Coronary Artery Disease
(CAD)
Diagnosis
To determine whether you have coronary artery disease (CAD) and how severe it is, your doctor will discuss your health, lifestyle, and family history with you. This information, plus the results of a physical exam and blood tests, will help determine whether you have certain risk factors for CAD.
Your doctor may also want you to undergo certain diagnostic tests, including one or more of the following:
- Electrocardiogram (ECG or EKG) – An ECG records the electrical activity in your heart. It can detect abnormalities in your heart’s rhythm and specific patterns that suggest portions of your heart may not get enough blood flow. The ECG may also show whether you have a heart attack or find evidence of a previous heart attack. However, ECGs are not perfect tests, as it’s possible to have a heart attack and still have a normal ECG. This is why your doctor may use other tests for diagnosis.
- Stress test – During a stress test, you’ll usually exercise by walking or running on a treadmill or by peddling a stationary bicycle. While your heart is working hard, one of several types of stress tests will be used to evaluate how much blood flow is getting to the heart and how effectively the heart is pumping.
- Occasionally, your doctor may use a stress test that only measures your ECG while you exercise.
- In other instances, your doctor may couple your stress test with an echocardiogram, which uses ultrasound waves to evaluate your heart’s shape and movement while beating.
- A third type of stress test is a nuclear test, in which you would receive an injection of a special radioactive dye, then a nuclear camera would be used to take color-coded pictures of your heart that measure blood flow before, during, and after exercise.
- If you aren’t strong enough to exercise, your doctor may prescribe a particular medication to make the heart beat quickly and forcefully. The medication makes your heart “exercise” when you physically can’t. This type of stress test is called a pharmacologic stress test because medicine is used in place of exercise to make the heart beat fast. During a pharmacologic stress test, the ECG, ultrasound imaging, or nuclear imaging can be coupled with artificial exercise to evaluate your heart, just as with actual exercise.
- Computed tomography (CT) scan – A CT can be used to evaluate the total amount of plaque buildup in your arteries through a test called coronary calcium scoring. Some doctors also use CT to take a picture of the insides of your arteries to look for the specific size and location of potentially dangerous plaques.
- Cardiac catheterization/coronary angiography – If your doctor strongly suspects that you have CAD, you may also go to the cardiac catheterization laboratory for a coronary angiography test. In this test, an interventional cardiologist threads a slender, flexible tube called a catheter into the arteries of your heart and injects X-ray dye. The dye allows the interventional cardiologist to see inside your arteries, find any plaques, measure their severity, and determine what kind of treatment is needed. If you need the artery to be treated with angioplasty and stenting, those procedures are often performed immediately after coronary angiography.