"Heart scans" are not always heart scans

18. July 2007 William Davis (6)
Beware of the media reports now being issued that warn that "CT heart scans" pose a risk for cancer.

One report can be viewed at
http://www.webmd.com/cancer/news/20070717/ct-heart-scan-radiation-cancer-risk.

This was triggered by a Columbia University study of risk for cancer based on the dose of radiation used in CT coronary angiograms. Theoretically, exposure to the radiation dose of CT coronary angiography can raise risk for cancer by 1 in 143 women if radiated in their 20s just from that single exposure.

If you've been following the Track Your Plaque discussion, as well as my diatribes in the Heart Scan Blog, you know that the media got it all wrong. The "heart scans" they are referring to are not the same as the heart scans that we discuss for the Track Your Plaque program.

A conventional heart scan (of the sort we refer to) exposes the recipient to 4 chest x-rays of radiation if an EBT device is used, around 8-10 chest x-rays of radiation if a 64-slice CT scanner is used. For the quality of information we obtain from these screening heart scans, we feel that it's an acceptable exposure.

The "heart scan" this study and subsequent reports refer to is not truly a screening heart scan, but a CT coronary angiogram, or CTA. CTAs are performed on the same CT or EBT devices, but involve far more radiation. CTA exposes the recipient to about 100 chest x-rays of radiation on a 64-slice device (more or less, depending on the way it is performed.) Just a couple of years ago, some centers were performing CTA on 16-slice devices, a practice I and the Track Your Plaque program vocally opposed, since up to 400 chest-rays of radiation were required! I even called a number of centers advising them that they were putting the public in jeopardy. CTAs also require injection of x-ray dye, just like any conventional angiogram.

CTA on 64-slice CT scanners require the same radiation exposure as a conventional heart catheterization, an issue glossed over in most conversations. In other words, the test that many of my colleageus so casually recommend poses a similar risk.

The message: the test I advocate for screening for coronary heart disease is a CT or EBT heart scan, not a CT coronary angiogram. CTA is a useful test and will get better and better as the engineers discover ways to reduce radiation exposure. But, in 2007, CTA is a diagnostic device, not a screening device. If you require an abdominal CT scan because your doctor suspects pancreatic cancer, or a CT scan of the brain because you might have a life-threatening aneurysm causing double-vision or seizures, it would be silly to not undergo the scan because of long-term and theoretical cancer risk.

But undergoing a CT coronary angiogram for screening purposes is ridiculous with present technology. I've said it before and I will say it--shout it--again:

CT coronary angiograms are not screening procedures; they are diagnostic procedures that should be taken seriously and do indeed pose measurable risk for cancer, a risk that is presently unacceptable for a screening test.

You wouldn't undergo a mammogram to screen for breast cancer if it exposed you to 100 chest x-rays of radiation, would you? Screening tests should be safe, reliable, accurate, and inexpensive. CT coronary angiography is none of these things. Genuine heart scans--the kind the Track Your Plaque program talks about and relies on--is all of those things.
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Comments (6) -

  • Anonymous

    7/19/2007 12:16:00 AM |

    Dr. Davis, would you please specify the millisievert values you are assuming for chest x-ray, EBCT Ca score, MSCT Ca score, and CT angiogram? I just got a 64-slice Ca score and they told me I received an effective dose of 2 mSv. Would a CT angiography typically result in 20 mSv?

  • Dr. Davis

    7/19/2007 12:59:00 AM |

    Hi,

    Please see my Blog post, CT scans and radiation exposure at http://heartscanblog.blogspot.com/2007/06/ct-scans-and-radiation-exposure.html

    You may notice some differences. There's enormous variation in exposure, depending on how it's measured, how the scan is performed, type and manufacturer of scanner. However, you can get a good idea of ballpark figures from the table in the blog post.

