With new 64-slice CT scanners popping up everywhere nowadays, be sure to get your heart scan with it.
The new scanners do indeed provide wonderful images of the coronary arteries. But, say you have a 20% blockage in one artery by a coronary angiogram generated on one of these devices. What will you do in 1, 2, or 3 years when you want to know if you have progressed? Should you have the CT angiogram repeated?
Well, if you did you'll be exposed to a large dose of radiation--appropriate for a diagnostic test, but not for a screening test. The radiation exposure is not that different from undergoing a full conventional cardiac catheterization, or up to 100 chest x-rays.
"20% blockage" is also, contrary to popular opinion, not a quantitative measure. It is just an estimate of the diameter reduction at one spot. That number says nothing about the lengthwise extent of plaque. It also says nothing about the potential for "remodeling", the phenomenon of artery enlargement that occurs as plaque grows. In other words, if you had another CT coronary angiogram a year later and was told that your blockag was still 20%, in reality you could have had substantial plaque growth but it would not be reflected in that value.
People will come to me after having a CT angiogram for an opinion. Unfortunately, I send them back to their scan center to get a simple coronary calcium score . That measure is easy, quantitative, precise, and can be repeated yearly if necessary to track progression. (Track Your Plaque--I hope most of you get this by now.) Some physicians poke fun at the heart scan, or calcium, score--it's old, boring, only a measure of hard plaque. None of that's true. The coronary calcium score is a measure of total plaque (hard and soft). And when you are empowered to learn how to control and reduce your score, then it's the most exciting number in your entire health program!
Don't fall for the hype. If you go to a scan center and they insist on a 64-slice CT scanner, or if your doctor orders one, you should insist on getting a calcium score out of the test. Just ask. If they refuse, go somewhere else. Centers that refuse to generate a score have one thing on their mind: identifying people with severe blockages sufficient to obtain the downstream financial bonanza--angioplasty, stents, and bypass surgery.