Novel Mechanical Heart Valve Improves Blood Flow and Lowers Risk of Blood Clots

Calcific valvular heart disease, which occurs when one or more of the heart's valves fail to open or close properly due to calcification, is expected to affect around 4.5 million people by 2030, making it the most common valvular heart condition among aging populations. For treating this condition, aortic valve replacement options typically involve implanting either mechanical valves or those made from natural tissues, such as bovine or porcine tissue. Both options, however, come with limitations. While tissue valves provide better blood flow and generally perform better than mechanical heart valves (MHVs), they only last for 10 to 15 years, often requiring another replacement. Mechanical valves, on the other hand, can last a lifetime but do not perform as well as tissue valves, and patients must take daily blood thinners to reduce the risk of clotting. Despite advances in prosthetic heart valves, finding the ideal solution remains a challenge. Now, a new MHV, after clinical trials, may eventually replace the current mechanical valves for patients with heart disease. The latest research published in the Journal of Biomechanics indicates that MHVs could outperform tissue valves in certain conditions.

Researchers at UBC Okanagan (Kelowna, BC, Canada) have been evaluating several MHVs, and the one designed in their lab seems to outperform the others. Their study assesses two emerging MHVs, which are in preclinical and clinical trials, and are designed to address the limitations of earlier models. The iValve, developed in their lab, combines the best qualities of both mechanical and tissue valves for heart valve replacement. The researchers tested the iValve alongside another valve in development, Triflo MHV. These two valves, along with three other valves similar to the current industry standard, were fully tested in the study. Using a pulse duplicator system that mimics real heart conditions, each valve underwent 10 cycles and multiple tests to evaluate flow velocity.

The results showed that the iValve and Triflo MHV achieved comparable pressure ratios and significantly lower mean and peak reverse blood flow values compared to traditional MHVs. This indicates that blood flows more smoothly through the iValve, putting less stress on blood cells and potentially reducing the need for blood thinners. Unlike most MHVs, the iValve features a single open central orifice through which blood flows, similar to tissue valves. Other MHVs, including the Triflo MHV, split the flow into smaller streams, which could increase the risk of flow-related complications. This design gives the iValve a potential advantage in providing safer, smoother blood flow, according to the researchers. The iValve is now preparing for animal and clinical trials, bringing it closer to becoming a viable solution for patients.

“Overall, both the iValve and Triflo MHV appear to offer better performance than existing MHVs,” said researcher Dr. Dylan Goode. “These results show that the new generation of mechanical valves may offer a strong combination of long-lasting performance, better blood flow and lower risk of blood clots—similar to how a natural heart valve works.”