University Hospital is one of a handful of centers nationwide testing a new-generation heart pump as a permanent alternative to heart transplants for patients with congestive heart failure.
The VentrAssist, a left ventricular assist device, has a single moving part an impeller and weighs just 10 ounces. Its small diameter, 2.5 inches, means it could be used in smaller adults and in children who are not large enough to accommodate larger LVADS, according to Dr. Craig Selzman, associate professor of cardiothoracic surgery and principal investigator.
There are now a number of LVAD designs, the goal being smaller, more user-friendly implants that will not wear out as fast as earlier models. Key to that is eliminating friction and moving parts in the device, which can be employed to be a bridge to transplant, a tool to allow the ailing heart to recover or as a destination therapy itself, especially for patients who would not qualify for a transplant. So far, a single LVAD, the HeartMate made by Thoratec, has been approved by the Food and Drug Administration as a destination. A number of models are available as a bridge to transplant.
The LVAD the U. is now testing, the VentrAssist by Ventricor, an Australian company, has a single impeller, suspended in fluid. That impeller has a diamondlike carbon coating where it contacts blood, to eliminate the damage that LVADS sometimes cause blood. Earlier pulsatile models push blood around and can damage it.
A number of heart pumps are currently in trial phases.
Selzman said the VentrAssist has particular benefits for smaller patients. And it's as easy to put in as other LVADS. "The surgeries are not difficult, it's the patients who are difficult because they're so sick," he said.The Ventricor device is currently involved with two trials, one to see if it works well as a bridge to transplant and the other to check it out as destination therapy. The latter is a two-armed trial, with one comparing medical therapy versus the pump. The other arm pits the HeartMate I against it. That means patients in that trial have one chance they'll be randomized into medical therapy and two chances they'll instead receive a heart assist device. For patients for whom medicine is simply not an option, the choice is between the two types of LVADs.