Feasibility of planar fluorine-18-FDG imaging after recent myocardial infarction to assess myocardial viability

The aim of this study was to define the clinical feasibility of planar myocardial 18 F-fluorodeoxyglucose (FDG) imaging and to assess the relation between 201 Tl, FDG and left ventricular function easy alter myocardial infarction. Methods: Fifty-one patients were studied 5±2 days after infarction. Scintigraphic images were visually and quantatively analyzed using a circumferential profiles technique. FDG use was normalized to the area with maximal 201 Tl uptake. Scintigraphic data were compared with left ventricular wall motion as assessed by ventriculogrnphy in 22 patients. Relative regional 201 Tl uptake was categorized as normal (≥75% of peak activity), moderately reduoed (50%-75%) or severely reduced (<50%). These tracer defects were considered viable if FDG uptake exceeded 201 Tl uptake by ≥20% and/or if FDG uptake was normal (≥75%). All regions with FDG use 20% less than 201 Tl uptake were considered nonviable. Results: Four hundred forty-one myocardial regions were analyzed; 200 showed normal 201 Tl uptake, 241 had reduced uptake, 191 had moderately reduced 201 Tl uptake and 50 regions had severely reduced uptake. Viability for moderately and severely reduced regions was observed in 62% and 48%, respectively. A concordance between flow and metabolism was observed in 38% and 52%, respectively. Conclusion: Myocardial FDG imaging is feasible with standard gamma camera systems and enables the identification of regions with preserved glucose metabolism in patients shortly after infarction