Advances in cardiovascular imaging have dramatically reduced the impact to the body through minimally invasive diagnostic imaging. In some cases, imaging has replaced more invasive tests such as cardiac catheterization and coronary angiography. Nuclear cardiology is an advanced cardiac imaging technique that uses computed tomography (CT) scanning combined with infusions of radioisotope markers, or radioactive dyes, to create highly detailed 2-D and 3-D views of the heart. The test is conducted if your doctor suspects you have coronary artery disease, or if previous tests did not specify the cause of your symptoms.
The most common procedure is the nuclear stress test (also called a thallium stress test), which provides a view of heart function and blood flow to your heart while at rest and when active. Radioactive dye is injected into your blood stream, and the results show precise imaging of areas of low blood flow through your heart, which can help diagnose and guide your treatment.
Houston Methodist is one of the first facilities in the country to have a dedicated nuclear cardiology laboratory. Our highly skilled clinical experts use the advanced technologies of CT scanning, radioisotope markers and multidimensional views of the heart to allow physicians to assess heart function and the condition of the cardiovascular system.
Nuclear Cardiology Procedure
In preparation for a nuclear cardiology test, your physician may ask you to fast or temporarily stop certain medications. For the tests to be as accurate as possible, it is important to follow your doctor’s instructions prior to the stress test.
During the procedure, the technician attaches sticky patches, or electrodes, to your chest, legs and arms. These electrodes connect to an electrocardiogram (EKG) machine. You will be asked to walk on a treadmill or pedal a stationary bike, during which the incline or resistance will be slowly increased.
When your heart rate reaches a set target, a radioactive dye is injected. The technician uses a gamma camera — a special camera similar to an X-ray machine — to take images of the heart.
After resting for a couple of hours, the technician takes another set of images of your resting heart. The doctor then compares the blood flow through the heart during exercise and at rest.