Catheter ablation for AF improves global thrombotic profile and enhances fibrinolysis

Patients with atrial fibrillation (AF) are at increased risk of thrombotic events despite oral anticoagulation (OAC). Radiofrequency catheter ablation (RFCA) can restore and maintain sinus rhythm (SR) in patients with AF. To assess whether RFCA improves thrombotic status. 80 patients (71% male, 64 ± 12y) with recently diagnosed AF, on OAC and scheduled to undergo RFCA or DC cardioversion (DCCV) were recruited. Thrombotic status was assessed using the point-of-care global thrombosis test (GTT), before, and 4-6 weeks after DCCV and 3 months after RFCA. The GTT first measures the time taken for occlusive thrombus formation (occlusion time, OT), while the second phase of the test measures the time taken to spontaneously dissolve this clot through endogenous thrombolysis (lysis time, LT). 3 months after RFCA, there was a significant reduction in LT (1994s [1560; 2475] vs. 1477s [1015; 1878]) in those who maintained SR, but not in those who reverted to AF. At follow-up, LT was longer in those in AF compared to those in SR (AF 2966s [2038; 3879] vs. SR 1477s [1015; 1878]). RFCA resulted in no change in OT value, irrespective of rhythm outcome. Similarly, there was no change in OT or LT in response to DCCV, irrespective of whether SR was restored. Successful restoration and maintenance of SR following RFCA of AF is associated with improved global thrombotic status with enhanced fibrinolysis. Larger studies are required to confirm these early results and investigate whether improved thrombotic status translates into fewer thromboembolic events.