Role of ultrashort-lived radionuclides in cardiovascular studies: /sup 195m/Au ventriculography and simultaneous 201Tl myocardial imaging

The advantages of ultrashort-lived radionuclides (USRN's) are multiple: (1) bedside production, (2) reduction of patient radiation exposure, (3) possibility of administering larger doses of radionuclides, (4) multiple, rapid, sequential, background-free studies, and (5) multiple, simultaneous radionuclide administrations. Simultaneous injection of thallium-201 and gold-195m at maximal exercise and at rest in 24 patients with coronary artery disease (CAD) are described. A bolus of approximately 20 mCi of /sup 195m/Au was followed 1 or 2 sec later by 2 mCi of thallium-201. During the first 25 sec, imaging of first-pass ventriculography was performed in the 260-keV window. Five minutes later /sup 195m/Au had decayed, and conventional planar imaging of 201Tl was performed. Sensitivity for diagnosis of CAD in stress first-pass radionuclide ventriculography was 83%, of wall motion 79%, and 201Tl stress myocardial perfusion was 83%. It was concluded that first-pass ventriculography and simultaneous myocardial perfusion determinations (1) are feasible procedures and (2) appear to offer the possibility of a high-sensitivity and high-specificity test for coronary artery disease