Different types of radiotracers available for stress testing

Sharing is caring!

What are the different types of radiotracers available for stress testing?

There are three basic categories: thallium-201 ( 201 Tl) and technetium-99m ( 99m Tc)-labeled compounds for SPECT, and positron emitting compounds for PET. 

The below table compares 201 Tl and 99m Tc-labeled compounds. The most commonly used 99m Tc-labeled compounds are tetrofosmin and sestamibi, which have similar imaging and chemical characteristics. 99m Tc-labeled compounds generally provide more flexibility in terms of imaging times.

Because of the photon energy and the number of photons emitted, 99m Tc-labeled compounds are generally easier to use for image acquisition and analysis. PET radiotracers, such as rubidium-82 ( 82 Rb), nitrogen-13 ( 13 N) ammonia, and fluorine-18 ( 18 F) fluorodeoxyglucose (FDG), can be used to evaluate myocardial perfusion and glucose metabolism, respectively. 13 N ammonia has a short (20 minute) half-life, so there are some logistical limitations in using this for PET cardiac imaging.

Comparison of 99m Tc-Labeled Compounds and 201 Tl for Cardiac SPECT SMPI

99m TC-LABELED COMPOUNDS201 TL
Energy140 keV (ideal for gamma camera)69-83 keV (suboptimal for gamma camera)
First-pass studies of ventricular functionFeasibleNot feasible
Gated imagingReadily accomplishedCount rate marginal for gated imaging
Stress/rest imagingTwo injections required since there is no radiotracer redistribution over timeCan be accomplished with one injection since there is radiotracer redistribution over time

Sharing is caring!

15585

Sign up to receive the trending updates and tons of Health Tips

Join SeekhealthZ and never miss the latest health information

15856
Scroll to Top