Myocardial Flow Reserve Derived by Dynamic Perfusion Single-Photon Emission Computed Tomography Reflects the Severity of Coronary Atherosclerosis.

A novel single-photon emission computed tomography (SPECT) camera was developed to evaluate dynamic myocardial perfusion flow. However, it is unclear whether myocardial flow reserve (MFR) derived by dynamic perfusion SPECT using the novel SPECT camera (D-SPECT) reflects the severity of coronary atherosclerosis. In the present study, we therefore examined the relationship between MFR using D-SPECT and severity of coronary lesions. The study population comprised 40 patients who underwent both a myocardial dynamic perfusion SPECT study and invasive coronary angiography. The severity of coronary atherosclerosis was evaluated using the Gensini score. All patients underwent a rest/stress SPECT imaging protocol using Tc-99m-sestamibi, and dynamic acquisition was performed. Stress and rest flow was evaluated, and the global and regional MFR was calculated. Global MFR showed a significant negative correlation with Gensini score (r = − 0.345, p = 0.037). Multiple linear regression analysis showed that only global MFR was independently related to Gensini score (p = 0.018). Regional MFR was significantly lower in regions with  90% ≤ stenotic lesions compared with regions with < 90% stenotic lesions (p = 0.009). Global MFR derived by dynamic perfusion SPECT using D-SPECT reflects the severity of coronary atherosclerosis. Further, regional MFR is modulated by severe coronary artery stenotic lesions.