Beta Blockers Show No Clinical Benefit After Myocardial Infarction
Recent findings indicate that beta blockers—medications typically prescribed for various heart-related conditions, including heart attacks—do not offer any clinical advantage for patients who have experienced an uncomplicated myocardial infarction with normal heart function. This revelation challenges a treatment standard that has been in place for 40 years.
The new insights come from the “REBOOT Trial,” led by senior investigator Valentin Fuster, MD, PhD, who is the President of Mount Sinai Fuster Heart Hospital and General Director of Spain’s Centro Nacional de Investigaciones Cardiovasculares (CNIC). The results, which might prompt a shift in treatment protocols, were revealed on August 30 during a “Hot Line” session at the European Society of Cardiology Congress in Madrid, and published concurrently in The New England Journal of Medicine.
A related study from REBOOT, released on the same day in the European Heart Journal, found that women taking beta blockers faced a higher risk of mortality, heart attack, or hospitalization for heart failure compared to those who did not use the drug. Interestingly, this elevated risk wasn’t seen in men.
Dr. Fuster stated, “This trial will reshape all international clinical guidelines. It joins other previous landmark trials led by CNIC and Mount Sinai—such as SECURE with the polypill and DapaTAVI, with SLT2 inhibition associated to TAVI—that have already transformed some global approaches to cardiovascular disease.”
For context, the SECURE trial identified that a polypill, which merges three medications—aspirin, ramipril, and atorvastatin—can lower cardiovascular incidents by 33 percent for patients post-heart attack. Similarly, the DapaTAVI trial showed that dapagliflozin and empagliflozin, typically used for diabetes, improve outcomes for patients with aortic stenosis undergoing transcatheter aortic valve implantation.
“REBOOT will change clinical practice worldwide,” asserted Principal Investigator Borja Ibáñez, MD, Scientific Director of CNIC, who presented the findings. “Right now, over 80 percent of patients with uncomplicated myocardial infarction are sent home on beta blockers. The REBOOT findings are among the most important advancements in heart attack treatment in decades.”
While beta blockers are usually deemed safe, they can result in side effects like fatigue, bradycardia (slow heart rate), and sexual dysfunction. After more than four decades as a go-to treatment following heart attacks, their effectiveness—especially in light of modern methods—has been questionable. The REBOOT trial stands as the largest research project on this topic, coordinated by CNIC alongside the Mario Negri Institute for Pharmacological Research in Milan.
The study involved 8,505 patients from 109 hospitals spread across Spain and Italy. Participants were randomly assigned to either receive or not receive beta blockers after leaving the hospital, while everyone else received the standard care and were monitored for nearly four years. The results showed no significant differences in death rates, recurrent heart attacks, or heart failure hospitalizations between the two groups.
A subgroup analysis pointed out that women treated with beta blockers had a 2.7 percent higher absolute risk of mortality compared to their counterparts not on the medication during the follow-up period of 3.7 years. This increased risk was primarily seen in women with normal cardiac function post-heart attack (left ventricular ejection fraction of 50 percent or more). Women with mild declines in cardiac function did not show an additional risk associated with beta blockers.
Dr. Ibáñez explained, “After a heart attack, patients usually take multiple medications, which can be challenging to manage. Beta blockers were integrated into treatment protocols early on due to their significant reduction in mortality benefits at the time, mainly associated with reduced cardiac oxygen demand and arrhythmia prevention. However, clinical methods have progressed. Nowadays, blocked coronary arteries are quickly and systematically treated, significantly lowering the chances of serious complications like arrhythmias. Given this new situation—where heart damage is often less severe—the necessity for beta blockers is increasingly uncertain. It’s easier to test new medications than to rigorously evaluate the ongoing need for older ones.”
That’s ultimately what spurred the REBOOT trial.
Dr. Ibáñez concluded, “The trial was crafted to enhance heart attack treatment backed by solid scientific research and without commercial interests. These results aim to simplify treatment, lessen side effects, and elevate the quality of life for a multitude of patients every year.”
It’s worth noting that REBOOT was conducted without any pharmaceutical industry funding.
