Comparison of different radionuclide agents currently in routine clinical use for myocardial perfusion imaging
| Radionuclide | Half life | Activity administered | Effective dose | Mechanism of myocardial uptake | Redistribution | Comments |
|---|---|---|---|---|---|---|
| Mbq, megabecquerel; mSv, millisievert; PET, positron emission tomography. | ||||||
| 201Tl | 72 hours | 60–80 MBq | 15–20 mSv | ATPase-K+ myocyte cell membrane integrity required | Redistributes | Poor quality images; difficult to gate. Prognostic data available; redistribution advantageous for viability detection |
| 99mTc-sestamibi | 6 hours | 800 MBq | 8 mSv | Myocyte mitochondria | Minimal | Versatile agent; increasing use; viability detection validated against 201Tl, dobutamine stress echocardiography, and PET |
| 99mTc-tetrofosmin | 6 hours | 800 MBq | 8 mSv | Not known | Nil | Poorer extraction with vasodilator stress; underestimates ischaemic burden; improved extracardiac clearance suggested |