Field in Flux: What’s the Best Antithrombotic Strategy for A-fib Patients Undergoing PCI?

A new state-of-the-art consensus statement from a group of American and European experts highlights the currently recommended antithrombotic treatment strategies for patients with atrial fibrillation undergoing PCI for coronary artery disease, but also points to the way two groups can sift through the same evidence and have differing opinions in this difficult-to-treat patient population.

For example, while both the European and US guidelines recommend oral anticoagulation and use of a P2Y12 inhibitor following PCI, there are subtle differences on the two sides of the Atlantic Ocean with respect to how long aspirin should be included as part of the triple antithrombotic treatment regimen.

“The biggest difference is the duration of triple therapy and, let’s say, what is the default approach to treatment,” lead author Davide Capodanno, MD, PhD (University of Catania, Italy), told TCTMD. “In Europe, the default approach in 2019 is triple therapy with doctors invited to look for candidates who are eligible for dual antithrombotic therapy. In North America, it’s the other way around. The default approach is dual therapy and physicians are encouraged to look for candidates for triple therapy. It’s another mind-set.”

Two consensus statements representing the European and North American approaches to antithrombotic therapy were published in 2018, and these offer practical directions regarding the specific treatment of patients with atrial fibrillation undergoing PCI. Both recommend use of a direct oral anticoagulant (DOAC) over a vitamin K antagonist and treatment with a P2Y12 inhibitor (clopidogrel preferred) for 12 months following PCI. However, the North American guidelines recommend physicians stop aspirin following the periprocedural period, while the European perspective is continued aspirin use for at least 1 month and a maximum of 6 months.   

Dominick Angiolillo, MD, PhD (University of Florida College of Medicine – Jacksonville), the senior author of the new paper, which was published online ahead of the July 9, 2019, issue of the Journal of the American College of Cardiology, also highlighted the differing North American and European approaches for how to best manage these patients.

“It’s a field where the US and European recommendations largely differ in contrast to other clinical recommendations, such as the duration of DAPT [dual antiplatelet therapy] after PCI [in patients without atrial fibrillation], which are aligned,” Angiolillo told TCTMD. “When it comes to this specific topic, there are significant differences. Also, the paper is a way to highlight that, with the same data, there are differences in opinions, but hopefully with the availability of some more recent data the two sides of the Atlantic will become more closely aligned.”

Evolving Field as New Evidence Emerges

Like Capodanno, Angiolillo said the two sides largely disagree on the duration of aspirin use. The North American perspective suggests dropping aspirin as soon as possible, an approach that reflects how the most recent clinical trials in this field have been performed, said Angiolillo. The European recommendations are a “bit more conservative,” he added, “and recommend keeping patients on aspirin longer than what was done in some of the most recent trials.”

The European and North American strategies do share similarities, particularly in their recommended use of DOACs over vitamin K antagonists at a dose established for stroke prevention and newer-generation DES for PCI.

Angiolillo pointed out that the 2018 consensus statements, as well the latest European Society of Cardiology guidelines for myocardial revascularization and the American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines for atrial fibrillation, were published before the results of the AUGUSTUS trial were known. In that trial, which was reported by TCTMD, dual antithrombotic therapy with clopidogrel and apixaban (Eliquis; Bristol-Myers Squibb) resulted in less bleeding and fewer hospitalizations without any significant difference in the risk of ischemic events when compared with regimens that included a vitamin K antagonist, aspirin, or both.

“This is a dynamic topic because from time to time it will change based on new evidence published in the field,” added Capodanno. “It’s quite interesting to see that many consensus documents have been published over time, and that the consensus document can be become obsolete when new trials are published. We felt that after the AUGUSTUS trial was published it was useful to revisit the topic—it was the largest trial published in this field—and it was a good time to reflect with the many experts on where treatment is moving.”

Capodanno pointed to a recent meta-analysis of the four major trials studying antithrombotic therapy in patients with atrial fibrillation undergoing PCI. Those studies—WOEST, PIONEER AF-PCI, RE-DUAL PCI, and AUGUSTUS—include more than 10,000 patients and showed that a strategy of a DOAC plus a P2Y12 inhibitor was associated with less bleeding—without a significant difference in the risk of major adverse cardiovascular events—compared with a strategy that combined DAPT plus a vitamin K antagonist. Based on those findings, the group, led by Renato Lopes, MD (Duke Clinical Research Institute, Durham, NC), concluded that a DOAC plus a P2Y12 inhibitor should be the preferred treatment strategy in this setting.

Capodanno, however, said the prospect of triple antithrombotic therapy is still relevant in selected patients but that he expects the field will continue to evolve.

Balancing Risk and Benefit

More data are expected shortly as physicians await the results of the ENTRUST-AF PCI trial, which is scheduled for presentation at the upcoming European Society of Cardiology 2019 Congress in Paris, France. In the study, 1,500 patients with atrial fibrillation who underwent successful PCI will receive a P2Y12 inhibitor for 12 months and be randomized to edoxaban (Savaysa; Daiichi Sankyo) or triple therapy with a vitamin K antagonist plus aspirin for a period of 1 to 12 months at the discretion of the treating physician.

The latest paper notes that both the European and North American recommendations provide physicians with some latitude in terms of altering treatment depending on the risk of bleeding versus the risk of thrombotic events and lists several high-risk features that may tip the balance toward more or less intense antithrombotic therapy. To TCTMD, Angiolillo said there is a need for further study to identify patients who might benefit from stopping aspirin immediately versus those who may benefit from continued aspirin use with a P2Y12 inhibitor and oral anticoagulation.

“This is a work in progress,” he said. “We felt that it was a good opportunity to understand the current status in how opinions from the two sides of the Atlantic are similar and different and use this as a stepping stone moving forward to fine-tune our recommendations in the future.”