[1-11C]Acetate as a Quantitative Perfusion Tracer

Our objective was to investigate the properties of [1-11C]acetate as a quantitative perfusion tracer for myocardial PET studies. Methods: We determined the flow dependence of the effective acetate extraction by a comparison with [13N]ammonia in 24 patients at rest (n 5 8) and under pharmacologic vasodilation (n 5 16). Furthermore, we compared the statistical quality of the perfusion values derived with both tracers. Quantification was based on an irreversible 2-compartment model for [13N]ammo-nia and a reversible 1-compartment model for [1-11C]acetate. Area-conserving polar maps were used to determine the corre-lation between the unidirectional uptake parameters of both tracers on a pixel-by-pixel basis for the whole left ventricular myocardium. Results: A fit of a generalized Renkin–Crone for-mula to the data yielded the unidirectional acetate extraction fraction E(f) 5 1 2 0.64e21.20/f. An extraction correction based o