Myocardial inflammatory images: 18F-FDG PET/CT with heparin loading method in the patients with acute myocardial infarction

Objectives 18F-FDG PET with heparin loading is known to be useful for detecting cardiac inflammatory changes, such as sarcoidosis. We examined whether 18F-FDG with heparin loading was retained in areas of myocardial infarction after successful reperfusion.

Methods 13 patients with acute myocardial infarction who were successfully reperfused by a percutaneous transluminal coronary artery intervention (PCI) performed within 24 hours of onset subsequently underwent 201 Tl SPECT, 18F-FDG PET with heparin loading, and 18F-FDG PET with glucose loading within about 2 weeks of the infarction onset. The standardized uptake values (SUV) of the infarct area and a remote area were measured. A follow-up study was performed in eight patients.

Results 18F-FDG PET with heparin loading revealed an increased uptake in the infarct area, whereas 201 Tl SPECT and 18F-FDG PET with glucose loading showed decreased uptakes. The infarction-to-remote SUV on the 18F-FDG with heparin loading images was correlated with the peak C-reacted protein and white blood cell count. During the chronic phase, the uptake in the infarct area decreased in all the cases.

Conclusions The 18F-FDG uptake with heparin loading images is elevated in infarct areas and may mainly reflect the inflammatory phase of AMI, during which inflammatory cells are abundant. It might be useful for detecting the inflammation phase and therapy effectiveness