Calcium Heart Scan – Priceless
Dr. Friedman recommends for many patients to undergo a relatively new test to evaluate their heart status called a Coronary Artery Calcium (CAC) or Calcium Heart Scan, formerly called “electron beam CAT scan” (EBCT). This is often part of what is called a “body scan,” which also looks for lung cancer and other types of cancer. The CAC scan of the heart detects early calcification in the heart vessels. The CAC scan uses 256 Slice CT imaging of the coronary vessels without any injections, needles or removal of clothing. You lie down, pictures are taken over 30 seconds, and you’re done. The only risk is the radiation exposure, which is minimal (about the same as one xray of your abdomen) and no intravenous injections or needles are required.
Early calcification is a sign of atherosclerosis (coronary heart disease, cholesterol plaques in hear vessels), which is the main cause of death for most Americans. Therefore, screening for atherosclerosis is of primary importance and as an endocrinologist, Dr. Friedman is very concerned with reducing your risks for developing diseases, such as atherosclerosis. Many endocrine conditions, including growth hormone deficiency, Cushing’s disease, and hypothyroidism predispose patients for atherosclerosis.
The CAC scan of the heart is done at most major medical centers and costs about $200. Sometimes it is covered by insurance but often is not. It is a relatively quick procedure that takes about five minutes and one usually gets a preliminary reading at the time it is done. Patients get a calcium score, which indicates how much calcium plaque the patient has in their heart’s vessels. It tells you the number of plaques and how big they are, to come up with a calcium score, and also usually tells which coronary artery contains the plaque. In some circumstances, if the calcium plaques are in a dangerous region, such as in the main coronary artery called the left anterior descending, it may be more dangerous than having them in a more minor heart vessel. A person can get a zero score, which is ideal; and the lower the score, the better. Generally, a score above 300 is considered dangerous. However, recent studies show that the higher the score, the more likely you are to get heart disease, no matter what the score is.
Dr. Friedman recommends the CAC scan in patients that are being considered for treatment of elevated cholesterol and points out that the cholesterol is only a marker for heart disease, and it is much better to look for actual heart disease. Dr. Friedman’s idea is that if you have no calcifications in your heart vessels, it does not really matter what your cholesterol is, as you are not going to die from or develop atherosclerosis. If you do have significant coronary calcification, you should be on drugs designed to lower your cholesterol, such as statin drugs, take an aspirin and undergo other dietary and exercise modification to decrease your chances of having heart disease. Therefore, he feels this test is imperative in many patients.
Questions and Answers:
Question: Why do many doctors not perform this test?
Answer: The test is relatively new and, although there is good data showing that the lower the calcium score, the less likely one is to get heart disease, that relationship is not 100% proven. Therefore, some doctors want to wait until it has been better shown that calcifications do directly correspond to heart disease. In the last few years, the link between calcium score and atherosclerosis has been more proven. Dr. Friedman feels that knowing whether you do or do not have calcifications is quite important.
Question: Who should get this test?
Answer: Dr. Friedman recommends this test in all patients being considered for or currently on cholesterol (statin) treatment. Additionally, a patient who is overweight or has a family history of heart disease should get this test. Most likely, all men over the age of 35 and all women over the age of 40 should get this test. Women considering hormone replacement may also benefit from this test. If you have the following risk factors, you may especially want to get the test:
- High blood pressure
- High cholesterol
- History of tobacco use
- Family history of heart disease (especially in your parents)
- Overweight or obese
- Significant emotional or Job-related stress
Question: Should I take a statin even if I have clean arteries?
Answer: The answer depends on each person, and it has recently been found that statins also lower inflammation. Inflammation also can predispose you to heart disease and other diseases. The best way to monitor inflammation is to do a blood test that Dr. Friedman often gets called a “C-reactive protein” (CRP). If you, therefore, have a high CRP but clean coronary arteries, it still might be worthwhile to be treated with a statin. If you cholesterol is very high, even with clean coronary arteries, it still might be worthwhile to be treated with a statin.
Question: Should I get the CAC scan of the heart, or should I get a stress test or an echocardiogram?
Answer: A stress test will pick up if you have very severe narrowing of your arteries such that you do not get enough blood to your heart on exercise. It is not good for picking up mild atherosclerosis. The CAC scan of the heart will pick up mild atherosclerosis. Similarly, an echocardiogram willonly look at dysfunction of the heart in terms of whether or not you have already had a heart attack, whether you have a certain area of your wall that is not moving, or whether you have heart failure. The CAC scan of the heart will pick up early heart calcifications.
Question: What is the difference between an EKG and a CAC?
Answer: An EKG also only picks up whether you are having current ischemia, which means not enough blood to your heart vessels, had a heart attack, or have a heart arrhythmia. CAC scan of the heart will pick up early calcifications of heart vessels.
Question: What is the difference between a high-resolution CT scan of the heart or an MRI of the heart and an CAC?
Answer: High-resolution CT scan of the heart and electron beam CT scan are similar, but the high resolution CT scan delivers a high dose of radiation, while the CAC scan delivers a minimal dose of radiation. A high-resolution CT scan of the heart probably provides more information about the narrowing of the arteries directly, while the CAC looks directly at the calcifications of the heart. Similarly, an high-resolution MRI of the heart may also deliver more information about the narrowing arteries of the heart.
Question: Should I get a whole-body scan or a CAC?
Answer: The whole-body scan also helps look for cancers, especially lung cancer, and if you are concerned about getting cancer, it may be well worthwhile getting it. However, the whole-body scan can pick up areas that are not cancer but may look like cancer on the whole body scan (false positives), which may lead to unnecessary work-up. In most cases, Dr. Friedman just recommends the CAC.
Question: Are there any persons for whom the CAC should have been done, but was not done?
Answer: President Clinton. When he had an angiogram after having angina, it was frequently discussed why he did not have an CAC scan when he went for his physicals. Since then, CAC scan have become much more popular.
Question: is Dr. Friedman doing any research on CAC scans?
Answer: Yes, along with his colleague Matt Budoff, MD at Harbor-UCLA, Dr. Friedman has an NIH grant to see if a group visit approach to weight loss with diet and exercise in low income patients at MLK Outpatient Center leads to a lowering of calcium scores in the CAC. This is an exciting study that is just starting.
Interested in learning more about Dr. Friedman’s Endocrinology clinic, go to www.goodhormonehealth.com Interested in getting anCAC in Los Angeles, Dr. Friedman recommends Cedars-Sinai 310-423-8000 or Harbor-UCLA (Dr. Budoff) 310-222-2773, firstname.lastname@example.org, www.calciumscan.com.
Conclusion To paraphrase the Mastercard: Price of a CAC: $200. Knowing that you have clean coronary arteries: Priceless.