Test for Heart Disease
Some heart problems are easier to diagnose when the heart is working hard and beating fast. During stress testing, a patient exercises, or is given medicine, to make the heart work harder and beat faster while heart tests are performed. In an exercise stress test, your heart, breathing, and blood pressure are monitored while you exercise using a treadmill or ride a stationary bicycle. An EKG is usually done before, during, and after the stress test.
In addition to an EKG, other heart disease tests, such as nuclear heart scanning or echocardiography, can be done at the same time. During nuclear heart scanning, radioactive dye is injected into the bloodstream, and a special camera shows the flow of blood to the heart muscle. If a person is unable to exercise, a medicine can be injected into the bloodstream to make the heart work harder and beat faster. Nuclear heart scanning or echocardiography is then done.
Two newer tests that are being done with stress testing are magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning of the heart. An MRI shows detailed images of the structures and beating of the heart. PET scanning shows blood flow to the heart muscle and areas of damaged heart muscle.
An echocardiogram is an exam of the heart using sound waves. An echocardiogram may be done while the person is at rest or exercising (exercise stress echocardiogram).
Nuclear Heart Scan Test
A nuclear heart scan (also known as a thallium stress test) shows areas of the heart that lack blood flow and are damaged. It also can reveal problems with the heart's pumping action. A small amount of radioactive material is injected into a vein, usually in the arm.
A scanning camera positioned over the heart records whether the nuclear material is taken up by the heart muscle (this indicates healthy areas) or not (this indicates damaged areas). The camera also can evaluate how well the heart muscle pumps blood. This heart disease test can be done during both rest and exercise, enhancing the usefulness of its results.