Medical News 

March 28, 2025

7 Takeaways for Primary Care Clinicians From the Updated Acute Coronary Syndromes Guideline

Linda Rodgers

JAMA. 2025;333(16):1375-1376. doi:10.1001/jama.2025.2931

The American College of Cardiology (ACC) and the American Heart Association (AHA) have published a new guideline for managing patients with acute coronary syndromes (ACS), the first update since 3 related guidelines were released from 2013 to 2015. That decade-plus-long gap was a big motivator, said Sunil Rao, MD, the director of interventional cardiology at NYU Langone Health and chair of the guideline writing committee.

“There have been multiple randomized trials that have examined all aspects of acute coronary syndrome care that really served as the platform for updating the ACS guidelines,” he explained. “I think clinicians needed to understand which of these trials fit into the different ways that these acute coronary syndrome patients need to be treated.”

About 1.2 million people in the US are hospitalized with ACS every year, according to the ACC. As noted in the guideline, ACS represents 3 conditions that can occur when a blood clot originating from an unstable cholesterol plaque slows or completely blocks blood flowing to the heart. The conditions include unstable angina and 2 types of myocardial infarctions. The first is non–ST-segment elevation myocardial infarction (NSTEMI), a heart attack—caused by incomplete arterial blockage—that can’t be detected by an electrocardiogram (ECG). The other is the more severe STEMI, a heart attack—caused by complete blockage—that can be detected by both blood work and an ECG.

All 3 require emergency care, and many of the new recommendations are focused on the acute care phase of ACS. One involves procedural aspects of patients with STEMI undergoing cardiac catheterization and stenting. In the past, clinicians used either coronary artery bypass graft surgery or percutaneous coronary intervention (PCI) to open the blocked artery. But there weren’t strong recommendations for opening up other arteries that showed signs of blockage but hadn’t led to the heart attack, Rao said. Because multiple trials have shown that using PCI on these other arteries is associated with better outcomes, the new guideline notes this as a class 1 recommendation for patients with hemodynamically stable STEMI, he explained.

Another new class 1 recommendation involves conducting PCI via the radial, or wrist, artery instead of the artery in the groin to minimize bleeding and complications. “This was something that wasn’t even mentioned in the previous guidelines,” Rao noted.

Complications after ACS can also be chronic, requiring preventive care to avoid another event, Rao said.

That’s why the guidelines are important for primary care and internal medicine clinicians, said Rohan Khera, MD, MS, a cardiologist and director of the cardiovascular data science laboratory at Yale University. The new guidelines “go beyond just the cardiovascular community to include those who will use these guidelines as the benchmark for how they deliver care,” added Khera, who is also an associate editor of JAMA and was not involved with the new recommendations.

Rao and Khera shared several takeaways that are relevant to primary care clinicians.

Not All Antiplatelet Drugs Act the Same Way

“We have trained ourselves to believe as primary care clinicians that all antiplatelet medications are similar, especially for those we use after a stent is placed, say, for a heart attack,” Khera said. But because the antiplatelet drugs ticagrelor and prasugrel have been shown to act more quickly in patients than clopidogrel, the updated guideline recommends using them over clopidogrel. That’s important, Khera said, because clopidogrel had been used more frequently first because of its lower cost.

Dual Antiplatelet Therapy Depends on a Patient’s Bleeding Risk

Twelve months of an antiplatelet medication plus aspirin has been the standard of care for patients with ACS after a PCI—a legacy recommendation that carried over into the updated guidelines, Rao said. And although this is still the default, the guideline now recommends different drugs if a patient is at a higher risk of bleeding, he explained.

Because there have been multiple randomized trials that have focused on people who have a high bleeding risk—a population that Rao noted includes much older adults or those with kidney failure—“it’s beneficial to deescalate that dual antiplatelet therapy using a variety of strategies to maintain the ischemic benefit and try and reduce that bleeding risk,” he said.

These include using a gastrointestinal-protective proton pump inhibitor or dropping the aspirin altogether and using a less powerful anticoagulant like clopidogrel.

Place More Emphasis on Aggressive LDL-Lowering Strategies

Pushing low-density lipoprotein (LDL) cholesterol levels lower is associated with an improvement in outcomes and a reduction in subsequent ischemic events, Rao said. That’s why the updated guidelines now advise LDL levels to drop below 70 mg/dL. In fact, 55 mg/dL is a potential goal, according to Rao, although stronger data are needed around that number. Still, “the lower the LDL, the better,” he added.

That’s why patients with ACS should be taking high-intensity statins, defined as 40 mg to 80 mg of atorvastatin or 20 mg to 40 mg of rosuvastatin. If patients are already at high-intensity doses or at the highest dose they can tolerate, then clinicians can add a nonstatin such as ezetimibe to lower LDL levels to less than 70 mg/dL. Adding nonstatins to the regimen isn’t done enough in the primary care setting, which is problematic, Khera noted.

And because there are now more nonstatin therapies, if one drug doesn’t work, “we have to try a different one,” Rao said. The bottom line is that it’s important to get to the target LDL cholesterol level because the long-term durable risk reduction is so clear, he added.

Make a Stronger Push for Cardiac Rehabilitation

Cardiac rehabilitation is now a class 1 recommendation for all patients with ACS. In fact, the 2025 guideline suggests patients should be referred to outpatient cardiac rehabilitation before they’re discharged from the hospital.

The benefits are clear. People who attend the recommended 36-session course can cut their risk of overall death and subsequent heart attacks by 47% and 31%, respectively, according to Million Hearts, the initiative co-led by the Centers for Disease Control and Prevention (CDC) and the Centers for Medicare & Medicaid Services. It can reduce hospitalizations while improving quality of life and functional status too, the updated guideline stated.

The problem is that too few people take advantage of cardiac rehabilitation—national statistics from the CDC suggest participation is anywhere from 19% to 34%. It’s even less for women and members of disadvantaged minority groups, Million Hearts has found.

One of the challenges is that there aren’t a lot of facilities, Rao noted. And while better data are needed, the 2025 guideline makes a 2a (or moderately strong) recommendation for home-based cardiac rehabilitation programs, especially for patients who can’t access outpatient facilities.

It’s important for primary care clinicians to be aware of these home-based rehabilitation programs, so they can share and discuss them with patients and their cardiologists, Khera suggested.

Low-Dose Colchicine May Help Some Patients with ACS.

Colchicine, an anti-inflammatory, is the standard treatment for gout. And it’s “had a lot of excitement around it,” said Rao, based on a few randomized trials that found it lowered the risk of heart attacks in patients with coronary artery disease, including ACS.

But the evidence on its efficacy is mixed. A large randomized trial last year showed no benefit. So the updated guideline gave a class 2b (or weak) recommendation to a daily dose of colchicine at 0.5 to 0.6 mg.

“A low dose of colchicine may be considered for patients after ACS to reduce the risk of [a major adverse cardiovascular event] because the data are a little bit conflicting,” Rao said. Plus, it may be hard to tolerate in some patients because of the gastrointestinal adverse effects, he added.

A Yearly Flu Shot Is Important

Influenza vaccines have reduced the risk of death and major adverse cardiac events, according to the 2025 guideline. So primary care and internal medicine clinicians should take note that a yearly flu shot is a class 1 recommendation for patients with ACS, Rao said.

There’s Room for Clinician Judgment

Rao emphasized that the guidelines went through a rigorous peer review, but that they can’t be all things to all people. “Clinicians need to exercise their clinical judgment in application of these guidelines at the bedside.”