Beware the "false positive" stress test

There's a widely-known (among cardiologists) problem with nuclear stress tests. It's called the "false positive." (Nuclear stress tests are known as stress Cardiolites, stress thalliums, stress Myoviews, persantine stress tests, adenosine stress tests)

Stress tests, nuclear and otherwise, are helpful for identifying areas of poor blood flow. If an area of poor blood flow is detected and the area is substantial, then there may be greater risk of heart attack and other undesirable events in the relatively near future.

What "false positive" means is a stress test that shows an abnormality but it's not true--it is falsely abnormal. There are a number of reasons why this can happen. The problem is that this phenomenon is very common. Up to 20% of nuclear stress tests are false positives.

There are indeed situations where there may an abnormality and it is not clear whether it is true or false. This may lead to a justifiable heart catheterization or CT coronary angiogram. But, given the extraordinary number of false positives, there's a lot of gray in interpreting these tests. Hospital staff, in fact, call nuclear medicine "unclear" medicine. It's common knowledge that you can often see just about anything you want to see on a nuclear image of the heart. Abnormalities in the bottom of the heart, the "inferior" wall, are especially common due to the overlap of the diaphragm with the heart muscle, yielding the appearance of reduced blood flow. Defects in the front of the heart heart are common in females with large breasts for the same reasons.

The problem: The uncertainty inherent in nuclear stress tests opens the door to the unscrupulous or lazy practitioner. Any blip, tick, or imperfection on the nuclear images serve as carte blanche to drag you into the hospital for procedures.

This abusive practice is, in my experience, shockingly common for two reasons: 1) It pays better to do heart catheterizations, and 2) Defensive medicine.

What's the disincentive? Only doing the right thing and maintaining a clear conscience. Slim reasons for many of my colleagues--and a lot less money.

If you are without symptoms and feel fine, and a nuclear stress test is advised by your doctor, followed by a discussion of an abnormality, insist on a discussion of exactly what is abnormal, just how abnormal, and what the alternatives might be. If you receive unsatisfactory or incomplete answers despite your best effort, it's time for another opinion.

Don't neglect your magnesium

Magnesium is kind of boring. So most people don't pay too much attention to it.

Magnesium can be important, however. I saw an interesting phenomenon recently. A type I diabetic patient of mine (that is, an adult who developed diabetes as a child), Mitch, was experiencing wide swings in blood sugar: low low's and very high high's (300-400 mg/dl). Mitch's magnesium was only marginally low at 2.0 mEq/L. (Ranges for normal magnesium blood levels are usually 1.3–2.1 mEq/L or 0.65–1.05 mmol/L.) Note that Mitch's blood levels fall within "normal." I do not agree with these "normal" ranges. I shoot for 2.1 to 2.4 mEq/L, which I think is the truly normal range.

In addition to eating plenty of raw nuts and green vegetables, Mitch began supplementing magnesium with magnesium citrate, 200 mg twice a day (our preferred supplement form). He reported that the wide swings in blood sugar were nearly eliminated.

Mitch's dramatic benefit is just a great illustration of how magnesium can help control blood sugar metabolism. A type I diabetic is more sensitive to the effects, but anyone with type II (adult) diabetes, metabolic syndrome, or just a slightly high blood sugar could benefit from magnesium supplementation.

There's a number of ways to accomplish getting sufficient magnesium in your daily regimen. Track Your Plaque members, Be sure to read:


Your water may be killing you at
http://www.cureality.com/library/fl_03-002magnesium.asp

Magnesium: Water to the rescue! at http://www.cureality.com/library/fl_03-010magnesium2.asp

Third heart scan a charm

It struck me recently that, for many people, it's not the second but the third heart scan that more commonly shows a reduction in score.

I think this is because many people's reaction to their first heart scan is "This can't be. There's no way my arteries have that much plaque." They then follow a half-hearted program to correct their patterns.

When the second heart scan shows a significantly higher score, that really catches their attention. This is when they finally buckle down and give it their all.

Only the occasional person will, after the first heart scan, seize full control and take their program very seriously. These tend to be highly motivated people.

Don't feel too bad if your second heart scan score shows an increase. Look at it for what it represents: feedback on the adequacy of your program.

Metabolic syndrome--cured

Peter started out at age 59 at 248 lbs, standing 6 ft tall (BMI = 33.6!).

Along with his weight, Peter had the entire panel of phenemena of the so-called "metabolic syndrome", or pre-diabetes:

--Triglycerides 238 mg/dl and associated with extremes of excess VLDL and IDL
--High blood pressure
--Blood sugar 115 mg/dl
--High c-reactive protein
--Small LDL particles 99% of total LDL

Interestingly, Peter's HDL was a surprisingly favorable 58 mg/dl (HDL is usually low in this syndrome). However, when broken down by size, he had nearly zero large, healthy HDL (sometimes called HDL2b). Though total HDL was favorable, most of it was simply ineffective.

Peter eliminated snacks and processed foods, particularly bread; increased his reliance on healthy oils and lean proteins; incorporated soy protein; increased vegetables. He added 30 minutes of a rapid walk on a treadmill every day. He added vitamin D to achieve a blood level of 50 ng/dml. He added a magnesium supplement.

