It would be hard to imagine a more compelling or challenging project to tackle than creating a wireless communication system for a ventricular assist device (VAD), but that’s exactly what Device Solutions was asked to do in 2013.
Simply put, a VAD is a mechanical pump that helps support heart function and blood flow in people with weakened hearts. The device takes blood from a lower chamber of the heart and helps pump it throughout the body. VADs can be used to assist the left, right or both ventricles of the heart, but the most common is the LVAD. It helps the left ventricle pump blood to the aorta. VADs were originally developed to serve as a temporary bridge to heart recovery, and then as a bridge to transplant. Over the past 10 years, however, VADs have been approved by the US Food and Drug Administration to provide permanent or lifetime support for patients with end-stage heart failure.
Caption: Illustration of one of the first external VADS Caption: Illustration of one of the first internal LVADs
(image credit National Institutes of Health)
The specific VAD Device Solutions was asked to collaborate on is the LVAD produced by ReliantHeart Inc. known as the HeartAssist5 (HA5). Unlike the very first VADS, which were cumbersome external devices powered by 300 lb tanks of compressed air, the HeartAssist5 is small 71mm x 38mm internal pump that is implanted within a patient’s chest cavity.
The HA5’s predecessors were developed through a unique collaboration between engineers at Johnson Space Center, famed heart surgeons Drs. DeBakey and Noon at the DeBakey Heart Center at Baylor College, and researchers in NASA’s Advanced Supercomputing (NAS) Division. The Johnson engineers built several versions of an internal device based on the criteria and feedback supplied by DeBakey’s medical team, then the NASA team used their supercomputers and computational fluid dynamics technology to analyze blood flow through the battery-powered pump. As a result of this analysis, NASA was able to suggest design improvements that solved the problem of blood cells being damaged by friction, and clotting caused by stagnant regions in the pump. The first successful implantation of a left ventricular assist device was completed in 1966 by Dr. DeBakey.
Caption: Inside the HeartAssist5 controller
ReliantHeart Inc. first approached Device Solutions in 2013 for help with their HeartAssistRemote Monitoring System. The technology included in the HeartAssist5’s flow sensor consistently measures real-time blood flow and tracks speed and electrical current usage by the pump’s motor. This invaluable information is sent via the LVAD’s “drive line” to the “Conquest2 Controller,” the external device which powers and controls the LVAD. Device Solutions’ expertise was needed to send this data via 2G cellular networks to secure computers and wireless devices so that patients could be monitored remotely by their medical teams.
According to William Graham, ReliantHeart’s Director of Engineering, Device Solutions work on HeartAssistRemote was outstanding. “It was a huge accomplishment. Device solutions had to analyze the entire system and modify each component of the controller to operate with the cellular module.” Device Solutions is now hard at work helping ReliantHeart make the transition from 2G to 3G cellular technology and collaborating on developing a Transcutaneous Energy Transfer System (TET) for the HeartAssist5. This means that the HA5 will be powered by an internal battery, which will be recharged through the skin. This will eliminate the need for wires exiting the body, dramatically reducing the chance of infection.
Caption: Illustration of HeartAssist5 new TET system
Mike Sink, Device Solutions’ project manager overseeing this next phase of the collaboration says that he’s proud of Device Solutions’ increased involvement and is looking forward to the system testing phase. “That’s when all the different components by all the different companies working on the project get integrated and we see how it all works together.”
For his part, Device Solutions’ co-founder and CTO Chris Lamb is proud not only of the work Device Solutions has done but excited by the opportunity to make a real difference in people’s lives. “What can I say? I’m the geek who likes to make things work,” he says, “and the challenge of making a device that helps people in the real-world just makes it better.”
– Jena Ball