Potential role of somatostatin receptor scintigraphy (SRS) for the in vivo imaging of vulnerable atherosclerotic plaques and its association with myocardial perfusion imaging (MPI) finding: A preliminary study

INTRODUCTION: This study was conducted to detect atherosclerotic plaques with somatostatin receptor scintigraphy (SRS) using 99mTc-Octreotide that binds to somatostatin receptor 2.
METHODS: Of 783 patients referred for MPI, 52 cases underwent additional chest SPECT with 99mTc-octreotide and participated in this study. In addition, 43 patients that underwent 99mTc-octreotide scan for NET also received cardiac SPECT. Angiography was performed within 1 month after SRS for 19 patients that showed intensive uptake in SRS and had cardiac risk factors.
RESULTS: Of 52 patients that underwent MPI and SRS, 15 patients showed intensive cardiac uptake in SRS. Moreover, of 43 patients that were referred for NET, 4 patients had marked cardiac uptake in SRS in the heart. Nineteen patients including 12 women and 7 men aged 28 to 84 (58±8.04) years old underwent coronary angiography. The SRS and angiography in the LAD territory were concordant in 15/19 (79%) patients while only 7/15 (46%) cases had concordant MPI and angiography results. In the RCA territory, the SRS and angiography were concordant in 16/19 (84%) cases while MPI and angiography were concordant in 11/15 (73%) cases. In the LCX territory, SRS and angiography were concordant in 15/19 (79%) cases while MPI and angiography were concordant in 6/15 (40%) cases. In the remaining 76 patients who did not undergo coronary angiography based upon cardiovascular profile and SRS, no cardiac events occurred in a follow-up of 2-11 months (7.52±2.71).
DISCUSSION AND CONCLUSION: 99mTc-octreotide uptake was more concordant with coronary plaques relative to MPI findings suggesting a potential role for 99mTc-octreotide in the evaluation of atherosclerosis.