Injectable Hydrogel First Treatment to Repair Heart Damage After Stroke

Bioengineers from the University of California, San Diego have demonstrated a new injectable hydrogel that can repair damage from heart attacks, help the heart grow new tissue and blood vessels, and get the heart moving closer to how a healthy heart should in a study in pigs. The gel is injected through a catheter without requiring surgery or general anesthesia — a less invasive procedure for patients.

Lead researcher Karen Christman, a professor in the Department of Bioengineering at UC San Diego, said the gel forms a scaffold in damaged areas of the heart, encouraging new cell growth and repair. Because the gel is made from heart tissue taken from pigs, the damaged heart responds positively, creating a harmonious environment for rebuilding, rather than setting off a chain of adverse immune system defenses.

“While more people today are initially surviving heart attacks, many will eventually go into heart failure,” said Christman. “Our data show that this hydrogel can increase cardiac muscle and reduce scar tissue in the region damaged by the heart attack, which prevents heart failure. These results suggest this may be a novel minimally invasive therapy to prevent heart failure after a heart attack in humans.”

This new method could become highly relevant, since there are an estimated 785,000 new heart attack cases in the United States each year, with no established treatment for repairing the resulting damage to cardiac tissue.

The university explains that "the hydrogel is made from cardiac connective tissue that is stripped of heart muscle cells through a cleansing process, freeze-dried and milled into powder form, and then liquefied into a fluid that can be easily injected into the heart. Once it hits body temperature, the liquid turns into a semi-solid, porous gel that encourages cells to repopulate areas of damaged cardiac tissue and to improve heart function. The material is also biocompatible; animals treated with the hydrogel suffered no adverse effects such as inflammation, lesions or arrhythmic heart beating, according to safety experiments conducted as part of the study. Further tests with human blood samples showed that the gel had no affect on the blood’s clotting ability, which underscores the biocompatibility of the treatment for use in humans.