Peter has lost 31 lbs. in the last year. Weight 207 lbs., BMI 28.1 (desirable <25). Blood sugar: 96 mg/dl; triglycerides: 56 mg/dl; HDL 71 mg/dl with 35% in the large fraction; small LDL 45% of total. Not perfect, but a damn site better.

Control of metabolic syndrome is an achievable goal for over 90% of people, just with these simple efforts. We haven't yet had a chance to assess the effect on the progression or regression of Peter's heart scan score, but he has, at the very least, spared himself a future of diabetes and all its complications.

Heart Scan Curiosities #6
















This is a "slice" from a normal heart scan in a 58 year old woman. Heart scan score zero. Look at the lungs, the dark areas left and right of the heart in the center. The lungs are also normal. Black represents normal density, healthy lung tissue. The white streaking is just normal lung blood vessels. This person doesn't smoke.


















This woman smokes a pack of cigarettes a day and has done so for 45 years ("45 pack-years"). She had a surprisingly low heart scan score (at age 64) of only 71, despite the smoking. However, look at this woman's lungs. It's a little tough to make out, since the computer graphics loses some of the resolution. But you can see the near absence of lung tissue on both sides. This is an advanced phase of the destructive lung disease, emphysema, from smoking. Even if she quit smoking today, the destroyed lung tissue never grows back. She literally has huge gaps or holes in her lungs where lung tissue used to be.

Smoking is among the most destructive, terrible things you can do to your body, short of swallowing strychnine or jumping off a building. Stay as far the heck away from cigarettes as you possibly can. If you are exposed to "secondary" smoke, insist that the person never smoke in your presence. It's not the smell that destroys your lungs or causes coronary plaque (though it is indeed foul), it's the actual smoke.

Should you become a vegetarian?

Do you need to become a vegetarian in order to reduce your heart scan score?

No. Plain and simple. We’ve had many non-vegetarians drop their scores.

That said, are there still advantages to following a vegetarian diet, or some variation on the vegetarian theme?

Yes, there are. Let’s put aside the moral or religious arguments in favor of not eating animals—the need to eliminate killing animals for food, elimination of suffering common in modern livestock practices, Kosher considerations, etc. (Not that there aren’t real arguments here. Our focus for this conversation is not, however, the moral dilemma, but the health argument.)

Some of the most unhealthy people I’ve ever met, mostly males, are proud carnivores who boast of their prodigious capacities to eat meat. Unfortunately, it’s hard to tease out the ill-effects of excessive meat eating, since these same men also tend to be substantially overweight, smoke, drink excessively, and fail to get exercise unless their job is physically demanding. You know the type.

What advantages does a vegetarian obtain? A number of studies have suggested that the reduced saturated fat, reduced exposure to parasites, as well as reduced exposure to the antibiotics and hormones now used routinely in livestock-raising practices, do indeed provide benefits to the vegetarian. Thus, vegetarians tend to be substantially thinner, experience less bowel cancer, have less diabetes and heart disease, and live longer.

(If you are interested in reading or seeing more about just how inhumane modern livestock practices are, take a look at the video, "Meet Your Meat" at meat.org. Be sure not to view this after dinner.)

Of course, some of the disadvantages of eating animal products diminish when free-range livestock are eaten, i.e., livestock not raised in the inhumane cramped, filthy conditions of livestock factories, but in the open, grazing or rooting freely. These animals tend to have different fat compositions and taste different.

The advantages of vegetarianism, however, have blurred in recent years, since many so-called vegetarians have failed to maintain the distinction between naturally-occurring foods and processed foods. So, Ritz Crackers, Oreo cookies, whole wheat bread, and Raisin Bran fit into a vegetarian program, but they’re awful for your health. I’ll occasionally meet a self-proclaimed vegetarian who looks every bit as unhealthy as a conventionally eating American, that is, overweight, pre-diabetic person with a developing heart scan score.

So it is not necessary to be vegetarian to reduce your score. You might consider vegetarianism for other reasons, such as moral considerations, or to reduce your risk for cancer. But it is not necessary to drop your heart scan score. A non-processed food diet? Now that's is worth giving serious consideration.

Let's make it a lot easier

The American Heart Association just released a new set of consensus guidelines on heart disease prevention in women: Evidence-Based Guidelines for Cardiovascular Disease Prevention in Women: 2007 Update

For those of you following the Heart Scan Blog and the Track Your Plaque program, there will be little new in the guidelines. In fact, you'll wonder if the date on the front of the report should be 1987, rather than 2007. Did you know that you should exercise and eat healthy?

Take a look at the list of risk factors for coronary vascular disease (CVD) listed in the report:

Major risk factors for CVD, including:
Cigarette smoking
Poor diet
Physical inactivity
Obesity, especially central adiposity
Family history of premature CVD (CVD at <55>

Progress: You'll notice that buried inside the list is "Evidence of subclinical vascular disease (e.g., coronary calcification)". Just a few short years ago that wouldn't have even been included.

The Track Your Plaque contention is that, for the great majority of women, this list could be shortened to one item: coronary calcification. As time goes on, the people who argue and draft these guidelines will come to the realization that coronary calcification is the disease--it's not a risk for the disease, a predictor of the disease. Coronary calcification is the disease itself. The other items on the list recede way into the background when you know whether or not coronary atherosclerosis is present, i.e., you know your heart scan score (of coronary calcium).

