A new type of pump to help failing hearts will undergo clinical trials in autumn 2004 in the UK. The pump has a curious side effect: people implanted with the device have no pulse.
What makes the VentrAssist different is that it only has one moving part, a spinning impeller that drives a continuous stream of blood. That means the pulse is replaced by a gentle whirling noise that patients describe as similar to the sound of a washing machine. More importantly, the device prevents blood from stagnating, reducing the risk of clotting.
Six copper coils within the device's titanium walls generate magnetic fields that make the magnet-cored impeller blades spin. The blades push blood out to the body while forming a high-pressure, liquid cushion that levitates the impeller and holds it steady.
"There is no predicted lifespan for VentrAssist because there are no wearing parts," says co-inventor of the device and company founder John Woodard. "It could be a hundred years, we don't know."