What is a Coronary Calcium Scan?
A coronary calcium study is a specialized CT scan of your heart which enables us to detect the buildup of calcium containing plaque inside the coronary arteries of the heart. The coronary arteries are blood vessels that supply blood to the heart muscle. Plaque buildup inside the coronary arteries are indicative of atherosclerosis. The buildup of plaque, due to atherosclerosis, is composed mostly of calcium, fibrous material, and abnormal fats. This buildup of plaque can cause angina, or chest pain, because it restricts the flow of blood in the artery. However, more ominously, the plaque can rupture, and the blood that flows inside that artery attempts to seal the rupture in the plaque by forming a blood clot. This blood clot can suddenly worsen angina symptoms, or occasionally can seal the artery off completely, resulting in no flow in the artery, leading to what is known as a myocardial infarction, or heart attack. Therefore, a heart attack occurs at the site of plaque rupture that results in a blood clot (thrombosis) of the artery. Therefore, having hardening of the arteries is the same as having calcium buildup in the walls of the arteries.
This plaque buildup is a major risk factor for angina, heart attack and sudden death. The amount of plaque is proportional to the calcium amount. Therefore, the higher the amount of calcium, the greater the amount of plaque in the arteries. Hence, the CT coronary calcium scan quantifies the amount of calcium that you have and gives it a number. The greater the number, the greater the risk to the patient. The CT scan will measure the amount of calcified plaque, and calculate your risk of developing a coronary event such as a heart attack, need for stent placement, and even cardiovascular death. Hence, this test will allow patients to be risk stratified at very low risk, low risk, moderate risk, and high risk. Once identified, appropriate prevention measures can be implemented to prevent progression of plaque buildup and calcium buildup, and avoid rupture of the plaque.
The CT calcium score is a better predictor of coronary events than cholesterol screening and other risk factor screening such as diabetes, high blood pressure, obesity, and smoking. This is because the calcium measured is directly related to the amount of plaque buildup. This test provides the answer to the simple question of: “Do you have coronary artery disease or not?” The methodologies used in the past included a risk assessment which is only a statistical guess based on your age, blood pressure, weight, cholesterol levels, and blood sugar levels. It is not as accurate as the coronary artery calcium score.
Who should get a CT Coronary Calcium scan?
It is predominantly indicated in patients in the “intermediate risk” patients. However that definition is still very vague. Risk factors for atherosclerosis such as pre-hypertension, hyperinsulinemia, hypertension, dyslipidemia, sleep apnea, history of smoking, increased body mass index, very sedentary lifestyle, inflammatory skin conditions, inflammatory bowel disease, peripheral vascular disease, history of stroke, and a history of previous myocardial infarction are typical examples of patients expected to have atherosclerosis, and thus an elevated coronary calcium score.
How is a calcium score interpreted?
The coronary artery calcium score can be converted to a percentile rank based on your age and gender. The lower the calcium score and percentile rank, the less likely you are to have a cardiac event compared to others of your age. If you have any plaque present, which is a score greater than 0, then you need to implement lifestyle changes, and further workup is indicated to determine why you are developing plaque formation. This will include a workup for hyperinsulinemia, or pre-diabetes, high blood pressure, weight management and weight loss, smoking cessation, eating an anti-inflammatory diet, healthy sleep habits, and stress reduction.
0 score: This means you have no plaque. Your risk of a heart attack is extremely low. May even allow discontinuation of some medicines.
1-10: You have a small amount of plaque. Your risk of heart attack is very low.
11-100: You have some plaque, and you have mild heart disease. Your risk of a future heart attack is moderate. You need to implement lifestyle changes now.
101-400: You have a moderate amount of plaque. Your risk of a future heart attack is moderate-high. You will certainly require a workup for underlying causes and need to modify your risk factors through lifestyle changes.
Greater than 400: You have a large amount of plaque. Your risk of a future heart attack is high. You will certainly require a further evaluation of the extent of heart disease, underlying causes, and need to modify your risk factors urgently.
What does an elevated calcium score mean?
It means that this patient already has atherosclerosis, and greater the calcium score, the larger the amount of plaque. A calcium score over 400 is extremely high and places the patient at high risk of developing angina, myocardial infarction, congestive heart failure, and arrhythmias in the future.
Can the calcium score come down?
There are a few studies demonstrating drastic reductions in calcium score. Most studies demonstrate a mild drop with stabilization of plaque with no further increase in the calcium score on repeated studies performed at 24 months. Aggressive lifestyle changes, dietary changes, improved nutrition can all stabilize the progression. Calcium scores in general increase over time, hence we know that those who have had a heart attack before are most likely to have another one. By finding a high score, we can look for risk factors that have not yet been found or treated. For example, one of the main factors that results in progression of disease is hyperinsulinemia, and the insulin levels can only be measured in a blood test and is done very infrequently. Dr. Jamnadas is a strong proponent of measuring insulin levels, and if elevated, will implement powerful dietary interventions to reverse hyperinsulinemia and thereby reduce cardiovascular risk. If serial levels of calcium scores over the years are stable, the patient is at low risk of future events even if the calcium score is high.
