Research Shows Beta Blockers May Be Ineffective After A Heart Attack

Medicines with beta blockers have been part of the standard treatment for heart attacks for over 30 years to reduce the risk of new heart attacks. But now a new study, in which roughly 43,000 Swedish heart attack patients were included, points to the fact that these drugs have no effect in the vast majority after one year.

– These preparations with beta blockers were studied during the 60s, 70s and 80s. Then they proved to be effective in patients with heart attacks, but since then a lot has happened with heart attack care. Among other things, we do more balloon bursts and stents and give other treatment, for example blood lipid-lowering and more potent blood-thinning drugs that mean that the beta blockers may no longer be needed, says Gorav Batra researcher at the Department of Medical Sciences and Uppsala Clinical Research Center (UCR).

Fewer get heart failure
The chances of surviving a heart attack are significantly better today than they were in the past. In the past, heart failure was also a very common complication of heart attacks, and beta blockers are documented to be effective in heart failure. However, significantly fewer heart attack patients suffer from heart failure today thanks to faster care interventions and treatment.

– It may be that beta blockers are useful in the short first time, but not over a longer period of time. That’s why we started looking at heart attack patients one year after the heart attack. We looked at those who were on beta-blockers compared to those who did not. Then we studied the combined outcome that included death, new heart attack, new revascularization, that is, another balloon burst or whether you were admitted for heart failure, because those are serious diseases that we want to avoid. We saw that beta-blockers had no effect when it came to this pooled outcome, explains Gorav Batra.

Registry study
In the study, roughly 43,000 heart attack patients from the national Swedish quality registry for coronary artery disease SWEDEHEART were followed. They had suffered a heart attack in 2005–2016 and none had developed heart failure when the study began. The researchers also retrieved information from the Patient Register, the Cause of Death Register and the Medicines Register to see what treatment the patients received and whether, during the 4.5 years they were followed, they ended up in the hospital or died.

Because it was a registry study, the researchers could not investigate whether there were differences in quality of life between the patients who took beta blockers and those who did not. The preparations, just like other medicines, have known side effects.

– It is above all fatigue. Some of my patients experience it. Some may feel depressed and some patients may have nightmares. They are not very many, but sometimes you can see it, says Gorav Batra.

Some patients also experience a deterioration in fitness, which can lead to them not being able to be as physically active as they should be.

More studies underway
Although the results in the study clearly point to beta blockers having no long-term effect on patients who had a heart attack but did not develop heart failure, it is not possible to draw any far-reaching conclusions from a single study. Before it could become relevant to change the recommendations, randomized clinical trials are needed that show the same results.

– Fortunately, large randomized studies are underway in this area, including one in Sweden where patients are randomly assigned to either receive beta blockers or no such treatment. We in Uppsala are also involved and include patients in this study. We will probably have results from this study quite soon, says Gorav Batra.