Beta-Blockers Post MI; Is it Safe to Stop?

Written by Joseph Kummer, MD, FACC

There is hardly an area of cardiology where beta-blockers have not been helpful. For many decades, these medications have shown significant benefit for patients with ischemic coronary disease, heart failure, valvular heart disease, hypertension, and multiple rhythm disorders.

For many years, beta-blocker therapy has been a hallmark of treatment for virtually all patients who have had a myocardial infarction (MI) due to previous trials showing post-MI mortality reduced 20% with use of beta-blockers. However, as treatment for ischemic coronary disease has progressed, we’ve seen great advancements in the quality and quantity of life for patients following an acute coronary syndrome. Recently, data has called into question the benefit of beta-blockers in patients who have received current medical and interventional strategies for their coronary events. Prompt and effective coronary reperfusion, aggressive control of risk factors, and contemporary pharmaceuticals may have diminished the relative benefit of beta-blockers for some individuals today compared to their proven benefit several years ago.

To evaluate this, the REDUCE-AMI trial (NEJM, (390)15: 1372-1382) randomized patients with a prior MI who underwent coronary angiography to beta-blocker therapy with long-acting metoprolol or bisoprolol versus no beta-blocker.

Study Details -

• This was an open label study that was not blinded.
• Mean follow-up was 3.5 years.
• All patients had an ejection fraction of 50% or greater assessed by an echocardiogram within a week of their ischemic event.

Study Findings -

• There was no difference in any of the multiple outcomes assessed, including cardiac and all-cause mortality, recurrent myocardial infarction, heart failure, atrial fibrillation, angina, dyspnea, etc.
• There was also no difference in safety outcomes such as bradycardia, hypotension, syncope, or advanced heart block.

This study in conjunction with prior data is sufficient to show that we should no longer feel compelled to use beta-blockers in all post-infarct patients. The important consideration should likely be whether there is a compelling indication for using a beta-blocker otherwise. Of course, this is often the case.

It is important to recall that this study only enrolled patients who had normal ejection fractions. We should still use beta-blockers for patients with impaired systolic function and heart failure. Those with atrial fibrillation or other arrhythmias of course often will benefit from these medications for symptomatic relief as well as those with chronic stable angina. Although beta-blockers should not routinely be used first line for the treatment of hypertension, these are appropriate if hypertension is still present despite treatment with RAAS agents, diuretics, and calcium channel blockers.

Most current guidelines still recommend therapy indefinitely for all post-MI patients, but that will likely soon change. There is a current trend to use beta-blockers for at least a year following an MI. It is anticipated that the next guidelines will recommend that after perhaps one to three years, for those with normal systolic function and no other compelling indication for a beta-blocker, it is appropriate to consider discontinuation. This may help simplify the patient’s medical regimen, reduce side effects, or potentially allow for titration of other medications which may be more helpful.