Oct. 18, 2021 — After a heart attack, the damaged area of the heart often becomes scar tissue that can’t receive electrical messages to contract and pump blood to the body. The result is a weakened heart that could get an irregular beat, known as an arrhythmia, or go into failure.

Right now, doctors have two imperfect options for repairing this damaged tissue. One is to surgically implant a scaffold that conducts electrically and bridges the heart’s signaling system past the dead tissue. But these implants require open-chest surgery, which is risky and can lead to other heart problems.

Clinicians can use an approach that avoids opening the chest, but the patch used for these procedures may not hold its shape when grafted to damaged tissue.

Now, scientists may be working on a fix that promises the best of both worlds: an injectable patch that conducts electricity and keeps its shape once grafted to heart muscle.

The patch hasn’t been tested in humans — any such trials are still a long way off — but early results in animals show potential.

This experimental patch can be rolled up, threaded into a catheter or a syringe, and injected into damaged heart tissue, where it unfurls and attaches to the muscle. Once in place, the patch supports normal heart function, according to results from studies using rats and pigs. The findings were published inNature Biomedical Engineering.

When researchers placed the patch on damaged heart muscle in rats, they found this fix resulted in a return to mostly normal heart function within 4 weeks. Results were similar when scientists tested the patch in a small number of pigs, which are considered to resemble humans more closely than rodents.

The patched hearts did a better job in pumping oxygen-rich blood to the body, and the amount of heart tissue that wasn’t getting enough oxygen also declined.