Shortening the duration of dual antiplatelet therapy (DAPT) and continuing with a P2Y12 inhibitor alone after percutaneous coronary intervention (PCI) was associated with a similar rate of ischemic events but with less bleeding than prolonged DAPT at 3 years of follow-up in the SMART -CHOICE Trial.
“The current extended follow-up results from the SMART CHOICE study support evidence of an aspirin cessation strategy with indefinite use of the P2Y12 inhibitor after minimal use of DAPT in patients who have undergone PCI,” the researchers said together with lead author Ki Hong Choi. MD, Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
The 3-year results of the study were published online September 28 in JAMA Cardiology.
The authors state that while dual therapy with aspirin and a P2Y12 inhibitor after PCI with a drug-eluting stent is crucial to reduce the risk of ischemic events, it raises concerns about an increased risk of bleeding and the currently changing antiplatelet strategy after PCI the duration of DAPT.
Several recent randomized trials have consistently demonstrated that short-duration DAPT (1 to 3 months) followed by P2Y12 inhibitor monotherapy had protective ischemia effects comparable to those of longer-duration DAPT, and with a significantly reduced risk of bleeding events in patients who have undergone PCI, they note. However, these studies have so far only reported 1-year results, and long-term results are not yet available.
The SMART CHOICE study compared two antiplatelet strategies—3 months DAPT followed by long-term P2Y12 inhibitor monotherapy (primarily with clopidogrel) or prolonged DAPT for 12 months or more—in 2,993 patients undergoing PCI with a drug-eluting drug had undergone stenting. Results at 12 months showed a similar rate of ischemic events for both strategies, but a lower bleeding rate in the group that received a shortened DAPT.
SMART CHOICE investigators are now reporting the 3-year results, which show similar results.
At 3 years, the primary endpoint, a composite of death from any cause, myocardial infarction (MI), or stroke, had occurred in 6.3% of the shortened DAPT group and 6.1% of the lengthened DAPT group, resulting in a hazard ratio of 1, 06 yields (95% CI, 0.79 – 1.44).
But in the shortened DAPT group, the risk of bleeding was reduced. Bleeding Academic Research Consortium (BARC) type 2-5 bleeds occurred in 3.2% of the shortened DAPT group and 8.2% of the long DAPT group (HR 0.39; 95% CI 0.28-0, 55). Major bleeding, BARC types 3-5, occurred in 1.2% of the shortened DAPT group and 2.4% of the long DAPT group (HR: 0.56; 95% CI: 0.31-0 .99).
The landmark analyzes between 3 months and 3 years and per-protocol analyzes showed consistent results.
The investigators note that this is the first study to report the long-term safety and efficacy of P2Y12 inhibitor monotherapy as long-term maintenance therapy in stable patients treated with PCI.
“Especially considering that prolonged DAPT has significantly reduced the risk of ischemic events compared to aspirin monotherapy in some studies, a comparison between P2Y12 inhibitor monotherapy and prolonged DAPT for recurrent ischemic events over a longer period of time significant for more than a year,” they say.
They cite two other studies – HOST-EXAM and GLOBAL LEADERS – which have shown that P2Y12 inhibitor monotherapy is superior to aspirin monotherapy for preventing both ischemic and bleeding events during the long-term maintenance phase after PCI.
“By combining the results of the current study, the HOST-EXAM study, and the landmark analysis of the GLOBAL LEADERS study, after a minimum duration of DAPT, long-term P2Y12 inhibitor monotherapy could be the most reliable option among aspirin monotherapy, P2Y12 monotherapy, and its extended DAPT for maintenance therapy after stabilization of patients who have undergone PCI with a current-generation DES,” they conclude.
They point out that the American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions guidelines for coronary artery revascularization now recommend a shorter course of DAPT followed by P2Y12 monotherapy as a Class IIa indication. The recommendation is based on the results of five large, randomized clinical trials, including SMART-CHOICE, TWILIGHT, STOPDAPT-2, TICO and GLOBAL LEADERS.
“The current results of the extended follow-up from the SMART CHOICE study support evidence of an aspirin cessation strategy with indefinite use of the P2Y12 inhibitor after minimal use of DAPT in patients who have undergone PCI,” they say.
They point out that two additional studies, A-CLOSE in high-risk patients and SMART-CHOICE III, will be helpful in confirming these results.
P2Y12 Inhibitor Monotherapy “Attractive Concept”
In an accompanying editor’s note, Ajay Kirtane, MD, Columbia University Irving Medical Center/New York-Presbyterian Hospital, New York, and Roxana Mehran, MD, Icahn School of Medicine at Mount Sinai and the Cardiovascular Research Foundation, New York, note this Current guidelines recommend 3 to 6 months of DAPT after PCI with current-generation drug-eluting stents in stable patients and 6 to 12 months or longer in patients with acute coronary syndromes. In patients with an increased risk of bleeding, shorter DAPT durations can also be considered in individual cases.
Historically, the P2Y12 inhibitor (clopidogrel, prasugrel, or ticagrelor) was the component of DAPT that was the subject of discontinuation decisions, but recent studies have further evaluated whether discontinuation of the aspirin component of DAPT reduces bleeding while preserving antiischemic efficacy can.
The editors state that the concept of P2Y12 inhibitor monotherapy is attractive because it can optimize anticoagulant effects from a single agent, which can avoid the gastrointestinal toxicity of aspirin and the increased bleeding associated with the combination of multiple antithrombotic agents.
They suggest that the long-term results of the SMART CHOICE study “should prompt clinicians to consider a strategy of monotherapy after a short duration of DAPT as feasible to reduce the risk of bleeding,” although they also note that SMART CHOICE this was too weak to rigorously assess ischemic differences, so caution is advised.
“For patients at greatest risk for recurrent ischemic events, the role of continued DAPT is always an option, but these data (and other consistent studies) give clinicians more power to make individualized treatment decisions,” they write.
“For some, the ever-changing field of post-PCI antiplatelet aggregation has presented too many opportunities, which can be dizzying at times. For us, every patient is different, and careful evidence-based weighing is increasingly possible for many of our treatment decisions,” they conclude.
The SMART CHOICE study was supported by unrestricted grants from the Korean Society of Interventional Cardiology, Abbott Vascular, Biotronik and Boston Scientific.
JAMA Cardiol. Published online September 28th. Summary, editor’s note
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