Detection of acute myocardial infarction by Tc-99m-labeled D-glucaric acidimaging in patients with acute chest pain

Definitive diagnosis of acute myocardial infarction early in the process is often difficult. An imaging agent that localized quickly and specifically in areas of acute necrosis could provide this critical diagnostic informati on. To determine whether imaging with Tc-99m-labeled D-glucaric acid (GLA) could provide this information, we imaged a group of patients presenting wi th symptoms suggestive of acute infarction. Methods: Twenty-eight patients presenting to the emergency department with symptoms highly suggestive of a cute infarction were injected with Tc-99m-GLA and imaged about 3 h later. R esults: The sensitivity of lesion detection was remarkably time dependent. Fourteen patients with acute infarction injected within 9 h of onset of che st pain had positive scans, even in the presence of persistent occlusion. T he remaining 14 patients had negative scans. Nine patients with negative sc ans had acute infarction but were injected more than 9 h after onset of che st pain. The final diagnosis in the remaining 5 patients was unstable angin a (3 injected <9 h and 2 injected >9 h after onset of chest pain). Six pati ents were reinjected with Tc-99m-GLA 4-6 wk after their initial study to de termine whether persistent positive scans occurred with this agent. All 6 h ad negative scans. Conclusion: This study suggests that Tc-99m-GLA localize s in zones of acute myocardial necrosis when injected within 9 h of onset o f infarction.