By Cyra-Lea Drummond, BSN, RN Published on June 23, 2023 Fact checked by Nick Blackmer
Key Takeaways
- Beta-blockers are a tried-and-true class of medications prescribed to patients who have experienced a heart attack or have heart failure.
- New research shows that long-term beta-blocker use may not improve outcomes in certain patients, particularly those whose heart function is only mildly reduced.
- Individuals who have experienced a heart attack should take their medications as prescribed and see their cardiologist regularly to evaluate their treatment plan.
Beta-blockers are a long-standing treatment for patients after a heart attack because they protect the heart from further damage. They also promote heart function for those with cardiac dysfunction, or heart failure. But three new studies published in close succession show that long-term beta-blocker use may not benefit some patients as much as once thought.
Though researchers have identified some pitfalls of long-term beta-blocker use, experts say these drugs will still be prescribed and are useful to many patients. But there are several other heart disease treatments they want people to know about, too.
What Are Beta-Blockers and Why Are They Prescribed?
If you’ve ever ridden a rollercoaster or been frightened by someone sneaking up behind you, you’ve likely experienced the effects of adrenaline, the body’s “fight or flight” hormone. Adrenaline, also known as epinephrine, is a catecholamine, a class of hormones the nervous system makes in response to stress.
Adrenaline causes the heart rate and breathing to speed up. It also makes arteries constrict, or get smaller, which raises your blood pressure. The body releases a surge of adrenaline during times of stress, but it continually produces small amounts to keep your blood pressure and heart rate within optimal limits.
Beta-blockers block catecholamine receptor sites, particularly adrenaline, in the heart and arteries.1 When beta-blockers prevent adrenaline from doing its job, the heart rate slows down and arteries cannot constrict, reducing blood pressure.
This effect is important after a heart attack, when the heart muscle surrounding the blockage is weakened. The goal of a beta-blocker is to prevent heart muscle from remodeling, or becoming stiff and fibrous, after a heart attack. Stiff heart muscle cannot pump as efficiently, and this can lead to permanent heart failure.
However, research suggests beta-blockers do not always achieve this goal.
There are many different beta-blockers, but the ones that are used most often to treat heart failure are Zebeta (bisoprolol—now only available as a generic drug), Coreg (carvedilol), and Toprol or Lopressor (metoprolol).
Recent Studies Evaluate Beta-Blocker Use
Three recent studies evaluated the merits of beta-blocker use among either heart attack or heart failure patients. Each concluded that beta-blockers are not right for everyone.
Beta-Blockers After a Heart Attack
Two of the studies looked specifically at heart attack patients.
The first study followed 43,618 patients in Sweden who were prescribed beta-blockers after a heart attack between 2005 and 2016. Researchers concluded that beta-blocker use beyond one year did not improve cardiovascular outcomes for patients who did not develop heart failure after their heart attack.4
The second study reviewed data from 262,972 patients who had their first heart attack between 2018 and 2023. Of these patients, 80% had been prescribed beta-blockers after their heart attacks. Across all demographics of patients, researchers found that patients who received beta-blockers had a 16.5% greater chance of experiencing a second heart attack within the first year.5
Beta-Blockers For Heart Failure
The third study evaluated heart failure patients instead of heart attack survivors, and measured something called ejection fraction.
Ejection fraction (EF) can be an important metric for heart failure that can be measured with an echocardiogram, or heart ultrasound. It refers to the percentage of blood pumped out of the heart’s lower chambers with each beat. The lower the EF, the less efficiently the heart is pumping, resulting in a lack of adequate blood flow through the body.3
- An EF of 50–70% is considered “normal.” Your heart can circulate enough blood to meet your body’s needs.
- An EF of 41–49% is “borderline.” With a slightly lower EF, you may notice some symptoms like shortness of air with activity.
- An EF of 40% or less is significantly reduced. Normal daily activities can become difficult to perform without fatigue, and you may be short of breath at rest.
A low EF can indicate heart failure, but it is not present in all heart failure patients.
Researchers evaluated 435,897 patients aged 65 and older with heart failure on beta-blockers.6 All patients had an EF of 40% and above, so none of the patients had severely reduced heart function. Researchers found that for patients with an EF between 40% and 60%, the benefits of beta-blockers actually decreased as the EF increased.
The researchers also concluded there was no survival benefit to beta-blockers in patients with an EF above 60%. In fact, a patient’s risk of developing heart failure or experiencing hospitalization and death was actually greater if they continued on beta-blockers as EF increased.
What Does This Mean For the Future of Heart Disease Care?
Much of the long-term damage of a heart attack results from lack of blood flow to the heart, and beta-blockers are not the only way to get that back on track.
“We have such good strategies for quickly restoring blood flow to the heart that many of the historical benefits of beta-blockers are negated,” Andy Lee, MD, a cardiologist with UCI Health in Irvine, California, told Verywell.
Stents, cholesterol-lowering medications, and cardiac rehabilitation are other treatment options that reduce recurrent heart disease risk after a heart attack.
The decision to continue beta-blockers can be nuanced, and requires a discussion between the patient and provider.
“Beta-blockers are great drugs for patients that have already had a heart attack, but long-standing beta-blocker therapy is not always indicated,” Lee said. “Someone who is physically active may be more sensitive to being on a beta-blocker. However, if they are experiencing chest pain or have a low EF, a beta-blocker may be more beneficial.”
When it comes to heart failure, beta-blockers still play a vital role in improving long-term outcomes for some patients, especially those with low EF.
“For people with heart failure with weakened heart muscle, beta-blockers remain the standard of care unless they have contraindications,” Deepak L. Bhatt, MD, MPH, Director of Mount Sinai Heart in New York City, told Verywell, adding that patients with atrial fibrillation are also candidates for beta-blocker therapy.
Beta-blockers are only one class of medication used to treat heart failure. Four classes of medications, known as the “four pillars” of heart failure treatment, are recommended for heart failure management. In addition to beta-blockers, a cardiologist may recommend:
- ACE inhibitors, ARBs, or ARNIs: These medications reduce blood pressure and prevent remodeling of the heart muscle.
- Mineralocorticoid receptor antagonists (MRAs): These are mild diuretics. They alleviate excess fluid build-up in heart failure. The most common example is the drug spironolactone.
- Sodium-glucose co-transporter 2 inhibitors: These are a relatively new class of medications originally designed to treat type 2 diabetes. Recent evidence shows they can improve heart function for patients with heart failure with reduced ejection fraction (HFrEF) independent of diabetes status. Farxiga and Jardiance are the most popular drugs in this class for heart failure.
“Professional guidelines continue to be updated. Many of these drugs are underutilized, and we want to encourage providers to prescribe them unless they are contraindicated,” Bhatt said. “The goal is to get all four classes of drugs on board, even if at lower doses.”
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