What to Expect: Nuclear Stress Testing
A nuclear stress test is a very useful advanced diagnostic tool for deciding how well treatment is progressing, stratifying risk for heart disease, finding the cause of new or worsening chest pain, and/or evaluating recovery after a heart attack. Unlike regular stress testing, a nuclear stress test involves the injection of contrast dye into the veins and subsequent monitoring of blood flow using a specialized detection machine.
When patients hear they need a nuclear stress test, they may have some reservations about the use of radioactive material and whether the test will be uncomfortable or even dangerous. In actual fact, the use of nuclear stress testing, when appropriate, is very safe and can help your cardiologist come to a more accurate diagnosis.
With that being said, we would like to give you an idea of what to expect when undergoing a nuclear stress test.
Preparing for Your Nuclear Stress Test
When preparing for the nuclear stress test, you will receive pre-procedure instructions including not eating or drinking anything that contains caffeine for at least 24 hours before the procedure. You may also have to stop taking some of your medications, but do not do so without the explicit instruction of your cardiologist.
During the Procedure
Most of the stress tests performed by heart house physicians are done in the office. Higher risk patient may have their nuclear stress test performed in the hospital setting in case of potential complications. We ask that you arrive for your stress test approximately an hour before your appointment time. Testing begins by injecting a mildly radioactive contrast dye into your veins. You will then be asked to rest for between 15 and 45 minutes to allow the dye to travel through the blood vessels. Special imaging devices track the contrast dye into and out of the heart and through the veins to give your cardiologist a better picture of blood flow.
You will then be asked to walk on a treadmill or use an exercise machine to increase your heart rate. If you have trouble exercising, you will be given medications that mimic the effects of exercise so your cardiologist can see how your heart performs under stress. Various data points will be gathered throughout testing. Once you reach a certain heart rate, additional contrast dye will be injected, and your heart function will be monitored as you recover from the stress test.
During the procedure, most pain patients only feel the discomfort associated with mild to moderate exercise. This may be significant for those who have difficulty exercising due to their cardiovascular condition. Mild chest pain, fatigue, cramps and shortness of breath may all occur and should be discussed with your physician or technician during the test.
While the nuclear stress test is minimally invasive, there are some potential risks of the procedure. These risks are often due to the patient’s health circumstances and not the testing itself. In some cases, patients may experience abnormal heart rhythms, chest pain, shortness of breath, blood pressure issues and potentially skin rashes from the contrast dye. These are often mild and resolve shortly after the procedure. If you have any concerns, please speak to your provider during consultation.
Results and Next Steps
A normal result from a nuclear stress test is usually sufficient to ensure there is no significant cardiovascular problem that needs immediate attention. Abnormal results will require further diagnosis and/or treatment. Some patients may receive stents while others may require cardiac catheter ablation to correct narrowed blood vessels or irregular heartbeats, respectively. Significant arterial blockage may require a bypass procedure. Milder concerns may only require watchful waiting or medication.
Ultimately, the nuclear stress test is a very important and useful diagnostic process that allows us to get a better picture of blood flow through the body. It is critical in diagnosing many significant cardiovascular disorders. While there is some concern about radioactive dye being introduced into the body, this decision to employ a nuclear stress test means that the risks of the contrast dye are far lower than the risk of misdiagnosis.