November 13, 2007Circulation251 citationsOpen Access
View Full PaperAtrial Fibrillation Ablation in Patients With Therapeutic International Normalized Ratio
Key Result
Continuation of warfarin during pulmonary vein ablation resulted in 0 ischemic strokes and 5.3% minor bleeding, compared to 1-2% strokes and 19-21.9% minor bleeding with enoxaparin bridging.
Study Design
Type
Cohort (n=355)
Structured PICO
Does continuation of warfarin to maintain therapeutic INR improve safety compared to enoxaparin bridging in patients undergoing atrial fibrillation ablation?
P
Population
355 consecutive patients undergoing pulmonary vein antrum isolation for persistent atrial fibrillation, evaluated for periprocedural anticoagulation strategies.
E
Exposure
Continuation of warfarin to maintain international normalized ratio (INR) between 2 and 3.5 throughout pulmonary vein ablation.
C
Comparator
Warfarin stopped 3 days before ablation and bridged with enoxaparin (either 1 mg/kg twice daily or 0.5 mg/kg twice daily).
O
Outcome
Ischemic stroke, minor bleeding (hematoma not requiring intervention), and major bleeding (cardiac tamponade, hematoma requiring intervention, or bleeding requiring blood transfusion).safety
Performing atrial fibrillation ablation without interrupting warfarin therapy is a safe alternative to enoxaparin bridging, potentially reducing periprocedural bleeding and stroke.
Abstract
BACKGROUND: The best approach to management of anticoagulation before and after atrial fibrillation ablation is not known. METHODS AND RESULTS: We compared outcomes in consecutive patients undergoing pulmonary vein antrum isolation for persistent atrial fibrillation. Early in our practice, warfarin was stopped 3 days before ablation, and a transesophageal echocardiogram was performed to rule out clot. Enoxaparin, initially 1 mg/kg twice daily (group 1) and then 0.5 mg/kg twice daily (group 2), was used to "bridge" patients after ablation. Subsequently, warfarin was continued to maintain the international normalized ratio between 2 and 3.5 (group 3). Minor bleeding was defined as hematoma that did not require intervention. Major bleeding was defined as either cardiac tamponade, hematoma that required intervention, or bleeding that required blood transfusion. Pulmonary vein ablation was performed in 355 patients (group 1=105, group 2=100, and group 3=150). More patients had spontaneous echocardiographic contrast in groups 1 and 2. One patient in group 1 had an ischemic stroke compared with 2 patients in group 2 and no patients in group 3. In group 1, 23 patients had minor bleeding, 9 had major bleeding, and 1 had pericardial effusion but no tamponade. In group 2, 19 patients had minor bleeding, and 2 patients developed symptomatic pericardial effusion with need for pericardiocentesis 1 week after discharge. In group 3, 8 patients developed minor bleeding, and 1 patient developed pericardial effusion with no tamponade. CONCLUSIONS: Continuation of warfarin throughout pulmonary vein ablation without administration of enoxaparin is safe and efficacious. This strategy can be an alternative to bridging with enoxaparin or heparin in the periprocedural period.