Problem: Over 85,000 Americans receive artificial heart valves, but such valves don’t last forever, and replacing them involves a costly and invasive surgery. In children, they must be replaced repeatedly.

Solution: Svenja Hinderer, who leads a research group at the Fraunhofer Institute in Stuttgart, Germany, has created a biodegradable heart valve that studies strongly suggest will be replaced over time by a patient’s own cells.

To accomplish this, Hinderer created a scaffolding of biodegradable fibers that mimic the elastic properties of healthy tissues. To it she attaches proteins with the power to attract the stem cells that naturally circulate in the blood. The idea is that once implanted, her heart valve would be colonized and then replaced by a patient’s own cells within two to three years.

—Russ Juskalian