Use of the metabolic tracer carbon-11-acetate for evaluation of regional myocardial perfusion.
The high first-pass myocardial extraction fraction of carbon-11-acetate suggests that its initial uptake depends on blood flow. Accordingly, regional uptake of 11C-acetate at 4 min was compared to regional perfusion determined with nitrogen-13-ammonia in 119 segments in 15 patients with stable coronary artery disease by two methods. A close correlation was observed between initial relative myocardial concentrations (segmental activity normalized to maximal activity) of both tracers (11C-acetate = 0.88; 13N-ammonia + 0.079; s.e.e. = 0.064, r = 0.94, p less than 0.001). Furthermore, segmental net extractions (E.F), as calculated from the input function and segmental activities, of the two tracers correlated closely by E.FC-11 = 0.55E.FN-13 + 0.080 (s.e.e. = 0.045, r = 0.87, p less than 0.001). These relationships indicate that initial regional myocardial uptake of 11C-acetate reflects perfusion and that 11C-acetate permits near simultaneous evaluation of regional oxidative metabolism and of regional myocardial perfusion.
Chan
S Y
SY
Department of Radiological Sciences, UCLA School of Medicine 90024-1721.
Brunken
R C
RC
Phelps
M E
ME
Schelbert
H R
HR
D000085:Acetates; D000368:Aged; D000641:Ammonia; D002250:Carbon Radioisotopes; D003326:Coronary Circulation; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009590:Nitrogen Radioisotopes; D014055:Tomography, Emission-Computed
D000085:Acetates; D002250:Carbon Radioisotopes; D009590:Nitrogen Radioisotopes; D000641:Ammonia