Kinetic analysis of 18F-fluorodihydrorotenone as a deposited myocardial flow tracer: comparison to 201Tl.
The goals of this investigation were to assess the accuracy of (18)F-fluorodihydrorotenone ((18)F-FDHR) as a new deposited myocardial flow tracer and to compare the results to those for (201)Tl.


METHODS
The kinetics of these flow tracers in 22 isolated, erythrocyte- and albumin-perfused rabbit hearts were evaluated over a flow range encountered in patients. The 2 flow tracers plus a vascular reference tracer ((131)I-albumin) were introduced as a bolus through a port just above the aortic cannula. Myocardial extraction, retention, washout, and uptake parameters were computed from the venous outflow curves with the multiple-indicator dilution technique and spectral analysis.


RESULTS
The mean +/- SD initial extraction fractions for (18)F-FDHR (0.85 +/- 0.07) and (201)Tl (0.87 +/- 0.05) were not significantly different, although the initial extraction fraction for (18)F-FDHR declined with flow (P < 0.0001), whereas the initial extraction fraction for (201)Tl did not. The washout of (201)Tl was faster (P < 0.001) and more affected by flow (P < 0.05) than was the washout of (18)F-FDHR. Except for the initial extraction fraction, (18)F-FDHR retention was higher (P < 0.001) and less affected by flow (P < 0.05) than was (201)Tl retention. Reflecting its superior retention, the net uptake of (18)F-FDHR was better correlated with flow than was that of (201)Tl at both 1 and 15 min after tracer introduction (P < 0.0001 for both comparisons).


CONCLUSIONS
The superior correlation of (18)F-FDHR uptake with flow indicates that it is a better flow tracer than (201)Tl in the isolated rabbit heart. Compared with the other currently available positron-emitting flow tracers ((82)Rb, (13)N-ammonia, and (15)O-water), (18)F-FDHR has the potential of providing excellent image resolution without the need for an on-site cyclotron.
Marshall
Robert C
RC
Department of Nuclear Medicine and Functional Imaging, E.O. Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA.
Powers-Risius
Patricia
P
Reutter
Bryan W
BW
O'Neil
James P
JP
La Belle
Michael
M
Huesman
Ronald H
RH
VanBrocklin
Henry F
HF
D000818:Animals; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000378:metabolism*; D007090:Image Interpretation, Computer-Assisted; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D008657:Metabolic Clearance Rate; D049268:Positron-Emission Tomography; D011817:Rabbits; D011865:Radioisotope Dilution Technique; D012402:Rotenone / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D013793:Thallium / Q000493:pharmacokinetics*
C494900:fluorodihydrorotenone; D012402:Rotenone; C027549:thallium chloride; D013793:Thallium