REGIONAL GLUCOSE-UPTAKE WITHIN HYPOPERFUSED SWINE MYOCARDIUM AS MEASURED BY POSITRON EMISSION TOMOGRAPHY

Chronic myocardial ischemia and 2-[F-18] fluoro-2-deoxy-D-glucose (FDG ) uptake were studied with positron emission tomography in 12 swine in strumented with an external constrictor on the left anterior descendin g coronary artery (LAD). Serial changes in function (by echocardiograp hy), blood flow (with (H2O)-O-15) and FDG were determined weekly. At 1 wk, function was normal and FDG uptake in the LAD and non-LAD regions was 0.43 +/- 0.12 and 0.45 +/- 0.11 mu mol . min(-1). g(-1), respecti vely (not significant). At similar to 5 wk, LAD wall thickening decrea sed to 18 +/- 5 from 27 +/- 8% (P < 0.05), whereas LAD and non-LAD blo od flows were 0.68 +/- 0.28 and 1.03 +/- 0.25 ml . min(-1). g(-1), res pectively (P < 0.05). At that time, FDG uptake in LAD and non-LAD regi ons was 0.60 +/- 0.43 and 0.49 +/- 0.30 mu mol . min(-1). g(-1), respe ctively (P < 0.05). By the use of transmural biopsies (n = 6), ATP and creatine phosphate in the LAD region were 3.62 +/- 0.73 and 5.91 +/- 1.44 mu mol/g wet wt, respectively, and neither differed from values i n remote regions. In this model of chronic ischemia, hypoperfused dysf unctional regions were characterized by enhanced glucose uptake and pr eserved bioenergetics. This supports the concept that the myocardium a dapts to chronic ischemia.