New agents labelled with technetium 99m for myocardial perfusion imaging.

New agents labelled with technetium 99m (99mTc) are now available for myocardial perfusion imaging. In this article the author reviews the biologic characteristics, the imaging protocols and the clinical usefulness of thallous chloride Tl 201, 99mTc-sestamibi and 99mTc-teboroxime (not yet available in Canada), as well as their complementary roles in the detection of coronary artery disease.