NIH funds WPI heart valve study



Research at Worcester Polytechnic Institute aimed at creating more natural and durable replacement heart valves is getting a boost from the National Institutes of Health, the school announced Wednesday.
The federal $450,000 grant will be used by a team lead by Kristen Billiar, professor of biomedical engineering, for a three-year study exploring how mechanical forces and cellular growth factors affect heart valve biology.
In a statement from WPI, she said the goal of the research is to help develop a new class of tissue-engineered heart valves that may improve the quality of life for the 300,000 people who undergo heart valve replacement surgery each year worldwide.
“Right now, if you are a young person who needs a new heart valve, you are going to face several surgeries over the course of your life because the replacement valve will, itself, eventually need to be replaced,” Billiar said. “Our hope is to contribute to the field with new knowledge that advances development of a better treatment option.”
When the body’s hard-working heart valves don’t work properly because of disease or a congenital defect, the result can be heart failure, stroke or blood clots. Patients needing replacement heart valve surgery typically receive either a mechanical valve made of a stiff carbon material, or a bioprosthetic valve compose either of pig or human-donor tissue, the statement said. Mechanical valves require patients to take blood thinners the rest of their lives; while a problem with bioprosthetic valves is that they degrade over time.
Several labs around the world are trying to bioengineer new heart valves by growing human cells on scaffolds, but have run into problems with tissue retraction and leakage, the statement said. Aiming to improve this approach, the WPI team will explore how proteins called cellular growth factors that are active during embryonic development regulate heart valve tissue in concert with the mechanical forces experienced during cardiac function and growth.
“If we can better understand the mechanisms of valve tissue development, then we may be able to engineer a heart valve that doesn’t retract, and in the case of young persons, may actually grow with patients over time as they mature,” Billiar said. “But the first step is to get a better understanding of the biomechanics, which is what we hope to do in this study.”