Interview with Harvey S. Hecht, MD, FACC (Part 1) -- Imaging & Diagnosis Center

Harvey S. Hecht, MD, FACC, is an internationally recognized expert in cardiac imaging and preventive cardiology, and is the author of more than 100 publications in peer reviewed journals. After achieving acclaim as a leader in the fields of nuclear cardiology and stress echocardiography, Dr. Hecht pioneered the development of noninvasive coronary computed tomographic angiography (CTA) and is a driving force behind CTA guided percutaneous coronary intervention and the relationship between CTA and intravascular ultrasound (IVUS). He was the first to demonstrate the poor relationship between risk factors and atherosclerosis.

Prior to his current position as Director of Cardiovascular Computed Tomography at Lenox Hill Heart and Vascular Institute of New York, Dr. Hecht held numerous faculty, clinical and administrative positions at institutions ranging from UCLA, USC, UCSF and Albert Einstein College of Medicine to the San Francisco Heart Institute, Arizona Heart Institute, Princeton Longevity Center, and Beth Israel Medical Center. Dr. Hecht is a Fellow of the American College of Cardiology and member of numerous professional societies, as well as a founding member of the SCCT.

Harvey S. Hecht, MD, FACC
Lenox Hill Heart and Vascular Institute of New York

Angioplasty.Org recently sat down with Dr Hecht to discuss a range of topics, from reimbursement issues to how he feels CTA will change the diagnostic paradigm for patients with suspected coronary artery disease.

Q: Last year Medicare announced plans to stop reimbursement almost entirely for computed tomographic angiography (CTA) and then earlier this month reversed itself.
Dr. Hecht: The initial denial of reimbursement by Medicare was absolutely insane. It was based upon their conclusion that there were not adequate data to support this utility, which was simply not the case. In reaching their decision, they ignored almost all of the recent articles that have been published, most of them over the last two years. So they did not do their due diligence in deciding that the data were inadequate. That's the first point.

Share This Story:

The second point is they said that there was no evidence that CTA improved patient outcomes. This was a totally hypocritical, double-standard stance on their part because that kind of evidence has never been provided for any cardiology technology. It has never been provided for echocardiography, for nuclear stress testing, for cardiac catheterization, for electrocardiography. The kind of trials that the critics have been asking for, involving randomized controlled trials, in which one group of patients gets the test and another group of patients doesn't get the test, in order to demonstrate that the use of the test improves outcomes -- that has never, ever been applied to any technology that we use. They were just using that as an excuse in the name of academic righteousness, which is to demand a randomized controlled trial for everything. They were using that to delay implementation of this technology which is the best thing that has happened to cardiology in the past decade.

Q: Why do you consider CTA to be so revolutionary?
Dr. Hecht: It is a breakthrough because, from the perspective of the interventionalist, it combines the best of invasive angiography with intravascular ultrasound (IVUS). There are multiple areas in which it proves to be a wonderful technology.

64-slice CTA image of a coronary artery
courtest Toshiba America Medical Systems

The first is that it will ultimately take its place as the first test in the evaluation of a cardiac patient, as opposed to stress testing. There is a general consensus, even among cardiologists, that in the low and intermediate risk patients, CTA is more effective than stress testing. It has a higher sensitivity and specificity, and it's particularly helpful in those areas where nuclear cardiology is at its weakest, which is to diagnose left main and triple vessel disease.

Nuclear stress testing underestimates the degree of the disease in 15% of left main and in 40% of triple vessel disease patients. And these are precisely the kinds of patients who you most do not want to miss.

The second issue is that when you do a CTA, in general in patients who do not have established heart disease, you also do a calcium score, obtained from a non-contrast CTA, which is the best prognostic tool for cardiac outcome that we have available to us. And that's been around for approximately 15 years, and unequivocally is far superior to anything, particularly the Framingham risk score, for your evaluation of the patient's cardiac risk. There's an enormous amount of data from tens of thousands of patients, and most recently the MESA study results are beginning to emerge, which show exactly the same thing: that a coronary calcium score is far and away independently the most powerful prognosticator of cardiac outcome in the asymptomatic population.

Had the Medicare ruling stood, it would have marked the death knell of coronary calcium. Because nobody pays for coronary calcium scoring right now except, I think, California. And coronary calcium scoring would have probably very likely been trashed along with CTA. And at this point, the absence of reimbursement for coronary calcium screening to me is unconscionable. We have a tool now that can identify the pool of patients out of which 95% of the myocardial infarctions will emerge, and we're not using it.

Q: Coronary calcium scoring is a major part of the recent SHAPE guidelines that you were one of the authors of.
Dr. Hecht: The SHAPE guidelines are perfectly appropriate. They are an attempt to introduce the best screening tool for coronary disease, i.e. coronary calcium, into the mainstream, and to use it much as we would use mammography.

So, the SHAPE guidelines in essence say that, except for the very lowest risk patients, men from 55 to 75 and women 45 to 75 should have a coronary calcium score as the initial risk evaluator, rather than looking at a Framingham risk score, because it's much more powerful than the Framingham risk score.

The nay-sayers still harp on, “There is no data showing us that patients who have a coronary calcium score do better than those who don't have a coronary calcium score”, and the response to that is exactly the same as we talked about with CTA. There's no data that the Framingham risk score has any effect on outcomes! And it's very clear that CTA is better than the Framingham risk score, so why not use the test that's better? It's incredibly straightforward. And I think it's a lapse on the part of the medical establishment to not have adopted it by this time.

