The use of NOACs with dual antiplatelet therapy (DAPT) presents a therapeutic dilemma. There is uncertainty over the optimal antithrombotic management strategy for patients with AF presenting with an acute coronary syndrome and/or undergoing percutaneous coronary intervention (PCI)/stenting.
Professor De Caterina showed that 8–10 % of AF patients of cardiology departments develop ACS or need elective stent implantation and 15–20 % of post ACS or electively stented patients develop AF and are therefore candidates for anticoagulation.
The use of DAPT in patients with AF after coronary stenting is essential to prevent stent thrombosis and is supported by a large body of clinical trial data; however, the use of OACs is needed to reduce the risk of stroke, and this therapeutic entity has been well-evaluated in many trials.When used together, these therapies confer a major bleeding risk. In a Danish cohort study using national registries to identify over 82,000 patients with AF during the period 1997 to 2006 taking post-hospital therapy of warfarin, aspirin, clopidogrel and combinations of these drugs, 11.4 % developed a nonfatal or fatal bleeding over a mean 3.3 years’ follow-up, with those on triple therapy having an incidence rate of 10–13 % per patient year.
It is therefore vital to establish an equilibrium between the risk of thrombosis (stent thrombosis and stroke) and the risk of bleeding. The ESC guidelines have stratified patients into low- and high-risk groups to minimise the time of overlap of drugs. The time of triple therapy should be as short as possible; a maximum of 1 month is recommended for the combined use of aspirin and clopidogrel, on the background of a vitamin K antagonist (VKA), with elective stenting with bare-metal stents (BMS). With drug-eluting stents (DES) in the setting of elective PCI, a maximum of 6 months and, for more recent stents, 3 months is suggested, then continuing with one single antiplatelet agent and the VKA. In the case of ACS a triple therapy overlap is advised for 6 months. The overlap should, however, be shorter in patients at high bleeding risk, in whom BMS are recommended anyhow, and in such cases the continuation of antithrombotic therapy with a VKA only is recommended after the first month. In case of patients at high bleeding risk having received stenting (usually BMS) because of an ACS, triple therapy is still restricted to 1 month, but continuing a VKA with the addition of one antiplatelet agent (clopidogrel or aspirin) up to 1 year (see Figure 3).
A consensus document of the AHA is more complex and was not discussed here. However, these guidelines only cover triple therapy involving VKAs; triple therapy involving NOACs is still under investigation.
This educational activity is intended for an international audience of non-US healthcare professionals, specifically electrophysiologists and cardiologists. However, neurologists, internal medicine specialists, primary care physicians, and other healthcare professionals involved in the diagnosis and management of patients with atrial fibrillation (AF) will also find this topical.
The Novel Oral Anti-Coagulants (NOACs): Hot Topics & Current Issues roundtable was supported by an unrestricted educational grant by Daiichi-Sankyo.
The assigned learning objectives for this roundtable are listed for your information: