The Simultaneous Assessment of Stress Myocardial Perfusion, Regional Function and Myocardial Viability with Gated Technetium-99m Sestamibi Spect

It is possible to evaluate stress perfusion and rest function at the same time with gated technetium- 99m sestamibi single-photon emission computed tomography (SPECT) acquisition during stress-injected sestaMIBI. The aim of this study was first to compare single injection, single acquisition stress perfusion/rest function Tc-99m sestaMIBI-gated SPECT protocol with echocadiography for the evaluation of left ventricular wall motion and thickening and secondly, to evaluate whether this protocol is an alternative valid method to the conventional separate stress and rest myocardial perfusion SPECT studies for assessment of perfusion defect type and viability. 29 randomized cases were included in the study. Rest Tl-201/stress Tc-99m sestaMIBI dual-isotope myocardial perfusion SPECT protocol was performed as a classical stress/rest SPECT study. SestaMIBI-gated SPECT studies were evaluated for stress perfusion, rest wall motion and thickening. There was good segmental score agreement between gated SPECT and echocardiography for wall motion (74%, kappa=0.44, p<0.001) and th ickening (73%, kappa=0.43, p<0.001). In 15 cases without previous myocardial infarction, excellent agreement (98%, kappa=0.98, p<0.0001) had been found for reversibility between stress sestaMIBI-gated SPECT and dual-isotope myocardial perfusion SPECT. However, in 14 cases with previous infarction, the agreement for reversibility between two methods was not as high compared with the cases without previous myocardial infarctions (%88, kappa=0.80, p<0.01). The results of our study confirm the investigations assuming that sestaMIBI-gated SPECT protocol can replace the classical stress/rest studies. Especially, in cases without previous myocardial infarction, stress sestaMIBI-gated SPECT procedure can be an alternative method for conventional stress/rest myocardial perfusion studies. In such cases, a separate rest perfusion study might not be necessary, resulting in shorter total study time, having gamma camera imaging time and decreasing radiation dose to the patients. If there are nonreversible defects or suspect of attenuation artifacts, rest Tl-201 perfusion study must be added.