Assessment of Left Ventricular Diastolic Function in a Rat Model of Diabetic Cardiomyopathy with Electrocardiography-gated 18F-FDG PET

117 Objectives Left ventricular (LV) diastolic dysfunction is one of the early signs of cardiac involvement in diabetic patients prior to development of systolic heart failure. We aimed to assess the LV diastolic function by means of electrocardiography (ECG)-gated PET imaging in a rat model of diabetes Methods 18F-FDG PET imaging was performed in a well-established rat model of type 2 diabetes (ZDF fa/fa) (n=6) and ZL control rats (n=6) at age of 13 weeks. Under hyperinsulinemic-euglycemic clamp to enhance cardiac activity, approximately 37MBq of 18F-FDG were administered via tail vein. Subsequently, list-mode PET imaging using a dedicated small animal PET system (Siemens Inveon) with ECG signal recording was performed at 15-35 min after tracer administration. List-mode data were sorted and reconstructed into tomographic images of 16 frames per cardiac cycle. Left ventricular functional parameters of LV ejection fraction (EF) and peak filling rates (PFR) were estimated using clinical automatic ventricular edge detection software (Heart Function View) with minor modifications to adapt for the small rodent heart size. Results At age of 13 weeks, ZDF diabetic rats developed significant hypertrophy of the myocardium at the age of 13 weeks confirmed by post mortem ventricular weight measurements (994±78mg vs. 871±44mg in ZDF diabetic rats vs. ZL controls, p Conclusions Using a combination of ECG-gated 18F-FDG PET imaging and a rat model of diabetes, we successfully identified diastolic dysfunction with preserved systolic ejection at an early stage of diabetic cardiomyopathy.