The findings, published in Nature Communications, suggest that GLP-1 weight-loss drugs might offer a new strategy to improve recovery after a heart attack.

Earlier research has already shown that GLP-1 weight-loss medications can lower the likelihood of major heart problems. Notably, these benefits appear regardless of a person’s existing health conditions or how much weight they lose while taking the drugs.

Scientists Investigate How GLP-1 Drugs Protect the Heart

To better understand why these medications benefit the heart, researchers examined the biological processes involved. Their earlier work had shown that small contractile cells called pericytes tighten coronary capillaries during the early stages of ischemia, a condition that occurs when the heart muscle is deprived of oxygen-rich blood.

In the new study, the team explored whether GLP-1 drugs could counteract this process and reopen the tiny blood vessels that become blocked.

Dr. Svetlana Mastitskaya, Senior Lecturer in Cardiovascular Regenerative Medicine at Bristol Medical School: Translational Health Sciences (THS) and the study’s lead author, explained: “In nearly half of all heart attack patients, tiny blood vessels within the heart muscle remain narrowed, even after the main artery is cleared during emergency medical treatment. This results in a complication known as ‘no-reflow,’ where blood is unable to reach certain parts of the heart tissue.

“Our previous research has shown that this narrowing of blood vessels contributes significantly to ‘no-reflow,’ a complication that increases the risk of death or hospital admission for heart failure within a year of a heart attack. But our latest findings are surprising in that we have found GLP-1 drugs may prevent this problem.”

GLP-1 Drugs Improve Blood Flow in the Heart

Experiments using animal models revealed that GLP-1 drugs improve blood flow in the heart after a heart attack. The medications activate potassium channels, which relax pericytes and allow previously constricted blood vessels to widen. As a result, blood can reach heart tissue more effectively, lowering the chance of additional damage.

Professor David Attwell, Jodrell Professor of Physiology at UCL, and the study’s co-lead, added: “With an increasing number of similar GLP-1 drugs now being used in clinical practice, for conditions ranging from type 2 diabetes and obesity to kidney disease, our findings highlight the potential for these existing drugs to be repurposed to treat the risk of ‘no-reflow’ in heart attack patients, offering a potentially life-saving solution.”

Dr. Svetlana Mastitskaya is funded by the British Heart Foundation.