A 16-year-old boy has returned to school and a young Utah mother is raising her newborn at home, thanks to a portable heart-assistance device that may someday be a permanent solution to end-stage heart failure for some patients.

Tuesday the Food and Drug Administration approved commercial use of implantable electric heart-assist systems that allow people to leave the hospital and resume their lives while they wait for a heart transplant.LDS Hospital is one of 25 sites that tested one of the devices, the Heartmate, in clinical trials, implanting 27 in patients in the last four years, including the young mother and the student.

According to John Marks, clinical coordinator for mechanical circulatory support services at the hospital, 90 percent of the patients who received the 2-kilogram device have survived who otherwise would have died.

LDS Hospital is one of a handful of hospitals nationwide named to take part in a clinical trial to see if the device can be used as a permanent alternative to heart transplants. About 2,000 donor hearts are transplanted each year in the United States, while 20,000 people die of heart failure while waiting, said hospital spokesman Jess Gomez.

"We haven't done the first patient," he said. "We are waiting for a very good candidate, since it won't be taken out and whoever it is will essentially live the rest of his life on it. But it's portable enough and flexible enough to provide a high quality of life."

The Heartmate device is made by Baxter Inc. and Thermo CardioSystems Inc. In the past, patients with advanced heart failure were connected to a cumbersome machine that mechanically pumps the heart. The newly approved device is completely portable.

It is implanted in the abdomen and connected to the heart's left ventricle, the main pumping chamber. It circulates blood through the body, powered by a small battery pack worn at the patient's waist or shoulder.

The FDA approval thrills the hospital clinical trial team, led by Dr. James W. Long.

"This is different because we can now, with full FDA backing, use the portable, cost-effective technology to allow people to return to their normal lives," Marks said.

The payoff includes reduced health care costs as hospital stays are reduced, he said.