Written By Katrina Mountfort, Medical Writer, Radcliffe Cardiology
Reviewers - John Camm, Marco Alings, Raffaele De Caterina, Paulus Kirchhof, Jean-Yves Le Heuzey, Freek W A Verheugt
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.36 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.36 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 NOACs 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.37 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).38 A consensus document of the AHA is more complex and was not discussed here.39 However, these guidelines only cover triple therapy involving VKAs; triple therapy involving NOACs is still under investigation.
Several trials are ongoing in patients with AF and ACS and/or coronary stents. The PIONEER trial (a study exploring two strategies of rivaroxaban – 15 mg once daily + clopidogrel; 2.5 mg twice daily + DAPT for the initial 1, 6 or 12 months – versus the ‘classic’ triple therapy with a VKA + aspirin + clopidogrel in patients with AF who undergo a PCI),40 will enrol 21,000 participants. The RE-DUAL-PCI (Evaluation of Dual Therapy With Dabigatran vs Triple Therapy With Warfarin in Patients With AF That Undergo a PCI With Stenting) trial will evaluate dabigatran (110 mg twice daily) + a single APT, dabigatran 150 mg twice daily + single APT and warfarin and DAPT.41 All these trials have limitations in that more than one component of the comparator ‘cocktail’ – a VKA + aspirin + clopidogrel – is being changed at a time, and the final interpretation of the data may prove difficult.
A panel discussion ensued about the need to use aspirin post-PCI. The panellists agreed that there was an excess co-prescription of these drugs and that it may be safe to use single APT with NOACs. Clopidogrel is preferred unless there is a definite stent thrombosis, according to Professor Kirchhof, in his institution, as newer agents have not been tested in patients who are anticoagulated. Patients in the RE-LY trial underwent stenting and, while bleeding rates increased, there was no difference in outcomes between warfarin and dabigatran. When performing interventions in anticoagulated patients presenting with ACS, every possible effort should be taken to prevent bleeding, e.g. a radial rather than femoral approach. The new bio-absorbable stents should minimise the need for long-term triple therapy. In conclusion, the addition of NOACs to APT may help prevent ischaemic events and stent thrombosis, but this needs testing in a clinical trial setting. It is important to balance the antithrombotic and anticoagulant effect of the different agents, but more clinical trial data are needed.
For a full written summary of discussions please click here:
A. John Camm, Professor of Clinical Cardiology and Head of the Department of Cardiac and Vascular Sciences, St. George's Hospital Medical Centre, London, UK
Marco Alings, Director of the Cardiology Training Program, Amphia Ziekenhuis, Breda, The Netherlands
Raffaele De Caterina, Professor of Cardiology and Director of the University Cardiology Division, "G. d'Annunzio" University, Chieti, Italy
Paulus Kirchhof, Chair in Cardiovascular Medicine Cardiovascular and Respiratory Sciences, University of Birmingham, UK
Jean-Yves Le Heuzey, Professor of Cardiology and Head of the Arrhythmia Department, Georges Pompidou Hospital, Paris, France
Freek Verheugt, Chairman, Department of Cardiology, Onze Lieve Vrouwe Gasthuis (OLVG), Amsterdam, The Netherlands
Professor Camm has disclosed the following financial relationships:
Consultant/Advisor/Speaker: Actelion, Astellas, AstraZeneca, Bayer, Boehringer Ingelheim, Boston Scientific, Biotronik, BMS, ChanRX, Daiichi Sankyo, Gilead, GSK, InfoBionic, Incarda, Johnson and Johnson, Medtronic, Menarini, Merck, Mitsubishi, Novartis, Otsuka, Pfizer, Sanofi, Servier, St. Jude Medical, Takeda, Xention
Doctor Alings has disclosed the following financial relationships:
Consultant/Advisor: Bayer, Boehringer Ingelheim, BMS/Pfizer, Daiichi Sankyo
Professor De Caterina has disclosed the following financial relationships:
Research grants: Boehringer Ingelheim
Consultant/Advisor/Speaker: Bayer, Boehringer Ingelheim, BMS/Pfizer, Daiichi Sankyo, Novartis
Professor Kirchhof has disclosed the following financial relationships:
Research grants: BMS/Pfizer, Cardiovascular Therapeutics, Daiichi Sankyo, Sanofi, St. Jude Medical.
Consultant/Advisor/Speaker: Bayer, Boehringer Ingelheim, BMS, Daiichi Sankyo, Johnson & Johnson, Medtronic, MSD, Pfizer, Servier
Professor Le Heuzey has disclosed the following financial relationships:
Consultant/Advisor: Bayer, Boehringer Ingelheim, BMS/Pfizer, Daiichi Sanyo
Professor Verheugt has disclosed the following financial relationships:
Consultant/Advisor: Bayer, Boehringer Ingelheim, BMS/Pfizer, Daiichi Sankyo
The assigned learning objectives for this roundtable are listed for your information:
- To review the established evidence-base for non-VKA thromboprophylaxis in atrial fibrillation (AF)
- To consider recent and emerging data on non-VKA oral anticoagulants in AF trials and registries
- To discuss on-going non-VKA oral anticoagulant research in patients with AF
- To identify and refine the indications for specific non-VKA oral anticoagulants in AF
- To establish the nature of further non-VKA oral anticoagulant research needed for new AF indications
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.
This course is accredited by the European Board for Accreditation in Cardiology (EBAC) for 1 CME credit hour. The CME e-learning modules can be accessed here.
The CME element of this educational module has been managed by Siyemi Learning and is powered by CME-CPD Academy.
The Novel Oral Anti-Coagulants (NOACs): Hot Topics & Current Issues roundtable was supported by an unrestricted educational grant by Daiichi-Sankyo.