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ANAHEIM, Calif. -- In clinics and doctors' offices of the
future, small handheld echocardiography machines will be used
to quickly screen patients' hearts for structural abnormalities
that could indicate the need for more detailed and thorough
cardiac testing. The stethoscope, currently the ubiquitous
symbol of the medical profession, will no longer be used in the
initial assessment of a patient's heart.

That's how cardiologist Dr. John Alexander sees the
potential of the latest advances in echocardiography technology
and miniaturization, based on the results of his new study at
Duke University Medical Center. While the new, smaller machines
do not provide the same level of detail as their larger and
more expensive counterparts, it appears they can detect heart
abnormalities needing further attention, even when used by
physicians with just minimal training.

"These handheld devices are not as good as standard
echocardiography for everything, but as a screening tool, they
are a major step forward over what we currently use," Alexander
said. "As a practical matter, they could pick up a large number
of patients who have heart abnormalities that cannot be
detected by a stethoscope or who have heart disease but are not
yet having symptoms."

Alexander prepared the results of his study for presentation
during the 74th annual scientific sessions of the American
Heart Association.

For years, cardiologists have recommended that patients with
suspected heart disease undergo hourlong standard
echocardiography exams, which, like ultrasound exams of babies
in utero, use sound waves to provide moving pictures of the
heart. These machines cost hundreds of thousands of dollars,
the technicians require years of training to operate them and
physicians undergo years of experience to interpret the
images.

In the past few years, however, miniaturization has reduced
these echocardiography systems to the size of a laptop
computer. While cardiologists have been debating the proper
role of these new devices and their accuracy, Alexander asked a
different question.

"We didn't want to know whether or not the new echo machines
are better than standard echo machines, but whether the new
machines could provide useful information when used during a
routine physical exam by someone with minimal training," he
said.

For their study, the Duke researchers recruited Duke
second-year medical residents and cardiology fellows who had no
prior experience with echocardiography and gave them three
hours of point-of-care echo (POCE) training. They were then
asked to perform POCE exams on patients who had just undergone
or were about to undergo a standard echocardiography exam. A
total of 533 patients were enrolled and the average POCE
examination took a little more than eight minutes.

The researchers then compared the results of the POCE
studies to the standard echocardiography findings on four major
heart abnormalities: left ventricular ejection fraction (the
strength of the heart's major pumping chamber); pericardial
effusion (fluid in the sac surrounding the heart); mitral
regurgitation (leaking of one of the major heart valves); and
aortic valvular thickening (thickening of another major heart
valve). The results were most positive with the first two
abnormalities.

"We found that clinicians with limited echocardiography
training can use POCE to reasonably detect left ventricular
dysfunction and pericardial effusion," Alexander said. "Low
ejection fraction is an incredibly important indicator of heart
health. For patients who might come to their doctor with
shortness of breath, a quick POCE could determine if there was
indeed a low ejection fraction. A stethoscope cannot reliably
detect these abnormalities."

Screening is especially important for older patients, many
of whom have reduced ejection fraction but do not yet have
symptoms that would get them referred for a standard
echocardiogram, Alexander said.

While POCE with minimal training was not as accurate in
detecting mitral regurgitation or thickening of the aortic
valve, Alexander did say that this would improve with
additional training.

"POCE shouldn't be seen as a replacement for standard
echocardiography, which will always have its place in answering
important questions about the heart," Alexander. "As a
screening tool, however, POCE could play an important role in
quickly determining which patients should be sent on for
further echocardiography testing.

"In reality, for most patients the only screening test is
their personal physician using a stethoscope," Alexander
continued. "This study shows that with minimal training, any
physician can use POCE to screen for heart problems."

While the new devices cost about $10,000, Alexander believes
that as their systems become more accepted by the medical
profession, the price will come down, making it feasible for
them to be used routinely in doctor's offices, clinics,
emergency rooms and hospital units.

Alexander's team included the following colleagues from the
Duke Clinical Research Institute (DCRI): Dr. Eric Peterson,
Anita Chen, Tina Harding, David Adams and Dr. Joseph Kisslo.
The study was funded by the DCRI.

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