Physicians diagnose coronary artery disease based on medical and family histories, risk factors and the results of a physical exam and diagnostic tests and procedures. No single test can diagnose coronary artery disease so physicians may perform several tests. These include blood tests, X-ray, electrocardiogram, echocardiography, coronary angiography, single photon emission computed tomography (SPECT), or positron emission tomography/computed tomography (PET/CT).

An electrocardiogram (EKG) is a simple test that detects and records the electrical activity of the heart, how fast it is beating and whether it has a regular rhythm. It also shows the strength and timing of electrical signals as they pass through each part of the heart. Certain electrical patterns that the EKG detects can suggest whether coronary artery disease is likely. An EKG also can show signs of a previous or current heart attack.

Echocardiography uses sound waves to create a moving picture of your heart. And provides information about the size and shape of your heart and how well your heart chambers and valves are working.

A chest X-ray takes a picture of the organs and structures inside the chest, including the heart, lungs, and blood vessels.

A coronary angiogram is a procedure that uses X-ray imaging to examine the blood vessels or chambers of the heart. A long, thin, flexible plastic tube (catheter) is inserted into a blood vessel in the upper thigh or arm. The tip of the tube is positioned either in the heart or at the beginning of the arteries supplying the heart, and a dye that is visible by X-ray is injected. The X-ray pictures that are obtained are called angiograms and offer a detailed look inside the blood vessels.

Blood tests check the levels of certain fats, cholesterol, sugar, and proteins in your blood. Abnormal levels may show that you have risk factors for coronary artery disease.

Stress testing is an exercise procedure to make the heart work hard and beat fast while heart tests are performed. If patients can't exercise, they're given medicine to speed up their heart rate. A PET or PET/CT myocardial perfusion imaging test can help the physician detect restricted blood flow. In less severe cases of coronary artery disease, the deficit in blood flow may only be seen after exercise or stress. In more severe heart disease, the blood flow abnormality can be seen at rest as well.

PET/CT myocardial perfusion imaging utilizes a radioactive drug that shows the physician the normal or abnormal patterns of blood flow to the left ventricle of the heart. The muscle tissue around the left ventricle pumps blood to the rest of the body and adequate muscle tone is needed to perform this function well. If blood flow to this heart muscle is restricted by a blockage, then the myocardial perfusion images will show a blood flow deficit.

The PET/CT myocardial perfusion test shows how well blood flows to the heart muscle and is performed while the heart is at rest, but may also be done during exercise or other stress by using a drug that increases blood flow to the heart, mimicking exercise.