One month of clot prevention after a stent was as effective as year-long course for AFib

Research Highlights:

• A one-month course of dual clot-preventing therapy followed by a single clot-prevention medication for the remainder of the standard 12-month regimen in adults with atrial fibrillation (AFib) who received a coronary stent was as effective as one year of continuous dual therapy for preventing stroke, heart attack and death.
• Participants treated with the one-month regimen experienced fewer bleeding problems than those in the year-long dual-treatment group.
• This is the first study to suggest the one-month strategy is as safe and effective as the standard year-long regimen of dual clot-preventing therapy for people with AFib treated with a stent.
• Note: The study featured in this news release is a research abstract. Abstracts presented at American Heart Association's scientific meetings are not peer-reviewed, and the findings are considered preliminary until published as a full manuscript in a peer-reviewed scientific journal.

Embargoed until 1:45 p.m., CT/2:45 p.m. ET, Saturday, Nov. 8, 2025

NEW ORLEANS, Nov. 8, 2025 - New research found a simplified clot-preventing medication regimen following stent placement in adults with atrial fibrillation was just as safe and effective in preventing strokes, heart attack and death, when compared to a standard year-long treatment regimen, according to a preliminary late-breaking science presentation today at the American Heart Association's Scientific Sessions 2025.

The meeting, Nov. 7-10, in New Orleans, is a premier global exchange of the latest scientific advancements, research and evidence-based clinical practice updates in cardiovascular science.

This study included adults with atrial fibrillation (AFib), a common heart rhythm disorder, who received a stent in a heart artery to improve blood flow. Standard treatment after a stent implantation is a prescription for two clot-preventing medications for one year, however, these medications can also increase the risk of serious bleeding, explained study author Yohei Sotomi, M.D., Ph.D., director of the Osaka Cardiovascular Conference Multicenter Clinical Research Lab in the Department of Cardiovascular Medicine at University of Osaka Graduate School of Medicine in Osaka, Japan. The two medications included a direct oral anticoagulant, such as dabigatran, rivaroxaban, apixaban and edoxaban to help prevent strokes; and a P2Y12 inhibitor, such as clopidogrel or prasugrel, to prevent clots in the stent.

In this study, the OPTIMA-AF trial, researchers explored if using both medications for one month among people with AFib who received a stent would be equally safe and effective as 12 months of treatment, while helping to reduce bleeding risk associated with the medications.

"Previous studies confirmed that using two anti-clotting agents instead of three reduced bleeding, however, no study has tested whether the duration of dual therapy could be safely shortened to just one month," Sotomi said. "Our study is the first to show that a one-month strategy is both safe and effective, offering real-world benefits for patients and doctors."

Researchers studied more than 1,000 adults in Japan who had AFib and received a stent in a heart artery. After the stent placement procedure, half of the study participants were prescribed both types of medications for one month, then only the direct oral anticoagulant for the remaining 11 months. The other half of participants continued dual therapy for 12 months.

Participants were followed for one year to monitor if they had a stroke, heart attack or died. Researchers also analyzed how many participants had bleeding complications such as gastrointestinal bleeding.

The analysis found:

• 5.4% of participants in the one-month group and 4.5% in the 12-month group had a heart attack, stroke or died, which researchers said suggests the shorter approach was equally effective.
• Participants in the one-month dual-treatment group had notably fewer bleeding complications: 4.8% versus 9.5% in the 12-month group.
• Most of the bleeding reduction came from less serious bleeds that required medical attention, which affects quality of life and can increase health care costs for emergency or clinic visits, lab and imaging tests.

"These results may help doctors feel more confident in prescribing shorter durations of dual antithrombotic therapy after stenting among some patients with AFib," Sotomi said. "By reducing the length of time individuals are exposed to combination therapy, we can lower the risk of bleeding - a serious concern for many older adults-without increasing their risk of stroke or heart attack."

Up to one in 10 people who receive a stent also have AFib, a disorder that increases stroke risk by five-fold and can lead to blood clots, heart failure and death, Sotomi said. According to the American Heart Association 2025 Heart and Stroke statistics, an estimated five million adults in the U.S. have AFib, and it is predicted that more than 12 million people in the U.S. will have it by 2030.

The study was conducted in Japan, so its findings may not directly apply to people in other countries. Another limitation is that study participants mostly had stable heart disease, so results may not apply to patients with higher risk for blood clots. In addition, only about 20% of the study population were women, so generalizability to women is limited.

Study details, background and design:

• The study included 1,101 adults with an average age of 75.2 years old; 79% were men; and all had atrial fibrillation and underwent a procedure to implant a drug-eluting stent.
• The study enrolled participants with AFib who received stents at 75 hospitals in Japan between October 2019 and September 2024.
• Researchers collected data on rates of death, stroke, heart attack, clotting in stents and bleeding events.
• The trial compared one-month versus 12-month dual antithrombotic therapy with a direct oral anticoagulant and a P2Y12 inhibitor, followed by the oral anticoagulant alone, with outcomes assessed at 12 months.
• Participants and researchers knew which regimen each participant received; however, assignment to the regimens was by chance.

Co-authors, their disclosures and funding information is listed in the abstract.

Statements and conclusions of studies that are presented at the American Heart Association's scientific meetings are solely those of the study authors and do not necessarily reflect the Association's policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. Abstracts presented at the Association's scientific meetings are not peer-reviewed, rather, they are curated by independent review panels and are considered based on the potential to add to the diversity of scientific issues and views discussed at the meeting. The findings are considered preliminary until published as a full manuscript in a peer-reviewed scientific journal.

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Additional Resources:

• Multimedia is available on the right column of the release link.
• View the abstract in the American Heart Association Scientific Sessions 2025 Online Program Planner
• American Heart Association health information: Learn about AFib and your heart (Video)
• Watch an animation of atrial fibrillation.
• American Heart Association health information: What Is a Coronary Artery Stent?
• American Heart Association patient support network: MyAFibExperience®
• American Heart Association guidelines: 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines
• About Scientific Sessions 2025
• For more news at AHA Scientific Sessions 2025, follow us on X @HeartNews,#AHA25

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