  • Dr. Davis

    7/19/2007 1:02:00 AM |

    Let me try that URL again:

    http://heartscanblog.blogspot.com/
    search/label/CT%20scans%20and%
    20radiation%20exposure

    Or, go to the left sidebar of Blog contents and see "CT scans and radiation"

  • JT

    7/22/2007 1:55:00 AM |

    I watch Fox news.  And with that statement I'm sure some are rolling their eyes.  Never before in the history of America has declaring what news channel one watches apparently pigeonholed one on their political views.  

    Like many I get my news from different locations: internet blogs, TV, radio, magazines, newspapers, etc, but in the morning I often watch Fox and Friends.  I do so for two reasons I suppose, the first being that I enjoy the joking around / humor on the set.  The second reason why I watch Fox is because it goes out of its way to present two sides of a debate.  It seems revolutionary what Fox has done to TV news - present two sides of a story.  Some people become terribly wound up over this.  On a personal note, I have an "ultra liberal" uncle, by his own definition, that in all honesty is so upset over Fox news and me watching it that he no longer communicates with me.  Uncle Gordon probably has never watched Fox News.  He only knows what he has heard.  And knowing him if he did watch he would only see the conservatives and not notice the liberal view point.  I hope one of these days he calms down and we can find ourselves on friendly terms again.  Change is hard for some to come to terms with.          

    When reading this blog, it disturbed me.  I wish that all news reporters tried harder to present two sides to a story. These high radiation reports would be easy to demonstrate as being only half true.  But instead, because of poorly researched, unprofessional reporting, there undoubtedly will be Americans that will decide to not have a life saving CT heart scan for fear of radiation poisoning.  And that is sad.

  • Dr. Davis

    7/22/2007 3:09:00 AM |

    Hi, JT--

    I couldn't agree more.

    If there's one theme that presents itself over and over lately, it is the struggle to discern the truth in the sea of information we're all presented with every day. I can only hope that we all zig-zag towards a real truth over time.

  • Darwin

    7/24/2007 6:34:00 PM |

    Re the CTCA - new study out concerning radiation exposure for young women.

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In heart disease prevention, shoot for perfection

12. April 2006 William Davis (0)
It really struck me today that it's the people who've chosen to compromise their prevention program who end up with trouble--heart procedures, heart attack, even heart failure.

Take Bob, for example. Bob is 73 years old and had a bypass operation in 2000. The procedure went well and Bob enjoyed 6 years of seemingly trouble-free life. Bob had a seriously low HDL cholesterol for which he as taken a modest dose of niacin, but was unwilling to do much more. His HDL cholesterol was thererefore "stalled" at around 40 mg. (We aim for 60 mg or greater.) We talked repeatedly about the options for increasing HDL but Bob was content with his results. After all, since his bypass operation, he'd felt well and could do all he wanted without physical limitation.

But Bob underwent a stress test for surveillance purposes (which we routinely do 5 or more years after bypass surgery). The test was markedly abnormal with two major areas of poor blood flow to his heart (signalling potential heart attack in future). Bob ended up getting 5 stents to salvage two bypass grafts, both of which showed signs of substantial degeneration.

I've seen this scenario repeatedly: A person is unwilling to go the extra mile to obtain perfection in lipid/lipoprotein patterns, lifestyle changes, and taking the basic, required supplements. Compromises eventually catch up to you in the form of another heart attack, more procedures, heart failure, physical disability, even death.

The message: Don't draw compromises in heart disease prevention. Coronary plaque is a chronic process. It will take advantage of you if you ever let your guard down.

The epidemic of small LDL

11. April 2006 William Davis (0)
Of the patients I saw in my office yesterday, virtually EVERYONE had small LDL.

Small LDL is emerging as an extraordinarily prevalent lipoprotein pattern that drives coronary plaque growth. Previous estimates have put small LDL as affecting only 20-30% of people with coronary disease. However, in my experience in the last few years, I would estimate that greater than 80% of people with measurable coronary plaque have small LDL.

If you have a heart scan score >zero, chances are you have it, too.

I call small LDL a "modern" disease because it has skyrocketed in prevalence recently because of the great surge in inactivity in Americans.

When's the last time you walked to the grocery store and back, lugging two bags of groceries? How many years has it been since you've push-mowed your lawn? All the small conveniences of life have permeated further and further into our activities. Most of us spend the great majority of our day right where you are now--on your duff.

