Two chief executives at two of the biggest medical-device companies globally offered different opinions in recent months about the impact of an article about implanted cardioverter defibrillators and a Department of Justice investigation into these products.

Earlier this week, CEO Daniel Starks of Little Canada, Minn.-based St. Jude Medical (NYSE: STJ) was questioned about the impact of an article in the Journal of the American Medical Association that described a study in which 22.5% of patients were implanted with ICDs when there was no evidence that they needed to be. Starks was also asked to comment on the effect of the government's investigation into ICDs. Starks, who was answering questions from analysts after announcing the company's first-quarter earnings call, said the following, according to a transcript of the April 20 call:

"The short answer is that those issues are very small issues, Michael [Weinstein, the JPMorgan analyst who asked the question], with little impact on the global CRM [cardiac rhythm management] market. As we've mentioned, partly in the last call and partly at the Feb. 4 conference, when you look closely at the percent of the available population that is potentially impacted by the JAMA article, it amounted to just a very small percent of the total opportunity and really was not material on a total global basis when we look at the anticipated growth rate of the global CRM market."

However, just two months ago, Medtronic (NYSE: MDT) Chief Executive Bill Hawkins acknowledged that his company had been affected by the article and the DOJ investigation in its quarterly performance. Hawkins responded this way, according to a transcript of the Feb. 22 call:

So on the ICD, yes, the market was, this quarter, down about 1%. And the U.S., we think that there has been some sort of short-term impact because of the JAMA and the DOJ. I think that that is a short-term impact; I think that hospitals are having to adjust a little bit to making sure that they are in conformance with the appropriate guidelines. But I'd take a step back. I continue to be encouraged that this is a large patient population. It is a big market opportunity, and I think we're in just in a little bit of an air pocket here that's a result of the reaction to the JAMA and the DOJ article.

The responses from St. Jude Medical and Medtronic were similar in that both agree that there is a large patient population that will benefit from ICDs. However, while Medtronic acknowledged that ICD sales in the U.S. were hurt, St. Jude, on the other hand, appears unaffected. In fact, Michael Rousseau, St. Jude's group vice president responsible for cardiac rhythm management and the company's U.S. divisions, said that some hospitals are taking longer to process orders and have probably increased scrutiny but that there hasn't been any "significant or material impact to the overall market."

In general, these manufacturers of new innovative medical devices have fared differently in ICD performance, with St. Jude's ICD sales doing better than its in-state rival. St. Jude's ICD revenue in its first quarter ended April 4 was $465 million, up 3% from last year's first quarter. For Medtronic, worldwide ICD revenue of $735 million declined 2% in the quarter ended Jan. 28.

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