Engineers and physicians find common ground in basic physics to develop a pulseless artificial heart powered by the human body's own energy.
For the past three years, a team of Cameron engineers, Texas Heart Institute doctors, and Rice University students has been working to develop a pulseless artificial heart that can be run by a device that harvests human energy from walking.
The artificial heart project has been an excellent example of the power of cooperation and collaboration between seemingly unrelated technical fields – the medical world and the heavy-equipment sector of the oil and gas industry. The pulseless heart device is on the verge of being the first practical, safe, and reproducible replacement for the failing human heart, which could have a significant impact on humanity worldwide.
The heart is considered the most complex organ in the human body, as well as one of the most precious. Approximately 400,000 Americans die every year from heart failure due to the long-term effects of the wear and tear that the heart endures. Currently, surgeons are able to transplant only about 2000 donor hearts each year.
Working with physicians at the Texas Heart Institute at St. Luke's Episcopal Hospital in Houston, Texas, volunteer engineers from Cameron are developing a sustainable solution to this problem: a pulseless artificial heart based on Cameron's valve and compression technology being used in the oilfield.
Adapting Oilfield Technology for the Medical Field
The processes of pumping oil in the field and pumping blood in our own bodies are quite different, however the similarities in certain areas allow the technology from the oilfield to be adapted for the medical field.
The human heart is similar to pumps used in the oil and gas industry, as both facilitate the transportation of fluids to several critical points throughout their respective systems. The veins in our bodies carry blood the same way pipes carry fluids or other resources within an oil or gas system's infrastructure.
Cameron engineers understand how much technology is required to design and manufacture equipment that is used two miles underwater in saltwater conditions, sometimes operating more than 20 years without human intervention. While designing the artificial heart, the engineers utilized this type of experience to address issues that are encountered in the medical field, including difficult environments (e.g., finding a viable, long-term power source and compatibility with the body and blood) and the need for reduced human intervention (e.g., number of battery changes required throughout the life of the artificial heart device). And the kidneys serve the same purpose for our bodies as filters do during oil and gas processing.
How the Pulseless Heart Works
There is a clear juxtaposition between the heavy-duty technology of the oil and gas industry and the intricate technology of the human heart, however both disciplines are based on simple physics.
The basis for the heart design is a centrifugal pump, which is being adapted from Cameron's experience with large industrial centrifugal compressors that range in size from 200 to several thousand horsepower. In these machines, spinning impellers impart velocity to the fluid, which ultimately is converted into a pressure energy that results in the flow of fluid along the intended path.
In the artificial heart, two rapidly spinning discs take blood from the body and blood returning from the lungs and continuously pump it back to the lungs and throughout the rest of the body. This pumping process is a continuous flow technology instead of a pulsatile one, making the need for a heartbeat obsolete.
Future of the Technology
There are several technical obstacles that must be overcome moving forward, including hydrodynamics, blood composition and its behaviors, size and weight of the device, and issues with hydraulic forces, among others.
The team of Cameron engineers and Texas Heart Institute physicians has developed a prototype using 3D printing and currently is testing the pumps using synthetic blood. They also are working on the motor design. Eventually, the device will be made of titanium and implanted for testing.
In addition, the team has partnered with Rice University in Houston to conceptualize a sustainable power source for the artificial heart, which involves generating power using the motion of the human body. The original design, known as PediPower shoes, can turn motion into electricity and extract and store energy with every step.
Recently, the third group of students to take on the multiyear project has pushed this technology forward. Sponsored by Cameron Engineering Fellow Omar Kabir and our Corporate VP of Enabling Technology, John Bartos, the current student team designed a knee brace to amplify the motion of a knee as it bends. It also includes a new power conversion and storage system that the shoe did not have. Although the knee brace is not yet powerful enough for the artificial heart, the team of engineers, doctors, and students are excited by the potential of this third-generation device.