What is a Thallium Stress Test?
A Thallium Treadmill stress test is much like a regular treadmill stress test, the difference is the use of an isotope dye (Thallium) that provides the physician additional information on the coronary blood flow of the patient.
Why is a Thallium Stress Test Required?
Though this test gives the physician the same information as the standard treadmill stress test, it also provides the following information:
- The areas of the heart lacking adequate blood and oxygen
- If the patient has had a heart attack in the past and the area of the heart where the heart attack occurred
What is Involved in Preparation?
- Nothing to eat or drink after midnight before the test
- Do not smoke for at least 4 hours before the test
- Some important questions to ask your physician prior to the test are:
- If you are diabetic, how should you adjust your insulin/food intake the morning/day of the test?
- Should your regular medications be taken the morning/day of the test?
- If you are on Beta Blockers, should this be stopped 72 hours prior to the test for best results?
- Do not apply any lotions, powders, oils to the chest area
- Wear comfortable, loose fitting clothes and walking or athletic shoes
What is Expected Once I Arrive for the Stress Test?
- The test will start in X-ray 2 hours before the actual treadmill part of the stress test where an EMT or an RN will insert an IV in your hand; this is where the isotope will be injected at the peak of exercise. This is a very small dose of radioactive dye that is relatively harmless.
- A set of X-rays is then taken to determine coronary blood flow prior to exercise. You will lie flat on an X-ray table with your arms over your head while a special camera takes pictures of your heart. This can last up to 40 minutes. Once these pictures are completed, you will be taken to the stress test lab.
- Once in the stress test lab, a Respiratory Therapist will place electrodes on your chest to obtain periodic EKG's before, during and after the treadmill stress test.
- The therapist will then put a blood pressure cuff on the upper arm. This is to obtain periodic blood pressures before, during and after the treadmill stress test.
- An EKG and blood pressure are taken with the patient lying down, sitting and standing. The physician and X-ray tech will then be called. There will always be a physician, therapist and X-ray tech present for the entire test.
- You will then exercise on the treadmill, gradually increasing in speed and incline every 3 minutes until you reach a predetermined target heart rate (THR). Depending on your endurance level, this could last upwards of 10 minutes.
- Your heart rate, blood pressure and EKG will be monitored for any adverse changes. It is very important that you keep the physician informed of how you are feeling during the test. If at any time you start experiencing chest pains, shortness of breath, cramping, etc. let him/her know immediately. Otherwise, when you reach your THR the physician will instruct the X-ray tech to inject the isotope into the IV and you will be instructed to walk for one minute more to circulate the isotope.
- You will then be instructed to return to the bed, lie down and recover for a period of 5-6 minutes until your heart rate and blood pressure return to normal.
- The X-ray tech will then ask if you would like anything to eat or drink prior to the follow up X-ray scan.
- A physician must order this test
- This test must be scheduled through Cardiopulmonary Diagnostics
- Bring the order with you and register either at the front desk or at the registration desk between Lab and Cardiopulmonary Diagnostics
When Will I Know the Results of the Stress Test?
Since the physician is in the room for the entire test, he/she will be able to give you an answer right away on the results of your test.