Measurement of absolute myocardial blood flow in humans using dynamic cardiac SPECT and Tc-99m-tetrofosmin: Method and validation

作者：Shrestha Uttam^*; Sciammarella Maria; Alhassen Fares; Yeghiazarians Yerem; Ellin Justin; Verdin Emily; Boyle Andrew; Seo Youngho; Botvinick Elias H; Gullberg Grant T

来源：Journal of Nuclear Cardiology, 2017, 24(1): 268-277.

DOI：10.1007/s12350-015-0320-3

• Dynamic SPECT
• myocardial blood flow quantification
• tracer kinetics
• ammonia PET

Background. The objective of this study was to measure myocardial blood flow (MBF) in humans using Tc-99m-tetrofosmin and dynamic single-photon emission computed tomography (SPECT).
Methods. Dynamic SPECT using Tc-99m-tetrofosmin and dynamic positron emission tomography (PET) was performed on a group of 16 patients. The SPECT data were reconstructed using a 4D-spatiotemporal iterative reconstruction method. The data corresponding to 9 patients were used to determine the flow-extraction curve for Tc-99m-tefrofosmin while data from the remaining 7 patients were used for method validation. The nonlinear tracer correction parameters A and B for Tc-99m-tefrofosmin were estimated for the 9 patients by fitting the flow-extraction curve K-1 = F(1 - A exp(-B/F)) for K-1 values estimated with Tc-99m-tefrofosmin using SPECT and MBF values estimated with N-13-NH3 using PET. These parameters were then used to calculate MBF and coronary flow reserve (CFR) in three coronary territories (LAD, RCA, and LCX) using SPECT for an independent cohort of 7 patients. The results were then compared with that estimated with N-13-NH3 PET. The flow-dependent permeability surface-area product (PS) for Tc-99m-tefrofosmin was also estimated.
Results. The estimated flow-extraction parameters for Tc-99m-tefrofosmin were found to be A = 0.91 +/- 0.11, B = 0.34 +/- 0.20 (R-2 = 0.49). The range of MBF in LAD, RCA, and LCX was 0.44-3.81 mL/min/g. The MBF between PET and SPECT in the group of independent cohort of 7 patients showed statistically significant correlation, r = 0.71 (P < .001). However, the corresponding CFR correlation was moderate r = 0.39 yet statistically significant (P = .037). The PS for Tc-99m-tefrofosmin was (0.019 +/- 0.10)*MBF + (0.32 +/- 0.16).
Conclusions. Dynamic cardiac SPECT using Tc-99m-tetrofosmin and a clinical two-headed SPECT/CT scanner can be a useful tool for estimation of MBF.

• 出版日期2017-2