362 Periprocedural Anticoagulation for Atrial Fibrillation Ablation M. EYMAN MORTADA, M.D., K. CHANDRASEKARAN, M.D., VIKRAM NANGIA, M.D., ANWER DHALA, M.D., ZALMEN BLANCK, M.D., RYAN COOLEY, M.D., ATUL BHATIA, M.D., CAROL GILBERT, R.N., MASOOD AKHTAR, M.D., and JASBIR SRA, M.D. From the Electrophysiology Laboratories of Aurora Sinai/Aurora St. Luke’s Medical Centers, University of Wisconsin School of Medicine and Public Health-Milwaukee Clinical Campus, Milwaukee, Wisconsin, USA AF and Anticoagulation. Background: Catheter ablation for atrial fibrillation (AF) can increase risk of left atrial (LA) thrombi and stroke. Optimal periprocedural anticoagulation has not been determined. Objective: We report the role of administering warfarin and aspirin without low molecular weight heparin in patients undergoing AF ablation. Methods: A total of 207 patients underwent ablation for AF. Transesophageal echocardiography (TEE) guided transseptal puncture and ruled out clot in the LA. After first puncture, the sheath was flushed with heparin (5,000 Units/mL). After second puncture, a bolus of 80 units/kg of heparin was given, followed by an infusion to maintain activated clotting time (ACT) around 300–350 seconds. Warfarin was stopped and aspirin was started (325 mg/day) 3 days preprocedure. Warfarin was restarted on the day of the procedure. Both medications were continued for 6 weeks postablation. Warfarin was continued for 6 months in patients with prior history of persistent or recurrent AF. Thirty-seven patients who showed smoke in the LA on TEE were given low molecular weight heparin postprocedure until international normalized ratio (INR) was therapeutic. Results: Thirty-two patients had persistent and 175 had paroxysmal AF; 87 were cardioverted during ablation. Two patients had transient ischemic attack (TIA) on the sixth and eighth days, respectively, following ablation, with complete recovery. Both had subtherapeutic INRs. Conclusion: In patients without demonstrable clot or smoke in the LA, starting aspirin 3 days prior and warfarin immediately post-radiofrequency ablation, without low molecular weight heparin, with metic- ulous anticoagulation during the procedure, appears to be a safe mode of anticoagulation. (J Cardiovasc Electrophysiol, Vol. 19, pp. 362-366, April 2008) atrial fibrillation, ablation, stroke, warfarin, aspirin Introduction Atrial fibrillation (AF) is the most common sustained car- diac rhythm disturbance and one of the major causes of mor- tality and morbidity in the world, with thromboembolism being a common complication. 1-3 AF ablation should po- tentially reduce the incidence of stroke as it eliminates the substrate for thromboembolism. The overall peri-operative risk of thromboembolic event was reported to be around 1.6– 2.2% in focal AF ablations 4-7 and up to 7% in linear AF ablations. 8 Optimal anticoagulation pre- and post-AF ablation has not been determined, though many authors suggest low molec- ular weight heparin. We report on the role of administering warfarin and aspirin without low molecular weight heparin in patients undergoing AF ablation. Address for correspondence: Jasbir Sra, M.D., 2801 W. Kinnickinnic River Pkwy 777, Milwaukee, WI 53215. Fax: 414-649-5769; E-mail: bdanek@hrtcare.com Manuscript received 8 August 2007; Revised manuscript received 3 October 2007; Accepted for publication 26 October 2007. doi: 10.1111/j.1540-8167.2007.01071.x Methods Study Population Two hundred and seven consecutive patients who un- derwent RFA for AF were included in the study. All pa- tients had documented symptomatic AF prior to the proce- dure. They were refractory to at least one antiarrhythmic medication. One hundred and seventy-nine (86.5%) pa- tients were on anticoagulation therapy with warfarin prior to ablation. Preprocedure Evaluation All patients who were on warfarin therapy, including those in persistent AF, stopped their anticoagulation medication 3 days prior to the procedure. During those 3 days, all patients received aspirin 325 mg orally once a day without bridging to low molecular weight heparin. Achieving an INR equal to or less than 2.0 was required to proceed. Patients stopped all antiarrhythmic medications 3 days prior to the procedure, except amiodarone, which was stopped 2 to 4 weeks prior to the procedure. Prior to the procedure, all patients underwent a contrast- enhanced CT scan of the chest (16 or 64-slice, LightSpeed Volume CT, GE Healthcare, Waukesha, WI, USA). The