Coronary Calcium Score,or Heart Scan, it’s becoming a popular test offered by most of the hospitals

as a screening for Heart Disease. It is a test that I support and even advertised  on my facebook group, -https://www.facebook.com/groups/staicuhealthwomen

I am happy with the great response in our community, and as a result , I see many patients with abnormal CT scan as a consult.

The more consults for CT scan I see, the more I realize how confusing it is for patients to interpret the results. I see the tendency to interpret the score as black and white- ” high score , I have coronary disease, and I need now an angiogram” or ” low score, I am so healthy, no preventive medicine is necessary”.

If would be that easy, would it cost less than 100$? 

 

What is Coronary Calcium Score, or Heart Scan and what does it mean?

In the 1980’s   Dr. Arthur Agatston defined a method to assess the amount of coronary artery calcium by using electron beam computed tomography. Calcium is identified by computer programs and quantified as Hounsfield units, which determine the calcium score,- how much calcium is deposited in your coronary arteries. 

The Heart scan is a non-invasive CT scan of the heart, completed in about 10 minutes, that calculates the burden of calcium deposits in your coronary arteries, defined as your Calcium score.

More coronary calcium means more coronary atherosclerosis, suggesting a greater likelihood of significant narrowing  in the coronary system and a higher risk of future cardiovascular events. It does not predict how many narrowings are present or the degree of narrowing, but only identifies the risk of future cardiac events.

 

Certain forms of coronary disease , such as a heart attack, are due to  “soft plaque” atherosclerosis , without any calcium buildup; the soft plaque cannot be detected by  CT scan, which will reveal a score of 0, failing to predict a life-threatening event, such as a heart attack.

 

 

Calcified plaque with Score> 100 and ” soft plaque” score 0

The soft plaque is associated with heart attacks 

The Calcified plaque is associated with angina

 

 

 

 

 

The best way to interpret the Calcium CT score is as a great predictor of Coronary events, and not as a definite presence of heart disease. This is how your Calcium score will look like. The next step is to consult a cardiologist and assess your risk factors  ( HTN, DM, smoking..) and the presence of symptoms. A further treatment decision should be taken only after associating symptoms and risk factors with calcium score.

Let’s break it down with a few examples

• A patient with Calcium score of 3,  with diabetes, obesity, HTN, who gets shortness of breath with climbing one flight of stairs- has significant coronary disease, despite low calcium score; possibly “soft plaque”

• A patient with a score of 250, without any Risk factors, who plays golf and is able to walk 3-4 blocks- may have some degree of coronary disease, but probably not severe narrowing. A stress test, cholesterol control, aspirin would be appropriate.

• A patient with history of Heart attack, open heart surgery, diabetes, – should never get a CT score; we already know there is extensive coronary disease, and no further information from calcium CT is needed it

• A young, 32 years old, active, playing sports, no smoking, no active disease, or Risk factors, may have a falsely high score, triggering a few unnecessary tests.

Coronary calcium score is not meant to assess chest pain and see if symptoms are related to the heart .  A person’s calcium score could be quite low, with significant  coronary stenosis (and vise versa). This test is  a risk assessment only, and a guidance for further testing, or lifestyle modifications, cholesterol therapy, risk factor treatment.

Risk Factors for Coronary Disease

• high blood cholesterol levels

• family history of heart attacks

• diabetes

• high blood pressure

• cigarette smoking

• overweight or obese

• physical inactivity

• carotid, aortic or leg arteries stenosis 

• obstructive sleep apnea

How should you prepare for calcium CT 

No special preparation is necessary . Continue to take your usual medications, but should avoid caffeine and smoking for four hours prior to the exam.

You should wear comfortable, loose-fitting clothing to your exam. You may be given a gown to wear during the procedure.

Metal objects, including jewelry, eyeglasses, dentures and hairpins, may affect the CT images and should be  removed prior to your exam. You may also be asked to remove hearing aids and removable dental work. Women will be asked to remove bras containing metal underwire. You may be asked to remove any piercings, if possible.

Women should always inform their physician and the CT technologist if there is any possibility that they may be pregnant.

 

How is the procedure performed?

The technologist will position you on the CT examination table, usually lying flat on your back. Straps and pillows may be used to help you maintain the correct position and to help you remain still during the exam.

Electrodes (small, sticky discs) will be attached to your chest to perform an electrocardiogram.This makes it possible to record CT scans when the heart is not actively contracting.

Next, the table will move quickly through the scanner to determine the correct starting position for the scans. Then, the table will move slowly through the machine as the actual CT scanning is performed. 

Patients are asked to hold their breath for a period of 10 to 20 seconds while images are recorded.

The entire procedure including the actual CT scanning is usually completed within 10 minutes.

 

Who interprets the results and how do I get them?

A radiologist will analyze the images and send an official report to you. The report may look like this

Calcium Score	Presence of CAD
0	No evidence of CAD
1-10	Minimal evidence of CAD
11-100	Mild evidence of CAD
101-400	Moderate evidence of CAD
Over 400	Extensive evidence of CAD

Follow-up consultation  may be necessary. Sometimes a follow-up exam is done because a potential abnormality is seen on the lungs, such as a nodule. 

Summary

• A fast, short test, with low exposure to radiation

• More than 400 score is correlated to high risk of significant coronary stenosis.

• Calcium CT is a risk assessment tool, not a diagnostic tool for chest pain. To not be confused with Coronary calcium CT angiography, – also a CT scan, which is ordered by cardiologists, more extensive , more informative and covered by insurances. ( needs pre-approval)

• Correlate the score with your other Risk factors and symptoms. It is an addition risk stratification, not a final diagnostic test .

• A score of 0 can still be associated to severe coronary disease, since the ” soft plaque” present in heart attacks does not contain calcium, and is not detected by CT. Also, a score > 400 may still be associated with a mild degree of very calcified stenosis. 

• Not a useful test in patients with documented heart attacks, open heart surgery, or multiple Risk factors with symptoms. The disease is already there, with or without calcium burden.

• Non cardiac findings, such as lung nodules, may be detected. Always follow up with a physician.

• Even though the radiation exposure is low, the test is not necessary in very young patients with low likelihood of coronary disease. False positive high scores may be followed by multiple other unnecessary tests.