Tuesday, July 11, 2006

Problems With Broad Coronary Calcium Screening?

I read with interest a Forbes article from yesterday advocating large scale screening all males ≥45years and females ≥55years, except those defined as very-low-risk, with coronary calcium scanning or carotid ultrasound to detect subclinical atherosclerosis that was introduced by a relative newcomer to the heart disease prevention scene - the Association of the Eradication of Heart Attack. Their program is called the "SHAPE" initiative - "Screening for Heart Attack Prevention and Education." The article quoted was this on from the American Journal of Cardiology and represents work by some of the best and brightest in the field. Even Valentin Fuster, MD said of the SHAPE intiative:

It is a pleasure to forward this editorial note on the SHAPE Task Force report. The contributors to the SHAPE initiative must be congratulated for their original, ambitious, and provocative approach to the number one problem in the cardiovascular field, affecting millions of lives annually.
Provocative, indeed. A very polite critique was offered on this screening approach by Daniel DeNoon of WebMD with inciteful commentary by Eric J. Topol, MD. It is important to realize that calcium scoring has been controversial in cardiology because it uses forms of CT scanning that expose patients to high doses of radiation (average 82 mrem for men and a whopping 150 mrem for women - for comparison a 2-view chest x-ray is about 10 mrem and a 2 view mamogram is about 35 mrem), and have been marketed directly to the patient-consumer without federal support (i.e., Medicare reimbursement) for its clinical utility, and hence has been viewed by many as a technology to line certain imaging physicians' pockets. Could a financial incentive be happening with the latest initiative?

First of all, the Association of the Eradication of Heart Attacks (AEHA.org) was founded by Morteza Naghavi, MD, of the Texas Heart Institute (and carries its official address as 2472 Bolsover Dr, Suite 439, Houston, TX) which also happens to be nearly the same address as Endothelix, Inc. - with its official address of 2472 Bolsover Dr, Suite 439C, Houston, TX - which Mr. Naghavi also founded and owns shares in as well. Endothelix specializes in Digital Thermal Monitoring technology for the early diagnosis of "vulnerable plaque" in coronary disease. Interestingly, Dr. Naghavi's "Association" also seems interested in promoting intravascular ultrasound as a screening tool for carotid plaque and owns shares of Volcano Corporation - that happens to have a member of its board (S. Ward Casscells, MD) from the Texas Heart Institute where Dr. Naghavi works. Dr. Naghavi also has a number of patents in this area of calcium scoring. Now, given all this that I could find on the internet - are we really ready to advise this screening without prospective, randomized trials of its safety or efficacy (especially in terms of long-term cancer risk to our patients)? Or are we willing to repeat a scenario similar to the one we saw recently here in Chicago when doctors with financial interests in ultrafiltration for heart failure were recommending this therapy for their patients or the scenario reported regarding the financial ties between the Cleveland Clinic and Atricure?

Now don't get me wrong - I appreciate the doctors' willingness to disclose their ties to the companies involved. But before we adopt such broad, sweeping recommendations and make them part of policy recommendations that affect the entire US population, we must remove all potential financial conflicts of interests from the recommending body, have a better understanding of the real outcomes and costs imposed when a scan or ultrasound is found to be "positive," and be damn sure the side effects of such scanning (in terms of life-time carcinogenesis) doesn't create new public health problems (analogous to the days when radiation was used to treat acne).

--Wes

2 comments:

Anonymous said...

You seem to be suggesting that other entities, such as the American Heart Association and/or the American College of Cardiology, which typically recommend guidelines (and that's all any guideline is -- a recommendation) do not have financial relationships with pharmaceutical companies. That, of course, is ridiculous. Together, those two organizations receive tens of millions of dollars annually from pharmaceutical companies. And thank goodness! That money fuels much of the good works that are making an enormous difference in the battle against heart disease. However, to suggest that a $50,000 one-time grant somehow compromises the SHAPE Task Force -- an group of esteemed cardiologists and researchers -- and casts doubt on its recommendations is extremely insulting and wrong.

DrWes said...

Anony-
While I am in TOTAL agreement that the AHA and ACC receive lots of money from pharmaceutical companies, the conflicts of interests that I disclose on this post were not disclosed to the casual reader, and in my view, I felt they should have been. I am in no way discrediting the expertise of the individuals who make these recommendations, but to have such sweeping "guidelines" that stand to financially benefit those who recommend them and have potential downsides (like the risk of radiation - 64 slice CT scans have WAY more radiation than those I mention for EBCT), should be part of public record and clearly disclosed and peer-reviewed. Eric Topol, MD, another esteemed cardiologist whom I reference, had similar concerns.