So why all the passion?There are a lot of equivocal screening tests used in cardiology, but none but the EBT have engendered TV and radio commercials imploring the public not to miss the opportunity to be screened. And few save the EBT have caused legions of opposing cardiologists to hasten to the airwaves to publicly deplore their use, or professional societies to rush position papers into print in an attempt to adjudicate the differences in opinion before the two sides come to blows.
To understand why the EBT of all cardiac screening tests is so controversial, one simply has to (to coin a phrase) follow the money. It costs about $2 million to buy the machine that does EBTs. Especially in todays health care environment, with hospitals and HMOs going bankrupt every day, thats a lot of money. Furthermore, most insurance companies, after reviewing the available data on EBTs (and noting the high proportion of false positive tests), have elected not to pay for the test. As a consequence, most hospitals have quite reasonably elected not to spend a huge wad of money to buy a device that performs (yet another) non-invasive cardiac screening test, one that is, to boot, non-reimbursable.
But look what the hospitals that have purchased EBTners have figured out: If you buy it (and invest in the appropriate advertising,) They Will Come. And furthermore, if you position it effectively (and nobody wants to miss their kids birthday,) They Will Pay Cash.
Think of it. Payment in advance, major cards accepted. No paperwork. No pre-certification. No wrangling 8 12 months to collect an average of 45% of the amount billed. The best thing that ever happened, many hospitals are finding, was when insurance companies refused to pay for the test. Suddenly, the EBTner was no longer bogged down within the traditional health care system; suddenly, it was in the wonderful, wild free market.
Theres more. Theres a Dirty Little Secret in cardiology that has to do with non-invasive tests. Every time a new non-invasive heart test is invented, it is hailed as bringing us one step closer to the day when invasive tests will no longer be necessary. And yet, as time goes by and the new non-invasive test comes into common use, more and more invasive tests end up being performed. This is not a mysterious or inexplicable result. It is entirely predictable.
And thats the Dirty Little Secret. To wit: every new non-invasive test creates a brand new category of false positive results that need to be followed up by performing an invasive test. Therefore, each time a new non-invasive test comes into use, the need to perform invasive procedures increases.
For EBTs, this truism applies in spades, because, as we have seen, a cutoff calcium score has been selected that guarantees a significant proportion of falsely positive tests.
So cardiologists lucky enough to work in hospitals that were early adopters of EBT scanners, and that advertised them sufficiently, found that their catheterization volume increased significantly. They learned to like the EBT very much, and found themselves willing to appear in commercials promoting this effective screening tool. Cardiologists in neighboring hospitals, feeling the impact of paying customers being siphoned off by (and being catheterized at) rival institutions, tended to react rather passionately and publicly themselves, but in the opposite direction.
The next thing you know, youve got a controversy on your hands.
Beyond the passionEarly adopters of the EBT, by blitzing the airwaves with commercials of dubious taste, tended to poison the waters for a sober, scientific assessment of the efficacy of this test as a screening tool. But as time has gone by, the publication of several scientific studies has tended to bring the discussions regarding the usefulness of the EBT to a somewhat higher plane.
In summary, these studies have shown what one might expect: the EBT is effective in identifying individuals who are likely to have significant coronary artery disease. And while it is often stressed that a normal EBT does not rule out the possibility of coronary artery disease (and so people with good EBT results should not take up smoking, eating, drinking, and being merry), by far the bigger problem is that almost half the patients with a positive scan turn out not to have significant coronary artery blockages.
Some have said that this latter problem is a blessing in disguise, since the presence of calcium on the coronary arteries is a powerful motivator for patients to adopt healthier lifestyles. The calcium means, after all, that they really do have coronary artery disease it just hasnt progressed enough to cause serious problems yet.