Doctors can't easily "open the hood" and peer into the heart, making it difficult to determine the cause of chest pain or identify a person at high risk of having a heart attack. As explained in the May 2013 issue of the Harvard Heart Letter, certain tests can spot the presence or absence of heart disease, help gauge the risk of having a heart attack, and guide what treatment, if any, is needed.
The first test is usually noninvasive, meaning nothing is put into the body and it is not opened in any way. This starter, the treadmill stress test, records how well the heart performs when it is forced to work harder. It may be combined with echocardiography, a nuclear perfusion study, or magnetic resonance imaging to "see" if there are blockages in the coronary arteries that nourish the heart and how much of the heart muscle is affected by poor blood flow. The results of these tests are used to determine whether blood flow can be improved with medication and lifestyle changes, or if a procedure such as angioplasty plus stent placement or bypass surgery is needed.
When a stress test is "positive," indicating one or more cholesterol-filled plaques restricting blood flow, a second test is needed to pinpoint their location. This invasive test is usually a special x-ray called an angiogram, performed during cardiac catheterization. It involves inserting a small tube called a catheter into an artery in the groin and maneuvering it into the heart. A dye released from the catheter makes the coronary arteries show up more clearly on an x-ray. Angiograms are excellent for mapping narrowed or blocked sections of an artery.
When it comes to artery-narrowing plaque, bigger isn't necessarily badder. Some small plaques that hardly narrow a coronary artery and cause no symptoms can rupture, causing a heart attack. Many companies are trying to find ways to identify these dangerous lesions before they rupture.
Read the full-length article: "Tests your doctor may order to determine whether you have heart disease"