Dr. Padala Receives NIH R41 Grant to Develop Polymeric Heart Valve

June 2012

Bioprosthetic heart valves (BHV) have been used for valvular replacement since the 1980s, but can deteriorate over time due to such forces as calcification and may eventually require replacement. While mechanical valves fail less frequently than BHV, they can experience such problems as blood clots. In recent years, the search for a more durable artificial heart valve has turned to the development of biocompatible, polymeric heart valves (PHV).

"Polymeric valves can offer improved durability, tunable surface properties that can reduce calcification, and the ability to program hemocompatibility to avoid thrombogenesis," says Dr. Muralidhar Padala, director of the structural heart disease research and innovation lab of Emory's Cardiothoracic Surgery Research Laboratory (CTRL). "However, one valve that combines all three advantages is yet to be developed."

Dr. Padala hopes to do just that as the PI of a new NIH R41 grant, an award the NIH gives under the Small Business Technology Transfer Program to fund research and development of new technologies and methodologies that have the potential to succeed as commercial products. In collaboration with MedShape Solutions Inc., an Atlanta-based medical device company that harnesses the unique transformational capabilities of new biomaterials, Dr. Padala and his team will develop a new polymeric heart valve using a novel ultra-polymer called polyetheretherketone (PEEK).

"PEEK is superior to traditional polymers and is widely used for implantable devices," says Dr. Padala. "It has excellent fatigue resistance, low water absorption, highly inert structure, is likely to be hemocompatible, and its structures can be molded into complex shapes, woven, and/or non-woven to avoid regions of stress concentration, which is where structural failure of BHV occurs."

PEEK can be processed to demonstrate shape memory—the ability to "remember" multiple shapes and transition easily between those shapes when triggered—and can recover its original shape after deformation without loss of mechanical integrity. In addition to providing an ideal materials solution for traditional artificial heart valves, PEEK's shape-shifting component could allow its use for transcatheter aortic valves.

The partnership of Dr. Padala's team with MedShape is a model of synergy, as Emory's expertise and resources in heart valve development and testing is invigorated with MedShape's experience in polymer innovation, processing, and commercialization of FDA-approved polymeric devices.