi KJ
• Lee MH
• Kim YH
• Pak HN

• KMID: 1799486
• DOI: http://doi.org/10.3349/ymj.2014.55.5.1238

Abstract

PURPOSE
Although current guidelines recommend continuing the same antithrombotic strategy regardless of rhythm control after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF), anticoagulation has a risk of major bleeding. We evaluated the safety of switching warfarin to aspirin in patients with successful AF ablation.
MATERIALS AND METHODS
Among 721 patients who underwent RFCA of AF, 608 patients (age, 57.3+/-10.9 years; 77.0% male, 75.5% paroxysmal AF) who had no evidence of AF recurrence at 3 months post-RFCA were included. We compared the thromboembolic and hemorrhagic events in patients for whom warfarin was switched to aspirin (ASA group; n=296) and patients who were kept on warfarin therapy (W group; n=312).
RESULTS
There were no significant differences in CHA2DS2-VASc or HAS-BLED scores between the groups. In 30 patients in the ASA group and 37 patients in W group, AF recurred and warfarin was restarted or maintained during the 18.0+/-12.2 months of follow-up. There were no significant differences in thromboembolic (0.3% vs. 1.0%, p=0.342) and major bleeding incidences (0.7% vs. 0.6%, p=0.958) between ASA and W groups during the follow-up period. In the 259 patients with a CHA2DS2-VASc score > or =2, there were no significant differences in thromboembolism (0.8% and 2.2%, p=0.380) or major bleeding incidences (0.8% and 1.4%, p=0.640) between ASA and W groups.
CONCLUSION
Switching warfarin to aspirin 3 months after successful RFCA of AF could be as safe and efficacious as long-term anticoagulation even in patients with CHA2DS2-VASc score > or =2. However, strict rhythm monitoring cannot be overemphasized.

Keyword

Anticoagulation; aspirin; atrial fibrillation; catheter ablation

MeSH Terms

Aged
Anticoagulants/*therapeutic use
Aspirin/administration & dosage/*therapeutic use
Atrial Fibrillation/*surgery
Catheter Ablation
Female
Hemorrhage/epidemiology
Humans
Kaplan-Meier Estimate
Male
Middle Aged
Postoperative Complications/epidemiology
Retrospective Studies
Risk Assessment
Thromboembolism/epidemiology
Treatment Outcome
Warfarin/administration & dosage/*therapeutic use
Anticoagulants
Aspirin
Warfarin

Figure

• 

  Fig. 1 Flow diagram and numbers of patients. AF, atrial fibrillation; RFCA, radiofrequency catheter ablation.

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  Fig. 2 Thromboembolic and major bleeding event-free survival by Kaplan-Meier method in all patients (A) and the patients with CHA2DS2-VASc score ≥2 (B) in ASA (solid line) and W (dotted line) groups.

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