Prediction of the Individual Risk of Bleeding in Patients with Atrial Fibrillation Undergoing Percutaneous Coronary Intervention

Abstract

To the editor, The antithrombotic management of patients presenting with atrial fibrillation (AF) who experience acute coronary syndrome (ACS) or have undergone percutaneous coronary intervention (PCI) with stent implantation remains a major challenge in daily clinical practice. Facing the dilemma that dual anti-platelet therapy (DAPT) is superior to oral anticoagulation (OAC) in terms of avoiding stent thrombosis, but inferior to OAC in the prevention of stroke and systemic embolism, the combination of DAPT and an OAC agent—via direct oral anticoagulants (DOAC) or vitamin-K antagonists (VKA)—as triple antithrombotic therapy (TAT) mirrors a guideline-supported practice in those individuals [1]. However, while TAT is associated with a lower burden of both stent thrombosis and thromboembolic events, this aggressive pharmacotherapeutic approach accompanies a nearly fourfold increased risk for major bleeding events and furthermore doubles the risk of intracranial bleeding as compared to sole OAC without concomitant anti-platelet therapy [2, 3]. Meanwhile, the large randomized controlled clinical trials WOEST (What is the Optimal antiplatElet & Anticoagulant Therapy in Patients With Oral Anticoagulation and Coronary StenTing), PIONEER AF-PCI (An Open-label, Randomized, Controlled, Multicenter Study Exploring Two Treatment Strategies of Rivaroxaban and a Dose-Adjusted Oral Vitamin K Antagonist Treatment Strategy in Subjects With Atrial Fibrillation Who Undergo Percutaneous Coronary Intervention), RE-DUAL PCI (Evaluation of Dual Therapy With Dabigatran vs. Triple Therapy With Warfarin in Patients With AF That Undergo a PCI With Stenting), and AUGUSTUS (An Open-label, 2 x 2 Factorial, Randomized Controlled, Clinical Trial to Evaluate the Safety of Apixaban vs. Vitamin K Antagonist and Aspirin vs. Aspirin Placebo in PatientsWith Atrial Fibrillation and Acute Coronary Syndrome or Percutaneous Coronary Intervention) compared the efficacy and safety of a dual antithrombotic therapy (DAT)—the combination of OAC with only one anti-platelet agent—versus TAT inAF patients with ACS or undergoing PCI. Among these studies, a significantly lower bleeding event rate was observed within DAT regimen compared to TAT. Despite that, it needs to be considered that a significant fraction of major bleeding events in the respective randomized trials occurred within the first weeks after initiation of TAT [4–7]. Subsequently, an administration of DAT appears to be most beneficial if started at an early stage of patient care after PCI or ACS. As suggested by the currently available guidelines of the European Society of Cardiology (ESC), it remains of utmost importance to carefully select patients that are eligible for DAT instead of TAT by weighing their bleeding risk against their individual risk of stent thrombosis. Factors associated with high-risk PCI or increased risk of stent thrombosis—e.g., stenting of the left main, bifurcation intervention, stent malapposition, multiple stent implantation, or stents with small diameter— deserve in-depth attention to assess the individual ischemic risk. Similarly, clinical characteristics that proved to be associated with an elevated risk of ischemia (e.g., patients presenting with ACS or diabetes mellitus) need to be considered. In this regard, Alkhalil and co-workers recently demonstrated a significantly higher risk of ischemic events in patients with complex PCI when discharged with DAT. The authors conclude that the procedural complexity in patients with an indication for OAC that underwent stent implantation should be taken into account and that the omission of aspirin in patients with high-risk PCI should be discouraged [8]. However, to achieve a favorable net clinical benefit in the respective patient population, a reduced duration of TAT is most likely reasonable in individuals presenting with an elevated risk of bleeding. Therefore, the personalized evaluation of the individual risk of bleeding via standardized and * Patrick Sulzgruber [email protected]