Heart Attack

Diagnosis & Tests

Tests used to diagnose coronary artery disease are typically conducted by a specially trained technician or a heart specialist (cardiologist). However, a routine history and physical by your primary care physician (PCP) can often identify early risk factors, and an in-office electrocardiogram (ECG) is often a first step in evaluating coronary artery disease.

Below are some common cardiac tests.

Electrocardiogram (ECG or EKG) and ECG Stress Test

This simple, painless test measures the electrical activity of your heart using electrodes placed on the chest and other parts of your body. You might have the test lying down, or while you’re exercising on a treadmill or bicycle to monitor how your heart responds to increasing levels of physical activity.

Chest X-ray

A chest x-ray can show whether parts of your heart are enlarged, or if there is fluid buildup in your lungs. These can be signs of heart failure, a heart valve problem, or thickening of the heart muscle.


This test uses sound waves to create an image of your heart as it beats. It is not painful and does not require sedation.

Holter Monitor

To test your heart activity over a period of time, your cardiac specialist might give you a portable monitor to use at home. While you wear the monitor on your shoulder (like a shoulder bag), you can perform all your normal activities, except for showering. You usually wear the monitor for a day or two and then return it to your healthcare provider’s office for analysis.  

Nuclear Stress Test

If you have symptoms like chest pain or shortness of breath, your healthcare provider may order a nuclear stress test. You will receive an injection of radioactive dye and images will be taken of your heart while you are at rest.  Afterward, you may be asked to exercise on a treadmill or stationary bicycle. (If you are unable to exercise because of severe arthritis or other health conditions, you may receive an injection to speed up your heart.) Another dose of radioactive dye may be given during the test through a small intravenous (IV) tube, and your blood pressure and heartbeat will be monitored during the test (using an ECG). Another set of images will be taken at that time.  After resting for a prescribed time you might have another set of images taken. The nuclear stress test images show the specialist if there are any damaged areas in your heart. The images may also show whether the arteries that bring blood to your heart muscle are blocked or narrowed, or if your heart is enlarged. It also measures how well your heart is pumping blood (this is called the ejection fraction).

Cardiac Catheterization (Angiogram)

The heart specialist threads a tiny tube (catheter) through an artery in your arm or leg into the arteries of your heart. A dye is injected into the tube and the dye travels through your heart chambers and arteries. The dye can then be seen on a specialized x-ray machine. This shows the pumping action and circulation of blood through your heart, and any blockages you might have in your coronary arteries. 

Cardiac MRI

A large machine containing a strong magnet and radio waves creates a picture of the inside of your heart. This test can provide more detailed information about how your heart valves and other parts of your heart are working. 

Coronary Calcium CT Scan

In coronary artery disease, calcium builds up in plaques in the walls of arteries. This narrows the blood vessels and raises your risk of a heart attack. Healthcare professionals can estimate your heart attack risk by checking your coronary calcium “score”—even when you have no symptoms.

During the scan, you will lie on a table for a few minutes. You may have electrodes (wires) attached to your chest and be injected with a dye. Coronary calcium scans use electron beam computerized tomography (EBCT or “ultra-fast CT”), an advanced type of x-ray technique that exposes you to the same amount of radiation as 33 chest x-rays. Therefore, repeated scans may raise your cancer risk. This procedure is not recommended if you are either at low or high risk for a heart attack (if you are at high risk, you should already be taking medications and making lifestyle changes). It is recommended for persons at “moderate” risk who have a 10–20 percent chance of having a heart attack within the next 10 years. 


Last Updated July 2020