Abstract 10868: Diffusion Magnetic Cerebral Imaging (dMRI) Pre and 24 Hours Post Ablation of Atrial Fibrillation: Results on Therapeutic Anticoagulation with Coumadin
Introduction: Catheter ablation of atrial fibrillation (AF) carries the potential risk of peri-procedural symptomatic and silent ischemic stroke. We sought to determine the prevalence of positive dMRI when performing catheter ablation of AF without warfarin discontinuation.
Methods: Data from 2 centers performing ablation for AF with the same anticoagulation protocol have been prospectively collected. All patients were on warfarin before the procedures to achieve 4/6 weeks of therapeutic INRs before ablation. All the procedures were performed without Warfarin discontinuation and with patients on “therapeutic INR”. A bolus of 10000 UI was given prior to transeptal puncture in all patients. All patients maintained ACT above 300 secs during the entire procedure. During the ablation if sinus rhythm (SR) could not be achieved, electrical cardioversion was utilized to achieve SR. All of the patients underwent preprocedural and postablation (within 24 hours) dMRI.
Results: The patient population consisted of 51 consecutive patients (59±13 years, 76% male, 32% paroxysmal, 4% persistent, 64% long-standing AF, LA size 44±4 mm, EF 62±6, 22 % CHADS2 ≥2). The mean INR was 2.5± 3. To restore SR, cardioversion was utilized in 24 (47%) patients. Preprocedural dMRI showed evidence of pre-procedure silent cerebral events in 11 (22%) patients; all of them had single cortical lesion. Post-ablation dMRI was positive for asymptomatic and silent new ischemic lesion in one (1.9%) patient, who was one of the 11 patients with baseline lesion; the new lesion was present on the right frontal cortex and resolved spontaneously at a 3 months repeat dMRI. In this patient the pre-transeptal bolus of heparin was not administered. The pre-procedural INR for this patient was 2.14 and the ACT was 260 secs which is below the recommended value.
Conclusion: These preliminary results demonstrate that when performing catheter ablation of AF with “therapeutic” INR values, the risk for silent ischemic lesion as detected by dMRI is very low even if cardioversion is utilized to restore SR. Administration of heparin bolus before transeptal and ACT above 300 secs may also be important to eliminate the risk of silent embolic events. Further analysis in a wider population is necessary to confirm our data.
- © 2011 by American Heart Association, Inc.