How is the coronary calcium scan done?
This procedure is performed in our office, and is a non-invasive CT scan of your heart. It is performed by a CT technologist on a CT scanner with a specialized program. You do not have to fast for this test. However, you should avoid caffeine and smoking for at least 4-6 hours prior to the test. Your heart rate needs to be slower, and occasionally you will require an intravenous injection or a tablet of a beta-blocker to slow the heart rate to obtain a more accurate scan. You will be asked to remove the clothing above the waist and wear a medical gown and remove any jewelry around your chest. EKG electrodes will be applied to your chest to monitor your heart rate, and you will lie on the x-ray table for approximately 5 minutes. The tablet will move very slowly as the images are obtained. The scan is tolerated by even claustrophobic patients because your ahead will always be outside the scanner. You may be asked to hold your breath for 20-30 seconds, and hold very still at times. The entire scan takes approximately 20-30 seconds. From start to finish, the whole test usually takes approximately 15-20 minutes.
How do I prepare for the test?
- You may eat, drink, and take your medications as you usually would. No caffeine/stimulants 6 hours prior to your exam. We would like to have your heart rate as low as possible so that we can obtain good pictures.
- Try to wear comfortable clothing and remove all metal and jewelry from the part that is being scanned. This will include belts, snaps, underwire bras and shirts with decorative beading.
- If you are pregnant or think you might be pregnant, please inform the technologist before your study, as radiation may be harmful to the unborn fetus.
What happens during the test?
- You will lay on a table on your back with your arms above your head.
- Small pads or patches called electrodes will be put on your chest. Wires connect the pads to an ECG (electrocardiogram) machine. The machine records the electrical activity of your heart.
- The table will then move you through the center of a large donut-shaped scanner.
- As you move through the scanner, you will need to stay very still, and you will be asked to hold your breath for a few seconds.
- Most tests only take about 10 minutes.
- A registered CT Technologist will be taking your images and is trained to keep the radiation dose as low as possible.
What happens after the test?
- There are no side effects to this test, and you may resume your normal activities.
When do I get the results of the coronary calcium study?
The images are processed and are usually available the next day. The calcium score for each artery will be determined. The total score represents the calcium buildup in all the coronary arteries combined. The greater the score, the greater the risk of cardiovascular complications in the future. It is probably the most predictive test for cardiovascular disease currently available. A score between 0 and 100 is already abnormal, and puts you at an increased risk but still requires you to modify your risk factors. A score in excess of 400 places you at very high risk, and depending on your symptoms and other factors, you may require further investigation into the physiological effects of the plaque buildup using a nuclear stress test. We always encourage the results of the scan to be discussed in detail with the doctors and mid-level providers, and further recommendations will follow.
The coronary calcium scan has been underutilized for more than a quarter century, mostly because of a lack of understanding of the usefulness of this test. It is the most direct way to establish a diagnosis of coronary artery disease, and risk stratify the patient for future risks of heart attacks, death, and other forms of heart disease. Unfortunately, insurance companies, and some medical organizations have not supported its use for dubious reasons. Knowledge of the coronary calcium score can be a very strong motivating factor for lifestyle modifications, dietary changes, stress management, and pharmaceutical interventions. Most cardiovascular events come unannounced, and do not give the patient an opportunity to have avoided the event with simple preventive measures. Our modern lifestyle habits can be clearly detrimental, and are known to lead to coronary atherosclerosis. Yet, we are led to believe that we are leading a clean, healthy lifestyle and diet. Hence, the first cardiac event comes as a shock. Knowledge of the coronary calcium scan result can result in changes through education to avoid the trap of social indoctrination about what really constitutes a healthy lifestyle and diet. When most patients are asked about their lifestyle and diet, most feel that it is quite good based on their past knowledge and what they have learned from the social structure. This is often slanted by the food industry, advertising, misinformed advisors, and upbringing. There is an ever growing threat of cardiovascular disease, and the coronary calcium scan is an early signal of alarm and a call for action. Coronary artery disease and atherosclerosis is a predominantly preventable disease. It starts as silent coronary calcium buildup, and then years later, if no corrective action plan is implemented, results in severe morbidity and mortality. It is the #1 cause of death in the United States and much of the Western world.
How do I schedule a CT calcium score?
You may call our office at 407-894-4880 or click the button below and one of our staff members will contact you.