Cardiac CT Angiography - Coming to a You Via Modern Medicine

Contrast-enhanced cardiac computed tomographic angiography, and often shortened to
several names including CCTA, CTA, and CCT. And also loosely referenced by the terms calcium scoring, or spiral, helical, electron beam, or Ultrafast CT.

These are tests done by cool new CAT scan-like machines, an example from GE Healthcare is here: http://www.gehealthcare.com/usen/xr/int/products/vascular.html
They can x-ray fast enough to eliminate the blur that would otherwise be caused by the movement of a beating heart. Inject into the blood some radio-opaque isotope with an affinity for calcium, and the disease state of coronary arteries can be visualized.

Think of the possible applications in health care! For example, diagnose chest pain in the emergency room, eliminate risky and expensive cardiac catheter angiography, no more worry and wait for those with CAD risk factors or vague symptoms.

However, there are questions about how precise results really are, when this testing should be done, and how meaningful testing becomes in influencing the treatment / prevention / outcomes of disease.

When we allow science to answer these questions through randomized clinical trials, it's called EBM.

Despite the apparent lack of substantial published credibility, some hospitals have been doing variations of CTA for years. They used established standards for billing Medicare and insurance. On claims, they used existing AMA CPT coding that describe CT imaging of the vessels in the chest cavity.

With newer, better ($1.7 mil) machines, and an associated greater technical expertise to "score" the smaller coronary vessels, hospitals and doctors began to demand more reimbursement than they could expect for the commonplace CT scan. The AMA considered creating new procedure codes in Summer 2005, and ended up assigning temporary codes to the cardiac CT scan procedures. By assigning the temporary codes to CTA beginning in 2006, the AMA considers the scans an "emerging technology."

So far, notice that the new machines and the new CT exams just kind-of evolved from standard scanning for specific (almost rare) indications, into highly technical radio-isotope scans with broad applications.

It's fun to speculate which laws of economics are applying here. The machine manufacturers might have known the Medicare-based payment for a CT scan wasn't likely to go up much, so a few new broad indications or ways to use CT scans becomes the key to raise sales. The doctor and radiologist need special training to "score" or interpret the new tests and to operate the new scanning equipment. Since it's more complicated, it's fair that they get comparatively more payment than they did for the old standard CT scans.

The trouble that happened is, the new AMA CPT temporary codes used for CTA aren't assigned a payment by Medicare. And, per CPT and Medicare rules, the new codes must be used on claims nevertheless. Suddenly in 2006, insurance companies started to get claims with these codes, and many didn't have a process to pay on them. Which, of course, led to them to ask, should they pay on them?

Hospitals and doctors began demanding a specific payment for the higher-tech CT scans from local Medicare Intermediaries. Six professional physician organizations including the American College of Radiology (ACR) and the American College of Cardiology (ACC) jointly published a draft coverage policy that Medicare Intermediaries, and private payors could adopt and endorse.
http://www.scai.org/pdf/FINAL%20Model%20LCD%20for%20CCT%20and%20CTCA.pdf#search=%22ccta%20acc%22
Some Medicare Part B payers adopted this model local coverage decision (LCD) and continue to pay for CTA.

Private insurance carriers have set their own path related to coverage of the new codes / new CT scan. Aetna, Cigna, and Humana are among bigger players who
all have published non -coverage policies for CTA. (Aetna example -
http://www.aetna.com/cpb/data/CPBA0228.html)

This month (August 2006) the BCBSA TEC reevaluated and reaffirmed that CTA had not met their scientific evidence-based technology evaluation criteria, and the technology remains experimental / investigational. http://www.bcbs.com/tec/tecinpress/8206.html
BCBSA TEC main results:
"Seven studies compared CTA to angiography for diagnosis of coronary artery stenosis, ranging in size from 30 to 84 patients. These studies enrolled essentially convenience samples of consecutive patients scheduled to undergo angiography, and thus may be subject to spectrum bias. No study specifically studied a lower-risk subset of those patients referred for angiography, which is the target population for this procedure."

Almost as if in response, the six fore-mentioned professional organizations will release a formal statement of science-based endorsement for CT angiography in the October 2006 issue of The American Journal of Radiology. The new policy outlines 8
specific indications where CT angiography will be indicated.

So there we have it. On one side, hospitals and doctors see the test as great way to understand cardiac health in any or all of their patients. Insurance companies see a test that everyone, to some extent, might benefit from, but the value of testing
has not been established.

Is CTA going to impact mortality or morbidity of CAD? Or will it become just another in the long stream of "risk stratification" tests, the results from which are nice to know, but they don't substantially impact real health outcomes in the huge majority of those who have it done?

I think the Hospitals and Doctors will trump the analytical EBM scientific reviews of the insurance companies. If so, will the application of CTA be too broad, will we do too many? What's the risk that they will be one more straw on the back of the runaway cost of medicine in our society? (All told, they are about $1,700 apiece.) Does the potential for good outweigh the risks, or offset the costs?

Since there is not the science or data for predictions, we'll just have to wait and see.

Nawledge