The report goes to say such things as taking a little bit of fish oil is a good idea, maintaining a normal blood pressure is desirable. . . yada yada yada. You've heard this all before.

A major part of the treatment guidelines are devoted to LDL cholesterol reduction with statin agents. You shouldn't be surprised. It's amazing what $22 billion dollars in revenues will buy.

A closing paragraph reads:

'Population-wide strategies are necessary to combat the
pandemic of CVD in women, because individually tailored
interventions alone are likely insufficient to maximally prevent
and control CVD. Public policy as an intervention to
reduce gender-based disparities in CVD preventive care and
improve cardiovascular outcomes among women must become
an integral strategy to reduce the global burden of
CVD.'


Say that again? If you understood that bit of gobbledygook, you're a lot smarter than me.

Don't look to the American Heart Association report for any new ideas. It reminds me of the politician who reminds everybody of what a devoted family man he is: It has nothing to do with his policies. It just makes him look good. If compared to prior report, the 2007 report does indeed represent progress--but just oh so little.

No wonder nobody talks about real prevention

Take a look at this eye-opening statement taken from a well-written NY Times article about Dr. Arthur Agatston, the South Beach Diet and now South Beach Heart Program books:


'We have made major improvements in prevention,” Dr. Gregg W. Stone, the director of cardiovascular research at Columbia University, says. “But it’s difficult. It takes frequent visits, a close relationship between a physician and a patient and a very committed patient.'

Which is exactly the atmosphere Dr. Agatston’s practice tries to create. Nurses there give patients specific cholesterol goals to meet and help them deal with the side effects of the drugs they are taking. A nutritionist, Marie Almon, meets with patients frequently enough to discuss real-life issues like how to stick to a high-fiber Mediterranean diet even on a cruise or a business trip.

There is only one problem with this shining example of a medical practice: it is losing money.



From NY Times, January 24, 2007. What’s a Pound of Prevention Really Worth? (Find the full text at http://www.nytimes.com/2007/01/24/business/24leonhardt.html?ex=1172379600&en=4268a738e82857da&ei=5070.)

It gets at one of the fundamental reasons why your cardiologist will probably never talk to you about an intense approach to prevention: it doesn't pay. Because John Q. Cardiologist focuses, instead, on how to increase procedural volume, train how to put in the next best defibrillator, etc., there is little consciousness about preventive issues. Just the simple matter of taking fish oil causes their eyes to glaze over.

That's why the Track Your Plaque program exists: it is a portal for the kind of information you cannot get. Of course, you could read all the scientific studies, attempt years of trial and error, and try to gain a sense of how to do this yourself. Or you could follow this program. We are proud to not worry about generating procedural profits. We ar unbiased by drug or medical device money. We say exactly what we mean.

By the way, we are on a current push to really "beef-up" our online discussions via real-time chat. Long-term, we'd like to be able to offer chat with our staff many hours every day. Be patient. It will happen, but not today.

HDL and vitamin D

I know of no published reports on this question, but I've now seen numerous people experience significant jumps in HDL with raising blood vitamin D to 25-OH-vitamin D3.

Last week, for example, I had a man who had struggled with raising HDL from a starting level of 28 mg/dl. On niacin, exercise, weight loss, fish oil, red wine, and cilostazol (a prescription agent that I use occasionally that raises HDL), his HDL rose to 41 mg/dl--better, but hardly to our goal.

I added vitamin D, 4000 units, and raised his 25-OH-vitamin D3 level from 22 ng/ml to 53 ng/ml. Next HDL: 73 mg/dl! Small LDL improves along with a rise in HDL.

Not everybody's response is this dramatic. I see more typical rises of 5 to 10 mg/dl every day. I'm uncertain of why the response is inconsistent, though people who begin with lower vitamin D levels seem to experience a larger HDL increase. I wonder if the partial normalization of insulin and glucose responses is at work, or some anti-inflammatory effect.

Vitamin D provides so many other benefits, as well as HDL-raising. I hope you've gone to the effort to have your blood level checked to determine your replacement need. If not, now's the time. February represents your nadir (lowest point) for 25-OH-vitamin D3 blood levels.

Even more Michael Pollan

"Eat food. Not too much. Mostly plants.

That, more or less, is the short answer to the supposedly incredibly complicated and confusing question of what we humans should eat in order to be maximally healthy. I hate to give away the game right here at the beginning of a long essay, and I confess that I’m tempted to complicate matters in the interest of keeping things going for a few thousand more words. I’ll try to resist but will go ahead and add a couple more details to flesh out the advice. Like: A little meat won’t kill you, though it’s better approached as a side dish than as a main. And you’re much better off eating whole fresh foods than processed food products. That’s what I mean by the recommendation to eat “food.” Once, food was all you could eat, but today there are lots of other edible foodlike substances in the supermarket. These novel products of food science often come in packages festooned with health claims, which brings me to a related rule of thumb: if you’re concerned about your health, you should probably avoid food products that make health claims. Why? Because a health claim on a food product is a good indication that it’s not really food, and food is what you want to eat."


