Watchdog cautious on new Boston Sci defibrillator

A Minneapolis cardiologist who is internationally known for exposing safety problems in heart defibrillator wires says more needs to be learned about a new device that keeps wires out of the heart before doctors put it into widespread use.

Dr. Robert Hauser of the Minneapolis Heart Institute Foundation is not raising an alarm. But he said the new device by Boston Scientific Corp. needs more study comparing its safety and effectiveness to traditional defibrillators.

"I believe the S-ICD is a very promising technology," Hauser said in an interview Wednesday. "If it is as safe and effective as transvenous ICDs, its less-invasive approach offers the potential of a better therapy. But we need to prove it. And we need to prove it in different patient populations."

Boston Scientific, a major medical technology player with thousands of Minnesota employees, made a huge investment in the technology and is banking on big things for its subcutaneous implantable cardioverter defibrillator (S-ICD) -- including attracting patients who have seen traditional defibrillators, with their wires that run through veins into the heart, as too risky. Problems with the leads fracturing or failing have been linked to patient deaths.

But Hauser is pressing doctors and patients to avoid rushing to use the new device until there is more data on whether it is as safe and as effective as traditional defibrillators.

Dr. Kenneth Stein, chief medical officer for Boston Scientific's cardiac rhythm management division, on Wednesday said the device is safe, noting that the FDA approved its sale after "looking at the totality of the data." He did agree more study needs to be -- and will be -- done on the device's effectiveness.

"There is probably more that we agree with him about than disagree with," Stein said of Hauser's concerns.

The device was approved in September for sale in the United States by the U.S. Food and Drug Administration. Officials at Boston Scientific, one of the world's largest medical device companies with about 5,000 Minnesota employees, have said it could eventually mean $1 billion in worldwide revenue.

It is the world's first defibrillator that does not connect to the heart with wires. In fact, the device delivers its jolt without actually touching the heart at all. A lead runs beneath the skin from the device to just above the breastbone.

The S-ICD was developed by Cameron Health Inc., based in California. Boston Scientific bought Cameron in 2012 for more than $1 billion.

When the S-ICD was approved by the FDA, Boston Scientific officials said they expect the S-ICD will not only attract patients who have not been able to benefit from such technology in the past because of complications, they think it will attract doctors and patients who have been scared off by problems associated with leads.

Leads that run through the vascular system into the heart have come under increasing scrutiny in the past few years. Short circuits caused by faulty wires have been associated with several deaths. Inner wires breaking through the outer insulation of St. Jude Medical Inc.'s recalled Riata leads have raised fears that some ICDs will fail to deliver a shock to the heart when needed. Medtronic Inc.'s Sprint Fidelis leads were pulled off the market in 2007 after a study found that some of the wires failed. Hauser has played a key role in raising concerns about both those leads.

Hauser, too, said it could be a good device for certain patients. But Boston Scientific should conduct clinical trials to evaluate whether the S-ICD really is as good or better than devices that course wires into the heart, he said.

"If it is as safe and effective, then, great, we have another option to use," Hauser said. "But this thing just hasn't been adequately evaluated."

For one thing, the S-ICD provides a limited therapy -- it restarts a heart and prevents sudden cardiac death. It does not do the additional things -- such as pacing -- that transvenous ICDs provide. In some cases, Hauser said, such pacing therapy may actually prevent dangerous fibrillation and prevent a painful shock from having to be delivered.

In that way, Hauser said, the device is probably not a good option for everyone.

Stein said that Boston Scientific shares the belief that some patients should not get the device. "The big unanswered question is where in that broad middle ground will this be?" he said. "We don't know; time will tell."

On Wednesday, senior analyst Larry Biegelsen of Wells Fargo, in a note to investors, highlighted Hauser's concerns, adding: "This is consistent with our view that the first generation S-ICD is likely to be a niche product, but that future iterations could be more widely adopted."

Hauser, Biegelsen and Stein all seem to agree that doctors and patients are expected to move slowly when it comes to embracing the new device.

Biegelsen wrote that the S-ICD could eventually grab about 14 percent of the total worldwide ICD market, although "penetration will be low due to limitations of the first-generation device." He estimated worldwide sales of $46 million in 2013.