Animal trials suggest GLP-1 drugs may prevent fatal post-heart attack damage

Weight-loss drugs could help prevent potentially fatal complications following a heart attack, according to new UK research.

Scientists found that GLP-1 medicines, including Ozempic and Wegovy, may reduce the risk of a serious condition known as “no-reflow”, which affects up to half of the 100,000 people who suffer a heart attack in the UK each year. The findings, however, are based on animal model trials, and experts stress that human studies must now confirm the benefits.

Researchers involved in the study concluded that GLP-1 drugs “could offer a promising new therapeutic approach for improving heart attack recovery”.

Doctors already prescribe these medicines to reduce the risk of heart attack and stroke. This marks the first time scientists have explored using them to treat no-reflow, a dangerous complication that occurs even after emergency procedures successfully reopen a blocked artery.

Dr Svetlana Mastitskaya, the study’s lead author and a senior lecturer at Bristol University’s medical school, explained the scale of the problem. In nearly half of heart attack patients, tiny blood vessels within the heart remain constricted despite surgeons clearing the main blocked artery. As a result, blood cannot properly reach parts of the heart muscle.

This failure of circulation, known as no-reflow, significantly increases the risk of death or hospital readmission for heart failure within a year.

Mastitskaya described the team’s findings as surprising. She said their research suggests GLP-1 drugs may prevent this complication from developing in the first place. If confirmed in humans, the treatment approach could begin even before patients reach the hospital.

She told PA Media that paramedics might one day administer the drugs while transporting a patient or during the surgical reopening of the blocked artery. However, she emphasised that clinical trials involving people must take place before such steps become reality.

The British Heart Foundation funded the study, which also involved researchers from University College London. The team published its findings in the journal Nature Communications.

Professor David Attwell of University College London, who co-led the study, described GLP-1 drugs as offering “a potentially life-saving solution” for those affected by no-reflow.

Scientists do not yet fully understand why no-reflow occurs so frequently after a heart attack, even when doctors restore blood flow in the main artery. The latest research suggests that mimicking the action of the natural GLP-1 hormone may improve blood flow through the heart’s smallest vessels, reducing tissue damage.

Professor Bryan Williams, chief scientific and medical officer at the British Heart Foundation, urged caution despite the promising results. He noted that large clinical trials of GLP-1 medicines have already demonstrated broader heart health benefits beyond weight loss. Yet researchers have struggled to explain precisely how the drugs produce those protective effects.

Williams said the new findings offer one possible explanation. By improving circulation in the heart’s microvessels, the medicines may limit the damage that occurs after a heart attack. However, he stressed that detailed human studies and rigorous clinical trials are essential before doctors can consider changing treatment guidelines.

For now, the discovery raises hope rather than certainty. While GLP-1 drugs have transformed weight management and shown cardiovascular benefits, their role in emergency heart attack care remains unproven.

If future trials confirm the early results, the drugs could become an unexpected weapon in the fight to reduce deaths and long-term complications following one of the UK’s leading medical emergencies.