Michael Pollan, author of my latest favorite book, The Omnivore's Dilemma, wrote a wonderful piece for the New York Times entitled "Unhappy Meals". You can find the full text at http://www.nytimes.com/2007/01/28/magazine/28nutritionism.t.html?ex=1172120400&en=a78c20f4da0cdc7b&ei=5070. (Another favorite read of mine, The Fanatic Cook's Blog at , alerted me to Pollan's article. Incidentally, take a look at the Fanatic Cook's latest posts--very entertaining and informative. She's got incisive insight into foods as well as a great sense of humor.)

Pollan goes on to say that...

"...typical real food has more trouble competing under the rules of nutritionism, if only because something like a banana or an avocado can’t easily change its nutritional stripes (though rest assured the genetic engineers are hard at work on the problem). So far, at least, you can’t put oat bran in a banana. So depending on the reigning nutritional orthodoxy, the avocado might be either a high-fat food to be avoided (Old Think) or a food high in monounsaturated fat to be embraced (New Think). The fate of each whole food rises and falls with every change in the nutritional weather, while the processed foods are simply reformulated. That’s why when the Atkins mania hit the food industry, bread and pasta were given a quick redesign (dialing back the carbs; boosting the protein), while the poor unreconstructed potatoes and carrots were left out in the cold.

Of course it’s also a lot easier to slap a health claim on a box of sugary cereal than on a potato or carrot, with the perverse result that the most healthful foods in the supermarket sit there quietly in the produce section, silent as stroke victims, while a few aisles over, the Cocoa Puffs and Lucky Charms are screaming about their newfound whole-grain goodness."


Not everything Pollan says is new, but he says it so eloquently and cleverly that he's worth reading. If you haven't yet read Omnivore's Dilemma, or just want a condensed version of the book, the New York Times piece is a great piece of the world according to Michael Pollan.
Is an increase in heart scan score GOOD?

Is an increase in heart scan score GOOD?

In response to an earlier Heart Scan Blog post, I don't care about hard plaque!, reader Dave responded:

Hello Dr Davis,

Interesting post about hard and soft plaque. I recently had a discussion with my GP regarding my serious increase in scan score (Jan 2006 = 235, Nov 2007 = 419).

After the first scan we started aggressively going after my LDL, HDL and Trig...196,59,221

And have them down to 103, 65, 92 - we still have a way to go to 60/60/60 [The Track Your Plaque target values]-

So the increase is a surprise, but my doctor said that the increase could in part be cause some of the soft plaque had been converted to hard plaque and the scan would show that conversion.



Dave's doctor then responded to him with this comment:

"Remember that although your coronary calcium score has gone up, this does not mean that you are at greater risk than you were a year ago. Remember that the most dangerous plaque is the not-yet calcified soft plaque, which will not show up on an EBT [i.e., calcium score]. It is only the safe, calcified plaque that can be measured with the EBT. [Emphasis mine.] For your score to go up like it did, while your lipids came down so much, what had to happen was that lots of dangerous unstable plaque was converted to stable, calcified plaque. There are no accepted guidelines for interpreting changes in calcium scores over time, because the scores tend to go up as treatment converts dangerous plaque to safer plaque. We do know that aggressively lowering LDL reduces both unstable and stable plaque, and we know that risk can be further lowered by adjuvant therapy such as I listed above."


Huh?

This bit of conventional "wisdom" is something I've heard repeated many times. Is it true?

It is absolutely NOT true. In fact, the opposite is true: Dave's substantial increase in heart scan score from 235 to 419 over 22 months, representing a 78% increase, or an annualized rate of increase of 37%. This suggests a large increase in his risk for heart attack, not a decrease. Big difference!

Dr. Paulo Raggi's 2004 study, Progression of coronary artery calcium and risk of first myocardial infarction in patients receiving cholesterol-lowering therapy in 495 participants addresses this question especially well. Two heart scans were performed three years apart, with a statin drug initiated after the first scan, regardless of score.

During the period of study, heart attacks occurred in 41 participants. When these participants were analyzed, it was found that the average annual increase in score over the three year period was 42%. The average annual rate of increase in those free of heart attack was 17%. The group with the 42% annual rate of increase--all on statin drugs--the risk of heart attack was 17.2-fold greater, or 1720%.

The report made several other important observations:

--20% of the heart attack-free participants showed reduction of heart scan scores, i.e., reversal. None of the participants experiencing heart attack had a score reduction.
--Only 2 of the 41 heart attacks occurred in participants with <15% per year annual growth, while the rest (39) showed larger increases.
--The intensity of LDL reduction made no difference in whether heart attacks occurred or not. Those with LDL<100 mg/dl fared no better than those with LDL>100 mg/dl.

Dr. Raggi et al concluded:

"The risk of hard events [heart attack] was significantly higher in the presence of CVS [calcium volume score] progression despite low LDL serum levels, although the interaction of CVS change and LDL level on treatment was highly significant. The latter observation strongly suggests that a combination of serum markers and vascular markers [emphasis mine] may constitute a better way to gauge therapeutic effectiveness than isolated measurement of lipid levels."

This study demonstrates an important principle: Rising heart scan scores signal potential danger, regardless of LDL cholesterol treatment. Yes, LDL reduction does achieve a modest reduction in heart attack, but it does not eliminate them--not even close.

These are among the reasons that, in the Track Your Plaque program, we aim to correct more than LDL cholesterol. We aim to correct ALL causes of coronary plaque, factors that can be responsible for continuing increase in heart scan score despite favorable LDL cholesterol values.

