Oleg Blagosklonov MD, Presenter: Nothing to Disclose

Orland Angoue, Abstract Co-Author: Nothing to Disclose

Réka Zsigmond, Abstract Co-Author: Nothing to Disclose

Joanna Oettinger MD, Abstract Co-Author: Nothing to Disclose

Nicolas Meneveau MD, Abstract Co-Author: Nothing to Disclose

Hatem Boulahdour MD, PhD, Abstract Co-Author: Nothing to Disclose

Intravenous glucose loading protocol using a 50% dextrose solution in water was recommended by American Society of Nuclear Cardiology (ASNC) for PET myocardial imaging. However, authors report poor image quality in 20-25% of patients, mainly in diabetics, and suggest alternative protocols, for example using a nicotinic acid derivative. The aim of this study was to determine the predictive value of glycaemia, insulin resistance, and free fatty acid (FFA) level to determine the most relevant protocol for patient preparation before myocardial FDG-PET imaging.

The first part of the study was carried out in 68 patients (9 diabetics) after myocardial infarction (MI) underwent FDG-PET scan for detection of myocardial viability. Because fasting blood glucose level was less than 125 mg/dL in all patients, 50% dextrose in water solution (25 g of glucose) was administrated intravenously followed by the injection of 4 to 5 MBq/kg of FDG. The PET images were acquired 1 h later using a PET/CT device (Siemens Biograph Duo, CTI, Knoxville, TN). The PET images were acquired with an axial field of view of 12 cm (15 min/bed). The second part of the study was performed in 111 non selected patients underwent FDG-PET scan for oncology purposes. The PET/CT scan was realized in the same conditions except the dextrose injection and PET acquisition time (3 min/bed). The insulin resistance was calculated using HOMA and QUICKI methods.

Myocardial FDG uptake was adequate in 56 patients (4 diabetics) after MI. The FFA level was 20% higher in 12 patients (5 diabetics) with poor quality of PET images. The correlation between FDG standard uptake value in heart and blood glucose level/insulin resistance was insignificant (R < 0.5) in patients after MI and in non selected patients.

Our results showed that IV glucose loading protocol can be used in diabetic and non diabetic patients undergoing myocardial FDG-PET scan. However, an alternative protocol should be considered in patients with high FFA level. We are continuing our study to determine the threshold of FFA level which suggests the use of such protocol.

FFA level is the most important parameter conditioned myocardial FDG uptake.

Blagosklonov, O, Angoue, O, Zsigmond, R, Oettinger, J, Meneveau, N, Boulahdour, H, Influence of Blood Glucose, Insulin, and Free Fatty Acid Level on Myocardial FDG Uptake.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5005217.html