Every year there are 500,000 MIs [heart attacks] as the first symptom of heart disease, 150,000 of which are fatal. Coronary calcium can identify the pool of high risk patients out of which 95% will emerge. Just by putting those patients on a statin, you've reduced events by 30%. Add a drug to improve HDL and triglycerides, you get much more of a decrease in events. Appropriate cost-effective analysis shows that it is the most cost-effective method, because the cost of a coronary calcium score will become that of a mammogram. A big objection has been, “Well, it’s expensive.” Well, mammography was expensive when it first came out, and now it's less than $100, and it will be the same with coronary calcium. People have to look upon heart disease with the same respect and attention that we do with breast cancer. Every year, every woman over 45 gets a mammogram for a disease that kills about 45,000 women every year. Heart disease kills 500,000 women every year, and they are simply not screened for it. Why not? And of course the argument applies to men as well. And in the future, once coronary calcium does become like mammography, people will say “Look at all the lives we wasted by not doing it earlier”.

Q: So how can this change occur?
Dr. Hecht: Reimbursement would change it overnight.

Q: Other criticism leveled at CTA is the amount of radiation exposure. For example, there was a recent study published in the New England Journal of Medicine that was done at Columbia.
Dr. Hecht: The Columbia study has been heavily faulted; it’s all extrapolation based upon theoretical data. Nobody takes radiation lightly. So we in the CT community are very concerned about it, of course. But everything has a risk-benefit ratio. Currently, the radiation dose is at worst equal to, at best better than, the typical nuclear stress test and, up until CT came along, nuclear cardiologists blithely did nuclear stress testing without being aware of what the radiation hazards were. So CTA is certainly no worse than nuclear stress testing on that account, and in addition all of the manufacturers now are providing programs, new acquisition methods, which will dramatically decrease the radiation exposure from its current level at about 8-14 millisieverts to hopefully 2-4 millisieverts.

Q: What are these new methods to reduce radiation exposure?
Dr. Hecht: They’re really software methods, protocol methods. The study is acquired during a limited part of the cardiac cycle, so that the radiation exposure, rather than being administered throughout the cardiac cycle, is restricted to a relatively small percentage of the cardiac cycle. So the actual radiation dose is dramatically decreased. That's for the CTA part of it. For the calcium score part, the radiation dose has always been lower -- about 1 millisievert.

Q: Another concern expressed by Medicare and critics of CTA is that it will lead to a slew of unnecessary tests.
Dr. Hecht: It's very clear to anybody who has been using CTA that, rather than increase additional testing and increasing cost, it has just the opposite effect. It is such a powerful tool that it will virtually eliminate, not totally, but substantially decrease the number of normal angiograms that are done in this country.

On a nationwide basis, if you look at the ACC National Cardiac Data Registry (NCDR), 37% of the caths done in stable patients show no significant disease, and these tests could have been avoided had there been a better triage to get into the cath lab. The problem is that the stress testing has been the gatekeeper, and there are many false positives with stress testing. The experience of anybody who's been involved with CTA is that the number of normal caths in their institution plummets. So from the insurance company and the national health economic perspective, you will have a dramatic decrease in costs that were allocated for unnecessary reasons: there was no disease found, in addition to the associated morbidity and mortality, however small, that's associated with an invasive angiogram.

Q: The risk of stroke or death during an invasive cath is very small, but the rate of bleeding complications at the access site, nerve trauma and so on is 3-4%, some say more.
Dr. Hecht: Exactly. So the ultimate outcome with CTA is that the catheterization lab is no longer going to be a diagnostic suite, it will be an interventional suite, which will be a much more efficient use of resources.

Q: Won’t this development negatively affect interventional cardiologists?
Dr. Hecht: No, I don't think it will, because CTA, by virtue of its IVUS qualities, which we have written about extensively, will provide a more accurate assessment of disease than conventional invasive angiography which visualizes only the artery lumen, not the wall, which is limited in the number of acquisitions and therefore does not do justice to imaging a stenosis at its worst narrowing, simply because of an insufficient sampling error.

And we all know that intravascular ultrasound (IVUS) tells a very different story than the luminography that we get in the cath lab. You can have diffusely narrow segments which appear totally normal on an angiogram because there's no focal narrowing: the whole segment is narrowed. You see that very easily on intravascular ultrasound. CTA also has those capabilities, so it will more accurately uncover those patients who need to have a procedure.

Q: Would the use of CTA impact the use of IVUS. For example if you see an atypical type of lesion on the CTA, would you then use IVUS in the cath lab to guide the balloon or stent for this patient?
Dr. Hecht: Correct. The paradigm is going to be that you do the CTA, and if the CTA shows less than 50% stenosis, then the patient goes to medical treatment. If it shows a very severe stenosis, greater than 75%, then the patient goes directly to the cath lab.

In the intermediate range, the 50 to 75% stenosis and those that meet the IVUS criteria that we apply to CTA, which is less than 4mm2 for the proximal vessels, and less than 6mm2 for the left main, they are then candidates for either a stress test to determine the functional significance of those or, if one is not happy with stress testing in the particular situation, they can go straight to the cath lab, and if the angiogram confirms the severity of the disease that is shown on the CTA, then they can have a procedure, assuming that the clinical situation is appropriate.

But if there is a disconnect, if the disease is angiographically inapparent, but was present on the CTA, then either IVUS or FFR is mandated to use as the gold standard for what is really going on in that vessel. So, it will be a change in the paradigm.

(Continue to Part Two)

This interview was conducted in March 2008 by Burt Cohen of Angioplasty.Org.