So, Dave, please forgive your doctor his misunderstanding of the increase in your heart scan score. He is not alone in his ignorance of the data and parroting of the mainstream mis-information popular among the statin-is-the-answer-to-everything set.

Just don't let your doctor's ignorance permit the heart attack that is clearly in the stars. Take preventive action now.

Comments (30) -

  • Anonymous

    11/20/2007 5:41:00 PM |

    Dr Davis,

    What should Dave do?  He appears to have improved his LDL:HDL ratio as well as his total C to HDL ratio substantially, but his CAC score jumped significantly.  Maybe look at other risk factors?

    The info here gives no indication of median blood pressure for Dave.  LP(a)?  No indication of particle sizes. But, which of these or others would be most likely to be Dave's downfall in attempting to mitigate a future hard endpoint?

    I don't ask this lightly, I myself am trying to follow the TYP program and keep my high-for-my-age 29 CAC score from growning.  But, I'm frankly not looking forward to my rescan in about a year.  I'm a bit worried about the, "What if my scan shows a dramatic increase?  What then?"

    Thank you for the valuable information you provide.

    :LaughingCT

  • Dr. Davis

    11/20/2007 11:17:00 PM |

    I would urge Dave to follow all the principles of the Track Your Plaque program, including:

    1) Fish oil to provide minimum 1200 mg EPA + DHA per day

    2) Correction of all concealed lipoprotein patterns such as IDL and Lp(a)

    3) Vitamin D raised to 50 ng/ml--crucial!

    4) Normalization of blood pressure, including during exericse.

    5) Normal blood sugar (<100 mg/dl).

    Further efforts might be required, depending on the long-term effects on rate of plaque growth.

  • Ross

    11/21/2007 3:41:00 AM |

    My question is: how repeatable do you think the scores are on the CT scan?  Are they bulletproof (+/- 5% no matter where measured), consistent by analyst (+/- 5% with the same doctor analyzing the scan), or...?  

    I am currently visiting my brother in law, who is an FP doctor with a private practice.  One of his professional friends, a cardiologist who seems a cut above (thinks stenting is a cop-out), recently told him that he only trusted two centers in the mid-Ohio region to score a 16-slice CT scan accurately, and that even then, the variability was still too high for his taste.  Two numbers within 20% were within his expected error bars and weren't different enough to indicate any change to him.  Two different scan centers?  He wouldn't even compare the two scan scores.

    In my own job (software), I've had to manage human-measured numbers over and over again.  One observation keeps coming up: a single value doesn't mean much without an understanding of the accuracy of that value.  I really am curious about how you estimate confidence intervals on CT scan scores.

  • Dr. Davis

    11/21/2007 3:55:00 AM |

    Hi, Ross--

    Excellent questions.

    Several thoughts:

    1) 16-slice scanners are, unfortunately, prone to wider error in heart scan scoring, perhaps as much as 20%. The variation in scoring on an EBT or 64-slice device is far less.

    2) Variation from scan to scan, when expressed as percent, depends to a great degree on the score itself. Lumping all scores together, variation should be no more than 8-9%. However,a low score of, say 2, then repeated at 4 means 100% variation. However, the same absolute difference of 2 but with a score of 1002 and repeated at 1004 is <1% variation. Therefore, higher scores assume much less percent variation, usually <5%.

    3) Variation among different reading physicians tends to be a minor issue, since much of the scoring is done by standard criteria determined by software, not the human eye. The only real source of human variation comes from disputable areas, such as the mitral valve (which can sometimes encroach into the coronary area and appear like plaque) and the mouth of arteries, which can be debated as being in the aorta or in the coronary arteries themselves. However, these disputable areas are issues in <5% of scans.

  • Tom

    11/21/2007 4:30:00 AM |

    It's interesting that a 29 year old is able to track his plaque. I'm in my 60's now and recently found your site AFTER bypass surgery and a calcium score >700 via a 64 slice scan.
    In reading past comments, those of us having had the heart procedure are now unable to follow our progress via the cac score. Until this post I had hoped to use your recommended blood tests for indication of progress, but if LDL reduction achieves a modest risk reduction, we are left without a specific guide.
    Question: Was the progress in blood tests in dave's case a result of statins ?

  • Dr. Davis

    11/21/2007 12:46:00 PM |

    That's why lipoproteins are so important--they provide other indicators. In my experience, people who have LDL cholesterol as the sole cause of heart disease are a very small minority. The vast majority of people have multiple causes beyond LDL.

    Also, about 50% of people can still get a heart scan score after bypass surgery if you find a center willing to do a detailed analysis. You will need to ask.

    Also, I don't know what Dave did, since he is a reader and everything he posted is above. Are you there, Dave?

  • Dr. Davis

    11/21/2007 5:41:00 PM |

    Hi, Paul--

    I think your doctor might be confusing heart scans with CT coronary angiograms. She is right in saying that CT angiograms (using X-ray dye) require a lot of radiation; 100 chest x-rays worth with present technology.

    However, a plain heart scan to generate a heart scan score requires 4 chest x-rays worth on an EBT device, 8-10 on an 64-slice multi-detector device.

    See the Track Your Plaque Special Report, Radiation and Heart Scans: The Real Story at http://trackyourplaque.com/library/fl_06-021radiation.asp.

