By Debra Sherman
CHICAGO Jan 2 Boston Scientific Corp's
new leadless implantable heart defibrillator, hailed by some as
a breakthrough, should be used on a limited basis until more
data are collected, a prominent cardiologist wrote in an
editorial of a top medical journal.
Leads, or wires that carry electrical pulses from the
defibrillator - which is implanted in the chest - to the heart
have always been the weak link in these systems, used to treat
irregular heart beats. All of the device makers have had
problems at one time or another with leads.
Boston Scientific bought the leadless technology, known as a
subcutaneous implantable cardioverter-defibrillator, or S-ICD,
when it acquired Cameron Health last year. The Cameron device
was approved by the U.S. Food and Drug Administration in the
"The S-ICD has not yet been shown to be safe and effective
in a diverse patient population," Robert Hauser wrote in the
January issue of the Journal of the American College of
Hauser, of the Minneapolis Heart Institute, who has been a
vocal critic of medical device companies, also noted that the
leadless ICD has not even been shown to be as good as the
traditional ICDs that use leads.
He said the technology is a promising one that could fill
important gaps, especially by bringing it to countries where
facilities to implant traditional devices is not available, but
more data are needed first.
"Unless critical questions with regard to safety and
efficacy in primary and secondary prevention are addressed, the
S-ICD should be confined to certain subgroups," he said.
Dr. Ken Stein, Boston Scientific's Chief Medical Officer for
Cardiac Rhythm Management, said there was more in Hauser's
editorial that he agreed with than disagreed with.
"But it was approved by the FDA as being safe and
effective," he noted in a telephone interview. "It's an
alternative for physicians to consider. We agree there are
absolutely some patient populations that shouldn't get it," he
For example, patients who have a slow heartbeat or
uncoordinated pumping function should not get it because the
S-ICD cannot pace a slow heart beat or resynchronize
contractions of the heart's ventricles. On the other hand, the
S-ICD may be a better choice for patients who are at risk for
sepsis, a severe blood infection.
"For some patient populations, this is the best option,"
Stein said. "Somewhere in that middle ground is where the line
should be drawn."
Stein said the company is currently running clinical trials
and registers that will render more data, some of which will be
presented in the spring at the Heart Rhythm Society meeting.
Wells Fargo analyst Larry Biegelsen called the S-ICD
technology "transformational" but said this first generation
device is likely to be a niche product.
"We estimate the eligible S-ICD opportunity is currently
about 14 percent of the total worldwide ICD market, but estimate
penetration will be low due to limitations of the first
generation device," he wrote in a research note.
Biegelsen estimated worldwide sales of the S-ICD device to
be $46 million in 2013. Boston Scientific had sales of $5.4
billion in the first nine months of 2012.