Catheter ablation for AF improves global thrombotic profile and enhances fibrinolysis

© The Author(s) 2017. This article is an open access publication. The final authenticated version is available online at: https://doi.org/10.1007/s11239-017-1548-3Patients 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.Peer reviewedFinal Published versio

Novel antithrombotic agents for atrial fibrillation

Copyright 2012 Elsevier B.V., All rights reserved.Atrial fibrillation (AF) is the most common cardiac arrhythmia. It is estimated that 1 in 4 individuals aged 40 years or above will develop at least 1 episode of AF during their lifetime. Stroke is a leading cause of serious, long-term disability and death, and a major socioeconomic burden in developed countries. The major risk factor for thromboembolic stroke is AF. Oral antithrombotic treatment for AF patients has been limited to vitamin K antagonists for more than 60 years. Treatment with warfarin can reduce, but fails to abolish thromboembolic stroke associated with AF. Despite anticoagulation, patients with AF are at increased stroke risk. Furthermore, warfarin has important limitations namely, the limited time in therapeutic range, the need for INR monitoring, risk of major bleeding including stroke, and drug interactions. Recently there have been very exciting and important new advances in thromboprophylaxis for AF. Novel oral agents have been developed and evaluated clinically. These include direct thrombin inhibitors (dabigatran etexilate), oral selective factor Xa inhibitors (rivaroxaban, apixaban and edoxaban) and PAR-1 inhibitors (vorapaxar and atopaxar). Some of the new drugs have demonstrated promising results in the clinical studies, they are convenient in use and do not require monitoring. The downsides are lack of antidotes or specific blood assays to monitor the anticoagulant effect. This review evaluates traditional and novel approaches to thromboprophylaxis in patients with AF.Peer reviewe

Comparison of De-escalation of DAPT Intensity or Duration in East Asian and Western Patients with ACS Undergoing PCI: A Systematic Review and Meta-analysis

© 2023, Thieme. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1055/s-0043-57030Background Guideline-recommended dual antiplatelet therapy (DAPT; aspirin plus prasugrel/ticagrelor) for 12 months in acute coronary syndrome (ACS) patients increases bleeding, with East Asians (EAs) exhibiting higher bleeding and lower ischemic risk, compared with non-East Asians (nEAs). We sought to compare DAPT “de-escalation” strategies in EA and nEA populations. Methods A systematic review and meta-analysis of randomized controlled trials assessing reduction of DAPT intensity or duration in ACS patients undergoing percutaneous coronary intervention, in EA and nEA, was performed using a random-effects model. Results Twenty-three trials assessed reduction of DAPT intensity (n = 12) or duration (n = 11). Overall, reduced DAPT intensity attenuated major bleeding (odds ratio [OR]: 0.78, 95% confidence interval [CI]: 0.65–0.94, p = 0.009), without impacting net adverse cardiovascular events (NACE) or major adverse cardiovascular events (MACE). In nEA, this increased MACE (OR: 1.20, 95% CI: 1.09–1.31, p < 0.0001) without impacting NACE or bleeding; while in EA, it reduced major bleeding (OR: 0.71, 95% CI: 0.53–0.95, p = 0.02) without affecting NACE or MACE. Overall, abbreviation of DAPT duration reduced NACE (OR: 0.90, 95% CI: 0.82–0.99, p = 0.03) due to major bleeding (OR: 0.69, 95% CI: 0.53–0.99, p = 0.006), without impacting MACE. In nEA, this strategy did not impact NACE, MACE, or major bleeding; while in EA, it reduced major bleeding (OR: 0.60, 95% CI: 0.4–0.91, p = 0.02) without impacting NACE or MACE. Conclusion In EA, reduction of DAPT intensity or duration can minimize bleeding, without safety concerns. In nEA, reduction of DAPT intensity may incur an ischemic penalty, while DAPT abbreviation has no overall benefit.Peer reviewe