  • Anonymous

    11/21/2007 6:01:00 PM |

    Regarding repeatability, there is a 2005 study by Serukov, Bland, and Kondos that shows that the repeatability is a function of the square root of the calcium score, and that volume score is more repeatable than Agatston score. The reference is

    “Serial Electron Beam CT Measurements of Coronary Artery Calcium: Has Your Patient's Calcium Score Actually Changed?” Alexander B. Sevrukov, J. Martin Bland and George T. Kondos, American Journal of Roentgenology 2005; 185:1546-1553
    http://www.ajronline.org/cgi/content/full/185/6/1546

    In this report, the standard deviation of the difference between two sequential calcium scored is

    SDAG130 = 2.515 *sqrt(avg score)
    SDVol130 = 1.758 *sqrt(avg score)

    This results in the following values, where SDA is the standard deviation for the Agatston score and SDV is the standard deviation for the volume score.

    Score-SDA--%SDA--SDV--%SDV
    5-----5.62---112%---3.93--79%
    10----7.95---79%----5.55--56%
    20----11.2---56%----7.86--39%
    50----17.7---35%----12.4--25%
    100---25.1---25%----17.5--18%
    200---35.5---17%----24.8--12%
    300---43.5---14%----30.4--10%
    400---50.3---12%----35.1---9%
    500---56.2---11%----39.3---8%
    600---61.6---10%----43.0---7%
    700---66.5----9%----46.5---7%
    1000--79.5----7%----55.5---6%

    These values show why many people use 15% as a breakpoint - only if the score has changed by more than 15% can it be said that the change is real. And this is only true for scores above 200 or so.

    Harry

  • Anonymous

    11/21/2007 7:17:00 PM |

    My cardiologist told me that EBT scanning is not recommended for anyone under the age of 30. Is this true? If so, how do I (29 years) reliably know that I am at risk?

    I discovered your blog recently. Since I have a very bad family history of diabetes, high blood pressure, and cholesterol, I decided to visit a cardiologist last month so that I can request for an EBT scan. He said that I'm too young for that, and has instead asked me to take a Carotid IMT and Stress test - are these tests reliable enough to provide insight on my risk? Could these tests return "false positive" values?

    I had found during a blood test I did this July only to find that my triglycerides were at 600!! The other cholesterol values were bad too - totalC-HDL-LDL-Tri (255-31-Not measurable-600)

    Since then I have found your blog, lost around 25 lbs and did a VAP recently (I asked for NMR and all I got from doctors - what? What the heck is that?) So I settled for a VAP, since they knew about it.

    I did a VAP along with a comprehensive blood test and the measures that came up high were.

    LIPID related:
    Total LDL-C Direct:130 (Normal<130)
    Real LDL-C:110 (N<100)
    Sum Total LDL-C: 130 (<130)
    Remnant LIPO (IDL+VLDL3): 30 (<30)
    HDL-2:9 (>10)
    VLDL3: 14 (<10)

    Non-LIPID related high values:
    Uric Acid: 8.3  (4.0-8.0)
    Fasting Glucose: 104 (65-99)
    Creatine Kinase Total: 631 (<=200)


    LP PLA2 is normal: 164 (115-245)
    HBA1C suggests prediabetic: 5.7 (Normal <6%)


    Due to my very high value of CK Total, I researched online and found that this can increase due to high exercise, and I had it repeated after taking rest, and it returned normal results. My doctor was really surprised about this and initially hesitant to fractionise my CK. I feel empowered that I am able to take charge of my health and preventative care with the
    information that is available online (of course, one needs to tread that carefully and make an informed decision due to various conflicting opinions out there).

    Sorry for the long post, Doc. I have a newfound awareness of my health thanks to your blog, and am very much interested in knowing your inputs. I just hope that more physicians in our country follow your noble path and understand the true value and empowerment of preventive care.

    - Philip

  • Dr. Davis

    11/21/2007 8:09:00 PM |

    Hi, Philip--

    In general, 29 is very young, perhaps too young, unless there is an outstanding family history (e.g., father with heart attack at age 37). Although your lipid/lipoproteins are concerning, it would be highly unusual to have anything but a zero heart scan score at your age.

  • Dr. Davis

    11/21/2007 8:14:00 PM |

    Hi, Harry--
    Thanks for the help!

  • Neelesh

    11/22/2007 4:51:00 AM |

    Hi Dr. Davis,
      I've just bought the Track Your Plaque book, waiting for its arrival. I've had a heart attack a year back.I'm 30 years old with no family history, non-alcoholic, non-smoker and vegetarian.
    The event was attributed to ectatic arteries(Type-III) and a very high level of LP(a)- between 120-130. The standard lipid profile was also marginally higher. If I had not insisted for an LP(a) test after reading Dr Agatston's South Beach Heart Program, I would have never found the LP(a) factor.
       I was stented during the hospitalization and now I'm wondering how effective the heart scan will be, given that the accuracy reduces  with stented arteries (http://circ.ahajournals.org/cgi/content/meeting_abstract/114/18_MeetingAbstracts/II_692-a)

    Thanks!
    -Neelesh

  • Dr. Davis

    11/22/2007 2:35:00 PM |

    Hi, Neeleesh--

    I do advocate heart scanning in people with stents, but I generally suggest that only the unstented arteries be scored. It's imperfect, excluding the most diseased artery, but it's proven a useful compromise, leaving you with two "scorable" arteries.

