A federal appeals court has ruled against Medtronic in a patent infringement case over a promising new heart valve.

The U.S. Circuit Court of Appeals in Washington, D.C., on Tuesday upheld a jury's $73 million award against Fridley-based Medtronic, which had been accused of patent infringement by competitor Edwards Lifesciences.

"While we respect the court's ruling, we respectfully disagree with this conclusion and we are evaluating next steps," said Kathleen Janasz, a Medtronic spokeswoman.

The case involves Medtronic's CoreValve device, which replaces a diseased aortic valve without open-heart surgery. The valve, made from pig cardiac tissue, is mounted on a stent and implanted in the heart via a catheter.

Irvine, Calif.-based Edwards, maker of a rival product to CoreValve, sued Medtronic in 2009 in U.S. District Court in Delaware. A jury found that CoreValve willfully infringed on an Edwards patent and awarded the firm $72.6 million for lost profit.

The U.S. Food and Drug Administration has approved Edwards' non-surgical valve for sale in this country. Medtronic's CoreValve is still in trials with the FDA, and is expected to be approved in 2014.

The appellate court decision does not affect the FDA approval process and U.S. commercial rollout of CoreValve, Janasz said.

In fact, the case may end up having very little obvious impact on the market. It is possible that if Edwards wins an injunction in the U.S., Medtronic may have to move the marketing of its valve outside the country. In the end, in many medical device patent cases, one side simply ends up having to pay the other to continue selling its product.

CoreValve was approved in Europe in 2007 and has been implanted in more than 30,000 patients in 60 countries outside the U.S.

It is a potentially lifesaving product for people diagnosed with aortic stenosis but who are too old or frail to survive open-heart surgery -- the usual method of implanting a replacement valve.

Mike Hughlett • 612-673-7003 Staff writer James Walsh contributed to this report.