April 21 (Reuters) - A U.S. appeals court on Monday postponed an injunction that would have stopped Medtronic Inc from selling its CoreValve heart valve implant in competition with Edwards Lifesciences Corp's Sapien valve product.
The injunction, issued by a U.S. District Court in Delaware last week, would have taken effect on April 23.
Earlier court decisions found Medtronic's product infringed on the Edwards valve.
Monday's ruling means the injunction would take effect only if the appellate court determined it was properly issued, Medtronic said.
Medtronic is appealing the injunction with the Federal Circuit Court of Appeals, which has agreed to an expedited appeal, requiring the last appeal brief to be submitted by June 19.
"This stay of injunction should come as some relief to Medtronic investors who were shocked when Edwards was granted a preliminary injunction on CoreValve a week ago," Bernstein Research analyst Derrick Sung wrote in a note to clients.
Investors and physicians had assumed that the benefit to patients' health would have prevented an injunction from being issued, Sung said.
Both companies' implants use a less-invasive procedure that spares patients from undergoing traditional open-heart surgery for valve replacement.
Medtronic's CoreValve system for replacing diseased aortic heart valves led to a significantly higher survival rate after one year than open heart surgery in patients deemed at high risk of death during surgery, according to data the company presented at a conference in March.
CoreValve won U.S. approval in January to treat patients considered too frail for open heart surgery, becoming the first such device to compete against Edwards' Sapien valve in the United States. (Reporting by Susan Kelly in Chicago)