    The study you cite, however, is not about heart scans, it's about CT coronary angiography, a study that yields "percent blockage" sort of information, not an index of plaque.

    Beyond Lp(a), you should strongly consider vitamin D normalization.  By your first name, I take it you are from India/Pakistan or similar background, an ethnic origin that is associated with severe vitamin D deficiency.

  • Neelesh

    11/22/2007 3:00:00 PM |

    Thanks Dr. Davis. And yes, I'm from India.

  • wccaguy

    11/22/2007 3:13:00 PM |

    Dr. Davis,

    I found your answer to Neeleesh to be interesting in the extreme.  I have a  follow up question to it.

    I don't have specific references for the two facts I have heard but couldn't reconcile:

    1   India has high coronary artery disease incidence.

    2   Your answer to Neeleesh states that vitamin d levels are low in India and Pakistan.  And that would help much to explain the high rate of coronary artery disease in these countries.

    3   And yet India is close to the equator and so vitamin d levels should be relatively high because of sun exposure right?

    The question then is this:  What is the cause of the low vitamin d level in those countries?

    Thanks!

  • Dr. Davis

    11/22/2007 4:00:00 PM |

    It is interesting, isn't it?

    I believe part of the explanation is that, the darker your skin complexion, the more you are "protected" from intense and prolonged sun exposure. But, activation of 7-hydrocholesterol to 25-OH-vitamin D3 may require many hours more exposure. Thus, a fair skinned person might activate D within minutes, while a dark skinned individual might require hours.

    Another factor that has not been thoroughly explored but has potential for yielding enormous insights: Vit D receptor genotypes. That is, vitamin D deficiency may express itself in different ways in different populations. Some might get colon cancer, others multiple sclerosis, others coronary disease.

    I believe that the dark-skinned phenomenon becomes especially an issue when migrating to sun-deprived climates such as the northern U.S.

  • wccaguy

    11/22/2007 6:12:00 PM |

    Hi Doc,

    Your explanation makes sense.

    I did a quick google search and found experts on the problem in India attributing it to the increasing extent to which Indians were staying indoors and not "being active."

    But the vitamin D issue throws the whole question of "activity" into question doesn't it?  It might not be the activity per se but instead the amount of sunlight reduction.

    And if, per your explanation, darker skinned people need more time in the sun than lighter skinned people for Vitamin D3 to be "activated" then than a decrease in sunlight would have more effect on darker skinned people than lighter skinned people.

    Very interesting...  And perhaps INCREDIBLY good news!!!

    Because it means that there might be a cheap effective treatment for the coronary disease epidemic in India.

    Does all that make sense?

  • wccaguy

    11/22/2007 6:19:00 PM |

    Just to follow up one more point on this D3 question...

    I guess what we need to do is find a study which shows a correlation between degree of skin pigmentation and Vitamin D3 activation?

    (I'm not sure if the word "degree" is the right word, but perhaps the question is understood anyway?)

    Answering that question would certainly set up the basis for a scientific study right?

  • Dr. Davis

    11/23/2007 12:56:00 AM |

    Yes, it does. It could serve as the basis for a tremendously interesting study.

  • Dr. Davis

    11/23/2007 1:09:00 AM |

    There are indeed a few studies that document this effect, e.g., Factors that influence the cutaneous synthesis and dietary sources of vitamin D (abstract viewable at Arch Biochem Biophys. 2007 Apr 15;460(2):213-7.)

    However, I am not aware of any study that examines the effect of vitamin D supplementation specifically in this population that tracks coronary atherosclerosis. One British study  in Bangladeshi adults did demonstrate dramatic reduction in inflammatory markers with vit D replacement (Circulating MMP9, vitamin D and variation in the TIMP-1 response with VDR genotype: mechanisms for inflammatory damage in chronic disorders? at http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=12454321&ordinalpos=22&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum  ).

  • Dave K

    11/24/2007 12:21:00 AM |

    Hi Dr Davis,

    Sorry - I have been offline for a couple of days.  Interesting discussion.  I will try and add some detail lipid info.

    July 2007 Blood work showed

    My Lp(a) is 7
    IDL = 10
    VLDL=11
    HDL-2 = 15
    HDL-3 = 50
    VLDL C = 18
    VLDL1+2 = 7

    Currently taking fishoil 1700 mg of DHA+EHA
    Vitamin D 800mg - just incresed to 2000
    Baby Aspirin
    Multivitamin
    Crestor
    Just started Zetia after getting this last scan result
    Eat basic South Beach phase 3
    BMI - 27
    Glucose is 105
    Exercise 4X week...
    Lp-PLA2=120

    Blood pressure high-normal but I don't know about during exercise.  Cardilogist scheduled me for a stress test after this volume increase.

    I have not has a blood test for Vit D.

    Also - I had an angiograham after the first scan because I was having chests pains .... it turned up that I had no blockages whatsoever.  So we judged the chest pains as non cardiac.

    So I am following your list pretty close.  I guess I just have to wait to see how these changes do.  How long would you wait for another scan?

    Not sure what else to add - your website says to consider L-arginie...


