Diagnostic Performance of the Simultaneous Acquisition Rest ^{99 m}Tc-Tetrofosmin/Stress ²⁰¹Tl Dual-Isotope Protocol With a Semiconductor Camera　― Comparison With the Rest-Stress ^{99 m}Tc-Tetrofosmin Protocol ―

Abstract

Background: This study compared the diagnostic value of myocardial perfusion imaging (MPI) between the rest-stress ^{99 m}Tc-tetrofosmin protocol (Tc/Tc protocol) and simultaneous acquisition rest ^{99 m}Tc-tetrofosmin/stress ²⁰¹Tl dual-isotope protocol (SDI protocol) with a semiconductor camera.

Methods and Results: We retrospectively studied 147 patients who underwent stress MPI using a cadmium-zinc-telluride camera and invasive coronary angiography within a 3-month interval. The Tc/Tc and SDI protocols were used in 59 and 88 patients, respectively. The sensitivity, specificity, and accuracy of the summed difference score in per-patient analysis were 56%, 85%, and 69%, respectively, for the Tc/Tc protocol and 89%, 82%, and 85%, respectively, for the SDI protocol. The area under the receiver operating characteristic curve was significantly better for the SDI than Tc/Tc protocol for the left anterior descending artery (0.836 vs. 0.674; P=0.0380), the left circumflex artery (0.754 vs. 0.599; P=0.0441), and in per-patient analysis (0.875 vs. 0.707; P=0.0135). There was no significant difference in the diagnostic accuracy of the summed stress score for any vessel or in per-patient analysis between the 2 protocols.

Conclusions: The SDI protocol had a higher diagnostic accuracy for the detection of coronary ischemia than the Tc/Tc protocol.