THIS REVIEW is an attempt to answer two questions. First, are there any isotope technics available at the present time that are really useful in the care of patients? And second, what will be the role of isotope technics in clinical cardiology a few years from now? Historical Review The use of isotopes in clinical cardiology was introduced by Blumgart, Yens, and Weiss, who used radium C and a c...

• A number of new technics involving external detection of radioactivity in the blood stream or in tissues have been proposed as means for determining the rate, volume and pathway of blood flow in the intact subject. By virtue of their dependence on indirect, external measurement of indicator (isotope) activity in the body as opposed to direct measurement, these technics have been categorized a...