Is A Thallium Stress Test The Same As A Nuclear Capillary Stress Test?
Thank you for your query.
A stress test is done for two reasons - 1) to find out if there is a significant reduction in blood supply (ischemia) to the cardiac muscle and 2) in patients who have had a heart attack, to see if there is a possibility of recovery of the cardiac muscle (ie- how much of the damage is permanent and irreversible and how much can be salvaged by restoring blood supply to the heart muscle)
The commonest form of stress testing is the exercise ECG testing -with a treadmill or bicycle. If the patient is unable to do exercise, a pharmacological stress test may be done by using a drug to induce stress to the heart.
Since the ECG stress testing is often not sensitive or specific in detecting ischemia, other forms of stress testing are done. Nuclear stress testing is one such modality where a harmless nuclear isotope is injected and images of the heart muscle are obtained during stess and during rest. The changes in the distribution of the material will indicate whether there is significant ischemia. The nuclear isotopes used are of mainly two types, thallium and compounds of technitium. Either one or sometimes both may be used.
As you can see now, thallium stress test is one type of nuclear stress testing. Thallium is the nuclear isotope used in the study for imaging the heart. Stress may be produced by means of exercise or by means of drugs. Imaging of the heart is done at rest and at peak exercise/immediately after exercise.
I hope this clarifies your doubts. If you have any further questions, feel free to contact me again.
With regards,
Dr RS Varma