On the bright side, small LDL in most people is reducable by simply getting up and going. But the old teaching of 30 minutes of activity per day is now outdated. This was true when the other hours of your life included physical activities, like housework or a moderately active job. However, if the other 23 1/2 hours of your day are sedentary, then 30 minutes a day won't do it. An hour or more of activity, whether exercise or physical labor of some variety will get you better small LDL-suppressing results.

For most people with small LDL, fish oil and niacin are also necessary to fully suppress small LDL to the Track Your Plaque goal of <10 mg/dl.

A great discussion on vitamin D

10. April 2006 William Davis (0)
If you need better convincing that vitamin D is among the most underappreciated but crucial vitamins for health, see Russell Martin's review of vitamin D and its role in cancer prevention. You'll find it in March, 2006 Life Extension Magazine or their www.LEF.org website at:

http://search.lef.org/cgi-src-bin/MsmGo.exe?grab_id=0&page_id=1308&query=vitamin%20d&hiword=VITAM%20VITAMER%20VITAMERS%20VITAMI%20VITAMINA%20VITAMINAS%20VITAMINC%20VITAMIND%20VITAMINE%20VITAMINEN%20VITAMINES%20VITAMINIC%20VITAMINK%20VITAMINS%20d%20vitamin%20

Our preliminary experience over the past year suggests that vitamin D may be the crucial missing link in many people's plaque control program. We've had a handful of people who, despite an otherwise perfect program (LDL<60, HDL>60, etc.; vigorous exercise, healthy food selection, etc.--I mean perfect)continued to show plaque growth. The rate of growth was slower than the natural expected rate of 30% per year, but still frightening rates of 14-18% per year--until we added vitamin D. All of a sudden, we saw dramatic regression of 7-25% in 6 months to a year.

This does not mean that vitamin D all by itself regresses plaque. I believe it means that vitamin D exerts a "permissive" effect, allowing all the other treatments (fish oil, LDL reduction, HDL raising, correction of small LDL, etc.) to exert their full benefit. So please don't stop everything and just take D. This will not work. However, adding vitamin D to your program on top of the basic Track Your Plaque approach--that's the best way I know of.

MSNBC Report: We need more heart procedures!

10. April 2006 William Davis (0)
A recent headline from MSNBC by Robert Bazell reads:

NEW YORK - Angioplasty, bypass surgery and cholesterol-lowering medications are among the many interventions that have brought a sharp decrease in heart disease deaths in recent years. But, as Dr. Sharon Hayes of the Mayo Clinic points out, there is one big problem.

“The death rates in women have not declined as much as they have in men,” she says.

The piece goes on to suggest that women are getting short-ended in the diagnosis of heart symptoms and heart attack. The solution: More testing to assess the need for procedures like bypass.

This is typical of the device and medication-dominated media consciousness: More procedures, more medication, more devices. Who's paying for advertising, after all? The money at stake is huge. But is this what you want?

Don't be swayed by media reporters with limited understanding of the real issues (at best), consciousness of who's paying for advertising (at worst). Yes, heart disese is often underestimated or misdiagnosed in women. The answer is better detection earlier in life followed by efforts to halt the process--effective, safe treatments for people's benefit, not just profit.

What role cholesterol medication?

10. April 2006 William Davis (0)
A frequent conversation point among my patients, as well as participants in the www.cureality.com program, is "Are cholesterol medications really necessary?"

No, they are not. What IS necessary is to correct all manifest and hidden causes of coronary plaque. Among these causes, in my view, is LDL cholesterol of 60 mg/dl or greater. There are many other causes of coronary plaque--e.g., small LDL particles, unrecognized hypertension, Lp(a), hidden diabetic patterns, etc.--but reducing LDL to 60 mg is still an important part of a plaque-reversing effort.

Insofar as we wish to get LDL to this goal, the statin cholesterol drugs like Lipitor, Zocor, Crestor, etc. may play a role. However, they should only be considered after a full effort dietary program is pursued. Don't follow the American Heart Association's diet unless you want to fail. It's nonsense.

