Stopping DAPT after one-month improved outcomes in stent patients

March 18, 2019

Patients who stopped taking aspirin one month after receiving a stent in the heart's arteries but continued taking the P2Y12 inhibitor clopidogrel fared significantly better after one year compared with those who followed the standard practice of continuing both medications, according to research presented at the American College of Cardiology's 68th Annual Scientific Session. Stopping aspirin early was found to be superior in terms of the trial's primary endpoint, a composite of death from cardiovascular causes, heart attack, clotting near the stent, stroke and major bleeding.

The trial sheds new light on the optimal way to balance the risk of clotting and bleeding in patients who undergo procedures to clear blocked arteries. Giving these patients antiplatelet medications that reduce the body's ability to clot blood can reduce the chance of clot-related problems such as heart attacks and stroke, but these medications can also lead to uncontrolled bleeding.

The newest generation of stents--mesh tubes used to prop an artery open--release drugs that prevent new blockages from forming around the stent. While current guidelines recommend patients take aspirin and a P2Y12 inhibitor such as clopidogrel for at least 12 months after receiving a stent, a strategy known as dual antiplatelet therapy (DAPT), doctors have sought to determine whether this is the best combination of drugs to use with newer drug-eluting stents. The new trial assessed whether stopping aspirin after one month but continuing clopidogrel alone for 12 months might be a better approach.

"Standard 12-month DAPT is currently recommended by the guidelines, and one-month DAPT has not yet been implemented in daily clinical practice," said Hirotoshi Watanabe, MD, research associate at Kyoto University Graduate School of Medicine and the study's lead author. "According to our findings, one-month DAPT followed by clopidogrel monotherapy could be a good option after drug-eluting stent implantation with an advantage of fewer bleeding events."

The trial, known as STOPDAPT-2, enrolled 3,009 patients who received a drug-eluting stent at 89 medical centers in Japan. Patients who were taking oral anticoagulants, could not tolerate clopidogrel or had a history of bleeding in the brain were excluded. Half of the patients were randomly assigned to receive standard DAPT. The other half took aspirin plus clopidogrel or prasugrel (another P2Y12 inhibitor) for the first month and took clopidogrel only after that, with patients who took prasugrel initially switching to clopidogrel after the first month.

In the one-month DAPT group, aspirin was stopped at one month in 96 percent of patients, while DAPT was continued up to one year in 88 percent of patients in the standard 12-month DAPT group. Overall, stopping aspirin after one month reduced the risk of adverse events by 36 percent. After one year, 2.4 percent of patients who stopped aspirin after one month experienced the composite primary endpoint compared to 3.7 percent among those following standard DAPT.

An analysis of secondary endpoints revealed stopping aspirin after one month significantly reduced the rate of bleeding. Overall, 0.4 percent of those stopping aspirin experienced major bleeding compared to 1.5 percent among those following standard DAPT. Furthermore, stopping aspirin after one month did not increase the events related to clotting, known as ischemic events, in a secondary endpoint that included a composite of death from cardiovascular causes, heart attack, clotting around the stent or stroke.

"One-month DAPT followed by clopidogrel monotherapy as compared with standard 12-month DAPT reduced the bleeding events and did not increase the ischemic events," Watanabe said. "That lead to a net clinical benefit for both ischemic and bleeding outcomes."

One limitation of the study is that most of the participants were at low or intermediate risk for ischemic events. Watanabe said it is unknown whether the study can be extrapolated to apply in higher-risk patients. To answer this question, the researchers are continuing to enroll patients in the trial who have acute coronary syndrome, a group that is at higher risk for ischemic events.

The study was also open-label, meaning that patients knew which drugs they had been assigned to take. After 12 months, the patients who stopped aspirin were instructed to continue taking clopidogrel, while the patients in the DAPT arm were instructed to discontinue clopidogrel but continue taking aspirin. The researchers plan to continue to track outcomes until five years after patients received their stent.
The study received funding from Abbott Vascular Japan, Co., Ltd.

The ACC's Annual Scientific Session will take place March 16-18, 2019, in New Orleans, bringing together cardiologists and cardiovascular specialists from around the world to share the newest discoveries in treatment and prevention. Follow @ACCinTouch, @ACCMediaCenter and #ACC19 for the latest news from the meeting.

The American College of Cardiology envisions a world where innovation and knowledge optimize cardiovascular care and outcomes. As the professional home for the entire cardiovascular care team, the mission of the College and its more than 52,000 members is to transform cardiovascular care and to improve heart health. The ACC bestows credentials upon cardiovascular professionals who meet stringent qualifications and leads in the formation of health policy, standards and guidelines. The College also provides professional medical education, disseminates cardiovascular research through its world-renowned JACC Journals, operates national registries to measure and improve care, and offers cardiovascular accreditation to hospitals and institutions. For more, visit

American College of Cardiology

Related Heart Attack Articles from Brightsurf:

Top Science Tip Sheet on heart failure, heart muscle cells, heart attack and atrial fibrillation results
Newly discovered pathway may have potential for treating heart failure - New research model helps predict heart muscle cells' impact on heart function after injury - New mass spectrometry approach generates libraries of glycans in human heart tissue - Understanding heart damage after heart attack and treatment may provide clues for prevention - Understanding atrial fibrillation's effects on heart cells may help find treatments - New research may lead to therapy for heart failure caused by ICI cancer medication

Molecular imaging identifies link between heart and kidney inflammation after heart attack
Whole body positron emission tomography (PET) has, for the first time, illustrated the existence of inter-organ communication between the heart and kidneys via the immune system following acute myocardial infarction.

Muscle protein abundant in the heart plays key role in blood clotting during heart attack
A prevalent heart protein known as cardiac myosin, which is released into the body when a person suffers a heart attack, can cause blood to thicken or clot--worsening damage to heart tissue, a new study shows.

New target identified for repairing the heart after heart attack
An immune cell is shown for the first time to be involved in creating the scar that repairs the heart after damage.

Heart cells respond to heart attack and increase the chance of survival
The heart of humans and mice does not completely recover after a heart attack.

A simple method to improve heart-attack repair using stem cell-derived heart muscle cells
The heart cannot regenerate muscle after a heart attack, and this can lead to lethal heart failure.

Mount Sinai discovers placental stem cells that can regenerate heart after heart attack
Study identifies new stem cell type that can significantly improve cardiac function.

Fixing a broken heart: Exploring new ways to heal damage after a heart attack
The days immediately following a heart attack are critical for survivors' longevity and long-term healing of tissue.

Heart patch could limit muscle damage in heart attack aftermath
Guided by computer simulations, an international team of researchers has developed an adhesive patch that can provide support for damaged heart tissue, potentially reducing the stretching of heart muscle that's common after a heart attack.

How the heart sends an SOS signal to bone marrow cells after a heart attack
Exosomes are key to the SOS signal that the heart muscle sends out after a heart attack.

Read More: Heart Attack News and Heart Attack Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to