Coronary artery disease (CAD) is a condition caused by plaque, a sticky substance made of fat, cholesterol and calcium, that builds up in the coronary artery, the main artery that supplies blood to the heart. With The American Heart Association reporting 17.6 million Americans suffer from this potentially fatal disease, early diagnosis is important. Although there is not one single test to conclusively diagnose coronary artery disease, the results of several tests together help doctors diagnose it.
Electrocardiogram
An electrocardiogram, or EKG, is performed by attaching electrodes in specific areas on the body. These electrodes measure the electrical activity in the heart. This test can detect how rapidly the heart beats and whether it beats in a normal rhythm. This test can determine if the heart has sustained damage from a heart attack, which can indicate the presence of CAD.
Stress Test
A stress test measures the activity of the heart during exercise, when the heart is forced to work harder. Under these conditions, the heart requires more blood and more oxygen to function; if CAD is present, the heart will not be able to get what it needs. When a stress test reveals an abnormal change in heart rate, blood pressure or heart rhythm, CAD may be the cause. If symptoms such as shortness of breath or chest pain occur during the stress test, CAD may be the cause.
Some stress tests may also utilize radioactive dye or sound waves (an echocardiogram) to produce images of the heart while under the stress of exercise. These images allow doctors to visualize the flow of blood through the heart, which can allow them to detect CAD.
Coronary Angiography
When the results of other tests and assessment of the symptoms suggest the presence of CAD, doctors may want to perform a coronary angiography. During this procedure, a special dye is injected into the coronary artery through a coronary catheterization. Coronary catheterization uses a long, thin tube inserted through a blood vessel in the arm, groin or neck. Once the tube is threaded into the coronary artery, the dye is released into the bloodstream.
X-rays of the coronary artery and heart are taken to visualize the flow of blood through the coronary artery. This test can help to reveal and blockage present, causing CAD.
Coronary Computed Tomography Angiogram
A coronary computed tomography angiogram, also known a CTA, is an imaging test that can detect the presence of fatty or calcium deposits in the coronary arteries. Although it provides similar information to the coronary angiography, it is a non-invasive test that requires less recovery time.
This test is performed by administering an iodine-containing contrast dye into the bloodstream through an IV. A series of X-rays are then used to send signals to a detector. The doctors at the Cleveland Clinic explain that although this test does run risk from X-ray exposure, its ability to detect plaque deposits is helpful in diagnosing CAD and the extent of the disease.
