Delayed recovery of fatty acid metabolism after transient myocardial ischemia: A potential imaging target for “ischemic memory”
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The myocardium preferentially oxidizes free fatty acids for energy production. However, the dependency of this metabolic pathway on oxygen makes this process vulnerable to ischemia. The energy requirements of the myocardium are subsequently met by the oxidation of carbohydrates, particularly glucose. Recovery of fatty acid metabolism lags behind restoration of perfusion, resulting in the phenomenon ofmetabolic stunning. This decrease of fatty acid utilization following ischemia can be imaged with fatty acid radiotracers, particularly β-Methyl-p-123I-iodophenyl pentadecanoic acid (BMIPP), which demonstrates markedly limited metabolism via β-oxidation, resulting in prolonged retention in the cardiomyocyte. Thus, in patients presenting with chest pain and no prior myocardial infarction, abnormal BMIPP uptake at rest reflects metabolic alteration caused by the preceding ischemia, also termedischemic memory.
KeywordsSingle Photon Emission Compute Tomography Myocardial Perfusion Fatty Acid Metabolism Fatty Acid Uptake Myocardial Perfusion Single Photon Emission Compute Tomography
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References and Recommended Reading
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