What is a
CORONARY ARTERY CALCIUM SCAN?
A CAC (heart scan) is a specialized, rapid CT
x-ray that provides images that help detect and measure calcified plaque in the arteries.
This simple, quick and non-invasive screening can help identify heart disease before you have signs or symptoms. Knowing your score could help you and your doctor develop a plan to prevent future cardiac events.
Did you know that 80% of adults who have a heart attack before the age of 65 don't survive the first one?
Why is it done?
Every year in America, around 34 million mammograms and 14 million colonoscopies are performed. Why? Yes, because early detection is key to intervention and helping patients survive a potentially fatal disease.
When it comes to heart disease we typically rely on a basic screening that tells us what our risk factors are but we still don't know if we have heart disease. A basic risk assessment - "knowing our numbers" - should be our first step but, too often, this is where we stop. Most women and men learn they have heart disease only after they have suffered a heart attack or, worse, their family finds out when they die. For adults over 40 years of age, with at least one risk factor for heart disease, including a heart scan could help you live a healthier life and potentially save it!
Studies show that 90% of American women have at least 1 risk factor!
When are the scans typically used?
A heart scan is generally used for those who have a moderate risk of heart disease or when the risk is uncertain. According to a study by Johns Hopkins, 15% of participants who were considered at very low risk using traditional risk assessments actually turned out to have high calcium scores. In addition, 35% of those assessed at higher risk were revealed to have no coronary artery calcium, meaning they have a lower risk of heart disease. A heart scan can be a useful tool in determining an effective protocol for treatment or intervention.
Studies have also shown that a heart scan can serve as a motivation for people to make lifestyle changes that can prevent future cardiac events. For others, the screening can detect a potential cardiac event and save the patient's life!
What should you expect?
When you schedule a CAC, make sure you ask about any special instructions like avoiding caffeine or smoking prior to the screening. While you may not be asked to disrobe and wear a hospital gown, you will want to wear comfortable clothing that enables easy access as the technician will place electrodes on your chest. An electrocardiogram (ECG or EKG) will record your heart activity during the scan. While there is exposure to radiation, it is comparable to that of a mammogram.
During the scan, you will lie on a movable table and be placed in the CT scanner, with your head remaining outside of the scanner. The technician will operate the scanner from a separate room however he/she will be able to see and communicate with you during your scan. You will be asked to lie still and hold your breath while the x-ray images are taken. The scanner will make clicking and whirring sounds during the screening which typically takes about 10 minutes.
After the scan, the technician or physician usually discusses your results. You will be given an Agatston score which indicates the total area and density of any calcium deposits. Where there is calcification, there is typically plaque.
ZERO = This score indicates no calcium in the heart and a low risk of a cardiac event within the next 5 to 10 years.
Score 1-10 = Low risk for cardiac event.
Score 11-100 = Mild risk for cardiac event.
Score 101-400 = Moderate risk; this score typically indicates heart disease
Score >400 = High risk of cardiac event within 5 years
You should receive a copy of your scan results and, based on your score, you may be referred to your primary health care provider or a cardiologist for follow-up. For lower scores, a review of your risk factors and recommended lifestyle changes (diet, exercise, smoking cessation) may be done. For scores of 100 or greater, your health care provider may recommend diagnostic tests, prescribe medications and help you develop a more focused prevention plan.
Once you know YOUR score, you can take proactive action that can help you live a healthier life and prevent a heart attack or premature death.
Combined with a risk assessment, this 10-minute scan can more accurately predict your risk for heart disease.
Photo credit: Laurabree Monday, CN2 with
Stephanie Elfert of Carolina Cardiology Associates.
Ivor Cummins interviewing Professor Matthew J. Budoff MD FAAC
Johns Hopkins Medicine:
American Heart Association:
American College of Cardiology:
The Heart Truth for Women