For a more detailed discussion of how to use nutrition and nutritional supplements to reduce LDL cholesterol, go to www.lef.org, the website for the Life Extension Foundation. I wrote an article for their magazine called "Cholesterol and Statin Drugs: Separating Hype from Reality". You'll find the article at http://search.lef.org/cgi-src-bin/MsmGo.exe?grab_id=0&page_id=1295&query=davis%20cholesterol%20natural&hiword=CHOLESTEROLA%20CHOLESTEROLS%20DAVI%20DAVID%20DAVIE%20DAVIES%20DAVIN%20DAVIO%20DAVISON%20DAVISS%20DAVIT%20NATURALBASED%20NATURALES%20NATURALIZED%20NATURALLY%20NATURALS%20NATURE%20NATURES%20cholesterol%20davis%20natural%20.)

Can your plaque-reversal efforts succeed without statin drugs? It depends on your causes. For instance, someone with small LDL and Lp(a) only may do great on our basic program and then add niacin. Unfortunately, another person with a starting LDL cholesterol of 240 mg/dl--sky high--will have more success with these drugs.

Believe me, I am no blind supporter of drug companies and their flagrantly profit-seeking practices which, in my view, are cut-throat, shoving anyone and anything out of their way to increase profits and market share. I share many of Dr. Dave Warnarowski's views on how vicious their tactics can be; see his recent Blog post at http://www.drdavesbest.com/blog/ called "I smell a rat".

Nonetheless, the deep and well-funded research of the pharmaceutical industry does yield some useful tools. You don't have to love the insect exterminator, but if your house is being eaten by termites, his services can be useful. Same thing with these drugs. Useful--not the complete answer, not even close, but nonetheless useful in the right situations. Sometimes antibiotics are necessary, even life saving. That's how cholesterol drugs are, too.

Take it all in the proper perspective. Your goal is not cholesterol reduction, per se, but plaque control, preferably reversal.

Supplement Mania!

9. April 2006 William Davis (3)
Ever hear of "polypharmacy"? That's when someone takes too many medicines. People will have lists of 15-20 prescription medicines, for instance, with crazy interactions and oodles of side-effects.

Well, how about "poly-supplments"? That's when someone takes a large number of nutritional supplements.

Let me tell you about a 45 year old man I met.

In an effort to rid himself of risk for heart disease that he felt was likely shared with his family (brother and father diagnosed with heart attacks in their late 40s), Steve followed a program of nutritional supplementation. You name it, he took it: hawthorne, anti-oxidant mixtures, vitamins C, E, B-complex, saw palmetto, 7-keto DHEA, velvet deer antler, gingko biloba, policosanol, chronium picolinate, green tea, pine bark extract, St. John's Wort, CoEnzyme Q10, papain and other digestive enzymes...He became a distributor for a nutritional supplement company to allow him to afford his own extraordinary program.

To satisfy himself that he had indeed "cured" himself of heart disease, he got himself a CT heart scan. His score: 470, in th 99th percentile. Steve's heart attack risk based on this score was around 10% per year. High risk, no question.

For weeks after his scan, Steve admitted walking around in a daze, not knowing what to do. Years of telling himself that he had effectively dealt with his heart disease risk, now all down the drain.

When we met, I persuaded him that to think that this collection of supplements would reverse heart disease was magical thinking. We trimmed his list down to the essentials and got him on the right track.

Heart disease is controllable and reversible, but not this way. Don't fool yourself into thinking that some collection of supplements will be enough to stamp out your heart disease risk. Just like taking an antibiotic when you don't have an infection achieves nothing, so does taking the wrong supplements.

What does heart scanning mean to you?

8. April 2006 William Davis (0)
CT heart scans can mean different things to different people.


What does a heart scan mean to you? There are several possibilities:

1) A way of reducing uncertainty in your future.

2) A tool to crystallize your commitment to health.

3) A device to help you track how successful your heart disease prevention program is.

4) A trick to get you in the hospital.

