INNOVATION ARTICLES THE IDEA SUBMISSION PORTAL FROM MEDTRONIC

Researchers have developed a new biomaterial for heart valves that will resemble the natural micro-environment of the heart. This allows the prosthesis to adapt in the body with the hope of reducing possible valve complications.

The researchers used a technique called electrospinning, which is also used in other areas of industry, such as smart textiles, optical applications and in electronics for batteries and sensors.^1,2 Electrospinning is also being researched for biomedical applications due to its versatility, ease and cost effectiveness. The technique allows researchers to pick and choose fibers from various materials, therefore designing a customised and adaptable device.

Electrospun heart valves could add to the current options for heart valve replacement, which are either biological valves made with animal tissue, or artificial mechanical valves, according to the project leader, Dr Costantino Del Gaudio, who heads up the bioengineering department at the Research Consortium Hypatia in Rome, Italy. “We know that mechanical and biological valves obviously work but they do have limitations,” says Del Gaudio, “there can be complications such as hemolysis (the rupturing of red blood cells) or calcification” he explains.

By electrospinning specific microfibersm the Italian research team designed an adaptable valve. Made with biodegradable material, the valve is considered as a scaffold, which can be colonised by cells as it would naturally in the heart, resulting in a functional valve that can modify with the body. “This feature of the valve could be important for paediatric or young patients thereby reducing the need for re-intervention as they grow,” says Del Gaudio.

According to the researchers, this type of tissue-engineered scaffold could be of particular interest for designing aortic valves, that are exposed to structural and functional degeneration. The team created a heart valve scaffold replicated the geometry of the aortic valve and also mimicked the fibrous structure of the natural extracellular matrix.³ Using a cardiovascular simulator, Del Gaudio and his colleagues assessed the valve’s performance by looking at the flow field downstream of the valve. The team found that the device showed good structural resistance to mechanical loads generated by the driving pressure difference and stress values were below the threshold risk for hemolysis.

Del Gaudio initially started out as bioengineer and went onto focus on materials engineering focusing particularly on biomaterials. It has been a collaborative, multi-disciplinary effort explains Del Gaudio. “I have worked with bioengineers and biologists to design the heart valve scaffold, as well as to test the biocompatibility of the materials used.”

“We know that our valves work across a considerable operating range, including various physiological and pathological conditions,” says Del Gaudio. Although the project is still in its early stages, the team has been pleased with their results and hope to move onto in vivo experiments in animal models.

Dr Del Gaudio hopes that he will be able to develop and characterize this type of aortic valve completely. “Currently scientific research related to tissue engineering applications, is trying to find a substitute for the aortic valve, so there is strong support in this field. This kind of tissue engineering could open a large number of opportunities for novel devices that can positively affect the quality of life for patients.”