The routine approval of implanted medical devices via the 510(k) premarket notification process, and in particular the controversy over Edwards’ Myxo Etlogix annuloplasty ring, get new scrutiny in an article in the Chicago Tribune by Jason Grotto and Deborah Shelton.

The Myxo controversy began in 2008 when a patient who received the device had a poor outcome after receiving the Myxo Etlogix device and discovered that the device had not undergone FDA review because, Edwards claimed,  only a pro forma notification to the FDA was required under the 510(k) process. The patient also complained that her surgeon, Patrick McCarthy of Northwestern Memorial Hospital, had not informed her that he had invented the device. (See heartwire for extensive previous coverage of the controversy.)

The Tribune article adds two important new details to the story:

1. In 1997 AdvaMed, the trade group of medical device manufacturers, successfully petitioned the FDA to reclassify annuloplasty rings so that they would be subject to the less rigorous 510(k) process.

“Our expert team of engineers, statisticians and cardiac surgeons approved the petition after considerable analysis,” said Dr. Bram Zuckerman, director of the agency’s division of cardiovascular devices. “We also did our own independent research and analysis and felt it was appropriate to reclassify the device.”

Yet the Tribune found that the internal memo outlining the reasoning behind the agency’s decision lists a single reviewer: a hydrodynamics and acoustics engineer. What’s more, the memo — called a Reclassification Decision Making Document — consists entirely of paragraphs and charts lifted directly from the industry’s petition.

The agency could not produce any material for the Tribune detailing any independent review or analysis of the petition. Officials said it is rare for them to issue a reclassification decision document that is taken word-for-word from a petition but that they have done so “when the petition is well-written.”

2. In its defense of the Northwestern case, which resulted in a US Senate investigation and an FDA rebuke of Edwards for its handling of the case, Edwards claimed that it didn’t submit the device for clearance because it differed only slightly from previously approved products.

Yet the Tribune found that the company also filed patent applications for one of the rings, listing dozens of ways in which it was different than existing devices.

Nalini Rajamannan, the cardiologist of the patient who received the Myxo device from McCarthy, sent the following comment to CardioBrief:
The story in the Chicago Tribune demonstrates that the Myxo device never went through any clearance process prior to the testing in the patients with myxomatous mitral valve disease. The results of the initial testing was published in the Journal of Thoracic and Cardiovascular Surgery in 2008 without any FDA or any patient knowledge of the testing.
My hope is that the FDA will review the outcomes of the 667 patients who received the Myxo Etiologix model 5100 ring to determine the current clinical status of these patients.
Dr. Rajamannan is an associate professor at the Northwestern University Feinberg School of Medicine and is also affiliated with Prevea Cardiology in Sheboygan, Wisconsin.
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Larry Husten was the editor of TheHeart.Org from its inception in 1999 until December 2008. Before that he was a freelance medical journalist who wrote for The Lancet, The New York Times, Discover, and a large number of other medical and computer publications. In 1994-1995 he was a Knight Science Journalism Fellow at MIT. He received a PHD in English from the State University of New York at Buffalo and drove a taxicab in New York City before embarking on a career in medical journalism.

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