5) A moneymaking tool for unscrupulous physicians hoping to profit from "downstream" testing, particularly heart catheterizations.


Like anything, heart scans can be used for both good and evil. How can you be sure that your heart scan is put to proper use--for your benefit and not someone else's profit?

Simple: Get educated. Understand the issues, be armed with informed questions.

If, for instance, you're a 55-year old female with a heart scan score of 90, active without symptoms, and you're told to have a heart catheterization right off the bat---run the other way. This is bad advice. A heart procedure like catheterization at this score in an asymptomatic woman is very rarely necessary. That decision can only be made after a step-by-step series of decisions are made by a truly interested, unbiased party. (A stress test is almost always required in this situation before the decision can be made to proceed with a catheterization.)

Unfortunately, in 2006, getting unbiased advice from your doctor is still a struggle. That's why we started Track Your Plaque---unbiased information, uncolored by drug or device company support, with an interest in the truth.

Coronary disease is drying up!

7. April 2006 William Davis (1)
I had an interesting conversation with a device representative this morning. He was a sales representative for a major medical manufacturer of stents, defibrillators, and other such devices for heart disease.

Since I'm still involved with hospital heart care and cardiac catheterization laboratories, this representative asked me if I was interested in getting involved with some of the new cardiac devices making it to market over the next year or two. "The coronary market is drying up, what with coated stents and such. We've got to find new profit sources."

Well, doesn't that sum it up? If you haven't already had this epiphany, here it is:

HEART DISEASE IS A PROFITABLE BUSINESS!

Why else can hospitals afford billboards, $10 million dollar annual ad campaigns, etc.? They do it for PROFIT. Likewise, device and drug manufacturers see the tremendous profit in heart disease.

The representative's comments about the market "drying up" simply means that the use of coated stents has cut back on the need for repeat procedures. It does NOT mean that coronary disease is on the way out. On the contrary, for the people and institutions who stand to profit from heart care, there's lots of opportunity.

Track Your Plaque is trying to battle this trend. Heart disease should NOT be profitable. For the vast majority of us, it is a preventable process, much like house fires and dental cavities.

Mammogram for your heart

6. April 2006 William Davis (0)
With the booming popularity of "64-slice CT scans", there's a lot of mis-information about what these tests provide.

These tests are essentially heart scans with added x-ray dye injected to see the insides of the arteries. However, to accomplish this, a large quantity of radiation is required. In addition, the test is not quantitative, that is, it is not a precise measure that can be repeated year after year.

It is okay to have a 64-slice CT coronary angiogram. It is NOT okay to have one every year. That's too much radiation. However, a heart scan can be repeated every year, if necessary, to track progression or regression. Once stabilization (zero change) or reduction is achieved, then you're done (unless your life takes a major change, like a 20 lb weight gain).

The tried-and-true CT heart scan is the gold standard--easy, inexpensive, precise, and repeatable. Not true for 64-slice angiograms.

Is your doctor using "leeches"?

4. April 2006 William Davis (0)
What if you went to your doctor for a problem and he/she promptly placed leeches on your body?

Yeccchhhh! Would you go back? I'd bet that you'd run the other way as fast as your bleeding legs could take you. Outdated health practices like "bleeding" are outdated for good reason.

Then why would you allow your doctor to approach your heart disease prevention program by checking cholesterol and then waiting for symptoms to appear? That miserable approach leads to tragedy and death all too often--ask Bill Clinton! He might as well have had leeches!

Don't allow your doctor's ignorance or disinterest impede your prevention program. Get your coronary plaque measured, then attack it from all sides by knowing all causes, hidden and obvious. That's why Track Your Plaque is such an effective program.

I often wonder why more doctors aren't using this unbelievably powerful approach to deal with heart disease. But when I see colleagues implanting stents, defibrillators, and the like for many thousands of dollars per patient, the answers are obvious. Given a choice of a rational, effective program of prevention that pays the doctor a few hundred dollars for his time, versus $2000 to $10,000 for a procedure, you can see that the temptation is irresistible for many physicians.