St. Jude Medical is asking a journal to retract a study by a Minneapolis cardiologist.
The study by Dr. Robert Hauser published in the journal "Heart Rhythm" looked at defective wiring in the company's implanted heart rhythm devices. The study linked St. Jude's wiring to at least 20 deaths.
St. Jude says the study contains inaccuracies — and a biased analysis of the Food and Drug Administration's database of device malfunctions.
The company says its own researchers have spent more than 300 hours trying to replicate the study's results. They haven't been able to do so.
St. Jude stopped selling the Rita and Rita ST wires in December 2010 due to safety concerns. But thousands of people still have the implants.
Hauser, the study's author, says in a written statement that he stands by his research findings.