    I do have a specific question.  In the scan report it shows where the calcium was found.  Don't know the software, but there was one spot where it showed in the early report that it didn't show in this report (of course there was several new areas) - could that have actually been a reversal at that spot?

  • Dr. Davis

    11/24/2007 1:25:00 AM |

    Small LDL and a deficiency of large HDL, along with modest excess weight, high blood sugar, high blood pressure all suggest you are (or were) likely over-dependent on processed carbohydrates like wheat products. Your pattern would likely respond vigorously to reduction or elimination of these foods and weight loss. Niacin can help this pattern. In our experience, normalization of vitamin D is crucial.

  • Dave K

    11/26/2007 5:51:00 AM |

    Dr Davis,

    Few more data ....

    Some of the treatments have only been for the last 6 months or so.  The Statin was first (of course) and it took almost a year to get something I could tolerate.  The we talked about Vit D (700) and fish oil (800 Omega 3).  After a full Lipid scan around 9 months ago - we decided to add more fish oil.  So the full dosage I listed is only 6 months old or so.

    Also - I love my red wine and I know the number says two glasses and i rarely do two - so its three or four ... which might be my next step....

    From your last response, I assume the VLDL and IDL levels are the ones you would target hardest at this point.

    Don't do a lot of sugar or wheat... Do eat Oatmeal everyday with rasins or blueberries.

    Oh and my other question was with this kind of increase how long would you wait for the next scan?

  • Dr. Davis

    11/26/2007 12:08:00 PM |

    Dave-

    I generally recommend waiting a year after all identifiable causes have been corrected. However, given your minimal doses of vit D, I usually have my patients wait at least six month after vitamin D blood levels are corrected.

  • Dave

    11/26/2007 8:01:00 PM |

    Dr Davis,

    Thank you ... keep up the great work and I'll keep reading... and tracking.

    Dave

  • G

    11/27/2007 12:39:00 AM |

    Neeleesh and DR. D,

    This Canadian physician appears to have a lot of indepth awareness of the diff phenotypes. He suggests (in the author's response) that D2 may not work as well in East Indians (may worsen glycemic control) versus D3 (the more biologically active vitamin D). Very fascinating!!

    http://www.cfp.ca/cgi/reprint/53/9/1435
    Repletion of vitamin D with vitamin D2 is common
    practice, and vitamin D2 can be used safely when monitored
    to achieve normal levels of 25(OH)D. This might
    take 2 to 3 months, as discussed in your letter and in my
    paper, because the half-life is about 2 weeks. Using vitamin
    D3 (1000 to 5000 IU) daily, depending on the level
    of deficiency, will also achieve this goal. I also agree
    that the goal is to achieve levels of 25(OH)D higher than
    100 nmol/L, preferably 100 to 125 nmol/L.
    My concern regarding vitamin D2 is that it is a synthetic
    analogue and might interact with the vitamin D
    receptor differently in various cell systems. It has been
    reported that vitamin D3 might improve glycemic control.
    7 Vitamin D2 has been reported to cause worsening
    of glycemic control in people of East Indian descent.8
    Is this because of vitamin D receptor polymorphism, or
    because of enhanced 24-hydroxylase enzyme activation,
    or is it due to how vitamin D2 interacts with the receptor?
    Until this has been sorted out, I feel safest using
    vitamin D3. There are about 2000 synthetic analogues
    of vitamin D. The search is on for one that can cross the
    blood-brain barrier to treat certain types of brain cancers
    without causing hypercalcemia.9 But then again,
    what other effects would this compound have? There
    are still so many unknowns.
    The first step is to recognize that most Canadians
    do not get enough vitamin D, especially in the winter
    months, because of where we live. This recognition
    might reduce the need for expensive drugs to treat
    various conditions and might improve the well-being of
    many Canadians.
    An ounce of prevention is worth a pound of cure.
    —Gerry Schwalfenberg MD CCFP
    Edmonton, Alta
    by e-mail

    here's the orig article which is one of the most excellent summaries I've seen so far -- great minds think alike -- they advise > 50ng/ml like DR. Davis as well!
    http://www.cfp.ca/cgi/reprint/53/5/841

  • Neelesh

    11/27/2007 4:05:00 AM |

    D,
    Interesting study indeed. Thanks for the information. I guess I have a lot of things to discuss with my cardiologist next week. Smile
    -Neelesh

  • chickadeenorth

    12/2/2007 11:16:00 PM |

    Hi to Gerry Schwalfenberg MD CCFP, do you know any Dr In Edtmn who practices Track your Plague, if so could you suggest names to help me. I live out by Jasper and need a skilled Dr in this treatment program, I would travel to Edtmn.Many thanks.
    chickadeenorth
    (hope its ok for me to ask this here)

  • cadoce66

    4/5/2008 8:37:00 PM |

    hi my aunts 63 yrs and she underwent an angioplasty with a medicated stent .. Shes on PLAVIX and her artery was 90% blocked and she had an evolving AWMI...
    Please advise what she should taketo prevent another blockage or heart attack!
    Thanks!

  • buy jeans

    11/3/2010 10:34:10 PM |

    So, Dave, please forgive your doctor his misunderstanding of the increase in your heart scan score. He is not alone in his ignorance of the data and parroting of the mainstream mis-information popular among the statin-is-the-answer-to-everything set.

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