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American Heart Association acknowledges the
power of Heart Scans to predict heart attacks!
After years of political battling and resistance to CT
scanning for coronary calcium scoring, the American Heart Association
(AHA) has finally released a formal position paper acknowledging the
ability of heart scans to predict heart attacks.1
"The majority of published studies have reported that the total
amount of coronary calcium (usually expressed as the 'Agatston score')
predicts coronary disease events beyond standard risk factors
[emphasis ours]. . . These studies demonstrate that coronary artery
calcified plaque is both independent of and incremental with
respect to traditional risk factors in the prediction of cardiac
events."
In essence, the AHA finally agrees that CT heart scans
provide information about risk for heart disease that is not revealed by
conventional cholesterol testing or other risk predictors. It doesn’t
seem like a lot, but that statement alone has been the spark for many
heated debates and would never have been included in any official AHA
release before now.
UCLA cardiologist, Dr. Matt Budoff, is lead author of the position paper
and a long-time advocate of CT heart scanning. Notably, Dr. Budoff has
been a pioneer and champion of the original EBT scanners. He was also
the principal author of the controversial statement paper on CT heart
scanning slated for release in 2004, but blocked by the AHA, ostensibly
because the media had obtained premature warning of its release.
Because it represents an “official” position statement for the AHA, Dr.
Budoff and panel members admittedly wrote the document conservatively.
"Asymptomatic persons should be assessed for their cardiovascular risk
with such tools as the Framingham Risk Score. Individuals found to be at
low risk (<10% 10-year risk) or at high risk (>20% 10-year risk) do not
benefit from coronary calcium assessment." Much like the suppressed 2004
position statement, the 2006 guidelines focus on the application of
coronary calcium scoring on the so-called “intermediate-risk” person,
i.e., a risk of heart attack or other cardiovascular event of 10–20%
over a 10-year period. Many authorities, however, have stated that
intermediate-risk should be redefined as 6–20% 10-year risk.
There is actually nothing new in the position statement. It simply
collects and reports the “consensus” that has been reached by the
thousands of scientific publications that have brought CT heart scanning
to the forefront of cardiac risk determination. It does serve as an
in-depth summary for the cardiology community and lends an air of
“legitimacy” to a technology that has encountered resistance ever since
its introduction in the 1980s.
Should the AHA position statement affect your decision-making about CT
heart scanning? We don’t think so. If you’ve been following the Track
Your Plaque concepts, the AHA statement will tell you nothing new. Don’t
be confused by the low-,intermediate-, and high-risk distinctions made
in the statement. These are concessions made to the political powers in
the AHA who continue to resist the idea that imaging like CT heart
scanning is vastly superior to risk predictors like cholesterol or the
Framingham risk equation. We continue to advocate use of CT heart scans
in any male 40 years of age or older, females 50 years and older, but
starting at younger ages if any high-risk feature is present in your
history (e.g., heart disease in young family members, substantial
smoking history, diabetes, severe lipid or lipoprotein disorders).
The AHA statement does, without a doubt, represent a big step forward in
broadcasting the application of CT heart scanning to the public. Your
neighborhood physician is also more likely to consider ordering heart
scans for his patients, provide less resistance when a patient requests
one, and may even perhaps learn what to do with the results!
Editor’s Note
Perhaps the growing acceptance of heart scanning across
the U.S. forced the AHA into releasing its guidelines. No doubt, the
political pressure of major scan manufacturers General Electric,
Siemens, Toshiba, and Philips—all industrial powerhouses with $10’s of
billions in revenues—was also part of the motivation. In past, when the
only scan device was the EBT scanner manufactured by little Imatron
Inc., such pressure was not possible. But General Electric purchased
Imatron several years ago and then promptly scuttled the EBT scanner
and, in essence, consolidated the political pressure they could exert to
support the multi-detector scan technology. (Many EBT scanners are still
in operation and perfectly up to the job; GE will simply not continue to
manufacture any new EBT devices.)
What does this mean for the Track Your Plaque program? It could mean
that, sometime in future, insurance coverage may become a reality for CT
heart scanning. AHA endorsement is something insurance companies have a
difficult time dodging. Up until now, insurance companies have fudged by
saying that no official statement was available. That’s now all changed.
The AHA statement does mention the use of repeat coronary calcium
scoring (i.e. the basis for the Track Your Plaque program), though they
hedge by saying not enough scientific data is available. “Continued
progression of CACP [coronary artery calcified plaque] appears to be an
independent risk factor for future events, but future studies are
needed.”
It’s taken the AHA statement years to reach broad consensus on the use
of a single scan. I suspect it will be another several years before they
endorse the idea of serial scanning to track disease.
Circulation editor-in-chief, Dr. Joseph Loscalzo, was the man who
single-handedly withheld publication of the original 2004 guidelines on
coronary CT scanning, ostensibly because of a leak of the guideline
details to the media. (A story was published in the Wall Street Journal
about the forthcoming guidelines just weeks before their anticipated
release, prompting Dr. Loscalzo’s decision.)
In my mind, the responsibility should have been to publish the
guidelines despite the leak—perhaps even more so in an effort to clarify
what was partially misreported by the Wall Street Journal. In fact, Dr.
Loscalzo’s delay in publication for over two years I believe has been
responsible for the death or disability of tens of thousands of
Americans who may have otherwise been made aware of the value of CT
heart scans had the original guidelines been published.
Dr. Loscalzo stated “Circulation is concerned about the sanctity of
embargoed information to be published in the journal and the importance
of not releasing embargoed information until the article is ready to be
published. When individuals provide information to the media in advance
of statement publication, there is risk that the individuals’
perspective on an issue may influence the coverage of that issue and may
not accurately reflect the synthesized message intended by the
statement.”
Does that make sense to you? If there was indeed a leak, track down
where and who it came from. Don’t punish the public by denying them a
statement that could dramatically influence access (via insurance
reimbursement) and justify the use of heart scans to physicians who
remain uncertain or undecided about the role of this technology.
It’s worked out in the end, but I fear that political maneuvering by
people like Dr. Loscalzo, for noble reasons or not, delayed the broader
acceptance of a technology that had a rational scientific basis for use
years earlier. Likewise, I am simply unwilling to wait for “official”
endorsement for serial scanning like that advocated by Track Your
Plaque, an approach that has proven, in my experience, to be the single,
most powerful means to track, and potentially reduce, coronary plaque. A
burning fuse can only burn so long before the bomb explodes. You can
literally die waiting for consensus seekers to decide that they’re happy
with the weight of evidence.
References:
Budoff MJ, Achenbach S, Blumenthal RS et al. Assessment of coronary
artery disase by cardiac computed tomography: a scientific statement
from the American Heart Association Committee on Cardiovascular Imaging
and Intervention, Council on Cardiovascular Radiology and Intervention,
and Committee on Cardiac Imaging, Council on Clinical Cardiology.
Circulation 2006;114:000–000 [e-publication]
Copyright 2006, Track Your Plaque.
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