Now, a team of researchers at UBC Okanagan believe they have found a way to harness the advantages of both technologies in a way that could change and save many lives. Dr. Hadi Mohammadi and his fellow researchers at the UBC Okanagan Heart Valve Performance Laboratory are focused on developing the mechanical heart valves of the future.
Dr. Mohammadi, an associate professor in the School of Engineering, says his latest work, called iValve, is the most advanced yet and combines the best of both worlds when it comes to heart valve replacement.
“Tissue valves generally work better than mechanical valves because of their shape, but they only last 15 to 20 years on average, which would require another replacement. Mechanical valves can last a lifetime, but they don’t work as well as tissue valves, requiring patients to take blood thinners daily,” says Dr. Mohammadi.
“We have created a new mechanical heart valve that combines the best of both worlds: it offers the performance of tissue valves with the durability of mechanical valves. We believe this valve could make life easier and safer for patients,” he added.
The innovative valve was made possible through an international collaboration with ViVitro Labs and independent consultants Lawrence Scotten and Rolland Siegel. The research was funded by Angeleno Medical and published this month in the journal Journal of biomechanics.
“This is the only valve of its kind designed and built in Canada,” notes Dr. Mohammadi. “We are incredibly proud of this valve as an example of engineering innovation coming out of UBC and Canada.”
Dr. Mohammadi also says that while mechanical heart valve replacements have long been used, the long-standing challenge has been perfecting the technology for the tiniest hearts — tiny babies.
“What’s particularly interesting about the iValve is that it was specifically designed for applications where the heart rate is elevated, such as in pediatric patients,” explains Dr. Mohammadi.
Now that their prototype is performing well in mechanical laboratory tests, the researchers will take it to clinical and animal trials. If all goes well, they hope the iValve could be ready for those tests within two years.
In the meantime, they will also use the technology and techniques to develop new valves.
“This valve is designed to allow blood flow into the aorta, which is the largest artery in the body and the blood vessel that carries oxygen-rich blood from the heart to the entire body,” Mohammadi explains. “Next, we’ll take what we’ve learned and develop one for the mitral valve. That valve is responsible for ensuring that blood flows from the left atrium to the left ventricle. It also ensures that blood doesn’t flow backwards between those two chambers.”
Dr. Dylan Goode, director of the Heart Valve Performance Laboratory, is excited about what the future holds for iValve and the benefits it could bring to patients.
Dr. Goode began working with Dr. Mohammadi in 2018 while completing his Master of Applied Science in Mechanical Engineering. He recently successfully defended his PhD thesis, which documents his work designing, manufacturing and testing the iValve.
“We have shown that the iValve can provide the structural benefits of a mechanical heart valve and last the patient’s lifetime, while providing improved hemodynamic performance, meaning an improvement in the way blood flows through the vessels.”
Dr. Goode notes that the new iValve could also mean a major lifestyle improvement for these patients who endure a regular routine of anticoagulant (blood thinner) therapy, which can increase the risk of severe bleeding, blood clots or damage to tissues and organs if blood flow is impeded.