Preliminary evaluation in humans of Tc-99m-Q3, a new tracer for myocardial perfusion imaging.
Trans[99m-Tc-acac2en(TMPP)2]+, where acac2en is N,N'-ethylenebis(acetylacetone iminate) and TMPP is tris-(3 methoxy propyl) phosphine, (shortened Q3) is a new lipophilic Technetium-99m-labelled compound developed for myocardial perfusion imaging. Encouraging data were obtained in the experimental animal. Aim of this study was to perform a preliminary evaluation of Q3 imaging in humans and to compare it with a reference coronary flow tracer such as Tc-99m microspheres. Eight coronary artery disease patients (males, age 58.5 +/- 10 years) were studied. They were injected with 740 MBq of Q3 and single photon emission computed tomography (SPECT) was performed 90 minutes later. After 3 days 740 MBq of Tc-99m microspheres were injected through a pig-tail catheter in the left ventricle (LV), during heart catheterization, and SPECT was acquired 60 minutes later. Q3 images showed a good target/background activity ratio:LV wall/LV cavity = 4.16 +/- 1.2; myocardium/lung = 3.95 +/- 0.52; the related values with microspheres were 6.36 +/- 2.48 (N.S.) and 4.57 +/- 1.07 (N.S.), respectively. Q3 was cleared by the liver and at the moment of SPECT collection the myocardium/liver activity ratio was 1.54 +/- 0.32. The Q3 LV lateral wall/septum activity ratio showed a good correlation with the corresponding microspheres ratio: Q3 ratio = 0.027 + 0.95 microspheres ratio, r = 0.89, SEE = 1.12, p < 0.005.
Department of Clinical Pathophysiology, University of Florence, Italy.
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Bisi
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Sciagrà
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Bacciottini
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Antoniucci
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Santoro
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Buonamici
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Bonino
D003327:Coronary Disease / Q000000981:diagnostic imaging*; D005240:Feasibility Studies; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007553:Isotope Labeling; D008297:Male; D008863:Microspheres; D008875:Middle Aged; D015609:Organotechnetium Compounds; D010720:Phosphines; D010865:Pilot Projects; D015899:Tomography, Emission-Computed, Single-Photon
D015609:Organotechnetium Compounds; D010720:Phosphines; C081212:technetium Tc 99m Q3